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You searched for subject:(Vertically Coupled). Showing records 1 – 3 of 3 total matches.

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1. Hawatmeh, Derar Fayez. Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters and Embedded Antennas.

Degree: 2018, University of South Florida

The need for miniaturized, and high performance microwave devices has focused significant attention onto new fabrication technologies that can simultaneously achieve high performance and low manufacturing complexity. Additive manufacturing (AM) has proven its capability in fabricating high performance, compact and light weight microwave circuits and antennas, as well as the ability to achieve designs that are complicated to fabricate using other manufacturing approaches. Direct print additive manufacturing (DPAM) is an emerging AM process that combines the fused deposition modeling (FDM) of thermoplastics with micro-dispensing of conductive and insulating pastes. DPAM has the potential to jointly combine high performance and low manufacturing complexity, along with the possibility of real-time tuning. This dissertation aims to leverage the powerful capabilities of DPAM to come-up with new designs and solutions that meet the requirements of rapidly evolving wireless systems and applications. Furthermore, the work in this dissertation provides new techniques and approaches to alleviate the drawbacks and limitations of DPAM fabrication technology. Firstly, the development of 3D packaged antenna, and antenna array are presented along with an analysis of the inherent roughness of 3D printed structures to provide a deeper understanding of the antenna RF performance. The single element presents a new volumetric approach to realizing a 3D half-wave dipole in a packaged format, where it provides the ability to keep a signal distribution network in close proximity to the ground plane, facilitating the implementation of ground connections (e.g. for an active device), mitigating potential surface wave losses, as well as achieving a modest (10.6%) length reduction. In addition, a new approach of implementing conformal antennas using DPAM is presented by printing thin and flexible substrate that can be adhered to 3D structures to facilitate the fabrication and reduce the surface roughness. The array design leverages direct digital manufacturing (DDM) technology to realize a shaped substrate structure that is used to control the array beamwidth. The non-planar substrate allows the element spacing to be changed without affecting the length of the feed network or the distance to the underlying ground plane. The second part describes the first high-Q capacitively-loaded cavity resonator and filter that is compatible with direct print additive manufacturing. The presented design is a compromise between quality factor, cost and manufacturing complexity and to the best of our knowledge is the highest Q-factor resonator demonstrated to date using DPAM compatible materials and processes. The final version of the single resonator achieves a measured unloaded quality factor of 200-325 over the frequency range from 2.0 to 6.5 GHz. The two pole filter is designed using a coupled-resonator approach to operate at 2.44 GHz with 1.9% fractional bandwidth. The presented design approach simplifies evanescent-mode filter fabrication, eliminating…

Subjects/Keywords: 3D-printing; Dipole; Picosecond laser machining; Quality factor; Array; Non-planar; Capacitively-loaded cavity; Evanescent-mode; Stacked structure; Vertically Coupled; Electrical and Computer Engineering; Electromagnetics and Photonics

…Two proposed designs are described; laterally coupled and vertically coupled filters. The… …laterally coupled, and vertically coupled respectively. Both designs present 40.12% and 35.43… …Figure 4.19 Equivalent circuit of n-coupled resonators… …51 Figure 4.20 S21 of two coupled resonators… …54 Figure 4.21 Laterally coupled evanescent-mode cavity filter (all dimensions are in… 

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

APA (6th Edition):

Hawatmeh, D. F. (2018). Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters and Embedded Antennas. (Thesis). University of South Florida. Retrieved from https://scholarcommons.usf.edu/etd/7165

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

Chicago Manual of Style (16th Edition):

Hawatmeh, Derar Fayez. “Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters and Embedded Antennas.” 2018. Thesis, University of South Florida. Accessed April 14, 2021. https://scholarcommons.usf.edu/etd/7165.

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

MLA Handbook (7th Edition):

Hawatmeh, Derar Fayez. “Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters and Embedded Antennas.” 2018. Web. 14 Apr 2021.

Vancouver:

Hawatmeh DF. Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters and Embedded Antennas. [Internet] [Thesis]. University of South Florida; 2018. [cited 2021 Apr 14]. Available from: https://scholarcommons.usf.edu/etd/7165.

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

Council of Science Editors:

Hawatmeh DF. Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters and Embedded Antennas. [Thesis]. University of South Florida; 2018. Available from: https://scholarcommons.usf.edu/etd/7165

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


Ohio University

2. Manoharan, Krishna. Design and Analysis of High-Q, Amorphous Microring Resonator Sensors for Gaseous and Biological Species Detection.

Degree: MS, Electrical Engineering (Engineering and Technology), 2009, Ohio University

The need for biological species and gaseous detection has been increasing over the years with increased amount of pollution and evolving bio-weaponry. Hence an integrated sensor with high sensitivity and selectivity has been identified as very important. In this thesis we propose a design for a vertically coupled optical microring resonator for detecting gaseous and biological agents. An analytical analysis of the design is initially executed using the Marcatili waveguide method and later the design is optimized using Finite Element Methods (FEM). The design involves the optimization of the height, width, ring radius and coupling distance. Different types of losses are identified using analytical methods and their relation with the sensor performance is discussed. The design is finally tuned to achieve high Q. The sensitivity of the design is determined using numerical methods (FEM) and its relationship with Q is discussed. These results are analyzed with respect to fabrication tolerances. This thesis provides a solid background work for designing any microring resonator. Advisors/Committee Members: Whaley, Ralph (Committee Chair).

Subjects/Keywords: Electrical Engineering; Engineering; Optics; Vertically Coupled Microring Resonator; Gaseous Sensor; High Q; Biological Sensor; Integrated Optical Sensors; Amorphous Materials; Micro Ring Resonator; Finite Element Modeling; Marcatili Method; Design; Waveguides

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

APA (6th Edition):

Manoharan, K. (2009). Design and Analysis of High-Q, Amorphous Microring Resonator Sensors for Gaseous and Biological Species Detection. (Masters Thesis). Ohio University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1237489189

Chicago Manual of Style (16th Edition):

Manoharan, Krishna. “Design and Analysis of High-Q, Amorphous Microring Resonator Sensors for Gaseous and Biological Species Detection.” 2009. Masters Thesis, Ohio University. Accessed April 14, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1237489189.

MLA Handbook (7th Edition):

Manoharan, Krishna. “Design and Analysis of High-Q, Amorphous Microring Resonator Sensors for Gaseous and Biological Species Detection.” 2009. Web. 14 Apr 2021.

Vancouver:

Manoharan K. Design and Analysis of High-Q, Amorphous Microring Resonator Sensors for Gaseous and Biological Species Detection. [Internet] [Masters thesis]. Ohio University; 2009. [cited 2021 Apr 14]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1237489189.

Council of Science Editors:

Manoharan K. Design and Analysis of High-Q, Amorphous Microring Resonator Sensors for Gaseous and Biological Species Detection. [Masters Thesis]. Ohio University; 2009. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1237489189

3. Birdwell, Kevin Ray. Wind Regimes in Complex Terrain of the Great Valley of Eastern Tennessee.

Degree: 2011, University of Tennessee – Knoxville

This research was designed to provide an understanding of physical wind mechanisms within the complex terrain of the Great Valley of Eastern Tennessee to assess the impacts of regional air flow with regard to synoptic and mesoscale weather changes, wind direction shifts, and air quality. Meteorological data from 2008–2009 were analyzed from 13 meteorological sites along with associated upper level data. Up to 15 ancillary sites were used for reference. Two-step complete linkage and K-means cluster analyses, synoptic weather studies, and ambient meteorological comparisons were performed to generate hourly wind classifications. These wind regimes revealed seasonal variations of underlying physical wind mechanisms (forced channeled, vertically coupled, pressure-driven, and thermally-driven winds). Synoptic and ambient meteorological analysis (mixing depth, pressure gradient, pressure gradient ratio, atmospheric and surface stability) suggested up to 93% accuracy for the clustered results. Probabilistic prediction schemes of wind flow and wind class change were developed through characterization of flow change data and wind class succession. Data analysis revealed that wind flow in the Great Valley was dominated by forced channeled winds (45–67%) and vertically coupled flow (22–38%). Down-valley pressure-driven and thermally-driven winds also played significant roles (0–17% and 2–20%, respectively), usually accompanied by convergent wind patterns (15–20%) and large wind direction shifts, especially in the Central/Upper Great Valley. The behavior of most wind regimes was associated with detectable pressure differences between the Lower and Upper Great Valley. Mixing depth and synoptic pressure gradients were significant contributors to wind pattern behavior. Up to 15 wind classes and 10 sub-classes were identified in the Central Great Valley with 67 joined classes for the Great Valley at-large. Two-thirds of Great Valley at-large flow was defined by 12 classes. Winds flowed on-axis only 40% of the time. The Great Smoky Mountains helped create down-valley pressure-driven winds, downslope mountain breezes, and divergent air flow. The Cumberland Mountains and Plateau were associated with wind speed reductions in the Central Great Valley, Emory Gap Flow, weak thermally-driven winds, and northwesterly down sloping. Ridge-and-valley terrain enhanced wind direction reversals, pressure-driven winds, as well as locally and regionally produced thermally-driven flow.

Subjects/Keywords: Oak Ridge Reservation; Complex Terrain Meteorology; Pressure-Driven Channeling; Thermally-Driven Winds; Vertically Coupled; Wind Reversals; Atmospheric Sciences; Climate; Environmental Health and Protection; Environmental Indicators and Impact Assessment; Environmental Monitoring; Meteorology

…channeled, vertically coupled, pressure-driven, and thermally-driven winds). Synoptic and… …5 1.2.1.3 Vertically Coupled Flow… …104 3.2.2 Vertically Coupled Flow (VCF)… …143 3.4.2 Vertically Coupled Flow (VCF)… …153 3.5.2 Vertically Coupled Flow (VCF)… 

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

APA (6th Edition):

Birdwell, K. R. (2011). Wind Regimes in Complex Terrain of the Great Valley of Eastern Tennessee. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/950

Chicago Manual of Style (16th Edition):

Birdwell, Kevin Ray. “Wind Regimes in Complex Terrain of the Great Valley of Eastern Tennessee.” 2011. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed April 14, 2021. https://trace.tennessee.edu/utk_graddiss/950.

MLA Handbook (7th Edition):

Birdwell, Kevin Ray. “Wind Regimes in Complex Terrain of the Great Valley of Eastern Tennessee.” 2011. Web. 14 Apr 2021.

Vancouver:

Birdwell KR. Wind Regimes in Complex Terrain of the Great Valley of Eastern Tennessee. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2011. [cited 2021 Apr 14]. Available from: https://trace.tennessee.edu/utk_graddiss/950.

Council of Science Editors:

Birdwell KR. Wind Regimes in Complex Terrain of the Great Valley of Eastern Tennessee. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2011. Available from: https://trace.tennessee.edu/utk_graddiss/950

.