subject:(Reconfigurable Antennas)

University of Oklahoma

1. Winniford, Paul. Reconfigurable and multiband antennas with resonant and reactive loads.

Degree: PhD, 2020, University of Oklahoma

► Reactive and resonant loads have been used from the very beginning of antenna design to improve impedance matching, bandwidth, and current distributions on antennas, and… (more)

Subjects/Keywords: Antennas; Reconfigurable Antennas; Multifrequency Antennas; Loaded Antennas

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APA (6^th Edition):

Winniford, P. (2020). Reconfigurable and multiband antennas with resonant and reactive loads. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/326683

Chicago Manual of Style (16^th Edition):

Winniford, Paul. “Reconfigurable and multiband antennas with resonant and reactive loads.” 2020. Doctoral Dissertation, University of Oklahoma. Accessed March 05, 2021. http://hdl.handle.net/11244/326683.

MLA Handbook (7^th Edition):

Winniford, Paul. “Reconfigurable and multiband antennas with resonant and reactive loads.” 2020. Web. 05 Mar 2021.

Vancouver:

Winniford P. Reconfigurable and multiband antennas with resonant and reactive loads. [Internet] [Doctoral dissertation]. University of Oklahoma; 2020. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/11244/326683.

Council of Science Editors:

Winniford P. Reconfigurable and multiband antennas with resonant and reactive loads. [Doctoral Dissertation]. University of Oklahoma; 2020. Available from: http://hdl.handle.net/11244/326683

Macquarie University

2. Qin, Pei-Yuan. Study of reconfigurable antennas and their applications in MIMO systems.

Degree: 2012, Macquarie University

URL: http://hdl.handle.net/1959.14/1205416

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Empirical thesis.

"Dissertation submitted in fulfilment of the requirements for the degree of Doctor of Philosophy."

Bibliography: pages [165]-183.

1. Introduction – 2. Background –… (more)

▼

Empirical thesis.

"Dissertation submitted in fulfilment of the requirements for the degree of Doctor of Philosophy."

Bibliography: pages [165]-183.

1. Introduction – 2. Background – 3. Frequency reconfigurable antennas – 4. A polarization reconfigurable antenna – 5. A pattern reconfigurable antenna – 6. A reconfigurable antenna with frequency and polarization agility – 7. Applications of reconfigurable antennas in MIMO systems – 8. Conclusions and future work.

Reconfigurable antennas (RAs) are at the frontier of current antenna research and are excellent antenna candidates for advanced wireless communication applications. The basic structure of a RA is similar to that of a conventional one; however, by using electrical, mechanical or other means to change the fundamental operating mechanism of an individual radiator, the frequency and radiation characteristics of the RA can be varied significantly. This makes a single RA equal to multiple antennas with fixed functionalities. Thanks to the agility and diversity of RAs, they find wide application in Software Defined Radios, multiple-input-multiple-output (MIMO) systems, diversity communication systems, satellite communications, and military communication systems.

One of the greatest design challenges for antenna reconfigurability is changing one characteristic of an antenna, such as the frequency response, without affecting others (polarization or radiation pattern), since the frequency response and the radiation characteristics of an antenna are always highly related. Furthermore, for RAs using electronic components to achieve reconfigurability, the design of an effective dc bias network that has a limited influence on the antenna performance is another important design issue for antenna engineers.

In this dissertation, motivated by the increasing significance of RAs as well as the demand for new design methods for compact RAs with simple dc bias networks, a thorough investigation is presented on RAs in terms of frequency, polarization, pattern, as well as compound frequency and polarization RAs. A few novel RAs with dc bias networks are designed, fabricated and measured. And they have demonstrated many advantages over other corresponding reported designs.

In addition, a literature review reveals that, although a considerable number of papers on RAs have been published, much fewer are reported on the study of the applications of RAs in wireless communication systems. In order to examine the practical application of RAs, the proposed polarization and pattern RAs are incorporated separately in 2 x 2 MIMO orthogonal frequency division multiplexing (OFDM) systems. Real-time channel measurements are conducted in both line-of-sight (LOS) and non-LOS (NLOS) scenarios. Compared to the systems with non-reconfigurable antennas, a significant enhancement of the system capacity is accomplished.

1 online resource (xxvi, 183 pages) illustrations

Advisors/Committee Members: Macquarie University. Department of Electronic Engineering.

Subjects/Keywords: Antennas (Electronics) – Design and construction; Reconfigurable antennas

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Qin, P. (2012). Study of reconfigurable antennas and their applications in MIMO systems. (Doctoral Dissertation). Macquarie University. Retrieved from http://hdl.handle.net/1959.14/1205416

Chicago Manual of Style (16^th Edition):

Qin, Pei-Yuan. “Study of reconfigurable antennas and their applications in MIMO systems.” 2012. Doctoral Dissertation, Macquarie University. Accessed March 05, 2021. http://hdl.handle.net/1959.14/1205416.

MLA Handbook (7^th Edition):

Qin, Pei-Yuan. “Study of reconfigurable antennas and their applications in MIMO systems.” 2012. Web. 05 Mar 2021.

Vancouver:

Qin P. Study of reconfigurable antennas and their applications in MIMO systems. [Internet] [Doctoral dissertation]. Macquarie University; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1959.14/1205416.

Council of Science Editors:

Qin P. Study of reconfigurable antennas and their applications in MIMO systems. [Doctoral Dissertation]. Macquarie University; 2012. Available from: http://hdl.handle.net/1959.14/1205416

University of New South Wales

3. Gong, Liang. Radiation pattern reconfigurable single-arm spiral antenna.

Degree: Electrical Engineering & Telecommunications, 2013, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/52961 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11639/SOURCE01?view=true

► Pattern reconfigurable antennas have aroused intensive research recently because of their critical role in wireless communication and military applications. Phased arrays offer best beam steering… (more)

▼ Pattern reconfigurable antennas have aroused intensive research recently because of their critical role in wireless communication and military applications. Phased arrays offer best beam steering ability but they are balky and costly built. Alternatively, cost effective solutions can be achieved by introducing switch circuitry into simpler antenna structures like ring antennas, slot antennas, and spiral antennas. This thesis focuses on single arm rectangular spiral antennas capable to steer the beam by switches attached on the spiral. Two novel beam steering spiral antennas operating at 3.3 GHz with wide beam coverage have been proposed. Simulation was conducted using Ansys HFSS. RF-MEMS varactors or PIN diodes are used as switches. Simulation results show wider azimuth plane coverage than existed designs because of the added bridges and extra switches. The location of the bridges and PIN diodes are determined by parametric sweep simulation process which has been detailed.In order to validate the simulation results, two antennas are fabricated using Rogers 4350 substrate and PIN diodes. They are center fed by SMA connectors with inner pin connecting the starting point of the spiral. Up to three DC biasing signals of both positive and negative voltages are required to achieve various cases for the switches. Since DC supplies are directly connected with spiral arm, biasing line, pad, and quarter wavelength stubs are needed to open circuit RF signals. Although the geometry and locations of them have been optimized, analysis indicates that these elements for biasing purposes generate errors and disagreements from simulation results. The wire connecting DC supply and range errors lead to discrepancy between simulation and measurement.Simulation and measured results for reflection coefficient, radiation pattern (both RHCP and LHCP), gain, and axial ratio are compared. Measurement methods by spinning source, two-orthogonal-cut, and cavity backed circular spiral antennas are detailed. In addition, a thorough review of the literature relating to recent high speed communication technology and reconfigurable antennas have been performed. RF-MEMS fabrication processes are described. A future project relating to a RF-MEMS version for high performance pattern reconfigurability is planned in the conclusion. Advisors/Committee Members: Rodica, Ramer, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW.

Subjects/Keywords: Beam steering; Spiral antennas; Reconfigurable antennas

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APA (6^th Edition):

Gong, L. (2013). Radiation pattern reconfigurable single-arm spiral antenna. (Masters Thesis). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/52961 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11639/SOURCE01?view=true

Chicago Manual of Style (16^th Edition):

Gong, Liang. “Radiation pattern reconfigurable single-arm spiral antenna.” 2013. Masters Thesis, University of New South Wales. Accessed March 05, 2021. http://handle.unsw.edu.au/1959.4/52961 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11639/SOURCE01?view=true.

MLA Handbook (7^th Edition):

Gong, Liang. “Radiation pattern reconfigurable single-arm spiral antenna.” 2013. Web. 05 Mar 2021.

Vancouver:

Gong L. Radiation pattern reconfigurable single-arm spiral antenna. [Internet] [Masters thesis]. University of New South Wales; 2013. [cited 2021 Mar 05]. Available from: http://handle.unsw.edu.au/1959.4/52961 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11639/SOURCE01?view=true.

Council of Science Editors:

Gong L. Radiation pattern reconfigurable single-arm spiral antenna. [Masters Thesis]. University of New South Wales; 2013. Available from: http://handle.unsw.edu.au/1959.4/52961 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11639/SOURCE01?view=true

Brunel University

4. Abutarboush, Hattan F. Fixed and reconfigurable multiband antennas.

Degree: PhD, 2011, Brunel University

URL: http://bura.brunel.ac.uk/handle/2438/9037 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542871

► With the current scenario of development of antennas in the wireless communication field, the need of compact multiband, multifunctional and cost effective antenna is on… (more)

▼ With the current scenario of development of antennas in the wireless communication field, the need of compact multiband, multifunctional and cost effective antenna is on the rise. The objective of this thesis is to present fixed and reconfigurable techniques and methods for small and slim multiband antennas, which are applicable to serve modern small and slime wireless, mobile and cognitive radio applications. In the fixed designs, independent control of the operating frequencies is investigated to enhance the antennas capabilities and to give the designer an additional level of freedom to design the antenna for other bands easily without altering the shape or the size of the antenna. In addition, for mobile phone antenna, the effect of user’s hand and mobile phone housing are studied to be with minimum effect. Although fixed multiband antennas can widely be used in many different systems or devices, they lack flexibility to accommodate new services compared with reconfigurable antennas. A reconfigurable antenna can be considered as one of the key advances for future wireless communication transceivers. The advantage of using a reconfigurable antenna is to operate in multiband where the total antenna volume can be reused and therefore the overall size can be reduced. Moreover, the future of cell phones and other personal mobile devices require compact multiband antennas and smart antennas with reconfigurable features. Two different types of frequency reconfigurability are investigated in this thesis: switchable and tunable. In the switchable reconfigurability, PIN diodes have been used so the antenna’s operating frequencies can hop between different services whereas varactor diode with variable capacitance allow the antenna’s operating frequencies to be fine-tuned over the operating bands. With this in mind, firstly, a switchable compact and slim antenna with two patch elements is presented for cognitive radio applications where the antenna is capable of operating in wideband and narrow bands depending on the states of the switches. In addition to this, a switchable design is proposed to switch between single, dual and tri bands applications (using a single varactor diode to act as a switch at lower capacitance values) with some fine tuning capabilities for the first and third bands when the capacitance of the diode is further increased. Secondly, the earlier designed fixed antennas are modified to be reconfigurable with fine-tuning so that they can be used for more applications in both wireless and mobile applications with the ability to control the bands simultaneously or independently over a wide range. Both analytical and numerical methods are used to implement a realistic and functional design. Parametric analyses using simulation tools are performed to study critical parameters that may affect the designs. Finally, the simulated designs are fabricated, and measured results are presented that validate the design approaches.

Subjects/Keywords: 621.3; Small antennas; Fixed antennas; Reconfigurable antennas; Mobile antennas; Cognitive radio

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APA (6^th Edition):

Abutarboush, H. F. (2011). Fixed and reconfigurable multiband antennas. (Doctoral Dissertation). Brunel University. Retrieved from http://bura.brunel.ac.uk/handle/2438/9037 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542871

Chicago Manual of Style (16^th Edition):

Abutarboush, Hattan F. “Fixed and reconfigurable multiband antennas.” 2011. Doctoral Dissertation, Brunel University. Accessed March 05, 2021. http://bura.brunel.ac.uk/handle/2438/9037 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542871.

MLA Handbook (7^th Edition):

Abutarboush, Hattan F. “Fixed and reconfigurable multiband antennas.” 2011. Web. 05 Mar 2021.

Vancouver:

Abutarboush HF. Fixed and reconfigurable multiband antennas. [Internet] [Doctoral dissertation]. Brunel University; 2011. [cited 2021 Mar 05]. Available from: http://bura.brunel.ac.uk/handle/2438/9037 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542871.

Council of Science Editors:

Abutarboush HF. Fixed and reconfigurable multiband antennas. [Doctoral Dissertation]. Brunel University; 2011. Available from: http://bura.brunel.ac.uk/handle/2438/9037 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542871

University of Adelaide

5. Zainarry, Siti Nailah Mastura. Recon gurable Antennas Based on Varactor-Loaded Stubs.

Degree: 2019, University of Adelaide

URL: http://hdl.handle.net/2440/124595

► The term “reconfigurable” is typically used for devices which exhibit some flexibility of functionalities and agility in their operation characteristics, with the aim of achieving… (more)

▼ The term “reconfigurable” is typically used for devices which exhibit some flexibility of functionalities and agility in their operation characteristics, with the aim of achieving high performance in various conditions. In antenna technology, the reconfiguration can be fulfilled through several techniques that provide an ability to modify the electrical current on the antenna’s structure, primarily to accomplish a physically realised new response. The main key to the reconfigurable antenna application is their potential to avoid the use of multiple antennas for multi-functionality, thus facilitating miniaturisation of the antenna system configuration. In this context, several novel reconfigurable antennas with a wide performance range are proposed in this thesis. Varactor-loaded stubs are used as tuning mechanism for these microwave antenna designs with improved performance throughout this thesis. Two types of electromagnetic structures are studied in this work, namely reconfigurable antennas and reconfigurable periodic structures, with these two main topics building the two main major parts of this thesis. In its first main part, the thesis proposes reconfigurable antenna designs with combined frequency and pattern reconfigurable characteristics. The main focus is first on the manipulation of near-resonant current distributions in a two-element array antenna as well as the optimisation of their feeding through T-junction power dividers. Each element has a controllable active component that allows the antenna to be tuned to different operating frequencies, while the concurrent adaption of the two elements is the basis of continuous beam scanning characteristics. Next, the thesis examines the exploitation of a single-element antenna structure based on the same operation principle. An optimisation procedure including a study of relevant design parameters is also presented. The core contribution for the two-element array and the single-element antenna is that they combine frequency-reconfigurability with effective beam scanning. The main difference between the two designs however is that they scan in the H-plane and the E-plane, respectively. In the second main part, the thesis focuses on a reconfigurable reflectarray antenna design. Potential applications of this advanced antenna design include the development of high gain antennas with various controllable reflection beam directions throughout a wide range of operation frequencies. The proposed reflectarray antenna unit cell is firstly proposed, together with an opimisation of the antenna characteristics in terms of reflection loss and phase range performance. It is further shown that the proposed antenna provides an excellent performance compared to the state-of-the-art. Performance measures include a near full phase tuning range of about 300 to 320 with a reflection loss of magnitude better than 3 dB within a fractional frequency range of operation of 18%. In contrast, most reflectarray antenna designs in the literature provide a limited phase range at a fixed… Advisors/Committee Members: Fumeaux, Christophe (advisor), Lim, Cheng Chew (advisor), School of Electrical and Electronic Engineering (school).

Subjects/Keywords: Reconfigurable antennas; Frequency-reconfigurable; Pattern-reconfigurable; Varactor-loaded stubs

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APA (6^th Edition):

Zainarry, S. N. M. (2019). Recon gurable Antennas Based on Varactor-Loaded Stubs. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/124595

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zainarry, Siti Nailah Mastura. “Recon gurable Antennas Based on Varactor-Loaded Stubs.” 2019. Thesis, University of Adelaide. Accessed March 05, 2021. http://hdl.handle.net/2440/124595.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zainarry, Siti Nailah Mastura. “Recon gurable Antennas Based on Varactor-Loaded Stubs.” 2019. Web. 05 Mar 2021.

Vancouver:

Zainarry SNM. Recon gurable Antennas Based on Varactor-Loaded Stubs. [Internet] [Thesis]. University of Adelaide; 2019. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/2440/124595.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zainarry SNM. Recon gurable Antennas Based on Varactor-Loaded Stubs. [Thesis]. University of Adelaide; 2019. Available from: http://hdl.handle.net/2440/124595

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

NSYSU

6. Wu , Pei-rong. Low-Profile Open-Slot LTE Smartphone Antenna and Its MIMO Performance Study.

Degree: Master, Electrical Engineering, 2015, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0523115-161205

► Two different kinds of low-profile open-slot antenna to achieve a low profile of 7 and 5 mm, respectively, to cover the LTE operation (698~960/1710~2690 MHz)… (more)

Subjects/Keywords: LTE antennas; slot antennas; open slot antennas; Low-profile antennas; mobile antennas; passively reconfigurable antennas; MIMO antennas

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APA (6^th Edition):

Wu , P. (2015). Low-Profile Open-Slot LTE Smartphone Antenna and Its MIMO Performance Study. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0523115-161205

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wu , Pei-rong. “Low-Profile Open-Slot LTE Smartphone Antenna and Its MIMO Performance Study.” 2015. Thesis, NSYSU. Accessed March 05, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0523115-161205.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wu , Pei-rong. “Low-Profile Open-Slot LTE Smartphone Antenna and Its MIMO Performance Study.” 2015. Web. 05 Mar 2021.

Vancouver:

Wu P. Low-Profile Open-Slot LTE Smartphone Antenna and Its MIMO Performance Study. [Internet] [Thesis]. NSYSU; 2015. [cited 2021 Mar 05]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0523115-161205.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wu P. Low-Profile Open-Slot LTE Smartphone Antenna and Its MIMO Performance Study. [Thesis]. NSYSU; 2015. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0523115-161205

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

7. Raptis, Vasileios. Μελέτη και ανάπτυξη προσαρμοσμένου συστήματος λήψης φέροντος.

Degree: 2012, University of Ioannina; Πανεπιστήμιο Ιωαννίνων

URL: http://hdl.handle.net/10442/hedi/46263

►

Recent technological developments provide the fact that wireless communication devices could besmaller in size. Specifically, the size of the antenna is obviously an important factor… (more)

▼

Recent technological developments provide the fact that wireless communication devices could besmaller in size. Specifically, the size of the antenna is obviously an important factor which limits theoverall size of the devices. Over the past few years, new low profile antenna designs have beendeveloped for portable wireless devices. The basic feature of low-profile antennas is their limitedbandwidth. The problems that need to be solved when using these devices with regard to the antenna system are reported below: The proximity of the user towards the device or other external environmental factors (such as metal objects, walls, trees) alter the antenna frequency resonance. This fact deteriorates the received signal quality from the antenna during reception and additional transmitted power is needed in order to maintain the communication link during broadcast. The use of wide bandwidth antennas during broadcasting, as opposed to narrowband antennas, creates interference problems from neighboring stations. Consequently, the use of filters at the input ofthe receiving signal is necessary to eliminate noise from neighboring frequencies. This translates into a further reduction in the power of the received signal from these antennas and in the demand of additional material costs. These problems are confronted in this thesis. An antenna is suggested with narrow bandwidth and with continuous re-tuning of its operating frequency. The methodology that is followed by priority order is modeling, simulation, constructing and measurement of the PIFA antennas and finally the construction of a system which has the capability of changing the resonant frequency using a variable capacitor. The results - conclusions of this dissertation are oriented towards using a variable capacity of a varactor embedded into a PIFA antenna, which this fact gives the capability of changing the resonant frequency for avoiding the unwanted phenomenon at GSM frequencies.

Οι πρόσφατες τεχνολογικές εξελίξεις επιτρέπουν στις ασύρματες συσκευές επικοινωνίας να γίνουνμικρότερες σε μέγεθος. Το μέγεθος της κεραίας είναι προφανώς ένας σημαντικός παράγοντας πουπεριορίζει το τελικό μέγεθος των συσκευών. Στη διάρκεια των τελευταίων ετών, έχουν αναπτυχθεί νέα σχέδια κεραιών χαμηλού προφίλ για φορητές ασύρματες συσκευές. Το βασικό χαρακτηριστικό των κεραιών χαμηλού προφίλ είναι το περιορισμένο εύρος ζώνης τους. Τα προβλήματα που πρέπει να λυθούν κατά τη χρήση αυτών των συσκευών σε ότι αφορά το σύστημα των κεραιών είναι:Η χρήση μεγάλου εύρους ζώνης κεραιών στις συσκευές καθιστά αναγκαία τη χρήση φίλτρων στηνείσοδο του σήματος στους δέκτες για την απάλειψη του θορύβου από γειτονικές συχνότητες. Αυτόμεταφράζεται σε επιπλέον μείωση της ισχύος του λαμβανόμενου σήματος από αυτές τις κεραίες καιεπιπλέον κόστος υλικών. Αυτά τα προβλήματα καλείται να ανταπεξέλθει η παρούσα διατριβή. Προτείνει τη χρήση στενού εύρους ζώνης κεραίας PIFA με συνεχή επανασυντονισμό της συχνότητας λειτουργίας της. Με την ανά τακτά χρονικά διαστήματα δειγματοληψία της συμπεριφοράς της ελέγχεται και…

Subjects/Keywords: Κεραίες; Επαναπροσδιοριζόμενη; Antennas; GSM; Reconfigurable; Varactor; PIFA

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APA (6^th Edition):

Raptis, V. (2012). Μελέτη και ανάπτυξη προσαρμοσμένου συστήματος λήψης φέροντος. (Thesis). University of Ioannina; Πανεπιστήμιο Ιωαννίνων. Retrieved from http://hdl.handle.net/10442/hedi/46263

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Raptis, Vasileios. “Μελέτη και ανάπτυξη προσαρμοσμένου συστήματος λήψης φέροντος.” 2012. Thesis, University of Ioannina; Πανεπιστήμιο Ιωαννίνων. Accessed March 05, 2021. http://hdl.handle.net/10442/hedi/46263.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Raptis, Vasileios. “Μελέτη και ανάπτυξη προσαρμοσμένου συστήματος λήψης φέροντος.” 2012. Web. 05 Mar 2021.

Vancouver:

Raptis V. Μελέτη και ανάπτυξη προσαρμοσμένου συστήματος λήψης φέροντος. [Internet] [Thesis]. University of Ioannina; Πανεπιστήμιο Ιωαννίνων; 2012. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10442/hedi/46263.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Raptis V. Μελέτη και ανάπτυξη προσαρμοσμένου συστήματος λήψης φέροντος. [Thesis]. University of Ioannina; Πανεπιστήμιο Ιωαννίνων; 2012. Available from: http://hdl.handle.net/10442/hedi/46263

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Penn State University

8. Turpin, Jeremiah Paul. A Switchable Magnetic Low-index Metamaterial for use in a Dynamically Reconfigurable Beam-scanning Lens Antenna with a Single Feed.

Degree: 2014, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/23268

► Metamaterials and Transformation Optics (TO) have been used to design and implement many novel electromagnetic devices that can achieve effects not possible using conventional materials.… (more)

▼ Metamaterials and Transformation Optics (TO) have been used to design and implement many novel electromagnetic devices that can achieve effects not possible using conventional materials. Compact high-gain antennas are one of the more popular and successful emerging applications for the new TO and metamaterial design approaches. This dissertation details an extension of uniaxial near-zero index metamaterial lenses through the incorporation of a tunable or reconfigurable metamaterial as a replacement for the static metamaterial of the original antenna. A design is presented for a beam-scanning TO lens that allows an arbitrary number of beams at controlled magnitudes to be dynamically synthesized from a single omnidirectional source, unlike the equivalent antenna constructed using an array. A cylindrical slab of zero-index magnetic metamaterial controls the radiation pattern by altering the effective shape of the lens through switching of selected regions 'off' to emulate free-space conditions. A design for a switchable metamaterial is presented that allows for digital control over its bulk properties, from near-zero-index to near-free-space at the targeted operational frequency. Extensive modeling and simulations were performed for the design of the lens and metamaterial and during the analysis of measurement results. Initial prototypes of the tunable metamaterial were fabricated and characterized to confirm the original measurements, and the design updated to incorporate the measured data. These measurements were performed using custom test fixtures manufactured specifically for this project. Finally, a simplified prototype lens was manufactured and characterized in an anechoic as a proof-of-concept for the design. This dissertation presents the lens and metamaterial specifications, as well as the design process and considerations that were determined for practical tunable and reconfigurable metamaterials. Although the focus is on the particular example of the beam-scanning reconfigurable antenna, the analysis and modeling methods presented here are applicable to any reconfigurable metamaterial application. Advisors/Committee Members: Douglas Henry Werner, Dissertation Advisor/Co-Advisor, Douglas Henry Werner, Committee Chair/Co-Chair, Pingjuan Li Werner, Committee Member, Victor P Pasko, Committee Member, Douglas Edward Wolfe, Committee Member.

Subjects/Keywords: electromagnetics; antennas; reconfigurable pattern antennas; metamaterial; Transformation Optics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Turpin, J. P. (2014). A Switchable Magnetic Low-index Metamaterial for use in a Dynamically Reconfigurable Beam-scanning Lens Antenna with a Single Feed. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/23268

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Turpin, Jeremiah Paul. “A Switchable Magnetic Low-index Metamaterial for use in a Dynamically Reconfigurable Beam-scanning Lens Antenna with a Single Feed.” 2014. Thesis, Penn State University. Accessed March 05, 2021. https://submit-etda.libraries.psu.edu/catalog/23268.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Turpin, Jeremiah Paul. “A Switchable Magnetic Low-index Metamaterial for use in a Dynamically Reconfigurable Beam-scanning Lens Antenna with a Single Feed.” 2014. Web. 05 Mar 2021.

Vancouver:

Turpin JP. A Switchable Magnetic Low-index Metamaterial for use in a Dynamically Reconfigurable Beam-scanning Lens Antenna with a Single Feed. [Internet] [Thesis]. Penn State University; 2014. [cited 2021 Mar 05]. Available from: https://submit-etda.libraries.psu.edu/catalog/23268.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Turpin JP. A Switchable Magnetic Low-index Metamaterial for use in a Dynamically Reconfigurable Beam-scanning Lens Antenna with a Single Feed. [Thesis]. Penn State University; 2014. Available from: https://submit-etda.libraries.psu.edu/catalog/23268

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

9. Malakooti, Seyedali. Ultrawideband and Multi-state Reconfigurable Antennas with Sum and Difference Radiation Patterns.

Degree: 2019, University of Adelaide

URL: http://hdl.handle.net/2440/124259

► Pattern diversity is a term used to describe the operation of several antenna elements working together to produce multiple different radiation patterns with the aim… (more)

▼ Pattern diversity is a term used to describe the operation of several antenna elements working together to produce multiple different radiation patterns with the aim of improving the quality and reliability of a communications system. One useful implementation of pattern diversity considers sum and difference radiation patterns which can be exploited to extend high-gain space coverage and tackle multipath fading. The conventional forms of such pattern diversity antennas are generally working at a single or multiple narrowband frequencies and are designed for specific applications. Hence, generating sum and difference pattern diversity in wide range of frequencies requires the development of new pattern diversity antenna designs. Ultrawideband and frequency reconfigurable designs of pattern diversity antennas are desirable to help reduce the cost and increase the flexibility in applications of pattern diversity antennas. These two types of performances constitute the principal parts of this thesis. The first part of this thesis deals with the challenges of designing ultrawideband Vivaldi antennas with sum and difference radiation patterns. When two Vivaldi antennas are placed next to each other, two mutually exclusive phenomena of grating lobe generation at the highest end of frequency and mutual coupling at the lowest end of frequency will define the bandwidth. Hence, to enhance the bandwidth, the separation between the antenna elements is reduced, which delays the grating lobes generation, and the coupling at lower frequencies is mitigated by introducing an asymmetry in the design of each Vivaldi antenna element. It is shown that this method can be extended to multi-element Vivaldi antennas for higher gain. Next, the bandwidth is further enhanced by adding two vertical metal slabs between the antenna elements improving the isolation at lower frequencies. The proposed antennas use commercially available couplers as feeding networks. As a potential replacement for couplers, an out-of-phase power divider with unequal power division is also proposed. In the second part of this thesis, the pattern diversity function is combined with multistate frequency-reconfigurable filtering functions in a series of novel designs. In the first proposed design, two quasi-Yagi-Uda antennas are used for pattern diversity, while two switchable and reconfigurable bandpass-to-bandstop filters are used to excite the antenna elements. The whole system is excited by an external commercially available rat-race coupler. In a next step, this design is modified to attain wideband, tunable bandpass, and tunable bandstop operations while obviating the need for an external coupler by using three antenna elements excited by a switchable power divider. In another implementation, the filtering functions is extended to dual-band independently tunable bandpass and bandstop to excite wideband antennas. While all the former designs featured E-plane pattern diversity, in another design aiming at increasing space coverage, a switchable patch antennas with sum… Advisors/Committee Members: Fumeaux, Christophe (advisor), Ranasinghe, Damith Chintana (advisor), School of Electrical and Electronic Engineering (school).

Subjects/Keywords: Ultrawideband antennas; Reconfigurable antennas; pattern diversity; filtering response

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Malakooti, S. (2019). Ultrawideband and Multi-state Reconfigurable Antennas with Sum and Difference Radiation Patterns. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/124259

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Malakooti, Seyedali. “Ultrawideband and Multi-state Reconfigurable Antennas with Sum and Difference Radiation Patterns.” 2019. Thesis, University of Adelaide. Accessed March 05, 2021. http://hdl.handle.net/2440/124259.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Malakooti, Seyedali. “Ultrawideband and Multi-state Reconfigurable Antennas with Sum and Difference Radiation Patterns.” 2019. Web. 05 Mar 2021.

Vancouver:

Malakooti S. Ultrawideband and Multi-state Reconfigurable Antennas with Sum and Difference Radiation Patterns. [Internet] [Thesis]. University of Adelaide; 2019. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/2440/124259.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Malakooti S. Ultrawideband and Multi-state Reconfigurable Antennas with Sum and Difference Radiation Patterns. [Thesis]. University of Adelaide; 2019. Available from: http://hdl.handle.net/2440/124259

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech

10. Cummings, Nathan Patrick. Active Antenna Bandwidth Control Using Reconfigurable Antenna Elements.

Degree: PhD, Electrical and Computer Engineering, 2003, Virginia Tech

URL: http://hdl.handle.net/10919/29990

► Reconfigurable antennas represent a recent innovation in antenna design that changes from classical fixed-form, fixed-function antennas to modifiable structures that can be adapted to fit… (more)

Subjects/Keywords: bandwidth control; reconfigurable antennas; antennas

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APA (6^th Edition):

Cummings, N. P. (2003). Active Antenna Bandwidth Control Using Reconfigurable Antenna Elements. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/29990

Chicago Manual of Style (16^th Edition):

Cummings, Nathan Patrick. “Active Antenna Bandwidth Control Using Reconfigurable Antenna Elements.” 2003. Doctoral Dissertation, Virginia Tech. Accessed March 05, 2021. http://hdl.handle.net/10919/29990.

MLA Handbook (7^th Edition):

Cummings, Nathan Patrick. “Active Antenna Bandwidth Control Using Reconfigurable Antenna Elements.” 2003. Web. 05 Mar 2021.

Vancouver:

Cummings NP. Active Antenna Bandwidth Control Using Reconfigurable Antenna Elements. [Internet] [Doctoral dissertation]. Virginia Tech; 2003. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/10919/29990.

Council of Science Editors:

Cummings NP. Active Antenna Bandwidth Control Using Reconfigurable Antenna Elements. [Doctoral Dissertation]. Virginia Tech; 2003. Available from: http://hdl.handle.net/10919/29990

University of Adelaide

11. Chen, Shengjian Jammy. Flexible, wearable and reconfigurable antennas based on novel conductive materials: graphene, polymers and textiles.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/112809

► Due to high demand and ubiquity of novel wireless communication systems, numerous new technical challenges have risen in modern antenna design to satisfy emerging unconventional… (more)

▼ Due to high demand and ubiquity of novel wireless communication systems, numerous new technical challenges have risen in modern antenna design to satisfy emerging unconventional system requirements. Typical examples include radio frequency identification (RFID) systems and wearable electronic systems. RFID systems usually consist of a reader and a tag integrated with an antenna which is attached to the item(s) to be tracked. Therefore, for the commercial viability of the system, it is desired to have flexible, light-weight, highly integratable and low-cost antennas for the tags. These characteristics are also desired for the antennas used in wearable electronic systems, with an additional critical requirement, namely electrical and mechanical robustness to the loading effect from the human body when worn. Hence traditional metallic conductors and dielectric materials such as ceramics are usually not suitable, as these materials lack mechanical flexibility and resilience while having a high intrinsic cost. In this context, flexible, wearable and reconfigurable antennas based on novel conductive and dielectric materials are of significant interest. This is in line with the goals of this thesis which comprise four main different objectives. Firstly, the dissertation presents the development of non-metallic, highly efficient and flexible antennas based on conductive polymers and graphene thin films as conductors. Through efficiency-driven and material-oriented engineering methods, it is shown that these antennas can overcome the process-related inherent limitations of the non-metallic conductors, demonstrating the excellent potential of these novel materials. Secondly, the thesis also focuses on the investigation of appropriate shorting strategies and connection solutions for textile antennas, in terms of ease of fabrication, connection reliability and antenna efficiency. This work aims to provide reliable and efficient solutions to the critical connection requirement between flexible textile antennas and rigid electronic components. Thirdly, modular and reconfigurable wearable textile antennas which provide passive and/or active system reconfigurability are proposed, based on commercial snap-on buttons operating as shorting vias and connectors. The modular wearable antenna concept utilizes different modules which are designed to achieve specific antenna characteristics and fulfill various functionalities. The reconfigurable antenna is based on a reconfigurable module which integrates varactors and a dedicated bias circuit board inside snap-on buttons. This button module can solve the main challenge in realizing reliable connections between bias circuit, lump components and textiles, which arises because of the very different physical properties of rigid and flexible components. Fourthly, the last part of the thesis presents a compact and high efficiency series-fed microstrip patch array and a flexible dielectric resonator antenna, as examples of novel designs suitable for wearable applications. All the results and… Advisors/Committee Members: Fumeaux, Christophe (advisor), Ranasinghe, Damith Chinthana (advisor), Kaufmann, Thomas (advisor), School of Electrical and Electronic Engineering (school).

Subjects/Keywords: wearable antennas; textile antennas; reconfigurable antennas; flexible antennas; UWB antennas; graphene; conductive polymer; E-textile; RFID

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APA (6^th Edition):

Chen, S. J. (2017). Flexible, wearable and reconfigurable antennas based on novel conductive materials: graphene, polymers and textiles. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/112809

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Chen, Shengjian Jammy. “Flexible, wearable and reconfigurable antennas based on novel conductive materials: graphene, polymers and textiles.” 2017. Thesis, University of Adelaide. Accessed March 05, 2021. http://hdl.handle.net/2440/112809.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Chen, Shengjian Jammy. “Flexible, wearable and reconfigurable antennas based on novel conductive materials: graphene, polymers and textiles.” 2017. Web. 05 Mar 2021.

Vancouver:

Chen SJ. Flexible, wearable and reconfigurable antennas based on novel conductive materials: graphene, polymers and textiles. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/2440/112809.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chen SJ. Flexible, wearable and reconfigurable antennas based on novel conductive materials: graphene, polymers and textiles. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/112809

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – San Diego

12. Avser, Bilgehan. Frequency Tunable Antennas and Novel Phased Array Feeding Networks for Next Generation Communication Systems.

Degree: Electrical Engineering (Electronic Circuits and Systems), 2015, University of California – San Diego

URL: http://www.escholarship.org/uc/item/6cq329s4

► The thesis presents three dual-band frequency tunable antennas for carrier aggregation systems and two new feeding networks for reducing the number of phase shifters in… (more)

▼ The thesis presents three dual-band frequency tunable antennas for carrier aggregation systems and two new feeding networks for reducing the number of phase shifters in limited-scan arrays. First, single- and dual-feed, dual-frequency, low-profile antennas with independent frequency tuning using varactor diodes are presented. The dual-feed planar inverted F-antenna (PIFA) has two operating frequencies which are independently tuned at 0.7 – 1.1 GHz and at 1.7 – 2.3 GHz with better than −10 dB impedance match. The isolation between the high-band and the low-band ports is > 13 dB; hence, one resonant frequency can be tuned without affecting the other. The single-feed contiguous-dual-band antenna has two resonant frequencies, which are independently tuned at 1.2 – 1.6 GHz at 1.6 – 2.3 GHz with better than −10 dB impedance match for most of the tuning range. And the single-feed dual-band antenna has two resonant frequencies, which are independently tuned at 0.7 – 1.0 GHz at 1.7 – 2.3 GHz with better than −10 dB impedance match for most of the tuning range. The tuning is done using varactor diodes with a capacitance range from 0.8 to 3.8 pF, which is compatible with RF MEMS devices. The antenna volumes are 63 × 100 × 3.15 mm³ on ε_r = 3.55 substrates and the measured antenna efficiencies vary between 25% and 50% over the tuning range. The application areas are in carrier aggregation systems for fourth generation (4G) wireless systems. Next, a new phased array feeding network that employs random sequences of non-uniform sub-arrays (and a single phase shifter for each sub-array) is presented. When these sequences are optimized, the resulting phased arrays can scan over a wide region with low sidelobe levels. Equations for analyzing the random arrays and an algorithm for optimizing the array sequences are presented. Multiple random-solutions with different number of phase shifters and different set of sub-array groups are analyzed and design guidelines are presented. The performance of the random array feeding scheme is compared to the conventional uniform sub-arraying for multiple cases. It is shown that with the random feeding networks, the number of phase shifters can be reduced up to 30% while preserving the system performance. This results in more affordable and more reliable systems. The proposed feeding network is demonstrated for a 30 element array of slot- fed patch antennas at 7.9 GHz. The fabricated array uses 12 phase shifters, has a half power beamwidth (HPBW) of 4^o and can scan up to ± 14^o with sidelobe levels less than -15 dB.Another phase shifter reducing method, the interwoven feeding networks, is investigated. These passive feeding networks are composed of power dividers, couplers and resistive attenuators. In this configuration, each phase shifter feeds all of the antennas and creates a sinc-like current distribution over the array elements which results in a boxcar function-like element pattern. This element pattern is used to cancel the grating lobes. By changing the…

Subjects/Keywords: Electrical engineering; Electromagnetics; Beam Forming; Microstrip Antennas; Phased-Arrays; Reconfigurable Antennas; Tunable Antennas

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Avser, B. (2015). Frequency Tunable Antennas and Novel Phased Array Feeding Networks for Next Generation Communication Systems. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/6cq329s4

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Avser, Bilgehan. “Frequency Tunable Antennas and Novel Phased Array Feeding Networks for Next Generation Communication Systems.” 2015. Thesis, University of California – San Diego. Accessed March 05, 2021. http://www.escholarship.org/uc/item/6cq329s4.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Avser, Bilgehan. “Frequency Tunable Antennas and Novel Phased Array Feeding Networks for Next Generation Communication Systems.” 2015. Web. 05 Mar 2021.

Vancouver:

Avser B. Frequency Tunable Antennas and Novel Phased Array Feeding Networks for Next Generation Communication Systems. [Internet] [Thesis]. University of California – San Diego; 2015. [cited 2021 Mar 05]. Available from: http://www.escholarship.org/uc/item/6cq329s4.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Avser B. Frequency Tunable Antennas and Novel Phased Array Feeding Networks for Next Generation Communication Systems. [Thesis]. University of California – San Diego; 2015. Available from: http://www.escholarship.org/uc/item/6cq329s4

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

13. Trinh, Le-Huy. Antennes reconfigurables pour les applications mobiles et réseaux sans fil : Reconfigurable antennas for mobile phone and WSN applications.

Degree: Docteur es, Électronique, 2015, Nice

URL: http://www.theses.fr/2015NICE4047

►

Au cours de ces dernières années, les technologies de télécommunication ont fait d'énormes progrès, notamment dans les communications mobiles et les réseaux de capteurs sans… (more)

▼

Au cours de ces dernières années, les technologies de télécommunication ont fait d'énormes progrès, notamment dans les communications mobiles et les réseaux de capteurs sans fil (WSN). Pour répondre à l’augmentation de la capacité de transmission et à l’amélioration de la qualité des canaux de communications mobiles, l’élargissement de la bande de fonctionnement est nécessaire par l'utilisation d'antennes reconfigurables en fréquence. En outre, dans les applications WSN, afin de réduire les collisions, d’augmenter la distance de communication et d'optimiser la consommation, l’utilisation d’antennes reconfigurables en directivité est une bonne solution. Dans ce cadre, nos travaux de recherche ont portés sur la conception de différentes structures antennaires reconfigurables. Dans un premier temps nous avons réalisés une antenne reconfigurable à base de nouveaux éléments actifs, les digitally tunable capacitors (DTC). Ces composants sont de très bons candidats en vue d’une intégration d'antennes pour des applications communications mobiles et WSN. Ensuite nous nous sommes attachés à concevoir des structures multibande, MIMO et reconfigurables en fréquence, permettant d’augmenter la bande de fréquence de fonctionnement du système de communication, d'optimiser l'efficacité et la qualité spectrale et d'améliorer la qualité de canal. Enfin, une autre voie a été explorée, l’utilisation d’antennes reconfigurables en directivité pour des applications de WSN. Les résultats de simulation et de mesure sont également présentés dans ce chapitre. Grâce à l'utilisation de ce type de structures, la performance des WSN a été optimisée.

In recent years, telecommunication technologies have enormous progress, especially cellular communications and wireless sensor networks. To meet the demand of increasing transmission capacity, improving quality of cellular communication channels, expanding the operating band of the equipment is necessary. As passive antenna has reached the limit on increasing the operating band with the small size, the use of frequency reconfigurable antenna is a feasible solution. Besides, in the applications of WSN, to reduce collisions, increase communication distance and optimize consumption, directional reconfigurable antenna is a good proposal. In this thesis we present several reconfigurable antenna structures. Firstly, a new component is introduced; digitally tunable capacitor (DTC). Thanks to its advantages, such parts are good candidate to be integrated in the antenna for cellular communication and wireless sensor network applications. After, several antennas are introduced include multiband antenna, MIMO and frequency reconfigurable antenna, which can be used to extend the operating frequency band of the communication system, optimize spectral efficiency and quality improve channel quality. The structures of these antennas are introduced together with the results of simulation and measurement for the purpose of solving the challenges given in the future cellular communications systems. And then, the…

Advisors/Committee Members: Ribero, Jean-Marc (thesis director).

Subjects/Keywords: Antennes reconfigurables; Antennes WSE; Antennes LTE; 5G; Reconfigurable antennas; WSE antennas; LTE antennas; 5G

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APA (6^th Edition):

Trinh, L. (2015). Antennes reconfigurables pour les applications mobiles et réseaux sans fil : Reconfigurable antennas for mobile phone and WSN applications. (Doctoral Dissertation). Nice. Retrieved from http://www.theses.fr/2015NICE4047

Chicago Manual of Style (16^th Edition):

Trinh, Le-Huy. “Antennes reconfigurables pour les applications mobiles et réseaux sans fil : Reconfigurable antennas for mobile phone and WSN applications.” 2015. Doctoral Dissertation, Nice. Accessed March 05, 2021. http://www.theses.fr/2015NICE4047.

MLA Handbook (7^th Edition):

Trinh, Le-Huy. “Antennes reconfigurables pour les applications mobiles et réseaux sans fil : Reconfigurable antennas for mobile phone and WSN applications.” 2015. Web. 05 Mar 2021.

Vancouver:

Trinh L. Antennes reconfigurables pour les applications mobiles et réseaux sans fil : Reconfigurable antennas for mobile phone and WSN applications. [Internet] [Doctoral dissertation]. Nice; 2015. [cited 2021 Mar 05]. Available from: http://www.theses.fr/2015NICE4047.

Council of Science Editors:

Trinh L. Antennes reconfigurables pour les applications mobiles et réseaux sans fil : Reconfigurable antennas for mobile phone and WSN applications. [Doctoral Dissertation]. Nice; 2015. Available from: http://www.theses.fr/2015NICE4047

University of New Mexico

14. Vijayamohanan, Jayakrishnan. DESIGN AND FABRICATION OF PEEL-OFF AND STICK ANTENNAS.

Degree: Electrical and Computer Engineering, 2019, University of New Mexico

URL: https://digitalrepository.unm.edu/ece_etds/465

► Antennas on multiple platforms with the capability to be reused is a novel concept in antenna technologies. This thesis explores the idea of such… (more)

Subjects/Keywords: Peel-off Antennas; Microstrip Antennas; Electrically Small Antennas; Reconfigurable antennas; Adhesives; Log Periodic Dipole Arrays; Reconfigurable Antennas; Antenna miniaturization; Electrical and Computer Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vijayamohanan, J. (2019). DESIGN AND FABRICATION OF PEEL-OFF AND STICK ANTENNAS. (Masters Thesis). University of New Mexico. Retrieved from https://digitalrepository.unm.edu/ece_etds/465

Chicago Manual of Style (16^th Edition):

Vijayamohanan, Jayakrishnan. “DESIGN AND FABRICATION OF PEEL-OFF AND STICK ANTENNAS.” 2019. Masters Thesis, University of New Mexico. Accessed March 05, 2021. https://digitalrepository.unm.edu/ece_etds/465.

MLA Handbook (7^th Edition):

Vijayamohanan, Jayakrishnan. “DESIGN AND FABRICATION OF PEEL-OFF AND STICK ANTENNAS.” 2019. Web. 05 Mar 2021.

Vancouver:

Vijayamohanan J. DESIGN AND FABRICATION OF PEEL-OFF AND STICK ANTENNAS. [Internet] [Masters thesis]. University of New Mexico; 2019. [cited 2021 Mar 05]. Available from: https://digitalrepository.unm.edu/ece_etds/465.

Council of Science Editors:

Vijayamohanan J. DESIGN AND FABRICATION OF PEEL-OFF AND STICK ANTENNAS. [Masters Thesis]. University of New Mexico; 2019. Available from: https://digitalrepository.unm.edu/ece_etds/465

NSYSU

15. Hsieh, Yi-ting. LTE/WWAN Ground Antenna for Slim Handheld Communication Devices.

Degree: Master, Electrical Engineering, 2013, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0510113-101908

► In this thesis, a ground antenna is presented for applications in slim handheld communication devices to cover LTE/WWAN operation. The antenna has a very small… (more)

Subjects/Keywords: Reconfigurable antennas; Ground antennas; Switchable antennas; Wideband matching circuit; LTE/WWAN antennas; Small antenna; Specific absorption rate

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APA (6^th Edition):

Hsieh, Y. (2013). LTE/WWAN Ground Antenna for Slim Handheld Communication Devices. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0510113-101908

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hsieh, Yi-ting. “LTE/WWAN Ground Antenna for Slim Handheld Communication Devices.” 2013. Thesis, NSYSU. Accessed March 05, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0510113-101908.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hsieh, Yi-ting. “LTE/WWAN Ground Antenna for Slim Handheld Communication Devices.” 2013. Web. 05 Mar 2021.

Vancouver:

Hsieh Y. LTE/WWAN Ground Antenna for Slim Handheld Communication Devices. [Internet] [Thesis]. NSYSU; 2013. [cited 2021 Mar 05]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0510113-101908.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hsieh Y. LTE/WWAN Ground Antenna for Slim Handheld Communication Devices. [Thesis]. NSYSU; 2013. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0510113-101908

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

16. Nishamol, M S. Design and Development of re configurable compact cross patch antenna for switchable polarization.

Degree: Electronics, 2012, Cochin University of Science and Technology

URL: http://dyuthi.cusat.ac.in/purl/3085

►

Antennas are necessary and vital components of communication and radar systems, but sometimes their inability to adjust to new operating scenarios can limit system performance.… (more)

Subjects/Keywords: Microstrip antennas; Various Microstrip antennas; Feeding Techniques; Reconfigurable antennas; Dual- frequency microstrip antennas; Antenna measurement facilities

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Nishamol, M. S. (2012). Design and Development of re configurable compact cross patch antenna for switchable polarization. (Thesis). Cochin University of Science and Technology. Retrieved from http://dyuthi.cusat.ac.in/purl/3085

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Nishamol, M S. “Design and Development of re configurable compact cross patch antenna for switchable polarization.” 2012. Thesis, Cochin University of Science and Technology. Accessed March 05, 2021. http://dyuthi.cusat.ac.in/purl/3085.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Nishamol, M S. “Design and Development of re configurable compact cross patch antenna for switchable polarization.” 2012. Web. 05 Mar 2021.

Vancouver:

Nishamol MS. Design and Development of re configurable compact cross patch antenna for switchable polarization. [Internet] [Thesis]. Cochin University of Science and Technology; 2012. [cited 2021 Mar 05]. Available from: http://dyuthi.cusat.ac.in/purl/3085.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Nishamol MS. Design and Development of re configurable compact cross patch antenna for switchable polarization. [Thesis]. Cochin University of Science and Technology; 2012. Available from: http://dyuthi.cusat.ac.in/purl/3085

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Macquarie University

17. Simorangkir, Roy Bachtiar Van Basten. Polydimethylsiloxane-embedded conductive fabric for realisation of robust flexible passive and active wearable antennas.

Degree: 2018, Macquarie University

URL: http://hdl.handle.net/1959.14/1265456

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Theoretical thesis.

Bibliography: pages 127-142.

1. Introduction – 2. PDMS-embedded conductive fabric – 3. Simple dual-band dual-mode wearable antenna based on PDMS-embedded conductive fabric –… (more)

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Theoretical thesis.

Bibliography: pages 127-142.

1. Introduction – 2. PDMS-embedded conductive fabric – 3. Simple dual-band dual-mode wearable antenna based on PDMS-embedded conductive fabric – 4. UWB wearable antenna with full ground plane based on PDMS embedded conductive fabric – 5. Realising robust flexible electronically tunable antennas using PDMS embedded conductive fabric – 6. Conclusions and future work – Bibliography.

This thesis presents polydimethylsiloxane (PDMS)-embedded conductive fabric as a new approach to realise robust flexible wearable antennas. The approach combines the use of conductive fabric as the antenna radiator and ground plane, with PDMS which acts as the antenna substrate and a protective encapsulation. This allows for a simple yet effective approach to achieve robust flexible wearable antennas.

Initially, a thorough characterisation of the mechanical and electrical properties of the PDMS-embedded conductive fabric was demonstrated with four potential combinations of PDMS-conductive fabric considered in this thesis. This characterisation provides valuable insight into the mechanical robustness of the proposed approach, the constraints associated with selection of the conductive fabric for various parts of the antenna, and the effective modelling of the antenna. Upon gathering the characterisation results, several wearable antenna designs were developed as concept demonstrations. To verify the designs, their performance was then investigated experimentally, including RF performance tests both in free space and on fabricated ultra-wideband (UWB) human-muscle equivalent phantoms, and mechanical stability tests e.g. bending tests on the aforementioned phantoms and machine-washing tests.

As the first concept demonstration, four simple inset-fed rectangular patches were designed using the four combinations of PDMS-conductive fabric characterised before, thus verifying the properties obtained from the characterisation process. Next, a new dual-band dual-mode antenna design suitable for off- and on-body communication was developed as the second demonstration. Different from previously reported works, the dual-band dual-mode operation was achieved by utilising inherently generated higher order modes of a patch antenna, allowing for a much simpler design that only used a single patch fed by a simple probe feed.

Further, a novel planar UWB antenna design was developed to demonstrate the applicability of the PDMS-embedded conductive fabric technique for UWB and high-frequency applications. In contrast to previously reported flexible UWB antennas, the design maintains a full ground plane which provides a high isolation between the antenna and the human body when worn. The antenna time-domain analysis in both free-space and on-body environments was also conducted, demonstrating its suitability for UWB pulse transmission.

Lastly, the application of PDMS-embedded conductive-fabric technology was expanded further to cover, for the first time, the realisation of robust…

Advisors/Committee Members: Macquarie University. School of Engineering.

Subjects/Keywords: Antennas (Electronics) – Design and construction; Polydimethylsiloxane; conductive fabric; dual-band; flexible antennas; microstrip antennas; polydimethylsiloxane; polymer composite; reconfigurable; wearable

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Simorangkir, R. B. V. B. (2018). Polydimethylsiloxane-embedded conductive fabric for realisation of robust flexible passive and active wearable antennas. (Doctoral Dissertation). Macquarie University. Retrieved from http://hdl.handle.net/1959.14/1265456

Chicago Manual of Style (16^th Edition):

Simorangkir, Roy Bachtiar Van Basten. “Polydimethylsiloxane-embedded conductive fabric for realisation of robust flexible passive and active wearable antennas.” 2018. Doctoral Dissertation, Macquarie University. Accessed March 05, 2021. http://hdl.handle.net/1959.14/1265456.

MLA Handbook (7^th Edition):

Simorangkir, Roy Bachtiar Van Basten. “Polydimethylsiloxane-embedded conductive fabric for realisation of robust flexible passive and active wearable antennas.” 2018. Web. 05 Mar 2021.

Vancouver:

Simorangkir RBVB. Polydimethylsiloxane-embedded conductive fabric for realisation of robust flexible passive and active wearable antennas. [Internet] [Doctoral dissertation]. Macquarie University; 2018. [cited 2021 Mar 05]. Available from: http://hdl.handle.net/1959.14/1265456.

Council of Science Editors:

Simorangkir RBVB. Polydimethylsiloxane-embedded conductive fabric for realisation of robust flexible passive and active wearable antennas. [Doctoral Dissertation]. Macquarie University; 2018. Available from: http://hdl.handle.net/1959.14/1265456

Utah State University

18. Tanagardi, Mehmet. Radiation Pattern Reconfigurable Horn Antenna Based on Parasitic Layer Concept.

Degree: MS, Electrical and Computer Engineering, 2019, Utah State University

URL: https://digitalcommons.usu.edu/etd/7623

► In recent years, multi-functional reconfigurable antennas (MRA) has attracted much attention in wireless communication. The reconfigurable antenna can adapt itself with changing system conditions,… (more)

Subjects/Keywords: Antenna radiation patterns; horn antennas; beam steering; parasitic antennas; multi-functional reconfigurable antennas (MRAs); Electrical and Computer Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tanagardi, M. (2019). Radiation Pattern Reconfigurable Horn Antenna Based on Parasitic Layer Concept. (Masters Thesis). Utah State University. Retrieved from https://digitalcommons.usu.edu/etd/7623

Chicago Manual of Style (16^th Edition):

Tanagardi, Mehmet. “Radiation Pattern Reconfigurable Horn Antenna Based on Parasitic Layer Concept.” 2019. Masters Thesis, Utah State University. Accessed March 05, 2021. https://digitalcommons.usu.edu/etd/7623.

MLA Handbook (7^th Edition):

Tanagardi, Mehmet. “Radiation Pattern Reconfigurable Horn Antenna Based on Parasitic Layer Concept.” 2019. Web. 05 Mar 2021.

Vancouver:

Tanagardi M. Radiation Pattern Reconfigurable Horn Antenna Based on Parasitic Layer Concept. [Internet] [Masters thesis]. Utah State University; 2019. [cited 2021 Mar 05]. Available from: https://digitalcommons.usu.edu/etd/7623.

Council of Science Editors:

Tanagardi M. Radiation Pattern Reconfigurable Horn Antenna Based on Parasitic Layer Concept. [Masters Thesis]. Utah State University; 2019. Available from: https://digitalcommons.usu.edu/etd/7623

19. Jaeck, Vincent. Développement d’antennes de communication reconfigurables en bande C pour munitions intelligentes : Development of reconfigurable communication antennas in C band for smart ammunition.

Degree: Docteur es, Électronique, 2016, Rennes 1

URL: http://www.theses.fr/2016REN1S104

►

De nos jours, les communications sans fil sont devenues un moyen incontournable et universel d'échange d'un large éventail d'informations entre différents systèmes, certains d'entre eux… (more)

▼

De nos jours, les communications sans fil sont devenues un moyen incontournable et universel d'échange d'un large éventail d'informations entre différents systèmes, certains d'entre eux étant en mouvement comme des drones parmi tant d'autres. Dans le contexte de cette thèse nous considérons une liaison entre un projectile et une station de base. La géométrie de la structure ainsi que les contraintes aérodynamiques d'un tir balistique impliquent l'utilisation d'antennes patchs dans la partie conique à l'avant du projectile. Ce type d'antenne est facile à intégrer à une plate-forme en tant que réseau conformé tout en respectant les contraintes d'encombrement. Ces communications doivent être fiables et discrètes dans un environnement perturbé ou hostile. Les diagrammes de rayonnement du réseau d'antennes doivent présenter des caractéristiques spécifiques, notamment dans le cas particulier d'objets volants et possédant une rotation en roulis (rotation autour de son axe) qui impliquent l'utilisation d'un réseau phasé et commuté par rapport à sa position. Une antenne qui présenterait un rayonnement fixe assurerait une liaison avec un interlocuteur, mais rayonnerait également dans d'autres directions sensibles ce qui pourraient interférer avec la communication principale. La solution qui consiste à activer et désactiver des sous-réseaux verticaux afin d'orienter le lobe principal dans la plan orthogonal à la pointe semble être en accord avec les contraintes de la structure tournante. Un réseau conique a été étudié puis 2 prototypes ont été fabriqués, dont un à l'ISL. Les sous-réseaux sont répartis de manière égale autour de la pointe de façon à pouvoir rayonner dans toutes les directions. De plus, chaque sous-réseau est composé de trois éléments ce qui permet d'orienter également le lobe principal dans le plan longitudinal de la pointe (le long de l'axe du projectile) grâce à un dépointage électronique. Un système électronique de formation de faisceaux a été développé dans le but de contrôler 12 éléments rayonnants. Le réseau d'antennes ainsi que le circuit de répartition ont été caractérisés dans un premier temps de manière indépendante afin d'optimiser les lois de phase nécessaires à dépointer le lobe à partir des pondérations mesurées. Au final, le réseau de 12 éléments associé à son système d'alimentation dédié a été mesuré dans les chambres anéchoïques de DGA-MI et de l'ISL et les mesures sont en accord avec les simulations.

Nowadays wireless communications have become a useful and universal mean to exchange a wide range of information between different systems, some of them being moving, as UAVs among others. In this context we consider here the link between a projectile and a base station. The shape of the structure and the aerodynamic constraints involve the use of patch antennas in the conical front part. This class of antenna is easy to be integrated into the platform as a conformal array, while respecting space constraint. Communications have to be reliable and discrete in disturbed or hostile environment.…

Advisors/Committee Members: Mahdjoubi, Kouroch (thesis director), Sauleau, Ronan (thesis director).

Subjects/Keywords: Antennes reconfigurables; Antennes réseaux; Réseaux phasés; Reconfigurable antennas; Antenna arrays

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jaeck, V. (2016). Développement d’antennes de communication reconfigurables en bande C pour munitions intelligentes : Development of reconfigurable communication antennas in C band for smart ammunition. (Doctoral Dissertation). Rennes 1. Retrieved from http://www.theses.fr/2016REN1S104

Chicago Manual of Style (16^th Edition):

Jaeck, Vincent. “Développement d’antennes de communication reconfigurables en bande C pour munitions intelligentes : Development of reconfigurable communication antennas in C band for smart ammunition.” 2016. Doctoral Dissertation, Rennes 1. Accessed March 05, 2021. http://www.theses.fr/2016REN1S104.

MLA Handbook (7^th Edition):

Jaeck, Vincent. “Développement d’antennes de communication reconfigurables en bande C pour munitions intelligentes : Development of reconfigurable communication antennas in C band for smart ammunition.” 2016. Web. 05 Mar 2021.

Vancouver:

Jaeck V. Développement d’antennes de communication reconfigurables en bande C pour munitions intelligentes : Development of reconfigurable communication antennas in C band for smart ammunition. [Internet] [Doctoral dissertation]. Rennes 1; 2016. [cited 2021 Mar 05]. Available from: http://www.theses.fr/2016REN1S104.

Council of Science Editors:

Jaeck V. Développement d’antennes de communication reconfigurables en bande C pour munitions intelligentes : Development of reconfigurable communication antennas in C band for smart ammunition. [Doctoral Dissertation]. Rennes 1; 2016. Available from: http://www.theses.fr/2016REN1S104

20. Khidre, Ahmed. Reconfigurable microstrip antennas with tunable radiation pattern characteristics.

Degree: PhD, Electrical Engineering, 2014, University of Mississippi

URL: https://egrove.olemiss.edu/etd/1388

► Reconfigurable beam antenna systems are capable of changing their radiation characteristics in real time, such as beam direction, beam shape, beamwidth, etc. Such antenna system… (more)

▼ Reconfigurable beam antenna systems are capable of changing their radiation characteristics in real time, such as beam direction, beam shape, beamwidth, etc. Such antenna system is desired for various wireless applications because of many reasons among them; it helps to enhance signal strength received from an intended target, mitigates interference, and accommodates sudden changes in traffic demand of wireless networks. It might also help to reduce the deployment cost of wireless networks infrastructures. In this dissertation, designs for reconfigurable beam microstrip antennas with tunable radiation characteristics have been proposed. The method to achieve these designs is the reconfigurable parasitic element (s) of tunable electrical size, placed in close proximity to the driven patch. A tuning mechanism with the aid of Varactor diodes is introduced for the parasitic patch that effectively allows for controlling its electrical size. This (these) reconfigurable parasitic patch (es) is (are) then applied in different fashions to devise several antenna designs with dynamic electronic control over certain radiation specifications. The accomplished antenna designs in the dissertation are: * Circularly polarized (CP) beam scanning antenna, where two elements microstrip Yagi-Uda antenna is used. The first element is a square patch driven with two probe feeds of quadrature phase for CP excitation. The second element is a parasitic square patch with narrow square-shaped slot carved on its surface. The parasitic patch is adjacent to the driven patch with a small separation distance. Four varactor diodes are placed on the middle of each side of the square slot to facilitate tuning of its electrical size. The parasitic patch electrical size is allowed to be effectively tuned by varying the applied reverse biasing DC voltage to the varactors (capacitance value). The CP beam direction is scanned from -36° to 32° with gain variation from 5.7 to 8.2 dBic, and efficiency from 54% to 75.58% along the scanning range. * Two-dimensional beam scanning antenna, where two orthogonal crossed Yagi-Uda antenna configuration is utilized. The driven element is a square patch excited with a probe coaxial feed. The other two parasitic patches are closely placed along the E & H planes of the driven patch. Each parasitic patch has a narrow rectangular slit at its center, where a varactor diode is placed to allow for tuning its electrical size. The beam direction is permitted to be scanned in both the elevation and azimuth planes. The achieved scan range in the elevation plane is from 0° to 32°, whereas in azimuth plan is from 0° to 90°. Along the scanning range, the attained gain changes from 8.1 to 8.9 dBi, and efficiency changes from 86% to 93%. * Tunable beamwidth antenna, with a dynamic control over the radiation beam focusing is proposed. The antenna consists of a square patch excited by a coaxial probe feed, and other two square parasitic patches placed on both sides of the driven along its H-plane. Each parasitic patch has a narrow slit at… Advisors/Committee Members: Fan Yang, Gerrard Buskes, Alexander Yakovlev.

Subjects/Keywords: Antennas; Microstrip; Radiation beam; Reconfigurable; Electromagnetics and Photonics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Khidre, A. (2014). Reconfigurable microstrip antennas with tunable radiation pattern characteristics. (Doctoral Dissertation). University of Mississippi. Retrieved from https://egrove.olemiss.edu/etd/1388

Chicago Manual of Style (16^th Edition):

Khidre, Ahmed. “Reconfigurable microstrip antennas with tunable radiation pattern characteristics.” 2014. Doctoral Dissertation, University of Mississippi. Accessed March 05, 2021. https://egrove.olemiss.edu/etd/1388.

MLA Handbook (7^th Edition):

Khidre, Ahmed. “Reconfigurable microstrip antennas with tunable radiation pattern characteristics.” 2014. Web. 05 Mar 2021.

Vancouver:

Khidre A. Reconfigurable microstrip antennas with tunable radiation pattern characteristics. [Internet] [Doctoral dissertation]. University of Mississippi; 2014. [cited 2021 Mar 05]. Available from: https://egrove.olemiss.edu/etd/1388.

Council of Science Editors:

Khidre A. Reconfigurable microstrip antennas with tunable radiation pattern characteristics. [Doctoral Dissertation]. University of Mississippi; 2014. Available from: https://egrove.olemiss.edu/etd/1388

Utah State University

21. Hasan, Mehedi. Efficient Algorithms for Reconfigurable Antenna Systems.

Degree: PhD, Electrical and Computer Engineering, 2018, Utah State University

URL: https://digitalcommons.usu.edu/etd/7239

► The main goal of this research is to develop algorithms to facilitate the use of a new type of antenna, called multifunctional reconfigurable antenna… (more)

Subjects/Keywords: Reconfigurable Antennas; MRA; RA; Wireless Communication; Electrical and Computer Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hasan, M. (2018). Efficient Algorithms for Reconfigurable Antenna Systems. (Doctoral Dissertation). Utah State University. Retrieved from https://digitalcommons.usu.edu/etd/7239

Chicago Manual of Style (16^th Edition):

Hasan, Mehedi. “Efficient Algorithms for Reconfigurable Antenna Systems.” 2018. Doctoral Dissertation, Utah State University. Accessed March 05, 2021. https://digitalcommons.usu.edu/etd/7239.

MLA Handbook (7^th Edition):

Hasan, Mehedi. “Efficient Algorithms for Reconfigurable Antenna Systems.” 2018. Web. 05 Mar 2021.

Vancouver:

Hasan M. Efficient Algorithms for Reconfigurable Antenna Systems. [Internet] [Doctoral dissertation]. Utah State University; 2018. [cited 2021 Mar 05]. Available from: https://digitalcommons.usu.edu/etd/7239.

Council of Science Editors:

Hasan M. Efficient Algorithms for Reconfigurable Antenna Systems. [Doctoral Dissertation]. Utah State University; 2018. Available from: https://digitalcommons.usu.edu/etd/7239

INP Toulouse

22. Duran Venegas, Juan Antonio. Reconfigurable Metasurfaces for Beam Scanning Planar Antennas : Antennes planaires à métasurfaces reconfigurables pour le balayage électrique du faisceau.

Degree: Docteur es, Electromagnétisme et Systèmes Haute Fréquence, 2016, INP Toulouse

URL: http://www.theses.fr/2016INPT0102

►

Nous étudions la mise en oeuvre d ‘antenne à balayage électronique dédiés aux applications de communications par satellite géostationnaire. Les structures développées sont adaptées pour… (more)

Subjects/Keywords: Métamatériaux actifs; Antennes planaires; CRLH; Antennes à dépointage; Antennes reconfigurables; Active metamaterials; Active metamaterials; CRLH; Scanning antennas; Reconfigurable antennas

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APA (6^th Edition):

Duran Venegas, J. A. (2016). Reconfigurable Metasurfaces for Beam Scanning Planar Antennas : Antennes planaires à métasurfaces reconfigurables pour le balayage électrique du faisceau. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2016INPT0102

Chicago Manual of Style (16^th Edition):

Duran Venegas, Juan Antonio. “Reconfigurable Metasurfaces for Beam Scanning Planar Antennas : Antennes planaires à métasurfaces reconfigurables pour le balayage électrique du faisceau.” 2016. Doctoral Dissertation, INP Toulouse. Accessed March 05, 2021. http://www.theses.fr/2016INPT0102.

MLA Handbook (7^th Edition):

Duran Venegas, Juan Antonio. “Reconfigurable Metasurfaces for Beam Scanning Planar Antennas : Antennes planaires à métasurfaces reconfigurables pour le balayage électrique du faisceau.” 2016. Web. 05 Mar 2021.

Vancouver:

Duran Venegas JA. Reconfigurable Metasurfaces for Beam Scanning Planar Antennas : Antennes planaires à métasurfaces reconfigurables pour le balayage électrique du faisceau. [Internet] [Doctoral dissertation]. INP Toulouse; 2016. [cited 2021 Mar 05]. Available from: http://www.theses.fr/2016INPT0102.

Council of Science Editors:

Duran Venegas JA. Reconfigurable Metasurfaces for Beam Scanning Planar Antennas : Antennes planaires à métasurfaces reconfigurables pour le balayage électrique du faisceau. [Doctoral Dissertation]. INP Toulouse; 2016. Available from: http://www.theses.fr/2016INPT0102

23. Khidre, Ahmed. Reconfigurable Wideband Circulalry Polarized Microstrip Antenna for Wireless Applications.

Degree: M.S. in Engineering Science, Engineering Science, 2012, University of Mississippi

URL: https://egrove.olemiss.edu/etd/164

► In this thesis, developments of rectangular microstrip patch antenna to have circular polarization agility with wideband performance, for wireless applications are presented. First, a new… (more)

▼ In this thesis, developments of rectangular microstrip patch antenna to have circular polarization agility with wideband performance, for wireless applications are presented. First, a new technique to achieve circularly polarized (CP) probe feed single-layer microstrip patch antenna with wideband characteristics is proposed. The antenna is a modified form of the popular E-shaped patch, used to broaden the impedance bandwidth of a basic rectangular patch antenna. This is established by letting the two parallel slots of the E-patch unequal. Thus, by introducing asymmetry two orthogonal currents on the patch are excited and circularly polarized fields are realized. The proposed technique exhibits the advantage of the simplicity inherent in the E-shaped patch design. It requires only slot lengths, widths, and position parameters to be determined. Also, it is suitable for later adding the reconfigurable capability. With the aid of full-wave simulator Ansoft HFSS, investigations on the effect of various dimensions of the antenna have been carried out via parametric analysis. Based on these investigations, a design procedure for a CP E-shaped patch is summarized. Various design examples with different substrate thicknesses and material types are presented and compared, with CP U-slot patch antennas, recently proposed in the literature. A prototype has been constructed following the suggested design procedure to cover the IEEE 802.11b/g WLAN band. The performance of the fabricated antenna was measured and compared with the simulation results for the reflection coefficient, axial ratio, radiation pattern, and antenna gain. Good agreement is achieved between simulation and measured results demonstrating a high gain and wideband performance. Second, a polarization reconfigurable single feed E-shaped patch antenna with wideband performance is proposed. The antenna is capable of switching from right-hand circular polarization (RHCP) to left-hand circular polarization (LHCP) and vice versa, with the aid of two RF PIN diodes that act as RF switches. The proposed structure which is simple; consists of a single-layer single fed radiating E-shaped patch and RF switch placed on each of its slots at an appropriate location. The design targets WLAN IEEE 802.11b/g frequency band (2.4- 2.5 GHz) as one example of the wireless applications. The idea is based on the first proposed design. In other words, if one of the switches is ON and the other is OFF, the two slot lengths will become effectively unequal and circular polarization will be obtained. If the states of the two switches are reversed, circular polarization with opposite orientation will be obtained at the same frequency band. Full-wave simulator Ansoft HFSS is again used for the analysis. Complete detailed DC biasing circuit of the switches for integration with the antenna is presented. Also, characterizations of the microwave components used in the biasing circuit are discussed. Antenna prototype has been fabricated and tested. Simulation results along with the measured one, for… Advisors/Committee Members: Atef Z. Elsherbeni, Alexander B. Yakovlev, Fan Yang.

Subjects/Keywords: Circular Polarization Agility; E-Shaped Patch Antenna; Micostrip Antennas; Reconfigurable Antennas; Rf Pin Diode Switch; Wideband; Electrical and Computer Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Khidre, A. (2012). Reconfigurable Wideband Circulalry Polarized Microstrip Antenna for Wireless Applications. (Thesis). University of Mississippi. Retrieved from https://egrove.olemiss.edu/etd/164

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Khidre, Ahmed. “Reconfigurable Wideband Circulalry Polarized Microstrip Antenna for Wireless Applications.” 2012. Thesis, University of Mississippi. Accessed March 05, 2021. https://egrove.olemiss.edu/etd/164.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Khidre, Ahmed. “Reconfigurable Wideband Circulalry Polarized Microstrip Antenna for Wireless Applications.” 2012. Web. 05 Mar 2021.

Vancouver:

Khidre A. Reconfigurable Wideband Circulalry Polarized Microstrip Antenna for Wireless Applications. [Internet] [Thesis]. University of Mississippi; 2012. [cited 2021 Mar 05]. Available from: https://egrove.olemiss.edu/etd/164.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Khidre A. Reconfigurable Wideband Circulalry Polarized Microstrip Antenna for Wireless Applications. [Thesis]. University of Mississippi; 2012. Available from: https://egrove.olemiss.edu/etd/164

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

24. Lalj, Hicham. Conception et caractérisation de filtres et systèmes antennaires reconfigurables chargés par des résonateurs Métamateriaux sub-longueurs d’onde : Design and characterizationof filters and reconfigurable antenna systems loaded by metamaterial resonators.

Degree: Docteur es, Electronique et télécommunications, 2014, Rennes, INSA

URL: http://www.theses.fr/2014ISAR0022

► Les structures de base de méta-matériaux nourrissent une alternative technologique prometteuse qui vise à répondre à de nouvelles contraintes de miniaturisation et de performances radioélectriques… (more)

▼ Les structures de base de méta-matériaux nourrissent une alternative technologique prometteuse qui vise à répondre à de nouvelles contraintes de miniaturisation et de performances radioélectriques des systèmes reconfigurables à bas coût.Les travaux de cette thèse reposent sur l’association des cellules Métamateriaux unitaires sub-longueurs d’ondes miniatures et agiles, selon des conditions d’excitation électromagnétique en champ proche, à des dispositifs micro-ondes planaires afin de réaliser de nouvelles structures de filtres et de systèmes antennaires reconfigurables.Après une présentation de l’état de l’art, sur à la fois le concept des Métamateriaux micro-ondes et des modèles de filtres et d’antennes à base des Métamateriaux, nos travaux proposent ensuite sur quatre orientations. La première a trait à l’ingénierie de conception et de simulation électromagnétique des cellules unitaires Métamateriaux, ainsi qu’à l’étude de la miniaturisation et de l’agilité des paramètres électriques.La deuxième orientation est consacrée à la réalisation de nouveaux modèles de filtres agiles basés sur le chargement d’une ligne microruban par des résonateurs sub-longueurs d’onde. Deux modèles de filtres sont développés et validés expérimentalement. Le premier concerne un filtre coupe bande basée sur l’association d’une ligne microruban à des résonateurs de type SRR. Selon le même modèle, un filtre passe bande basé sur une ligne microruban associée à deux cellules résonantes à deux fréquences différentes est proposé. Le deuxième modèle concerne un filtre coupe bande à base d’une ligne microruban chargée par des cellules CSRR, une étude de miniaturisation de ce modèle a été présentée et utilise aussi bien l’optimisation des paramètres géométriques qu’électriques ; un facteur de réduction de 5 est obtenu par rapport au filtre coupe bande de base. Les techniques d’agilité étudiées sont basées sur le chargement de la cellule par des éléments électroniques actifs tels que les diodes PIN et Varactor qui sont logés en des positions appropriées. Les résultats obtenus ont montré une variation intéressante des paramètres du filtre en fonction de la tension de polarisation des diodes.La troisième orientation de la thèse vise à introduire de nouveaux modèles d’association en champ proche entre une antenne monopole ULB et des cellules Métamateriaux de type SRR et CSRR. Ces nouveaux modèles ont pour objectif de répondre à des verrous technologiques en termes de reconfigurabilité spectrale tout en préservant le caractère faible encombrement de l’antenne. Le premier modèle proposé concerne une antenne monopole associée à des cellules SRR imprimées sur le substrat à proximité de la ligne d’alimentation de l’antenne. Les résultats théoriques et expérimentaux confirment le comportement coupe bande autour de la fréquence de résonance de la cellule, et une stabilité des performances de rayonnement sur le reste de la bande passante de l’antenne de référence. Pour Le deuxième modèle, le monopole rayonnant est directement chargé par les cellules SRR et… Advisors/Committee Members: Drissi, M'hamed (thesis director).

Subjects/Keywords: Miniaturisation; Agilité; Champ proche; Filtre reconfigurable; Antenne ULB; Système antennaire reconfigurable; Radio cognitive; Split Ring Resonator; Metamaterials; Ultra-wideband antennas; Adaptive antennas; 621.3

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APA (6^th Edition):

Lalj, H. (2014). Conception et caractérisation de filtres et systèmes antennaires reconfigurables chargés par des résonateurs Métamateriaux sub-longueurs d’onde : Design and characterizationof filters and reconfigurable antenna systems loaded by metamaterial resonators. (Doctoral Dissertation). Rennes, INSA. Retrieved from http://www.theses.fr/2014ISAR0022

Chicago Manual of Style (16^th Edition):

Lalj, Hicham. “Conception et caractérisation de filtres et systèmes antennaires reconfigurables chargés par des résonateurs Métamateriaux sub-longueurs d’onde : Design and characterizationof filters and reconfigurable antenna systems loaded by metamaterial resonators.” 2014. Doctoral Dissertation, Rennes, INSA. Accessed March 05, 2021. http://www.theses.fr/2014ISAR0022.

MLA Handbook (7^th Edition):

Lalj, Hicham. “Conception et caractérisation de filtres et systèmes antennaires reconfigurables chargés par des résonateurs Métamateriaux sub-longueurs d’onde : Design and characterizationof filters and reconfigurable antenna systems loaded by metamaterial resonators.” 2014. Web. 05 Mar 2021.

Vancouver:

Lalj H. Conception et caractérisation de filtres et systèmes antennaires reconfigurables chargés par des résonateurs Métamateriaux sub-longueurs d’onde : Design and characterizationof filters and reconfigurable antenna systems loaded by metamaterial resonators. [Internet] [Doctoral dissertation]. Rennes, INSA; 2014. [cited 2021 Mar 05]. Available from: http://www.theses.fr/2014ISAR0022.

Council of Science Editors:

Lalj H. Conception et caractérisation de filtres et systèmes antennaires reconfigurables chargés par des résonateurs Métamateriaux sub-longueurs d’onde : Design and characterizationof filters and reconfigurable antenna systems loaded by metamaterial resonators. [Doctoral Dissertation]. Rennes, INSA; 2014. Available from: http://www.theses.fr/2014ISAR0022

25. Diaby, Fatimata. Réseaux transmetteurs reconfigurables pour le dépointage et la formation de faisceau en bande millimétrique : Reconfigurable transmitarrays for beam-steering and beam -forming at millimeter-waves.

Degree: Docteur es, Optique et radiofrequences, 2018, Université Grenoble Alpes (ComUE)

URL: http://www.theses.fr/2018GREAT125

► De nos jours, les antennes à réseaux transmetteurs attirent un grand intérêt pour de nombreuses applications civiles et militaires aux bandes de fréquence comprises entre… (more)

▼ De nos jours, les antennes à réseaux transmetteurs attirent un grand intérêt pour de nombreuses applications civiles et militaires aux bandes de fréquence comprises entre 10 et 110 GHz (réseaux de communication 5G, liens point à point, radars, etc.).Le travail de thèse vise à faire des innovations dans la modélisation et la conception d'antennes à réseaux transmetteurs pour des applications en bande Ka (28-40 GHz). Il porte plus précisément sur le développement d'outils numériques pour l’analyse théorique des réseaux transmetteurs, la conception et la démonstration de plusieurs prototypes avec des fonctionnalités avancées, telles que des réseaux transmetteurs passifs (larges bandes ou à multifaisceaux) et actifs (à reconfiguration électronique).La première partie des travaux consiste en une analyse théorique des réseaux transmetteurs. Dans un premier temps, l’impact de la méthode de compensation de phase sur les performances des réseaux transmetteurs est étudié. La loi de compensation de phase de l’onde quasi-sphérique incidente sur l’ouverture du réseau transmetteur est calculée en utilisant deux méthodes nommées compensation à phase constante et compensation par ligne à retard, et nous montrons que cette dernière permet d’augmenter la bande passante du réseau transmetteur et de corriger les erreurs de dépointage du faisceau. Dans un second temps, le principe de fonctionnement des réseaux transmetteurs facettés est décrit en détail. La simulation numérique du réseau transmetteur à trois facettes est validée au travers de simulations électromagnétiques 3-D. Pour un certain angle d’inclinaison, nous montrons que la bande passante et la capacité de dépointage du réseau transmetteur sont améliorées au détriment du gain.La suite des travaux porte sur la conception et le prototypage de deux réseaux transmetteurs passifs, dont l’un à faisceau collimaté et très large bande et l’autre à quatre faisceaux fixes. Les deux réseaux transmetteurs sont basés sur une cellule élémentaire à 3bits qui assure une double fonction à savoir la compensation de phase et la conversion de la polarisation linéaire en circulaire. Le réseau passif à faisceau collimaté présente un gain mesuré de 33,8 dBi (correspondant à une efficacité d'ouverture de 51,2%) et une bande passante à -3 dB supérieure à 15,9%. La distribution de phase du réseau transmetteur à quatre faisceaux a été optimisée par un algorithme génétique afin d’avoir des faisceaux dépointés à ± 25° dans le plan horizontal et le plan vertical à la fréquence d’optimisation.La dernière partie des travaux vise la conception d’un réseau transmetteur reconfigurable à 27-31 GHz. Dans un premier temps, une cellule élémentaire active à quatre états de phase (2 bits) en polarisation linéaire a été conçue et validée expérimentalement. Elle est composée de six couches métalliques imprimées sur trois substrats. Les éléments rayonnants sont des antennes patch rectangulaires comprenant chacun deux diodes PIN pour contrôler la phase de transmission. Le principe de fonctionnement de la cellule… Advisors/Committee Members: Dussopt, Laurent (thesis director).

Subjects/Keywords: Antennes à réseau transmetteur; Antennes à dépointage électronique; Antennes reconfigurable; Fréquences millimétriques; Bande Ka; Satcom; Transmittaray antennas; Electronically beam-Steering antenna; Reconfigurable antennas; Millimeter frequencies; Ka-Band; Satcom system; 620

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Diaby, F. (2018). Réseaux transmetteurs reconfigurables pour le dépointage et la formation de faisceau en bande millimétrique : Reconfigurable transmitarrays for beam-steering and beam -forming at millimeter-waves. (Doctoral Dissertation). Université Grenoble Alpes (ComUE). Retrieved from http://www.theses.fr/2018GREAT125

Chicago Manual of Style (16^th Edition):

Diaby, Fatimata. “Réseaux transmetteurs reconfigurables pour le dépointage et la formation de faisceau en bande millimétrique : Reconfigurable transmitarrays for beam-steering and beam -forming at millimeter-waves.” 2018. Doctoral Dissertation, Université Grenoble Alpes (ComUE). Accessed March 05, 2021. http://www.theses.fr/2018GREAT125.

MLA Handbook (7^th Edition):

Diaby, Fatimata. “Réseaux transmetteurs reconfigurables pour le dépointage et la formation de faisceau en bande millimétrique : Reconfigurable transmitarrays for beam-steering and beam -forming at millimeter-waves.” 2018. Web. 05 Mar 2021.

Vancouver:

Diaby F. Réseaux transmetteurs reconfigurables pour le dépointage et la formation de faisceau en bande millimétrique : Reconfigurable transmitarrays for beam-steering and beam -forming at millimeter-waves. [Internet] [Doctoral dissertation]. Université Grenoble Alpes (ComUE); 2018. [cited 2021 Mar 05]. Available from: http://www.theses.fr/2018GREAT125.

Council of Science Editors:

Diaby F. Réseaux transmetteurs reconfigurables pour le dépointage et la formation de faisceau en bande millimétrique : Reconfigurable transmitarrays for beam-steering and beam -forming at millimeter-waves. [Doctoral Dissertation]. Université Grenoble Alpes (ComUE); 2018. Available from: http://www.theses.fr/2018GREAT125

University of California – Irvine

26. Ahmed, Elsayed Ahmed Elsayed. Self-interference Cancellation in Full-duplex Wireless Systems.

Degree: Electrical and Computer Engineering, 2014, University of California – Irvine

URL: http://www.escholarship.org/uc/item/7zh6f8fm

► Due to the tremendous increase in wireless data traffic, one of the major challenges for future wireless systems is the utilization of the available spectrum… (more)

▼ Due to the tremendous increase in wireless data traffic, one of the major challenges for future wireless systems is the utilization of the available spectrum to achieve better data rates over limited spectrum. Currently, systems operate in what is termed "Half Duplex Mode," where they are either transmitting or receiving, but never both using the same temporal and spectral resources. Full-duplex transmission promises to double the spectral efficiency where bidirectional communications is carried out over the same temporal and spectral resources. The main limitation impacting full-duplex transmission is managing the strong self-interference signal imposed by the transmit antenna on the receive antenna within the same transceiver. Several recent publications have demonstrated that the key challenge in practical full-duplex systems is un-cancelled self-interference power caused by a combination of hardware imperfections, especially Radio Frequency (RF) circuits' impairments. In this thesis, we consider the problem of self-interference cancellation in full-duplex systems. The ultimate goal of this work is to design and build a complete, real-time, full-duplex system that is capable of achieving wireless full-duplex transmission using practical hardware platforms. Since RF circuits' impairments are shown to have significant impact on the self-interference cancellation performance, first, we present a thorough analysis of the effect of RF impairments on the cancellation performance, with the aim of identifying the main performance limiting factors and bottlenecks. Second, the thesis proposes several impairments mitigation techniques to improve the overall self-interference cancellation capability by mitigating most of the transceiver RF impairments. In addition to impairments mitigation, two novel full-duplex transceiver architectures that achieve significant self-interference cancellation performance are proposed. The performance of the proposed techniques is analytically and experimentally investigated in practical wireless environments. Finally, the proposed self-interference cancellation techniques are used to build a complete full-duplex system with a 90% experimentally proven full-duplex rate improvement compared to half-duplex systems.

Subjects/Keywords: Engineering; Full duplex; Interference Mitigation; Reconfigurable antennas; Self-interference Cancellation; wireless systems

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ahmed, E. A. E. (2014). Self-interference Cancellation in Full-duplex Wireless Systems. (Thesis). University of California – Irvine. Retrieved from http://www.escholarship.org/uc/item/7zh6f8fm

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ahmed, Elsayed Ahmed Elsayed. “Self-interference Cancellation in Full-duplex Wireless Systems.” 2014. Thesis, University of California – Irvine. Accessed March 05, 2021. http://www.escholarship.org/uc/item/7zh6f8fm.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ahmed, Elsayed Ahmed Elsayed. “Self-interference Cancellation in Full-duplex Wireless Systems.” 2014. Web. 05 Mar 2021.

Vancouver:

Ahmed EAE. Self-interference Cancellation in Full-duplex Wireless Systems. [Internet] [Thesis]. University of California – Irvine; 2014. [cited 2021 Mar 05]. Available from: http://www.escholarship.org/uc/item/7zh6f8fm.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ahmed EAE. Self-interference Cancellation in Full-duplex Wireless Systems. [Thesis]. University of California – Irvine; 2014. Available from: http://www.escholarship.org/uc/item/7zh6f8fm

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

UCLA

27. Kovitz, Joshua. Innovative Antenna Designs for Broadband Circularly-Polarized Wireless Systems and Software Radios.

Degree: Electrical Engineering, 2015, UCLA

URL: http://www.escholarship.org/uc/item/42s6d13c

► Sustaining current increases in wireless data rates has driven engineers of all related backgrounds to seek fresh and innovative approaches in wireless system design. With… (more)

▼ Sustaining current increases in wireless data rates has driven engineers of all related backgrounds to seek fresh and innovative approaches in wireless system design. With the advancement of RF switching technology, transceiver architectures, and digital signal processing capabilities, the pressure now falls on the antenna designs for future broadband and adaptive wireless services. The ﬁrst part of the work focuses on enhancing the bandwidth of low-proﬁle patch antennas for circularly-polarized (CP) wireless systems. We start with an in-depth examination of the CP patch antenna cavity model and reveal that traditional circularly polarized (CP) patch antennas are not being utilized to their full potential for bandwidth. Some new modiﬁcations to enable broader bandwidths are proposed. A high-performance antenna for future Mars Rover missions is also discussed, and a novel CP Half E-shaped patch antenna subarray was developed and prototyped to demonstrate its use. Another concept uses composite right/left-handed (CRLH) transmission lines towards creating wideband CP arrays. Our resulting array prototype using a CRLH transmission line feed network showed an overall bandwidth of 60%, which is a formidable increase compared to designs using conventional quarter-wavelength transmission lines.In the second part of this work, reconﬁgurable antenna functionalities for software and cognitive radios are pursued. With the development of practical reconﬁgurable antenna simulation models in conjunction with nature-inspired optimization techniques, two reconﬁgurable E-shaped patch antenna implementations are evaluated for potential use as frequency or polarization reconﬁgurable antennas. This is particularly useful for systems wanting to achieve unidirectional patterns with a low-proﬁle antenna. Both the frequency and polarization reconﬁgurable designs were optimized, fabricated, and characterized through measurement. Our frequency reconﬁgurable E-shaped patch antenna design is able to support an overall bandwidth of 50% by incorporating MEMS switches. The CP reconﬁgurable version design provided CP bandwidths of 17% and 20% for an element and array concept, respectively. Lastly, a rejection reconﬁgurable array element is developed. The design uses a reconﬁgurable frequency rejection slot within a wideband monopole antenna, and some simulation and experimental measurement studies are undertaken. By integrating another reconﬁgurable ﬁlter, a higher-order ﬁlter capability is achieved, leading to stronger rejection levels from strong blockers.

Subjects/Keywords: Electromagnetics; Electrical engineering; antennas; circular polarization; cognitive radio; reconfigurable; software-defined radio; wideband

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kovitz, J. (2015). Innovative Antenna Designs for Broadband Circularly-Polarized Wireless Systems and Software Radios. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/42s6d13c

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kovitz, Joshua. “Innovative Antenna Designs for Broadband Circularly-Polarized Wireless Systems and Software Radios.” 2015. Thesis, UCLA. Accessed March 05, 2021. http://www.escholarship.org/uc/item/42s6d13c.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kovitz, Joshua. “Innovative Antenna Designs for Broadband Circularly-Polarized Wireless Systems and Software Radios.” 2015. Web. 05 Mar 2021.

Vancouver:

Kovitz J. Innovative Antenna Designs for Broadband Circularly-Polarized Wireless Systems and Software Radios. [Internet] [Thesis]. UCLA; 2015. [cited 2021 Mar 05]. Available from: http://www.escholarship.org/uc/item/42s6d13c.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kovitz J. Innovative Antenna Designs for Broadband Circularly-Polarized Wireless Systems and Software Radios. [Thesis]. UCLA; 2015. Available from: http://www.escholarship.org/uc/item/42s6d13c

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Penn State University

28. Gregory, Micah Dennis. New Methods in Ultra-Wideband Array Design and Finite-Difference Time-Domain Modeling of Memristive Devices.

Degree: 2013, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/19084

► This dissertation covers two electromagnetics topics, the first is the design of ultra-wideband antenna array layouts. The second is the design of reconfigurable radio frequency… (more)

▼ This dissertation covers two electromagnetics topics, the first is the design of ultra-wideband antenna array layouts. The second is the design of reconfigurable radio frequency devices with a newly discovered circuit element, the memristor. The two concepts are seemingly unrelated, however, reconfigurable devices are often used in antennas with multi-band abilities, sometimes switching between frequencies that can be octaves apart. In order to efficiently use these reconfigurable antennas in phased arrays they must be placed in a proper layout, the focus of the first topic. The primary focus of the first topic is the elimination of grating lobes and minimization of peak sidelobe levels in the radiation pattern of antenna arrays. The occurrence of grating lobes in array factors is very similar to aliasing in a digital system when the sampling frequency is below twice the maximum frequency content (i.e. the Nyquist frequency). These lobes appear in the array factor or radiation pattern of periodic arrays when the distance between elements becomes greater than one wavelength (for an unsteered array, and less for a steered phased array), resulting in radiation and reception in undesired directions. Strong mutual coupling negatively affects antenna performance when elements are placed less than a half-wavelength apart, limiting the closest that common antenna elements can be placed. These two phenomena generally limit the usable frequency bandwidth of conventional periodic array systems to about 2:1. As many emerging radio frequency systems that utilize multiple frequencies and ultra-wide bandwidths require high directivity, the need for capable array layout designs becomes apparent. The goal of this portion of research is the creation of design techniques which are capable of readily producing array layouts which yield no grating lobes and low sidelobe levels over vary large frequency bandwidths. The second focus involves a new type of electronic device called the memristor. Their existence was speculated by Leon Chua in the 1970s as the fourth basic circuit element which relates flux to charge. The result is a passive component with a charge or flux dependent resistance, allowing for design of interesting reconfigurable electromagnetic devices without active circuit elements such as transistors. It has received significant interest after a research team at Hewlett-Packard labs successfully fabricated a device using titanium dioxide and platinum which exhibits properties that can be modeled by a memristor. Most excitement resides around their potential for computer memory applications, however, their properties are also useful for other devices. Many frequency selective surface and antenna structures can have adjustable performance characteristics based on the values of embedded lumped resistor elements. Replacing the resistors with memristors allows reconfigurability without the use of significant controlling circuitry that is usually necessary with other reconfigurable devices such as active parts… Advisors/Committee Members: Douglas Henry Werner, Dissertation Advisor/Co-Advisor, Douglas Henry Werner, Committee Chair/Co-Chair, Ram Mohan Narayanan, Committee Member, Douglas Edward Wolfe, Committee Member, Jack Brenizer Jr., Committee Member, Victor P Pasko, Committee Member.

Subjects/Keywords: Ultra-Wideband Array; CMA-ES; Optimization; Aperiodic Arrays; Memristor; Reconfigurable Antennas; Finite-Difference Time-Domain

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gregory, M. D. (2013). New Methods in Ultra-Wideband Array Design and Finite-Difference Time-Domain Modeling of Memristive Devices. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/19084

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gregory, Micah Dennis. “New Methods in Ultra-Wideband Array Design and Finite-Difference Time-Domain Modeling of Memristive Devices.” 2013. Thesis, Penn State University. Accessed March 05, 2021. https://submit-etda.libraries.psu.edu/catalog/19084.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gregory, Micah Dennis. “New Methods in Ultra-Wideband Array Design and Finite-Difference Time-Domain Modeling of Memristive Devices.” 2013. Web. 05 Mar 2021.

Vancouver:

Gregory MD. New Methods in Ultra-Wideband Array Design and Finite-Difference Time-Domain Modeling of Memristive Devices. [Internet] [Thesis]. Penn State University; 2013. [cited 2021 Mar 05]. Available from: https://submit-etda.libraries.psu.edu/catalog/19084.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gregory MD. New Methods in Ultra-Wideband Array Design and Finite-Difference Time-Domain Modeling of Memristive Devices. [Thesis]. Penn State University; 2013. Available from: https://submit-etda.libraries.psu.edu/catalog/19084

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

29. Makdissy, Tony. Nouvelles topologies de cellules déphaseuses à coût et complexité réduits pour les antennes réseaux réflecteurs large bande : New phase-shifting cells of low cost and reduced complexity for broadband reflectarray antennas.

Degree: Docteur es, Electronique et télécommunications, 2013, Rennes, INSA

URL: http://www.theses.fr/2013ISAR0027

►

Les réseaux réflecteurs imprimés connaissent un fort développement depuis la fin des années 80. Ce type d’antenne offre la possibilité de former des diagrammes de… (more)

▼

Les réseaux réflecteurs imprimés connaissent un fort développement depuis la fin des années 80. Ce type d’antenne offre la possibilité de former des diagrammes de rayonnement complexes avec une relative simplicité, un faible coût de réalisation, de faibles pertes et un volume réduit. Cependant, il souffre encore de quelques défauts : - La non régularité de la géométrie de la cellule sur la surface du réseau, dans le cas d’une antenne passive, peut engendrer des dégradations sur le diagramme de rayonnement, surtout à la transition entre deux géométries extrêmes, lorsqu’un nouveau cycle de phase commence. - Le nombre relativement élevé de composants utilisés pour contrôler la phase de l’onde réfléchie, dans le cas d’une antenne reconfigurable, augmente le coût de fabrication de l’antenne et complexifie le circuit de commande des éléments reconfigurables. - La limitation en bande passante, qui a longtemps cantonné ce type d’antenne à des applications bande étroite, est principalement liée au comportement de la cellule unitaire constitutive du réseau. Dans cette thèse, nous nous intéressons donc à la conception de nouvelles topologies de cellules déphaseuses, passives et surtout reconfigurables, qui permettent, tout en conservant une relative simplicité de réalisation, d’offrir une large bande passante. De plus, le contrôle de la phase, dans le cas des cellules reconfigurables, doit être réalisé avec un nombre réduit de composants afin de respecter la contrainte de faible coût de fabrication.

Microstrip printed reflectarrays experience strong development since the late 80s. This type of antenna has the potential to form complex radiation patterns with relative simplicity, low cost, low losses and low profile. However, it still has some shortcomings: - The non-regularity of the geometry of the cell on the surface of the array, in the case of passive antenna, may cause degradation on the radiation pattern, especially at the transition between two extreme geometries, when a new phase cycle begins. - The high number of components used to control the phase of the reflected wave, in the case of reconfigurable antenna, increases the manufacturing cost of the antenna and complicates the control circuit of the reconfigurable elements. - The limited bandwidth has long confined this type of antenna to narrowband applications and is mainly due to the intrinsic bandwidth of the unit cell. In this thesis, we therefore focus on the design of new, passive and reconfigurable, phase-shifting cells that can provide a wide bandwidth while maintaining a simple implementation. In addition, the control of the phase, in the case of reconfigurable cells, must be made with a reduced number of components in order to comply the constraint of low manufacturing cost.

Advisors/Committee Members: Gillard, Raphaël (thesis director).

Subjects/Keywords: Double polarisation linéaire; Complexité réduit; Large bande; Reconfigurable; Cost control; Phase shifters; Adaptive antennas; 621.3

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Makdissy, T. (2013). Nouvelles topologies de cellules déphaseuses à coût et complexité réduits pour les antennes réseaux réflecteurs large bande : New phase-shifting cells of low cost and reduced complexity for broadband reflectarray antennas. (Doctoral Dissertation). Rennes, INSA. Retrieved from http://www.theses.fr/2013ISAR0027

Chicago Manual of Style (16^th Edition):

Makdissy, Tony. “Nouvelles topologies de cellules déphaseuses à coût et complexité réduits pour les antennes réseaux réflecteurs large bande : New phase-shifting cells of low cost and reduced complexity for broadband reflectarray antennas.” 2013. Doctoral Dissertation, Rennes, INSA. Accessed March 05, 2021. http://www.theses.fr/2013ISAR0027.

MLA Handbook (7^th Edition):

Makdissy, Tony. “Nouvelles topologies de cellules déphaseuses à coût et complexité réduits pour les antennes réseaux réflecteurs large bande : New phase-shifting cells of low cost and reduced complexity for broadband reflectarray antennas.” 2013. Web. 05 Mar 2021.

Vancouver:

Makdissy T. Nouvelles topologies de cellules déphaseuses à coût et complexité réduits pour les antennes réseaux réflecteurs large bande : New phase-shifting cells of low cost and reduced complexity for broadband reflectarray antennas. [Internet] [Doctoral dissertation]. Rennes, INSA; 2013. [cited 2021 Mar 05]. Available from: http://www.theses.fr/2013ISAR0027.

Council of Science Editors:

Makdissy T. Nouvelles topologies de cellules déphaseuses à coût et complexité réduits pour les antennes réseaux réflecteurs large bande : New phase-shifting cells of low cost and reduced complexity for broadband reflectarray antennas. [Doctoral Dissertation]. Rennes, INSA; 2013. Available from: http://www.theses.fr/2013ISAR0027

30. Callec, Vincent. Systèmes antennaires reconfigurables pour l'observation spatiale : Reconfigurable antenna systems for space observation.

Degree: Docteur es, Electronique et télécommunications, 2013, Rennes, INSA

URL: http://www.theses.fr/2013ISAR0026

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Cette thèse s’intéresse à la conception d’antennes ultra large bande reconfigurables. Cette étude a été motivée par le souhait de regrouper l’ensemble des antennes d’observation… (more)

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Cette thèse s’intéresse à la conception d’antennes ultra large bande reconfigurables. Cette étude a été motivée par le souhait de regrouper l’ensemble des antennes d’observation présentes sur les satellites en un panneau rayonnant unique afin de pouvoir réduire la taille de ces derniers. Les travaux présentés dans ce mémoire sont donc principalement axés sur la conception d’antennes spirales et sur les améliorations qui peuvent leur être apportées. Ainsi, une nouvelle topologie d’antenne spirale carrée reconfigurable en un réseau de quatre antennes spirales carrées plus petites sur la même ouverture rayonnante est exposée. Cette reconfiguration permet d’augmenter l’efficacité de surface de la structure tout en offrant de nouvelles possibilités d’utilisation à l’antenne et en améliorant ses performances. Les caractéristiques et les performances des deux configurations en états figés sont détaillées. Les maquettes réalisées et les résultats de mesure sont également présentés afin de valider le fonctionnement de l’antenne. Ensuite, différentes améliorations de cette structure sont présentées ainsi qu’une application possible. Enfin, une solution permettant d’améliorer le fonctionnement des antennes spirales imprimées au-dessus d’un plan de masse est décrite. En effet, cette solution permet de supprimer un nul de rayonnement lorsque l’antenne se situe à une demi-longueur d’onde du plan de masse. Sa bande passante d’utilisation peut ainsi être potentiellement doublée sans perdre la moitié de l’énergie comme avec l’utilisation d’absorbants. Cette technique consiste à ajouter un élément rayonnant parasite au-dessus de l’antenne. Cet élément est excité par couplage à l’antenne spirale et rayonne à la fréquence du nul de rayonnement. Cet élément étant faible bande, il ne dégrade pas le fonctionnement de l’antenne aux autres fréquences de la bande passante. Une structure utilisant ce concept a été réalisée afin de valider son fonctionnement.

This thesis focuses on the design of ultrawideband reconfigurable antennas. The objective of this study is to integrate all the antennas of observation on satellites into a single radiating panel and make it reconfigurable. Works presented in this document are focused on the design of spiral antennas and on their possible improvements. Thereby, a new topology of square spiral antenna reconfigurable into an array of four smaller square spiral antennas is shown. This reconfiguration allows increasing the surface efficiency of the structure while offering new possibilities of utilization to the antenna and improving its performance. Characteristics and performance of both configurations in frozen states are presented. Breadboards and measurements are also presented in order to validate the functioning of the antenna. Then, several improvements of this structure are studied and a possible application. Finally, a solution for improving the functioning of spiral antennas printed over a metallic ground plane is presented. This solution permits to remove a null of radiation when the distance…

Advisors/Committee Members: Gillard, Raphaël (thesis director).

Subjects/Keywords: Antennes; Ultra large bande; Reconfigurable; Ultra-wideband antennas; Artificial satellites in remote sensing; 621.382

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APA (6^th Edition):

Callec, V. (2013). Systèmes antennaires reconfigurables pour l'observation spatiale : Reconfigurable antenna systems for space observation. (Doctoral Dissertation). Rennes, INSA. Retrieved from http://www.theses.fr/2013ISAR0026

Chicago Manual of Style (16^th Edition):

Callec, Vincent. “Systèmes antennaires reconfigurables pour l'observation spatiale : Reconfigurable antenna systems for space observation.” 2013. Doctoral Dissertation, Rennes, INSA. Accessed March 05, 2021. http://www.theses.fr/2013ISAR0026.

MLA Handbook (7^th Edition):

Callec, Vincent. “Systèmes antennaires reconfigurables pour l'observation spatiale : Reconfigurable antenna systems for space observation.” 2013. Web. 05 Mar 2021.

Vancouver:

Callec V. Systèmes antennaires reconfigurables pour l'observation spatiale : Reconfigurable antenna systems for space observation. [Internet] [Doctoral dissertation]. Rennes, INSA; 2013. [cited 2021 Mar 05]. Available from: http://www.theses.fr/2013ISAR0026.

Council of Science Editors:

Callec V. Systèmes antennaires reconfigurables pour l'observation spatiale : Reconfigurable antenna systems for space observation. [Doctoral Dissertation]. Rennes, INSA; 2013. Available from: http://www.theses.fr/2013ISAR0026

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