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Universidad de Cantabria
1.
Elvira Arregui, Víctor.
Baseband Processing in Analog Combining MIMO Systems: From Theoretical Design to FPGA Implementation: Procesado Banda Base en sistemas MIMO basados en combinación analógica de antenas : del diseño teórico a la implementación FPGA : tesis doctoral.
Degree: 2011, Universidad de Cantabria
URL: http://hdl.handle.net/10902/1343 
► ABSTRACT: In this thesis, we consider an analog antenna combining architecture for a MIMO wireless transceiver, while pointing out its advantages with respect to the…
(more)
▼ ABSTRACT: In this thesis, we consider an analog antenna combining architecture for a MIMO
wireless transceiver, while pointing out its advantages with respect to the traditional MIMO architectures. In the first part of this work, we focus on the transceiver design, especially the calculation of the beamformers that must be applied at the RF. This analysis is performed in an OFDM system under different assumptions on the channel state information. As a result, several criteria and algorithms for the selection of the beamformers are proposed. In the second part, we address the FPGA design and implementation of a baseband processor for this architecture. This baseband processor is based on the standard IEEE 802.11a. Finally, some real-time tests of the implemented baseband processor are carried out both in stand-alone configuration and also with the whole physical layer setup.
Advisors/Committee Members: Ibáñez Díaz, Jesús María (advisor), Universidad de Cantabria (other).
Subjects/Keywords: Wireless communications
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APA (6th Edition):
Elvira Arregui, V. (2011). Baseband Processing in Analog Combining MIMO Systems: From Theoretical Design to FPGA Implementation: Procesado Banda Base en sistemas MIMO basados en combinación analógica de antenas : del diseño teórico a la implementación FPGA : tesis doctoral. (Doctoral Dissertation). Universidad de Cantabria. Retrieved from http://hdl.handle.net/10902/1343
Chicago Manual of Style (16th Edition):
Elvira Arregui, Víctor. “Baseband Processing in Analog Combining MIMO Systems: From Theoretical Design to FPGA Implementation: Procesado Banda Base en sistemas MIMO basados en combinación analógica de antenas : del diseño teórico a la implementación FPGA : tesis doctoral.” 2011. Doctoral Dissertation, Universidad de Cantabria. Accessed March 04, 2021.
http://hdl.handle.net/10902/1343.
MLA Handbook (7th Edition):
Elvira Arregui, Víctor. “Baseband Processing in Analog Combining MIMO Systems: From Theoretical Design to FPGA Implementation: Procesado Banda Base en sistemas MIMO basados en combinación analógica de antenas : del diseño teórico a la implementación FPGA : tesis doctoral.” 2011. Web. 04 Mar 2021.
Vancouver:
Elvira Arregui V. Baseband Processing in Analog Combining MIMO Systems: From Theoretical Design to FPGA Implementation: Procesado Banda Base en sistemas MIMO basados en combinación analógica de antenas : del diseño teórico a la implementación FPGA : tesis doctoral. [Internet] [Doctoral dissertation]. Universidad de Cantabria; 2011. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/10902/1343.
Council of Science Editors:
Elvira Arregui V. Baseband Processing in Analog Combining MIMO Systems: From Theoretical Design to FPGA Implementation: Procesado Banda Base en sistemas MIMO basados en combinación analógica de antenas : del diseño teórico a la implementación FPGA : tesis doctoral. [Doctoral Dissertation]. Universidad de Cantabria; 2011. Available from: http://hdl.handle.net/10902/1343
Queens University
2.
Abou Saleh, Hassan.
Predictive Wireless Antenna Selection for High Mobility Conditions
.
Degree: Electrical and Computer Engineering, 2013, Queens University
URL: http://hdl.handle.net/1974/7791
► Accurate channel knowledge is indispensable to the practical success of channel-aware wireless communication technologies. However, channel estimates obtained from pilot symbols rapidly become outdated due…
(more)
▼ Accurate channel knowledge is indispensable to the practical success of channel-aware wireless communication technologies. However, channel estimates obtained from pilot symbols rapidly become outdated due to fast time variations of multipath fading channels.
To reduce system cost, antenna subset selection reduces radio frequency (RF) chain components. For systems selecting a subset of a plurality of antennas for reception, this outdated channel information is a significant impediment to selection and data decoding reliability.
In this thesis, training-based schemes for antenna selection (AS) for time-varying channels which account for practical constraints such as training, packetization and antenna switching time are proposed based on discrete prolate spheroidal sequences. They only operate with knowledge or estimates of the Doppler frequency and the channel signal-to-noise ratio (SNR), but do not require detailed statistical correlation knowledge.
A pilot-based AS scheme for time-varying frequency-flat channels for single input-multiple output (SIMO) systems selecting one of a plurality of antennas using packet or symbol-rate antenna switching is first proposed. It is demonstrated that the presented scheme provides significant performance gain over AS methods using Fourier-based orthogonal training as well as over single antenna systems with perfect channel knowledge. Analytical expressions for the symbol error probability (SEP) of M-ary phase-shift keying (MPSK) for systems employing the suggested techniques are provided.
The second part of this thesis investigates the more general case of selecting a subset of a plurality of receive antennas. A new pilot-based receive antenna subset selection algorithm for time-varying frequency-flat channels is presented. The proposed AS algorithm is shown to outperform AS methods based on Fourier prediction/estimation as well as SIMO systems with perfect channel knowledge. Analysis of MPSK and quadrature amplitude modulation (MQAM) SEP for systems with receive AS is provided.
The combination of AS and orthogonal frequency division multiplexing (OFDM) over the more realistic time-varying and frequency-selective fading scenario is examined in the final part. Training schemes for receive AS using packet-rate antenna switching for SIMO and multiple input-multiple output (MIMO) OFDM systems are developed. The suggested schemes exhibit a superior performance over AS methods using either linear interpolation/extrapolation or Fourier prediction/estimation techniques.
Subjects/Keywords: Wireless Communications
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APA (6th Edition):
Abou Saleh, H. (2013). Predictive Wireless Antenna Selection for High Mobility Conditions
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/7791
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):
Abou Saleh, Hassan. “Predictive Wireless Antenna Selection for High Mobility Conditions
.” 2013. Thesis, Queens University. Accessed March 04, 2021.
http://hdl.handle.net/1974/7791.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Abou Saleh, Hassan. “Predictive Wireless Antenna Selection for High Mobility Conditions
.” 2013. Web. 04 Mar 2021.
Vancouver:
Abou Saleh H. Predictive Wireless Antenna Selection for High Mobility Conditions
. [Internet] [Thesis]. Queens University; 2013. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/1974/7791.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Abou Saleh H. Predictive Wireless Antenna Selection for High Mobility Conditions
. [Thesis]. Queens University; 2013. Available from: http://hdl.handle.net/1974/7791
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Virginia Tech
3.
La Pan, Matthew Jonathan.
Security Issues for Modern Communications Systems: Fundamental Electronic Warfare Tactics for 4G Systems and Beyond.
Degree: PhD, Electrical Engineering, 2014, Virginia Tech
URL: http://hdl.handle.net/10919/51042
► In the modern era of wireless communications, radios are becoming increasingly more cognitive. As the complexity and robustness of friendly communications increases, so do the…
(more)
▼ In the modern era of
wireless communications, radios are becoming increasingly more cognitive. As the complexity and robustness of friendly
communications increases, so do the abilities of adversarial jammers. The potential uses and threats of these jammers directly pertain to fourth generation (4G) communication standards, as well as future standards employing similar physical layer technologies.
This paper investigates a number of threats to the technologies utilized by 4G and future systems, as well as potential improvements to the security and robustness of these
communications systems. The work undertaken highlights potential attacks at both the physical layer and the multiple access control (MAC) layer along with improvements to the technologies which they target.
This work presents a series of intelligent, targeted jamming attacks against the orthogonal frequency division multiplexing (OFDM) synchronization process to demonstrate some security flaws in existing 4G technology, as well as to highlight some of the potential tools of a cognitive electronic warfare attack device. Performance analysis of the OFDM synchronization process are demonstrated in the presence of the efficient attacks, where in many cases complete denial of service is induced.
A method for cross ambiguity function (CAF) based OFDM synchronization is presented as a security and mitigation tactic for 4G devices in the context of cognitive warfare scenarios. The method is shown to maintain comparable performance to other correlation based synchronization estimators while offering the benefit of a disguised preamble. Sync-amble randomization is also discussed as a combinatory strategy with CAF based OFDM synchronization to prevent cognitive jammers for tracking and targeting OFDM synchronization.
Finally, this work presents a method for dynamic spectrum access (DSA) enabled radio identification based solely on radio frequency (RF) observation. This method represents the framework for which both the cognitive jammer and anti-jam radio would perform cognitive sensing in order to utilize the intelligent physical layer attack and mitigation strategies previously discussed. The identification algorithm is shown to be theoretically effective in classifying and identifying two DSA radios with distinct operating policies.
Advisors/Committee Members: Clancy, Thomas Charles (committeechair), McGwier, Robert W. (committeechair), Reed, Jeffrey H. (committee member), Hancock, Kathleen L. (committee member), Shukla, Sandeep K. (committee member).
Subjects/Keywords: Wireless Communications
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APA (6th Edition):
La Pan, M. J. (2014). Security Issues for Modern Communications Systems: Fundamental Electronic Warfare Tactics for 4G Systems and Beyond. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/51042
Chicago Manual of Style (16th Edition):
La Pan, Matthew Jonathan. “Security Issues for Modern Communications Systems: Fundamental Electronic Warfare Tactics for 4G Systems and Beyond.” 2014. Doctoral Dissertation, Virginia Tech. Accessed March 04, 2021.
http://hdl.handle.net/10919/51042.
MLA Handbook (7th Edition):
La Pan, Matthew Jonathan. “Security Issues for Modern Communications Systems: Fundamental Electronic Warfare Tactics for 4G Systems and Beyond.” 2014. Web. 04 Mar 2021.
Vancouver:
La Pan MJ. Security Issues for Modern Communications Systems: Fundamental Electronic Warfare Tactics for 4G Systems and Beyond. [Internet] [Doctoral dissertation]. Virginia Tech; 2014. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/10919/51042.
Council of Science Editors:
La Pan MJ. Security Issues for Modern Communications Systems: Fundamental Electronic Warfare Tactics for 4G Systems and Beyond. [Doctoral Dissertation]. Virginia Tech; 2014. Available from: http://hdl.handle.net/10919/51042
Oregon State University
4.
Yildirim, Ferhat (Ahmet Ferhat).
Directional 60 GHz communication networks.
Degree: PhD, Electical and Computer Engineering, 2009, Oregon State University
URL: http://hdl.handle.net/1957/12844
► It is well known that multipath effects cause inter-symbol interference (ISI) for high-speed signaling and ultimately limit the achievable data rate at any frequency band.…
(more)
▼ It is well known that multipath effects cause inter-symbol interference (ISI) for high-speed signaling and ultimately limit the achievable data rate at any frequency band. In this thesis, we study several different methods to tackle this issue and provide solutions for establishing efficient
wireless links that can provide several Gbps data rate. Specifically, we show that proper choice of polarization, when used with the proposed topology detection algorithm reduces the multipath in 60 GHz
wireless channel and increases the error-performance of the network. We also develop a direction-detection algorithm for directional
communications in 60 GHz, which is proven to be effective in reducing multipath and increasing spatial diversity. Finally, we propose a double directional channel model for 60 GHz channel as a modification to IEEE 802.15.3c channel model to include the effects of directional antennas both on the transmitter and the receiver side.
Advisors/Committee Members: Liu, Huaping (advisor), Magana, Mario (committee member).
Subjects/Keywords: Wireless communications; Wireless communication systems – Mathematical models
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APA (6th Edition):
Yildirim, F. (. F. (2009). Directional 60 GHz communication networks. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/12844
Chicago Manual of Style (16th Edition):
Yildirim, Ferhat (Ahmet Ferhat). “Directional 60 GHz communication networks.” 2009. Doctoral Dissertation, Oregon State University. Accessed March 04, 2021.
http://hdl.handle.net/1957/12844.
MLA Handbook (7th Edition):
Yildirim, Ferhat (Ahmet Ferhat). “Directional 60 GHz communication networks.” 2009. Web. 04 Mar 2021.
Vancouver:
Yildirim F(F. Directional 60 GHz communication networks. [Internet] [Doctoral dissertation]. Oregon State University; 2009. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/1957/12844.
Council of Science Editors:
Yildirim F(F. Directional 60 GHz communication networks. [Doctoral Dissertation]. Oregon State University; 2009. Available from: http://hdl.handle.net/1957/12844
Queensland University of Technology
5.
Das Gupta, Jishu.
Effect of pedestrian movement on MIMO-OFDM channel capacity in an indoor environment.
Degree: 2010, Queensland University of Technology
URL: https://eprints.qut.edu.au/38632/
► The rapid growth of mobile telephone use, satellite services, and now the wireless Internet and WLANs are generating tremendous changes in telecommunication and networking. As…
(more)
▼ The rapid growth of mobile telephone use, satellite services, and now the wireless Internet and WLANs are generating tremendous changes in telecommunication and networking. As indoor wireless communications become more prevalent, modeling indoor radio wave propagation in populated environments is a topic of significant interest. Wireless MIMO communication exploits phenomena such as multipath propagation to increase data throughput and range, or reduce bit error rates, rather than attempting to eliminate effects of multipath propagation as traditional SISO communication systems seek to do. The MIMO approach can yield significant gains for both link and network capacities, with no additional transmitting power or bandwidth consumption when compared to conventional single-array diversity methods. When MIMO and OFDM systems are combined and deployed in a suitable rich scattering environment such as indoors, a significant capacity gain can be observed due to the assurance of multipath propagation. Channel variations can occur as a result of movement of personnel, industrial machinery, vehicles and other equipment moving within the indoor environment. The time-varying effects on the propagation channel in populated indoor environments depend on the different pedestrian traffic conditions and the particular type of environment considered. A systematic measurement campaign to study pedestrian movement effects in indoor MIMO-OFDM channels has not yet been fully undertaken. Measuring channel variations caused by the relative positioning of pedestrians is essential in the study of indoor MIMO-OFDM broadband wireless networks. Theoretically, due to high multipath scattering, an increase in MIMO-OFDM channel capacity is expected when pedestrians are present. However, measurements indicate that some reductions in channel capacity could be observed as the number of pedestrians approaches 10 due to a reduction in multipath conditions as more human bodies absorb the wireless signals. This dissertation presents a systematic characterization of the effects of pedestrians in indoor MIMO-OFDM channels. Measurement results, using the MIMO-OFDM channel sounder developed at the CSIRO ICT Centre, have been validated by a customized Geometric Optics-based ray tracing simulation. Based on measured and simulated MIMO-OFDM channel capacity and MIMO-OFDM capacity dynamic range, an improved deterministic model for MIMO-OFDM channels in indoor populated environments is presented. The model can be used for the design and analysis of future WLAN to be deployed in indoor environments. The results obtained show that, in both Fixed SNR and Fixed Tx for deterministic condition, the channel capacity dynamic range rose with the number of pedestrians as well as with the number of antenna combinations. In random scenarios with 10 pedestrians, an increment in channel capacity of up to 0.89 bits/sec/Hz in Fixed SNR and up to 1.52 bits/sec/Hz in Fixed Tx has been recorded compared to the one pedestrian scenario. In addition, from the results a maximum increase…
Subjects/Keywords: MIMO-OFDM; wireless communications; indoor wireless transmissions
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APA (6th Edition):
Das Gupta, J. (2010). Effect of pedestrian movement on MIMO-OFDM channel capacity in an indoor environment. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/38632/
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):
Das Gupta, Jishu. “Effect of pedestrian movement on MIMO-OFDM channel capacity in an indoor environment.” 2010. Thesis, Queensland University of Technology. Accessed March 04, 2021.
https://eprints.qut.edu.au/38632/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Das Gupta, Jishu. “Effect of pedestrian movement on MIMO-OFDM channel capacity in an indoor environment.” 2010. Web. 04 Mar 2021.
Vancouver:
Das Gupta J. Effect of pedestrian movement on MIMO-OFDM channel capacity in an indoor environment. [Internet] [Thesis]. Queensland University of Technology; 2010. [cited 2021 Mar 04].
Available from: https://eprints.qut.edu.au/38632/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Das Gupta J. Effect of pedestrian movement on MIMO-OFDM channel capacity in an indoor environment. [Thesis]. Queensland University of Technology; 2010. Available from: https://eprints.qut.edu.au/38632/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Arizona
6.
Akgun, Berk.
Achieving Secure Communications in Dense Multiuser Mimo Systems for 5G and Beyond
.
Degree: 2019, University of Arizona
URL: http://hdl.handle.net/10150/636623
► Traditional approaches for providing confidentiality of wirelessly transmitted signals are often based on cryptographic techniques. While these techniques ensure that messages are encrypted and secured…
(more)
▼ Traditional approaches for providing confidentiality of wirelessly transmitted signals are often based on cryptographic techniques. While these techniques ensure that messages are encrypted and secured against eavesdropping, they are not sufficient to protect important transmission attributes at the physical (PHY) layer. Specifically, several elds in the headers of PHY and medium access control (MAC) frames are typically sent unencrypted to maintain proper protocol functionality (e.g., sender/receiver identification). As a result, they leak side-channel information (SCI), including payload size, frequency and phase oset, modulation and coding scheme, identities of communication nodes, frame type, transmission rate, etc. These SCI can be exploited by an adversary to launch various passive (eavesdropping) and active (jamming) attacks. To complement cryptographic techniques used at upper layers and prevent the leakage of SCI at the PHY/MAC layers, PHY-layer security techniques have been introduced. These techniques exploit the characteristics of the
wireless channel along with multiple-input multiple-output (MIMO) technologies, in which multiple transmitting and receiving antennas are utilized to prevent information leakage to eavesdroppers and/or avoid jamming attacks. In particular, if the signal-to-interference-plus-noise ratio (SINR) at an adversary is lower than the one at a legitimate receiver, secure communication can be achieved through the so-called wiretap coding. MIMO systems enable the transmitter and/or the receiver to generate artificial noise, called friendly jamming (FJ), so as to reduce the SINR at the adversary without impacting the SINR at the legitimate receiver. In this dissertation, we focus on exploring the security threats to next-generation
wireless systems. We develop MIMO-based PHY-layer security methods to achieve reliable and secret
communications in these systems. First, we consider a broadcast channel, in which a multi-antenna transmitter (Alice) sends K confidential information signals to K legitimate receivers (Bobs) in the presence of L eavesdropping devices (Eves). Alice uses MIMO precoding to generate the information signals along with her own Tx-based friendly jamming (TxFJ). Interference at each Bob is removed via a technique called MIMO zero-forcing. This TxFJ, however, leaves an eavesdropping \vulnerability region" in the proximity of each Bob, which can be exploited by a nearby Eve. Specically, because of the high correlation in the channel state information (CSI) at a Bob and nearby Eves, the TxFJ becomes less effective in preventing eavesdropping at these Eves. We address this problem by augmenting TxFJ with receiver-based friendly jamming (RxFJ), generated by each Bob. Specifically, we allow each Bob to use self-interference suppression (SIS) techniques to transmit a friendly jamming signal while simultaneously receiving an information signal over the same channel. These SIS techniques exploit circulators to attenuate the self-interference power of RxFJ at Bobs and utilize…
Advisors/Committee Members: Krunz, Marwan (advisor), Djordjevic, Ivan (committeemember), Lazos, Loukas (committeemember).
Subjects/Keywords: Computer Networking;
Wireless Communications;
Wireless Security
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APA (6th Edition):
Akgun, B. (2019). Achieving Secure Communications in Dense Multiuser Mimo Systems for 5G and Beyond
. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/636623
Chicago Manual of Style (16th Edition):
Akgun, Berk. “Achieving Secure Communications in Dense Multiuser Mimo Systems for 5G and Beyond
.” 2019. Doctoral Dissertation, University of Arizona. Accessed March 04, 2021.
http://hdl.handle.net/10150/636623.
MLA Handbook (7th Edition):
Akgun, Berk. “Achieving Secure Communications in Dense Multiuser Mimo Systems for 5G and Beyond
.” 2019. Web. 04 Mar 2021.
Vancouver:
Akgun B. Achieving Secure Communications in Dense Multiuser Mimo Systems for 5G and Beyond
. [Internet] [Doctoral dissertation]. University of Arizona; 2019. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/10150/636623.
Council of Science Editors:
Akgun B. Achieving Secure Communications in Dense Multiuser Mimo Systems for 5G and Beyond
. [Doctoral Dissertation]. University of Arizona; 2019. Available from: http://hdl.handle.net/10150/636623
University of New South Wales
7.
Naghshin, Vahid.
Modeling and Analysis of Wireless Communications Networks: Multi-tier Cellular and Ad Hoc Networks.
Degree: Engineering & Information Technology, 2017, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/59019
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48292/SOURCE02?view=true
► Due to the proliferation of data-hungry applications in smartphones and other personal mobile devices, the demand for higher data rate is increasing. This phenomenon has…
(more)
▼ Due to the proliferation of data-hungry applications in smartphones and other personal mobile devices, the demand for higher data rate is increasing. This phenomenon has a huge impact on architecture of
wireless cellular networks. Based on this fact, the architecture of
wireless cellular networks is transforming from voice-centric and centrally-controlled to the data-centric and distributed, in order to address the massive data demand of users.One efficient approach to implement the data-centric and distributed
wireless cellular networks is
wireless heterogeneous cellular networks (HCN), where a multitude of radio access points with different technologies and platforms can interoperate flexibly and intelligently. However, augmenting the conventional
wireless cellular networks with access points of different characteristics will introduce new challenges in integrating different access points to reach seamless connectivity.In order to address the broad range of challenges we face in HCNs, the need for efficient and accurate model to capture the main features of
wireless networks is paramount. The proposed model should be general but not too complicated to be difficult to gain insight. Stochastic geometry has been proven to be a powerful mathematical tool in modeling
wireless networks with irregular topologies. In this work, we incorporate principles from stochastic geometry by modeling the
wireless networks via using point processes such as Poisson point process (PPP) and Binomial point process (BPP).To be more specific, we have exploited the PPP model in modeling
wireless HCNs, while BPP model is used to model
wireless ad hoc networks.In this thesis, we first analyze the performance of finite
wireless networks in the context of
wireless ad hoc networks and
wireless HCNs. The significance of this part is emphasized by this fact that, in most practical scenarios the number of
wireless nodes and access points is predefined and fixed and they are deployed in a finite region. The network performance is measured from different aspects such as interference distribution, outage probability, throughput, capacity, and cell association area. In all of these scenarios, we incorporate signal-to-interference-plus-noise ratio (SINR) metrics to measure the performance of different multiple access channel schemes and association protocols.In the second part of this thesis, we focus on
wireless HCNs using the PPP model where the number of nodes and size of the deployed region can be arbitrarily large. Most of previous works focus on the case that only downlink or uplink (not both) transmissions are possible at a given channel spectrum and instant of time. In this work, we derive the network performance for decoupled association and concurrent uplink and downlink transmissions. Furthermore, different traffic patterns are studied to highlight its contribution on network performance.Finally, in the last part of the thesis, we consider the cellular-based machine type communication, where a massive number of machine type devices are…
Advisors/Committee Members: Reed, Mark, Engineering & Information Technology, UNSW Canberra, UNSW, Aboutorab, Neda, Engineering & Information Technology, UNSW Canberra, UNSW, Pickering , Mark, Engineering & Information Technology, UNSW Canberra, UNSW.
Subjects/Keywords: Stochastic Geometry; Wireless communications; Wireless cellualr networks
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APA ·
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Manager
APA (6th Edition):
Naghshin, V. (2017). Modeling and Analysis of Wireless Communications Networks: Multi-tier Cellular and Ad Hoc Networks. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/59019 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48292/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Naghshin, Vahid. “Modeling and Analysis of Wireless Communications Networks: Multi-tier Cellular and Ad Hoc Networks.” 2017. Doctoral Dissertation, University of New South Wales. Accessed March 04, 2021.
http://handle.unsw.edu.au/1959.4/59019 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48292/SOURCE02?view=true.
MLA Handbook (7th Edition):
Naghshin, Vahid. “Modeling and Analysis of Wireless Communications Networks: Multi-tier Cellular and Ad Hoc Networks.” 2017. Web. 04 Mar 2021.
Vancouver:
Naghshin V. Modeling and Analysis of Wireless Communications Networks: Multi-tier Cellular and Ad Hoc Networks. [Internet] [Doctoral dissertation]. University of New South Wales; 2017. [cited 2021 Mar 04].
Available from: http://handle.unsw.edu.au/1959.4/59019 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48292/SOURCE02?view=true.
Council of Science Editors:
Naghshin V. Modeling and Analysis of Wireless Communications Networks: Multi-tier Cellular and Ad Hoc Networks. [Doctoral Dissertation]. University of New South Wales; 2017. Available from: http://handle.unsw.edu.au/1959.4/59019 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:48292/SOURCE02?view=true
University of Alberta
8.
Feng, Chi.
Interference Analysis of Massive MIMO Downlink with MRT
Precoding and Applications in Performance Analysis.
Degree: MS, Department of Electrical and Computer
Engineering, 2016, University of Alberta
URL: https://era.library.ualberta.ca/files/c3x816m822
► Recently, massive MIMO (multiple-input-multiple-output) systems, where the base station (BS) is equipped with hundreds of small, low-cost, and low-power antennas, have been proposed as one…
(more)
▼ Recently, massive MIMO
(multiple-input-multiple-output) systems, where the base station
(BS) is equipped with hundreds of small, low-cost, and low-power
antennas, have been proposed as one of the promising technologies
for the next generation cellular systems. The thesis works on the
performance analysis of single-cell multi-user massive MIMO
downlink. Perfect channel state information (CSI) is assumed at the
BS and maximum ratio transmission (MRT) precoding scheme is
adopted. We first investigate the distribution of the interference
power and derive its probability density function (pdf) by central
limit theory. After that, analytical results on the outage
probability and the sum-rate are derived. Different to existing
work using the law of large numbers to derive the asymptotic
deterministic signal-to-interference-plus-noise-ratio (SINR), the
randomness of the interference in the SINR is kept intact in our
work, which allows the derivation of the outage probability. We
further extend to networks with per-antenna power constraint. A
modified MRT precoding scheme is proposed and the performance of
the modified scheme is analyzed. Our work show that the modified
MRT precoding can achieve lower outage probability and higher
sum-rate than MRT precoding, even with more strict power
constraint.
Subjects/Keywords: Massive MIMO; Wireless communications
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APA (6th Edition):
Feng, C. (2016). Interference Analysis of Massive MIMO Downlink with MRT
Precoding and Applications in Performance Analysis. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/c3x816m822
Chicago Manual of Style (16th Edition):
Feng, Chi. “Interference Analysis of Massive MIMO Downlink with MRT
Precoding and Applications in Performance Analysis.” 2016. Masters Thesis, University of Alberta. Accessed March 04, 2021.
https://era.library.ualberta.ca/files/c3x816m822.
MLA Handbook (7th Edition):
Feng, Chi. “Interference Analysis of Massive MIMO Downlink with MRT
Precoding and Applications in Performance Analysis.” 2016. Web. 04 Mar 2021.
Vancouver:
Feng C. Interference Analysis of Massive MIMO Downlink with MRT
Precoding and Applications in Performance Analysis. [Internet] [Masters thesis]. University of Alberta; 2016. [cited 2021 Mar 04].
Available from: https://era.library.ualberta.ca/files/c3x816m822.
Council of Science Editors:
Feng C. Interference Analysis of Massive MIMO Downlink with MRT
Precoding and Applications in Performance Analysis. [Masters Thesis]. University of Alberta; 2016. Available from: https://era.library.ualberta.ca/files/c3x816m822
UCLA
9.
Chen, Jesse.
MIMO Enhancements for Air-to-Ground Wireless Communications.
Degree: Electrical Engineering, 2014, UCLA
URL: http://www.escholarship.org/uc/item/7jk730rg
► In order to introduce the benefits of Multiple-Input/Multiple-Output (MIMO) wireless solutions into the airborne environment for maximal effect, the airborne channel must be fully understood.…
(more)
▼ In order to introduce the benefits of Multiple-Input/Multiple-Output (MIMO) wireless solutions into the airborne environment for maximal effect, the airborne channel must be fully understood. While there have been theoretical models proposed for the airborne channel, there has been very little work toward providing a practical channel model which has been validated by actual an airborne platform. This work presents a characterization of practical performance gains of a MIMO system over a conventional SISO, in a mobile air-to-ground environment. Field measurements were collected with an airborne 4x4 MIMO-OFDM channel-sounding platform at altitudes, speeds and flight patterns approximating medium-endurance vehicles flying over various terrain. Ground stations placed in multiple locations (different scattering scenarios) measured channel responses in addition to actual throughput statistics. Our studies indicate that significant throughput and range gains are achievable with MIMO. We also show that depending on application requirements, these MIMO-enabled gains can be converted into considerable power savings. We also present a study of the effects of introducing MIMO-enabled signaling techniques (such as eigen beamforming and spatial multiplexing) on the total link-capacity of a system of uncoordinated, air-to-ground link-pairs deployed to a single area of operations. Captured channel measurements from the earlier real-world airborne study were inserted into our multi-link simulation environment. Trials were run under several representative aerial-deployment scenarios, revealing significant gains in link capacity. Finally, we consider the potential throughput enhancement delivered by full-duplex signaling and its limitations due to desensitization of receiver hardware by self-generated interference (SI). Existing SI cancellation solutions are prohibitive for long-range/airborne applications due to power handling limitations. They are also not easily scalable for an arbitrary number of MIMO antennas in arbitrary positions. A host-agnostic, high-power, adaptive SI canceler design is proposed and a hardware prototype is presented. Performance enhancement with an off-the-shelf host radio was demonstrated in the presence of varying SI signal profiles.
Subjects/Keywords: Electrical engineering; Communications; MIMO; Wireless
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APA (6th Edition):
Chen, J. (2014). MIMO Enhancements for Air-to-Ground Wireless Communications. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/7jk730rg
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):
Chen, Jesse. “MIMO Enhancements for Air-to-Ground Wireless Communications.” 2014. Thesis, UCLA. Accessed March 04, 2021.
http://www.escholarship.org/uc/item/7jk730rg.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chen, Jesse. “MIMO Enhancements for Air-to-Ground Wireless Communications.” 2014. Web. 04 Mar 2021.
Vancouver:
Chen J. MIMO Enhancements for Air-to-Ground Wireless Communications. [Internet] [Thesis]. UCLA; 2014. [cited 2021 Mar 04].
Available from: http://www.escholarship.org/uc/item/7jk730rg.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chen J. MIMO Enhancements for Air-to-Ground Wireless Communications. [Thesis]. UCLA; 2014. Available from: http://www.escholarship.org/uc/item/7jk730rg
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
10.
Silva, Mário Marques da.
Multi-User Detection for DS-CDMA Systems.
Degree: 1999, Instituto Superior Técnico
URL: http://www.rcaap.pt/detail.jsp?id=oai:repositorio.ual.pt:11144/349
► The main purpose in wireless communications is to allow high data rates, low delays, high net capacity and flexibility in services. The Direct Spreading –…
(more)
▼ The main purpose in wireless communications is to allow high data rates, low delays, high net capacity and flexibility in services. The Direct Spreading – Code Division Multiple Access (DS-CDMA) technology is the main key to combat several sources of interference.
The Intersymbol Interference (ISI) tends to increase with the increase in the symbol rates. To combat the ISI, this thesis improve the ISI Cancellation System, named “Commutation Signaling”. Additionally, presents the use of DS-CDMA technology, and because all the spectrum is available to all users at the same time, there is Multiple Access Interference (MAI), which is caused because several spreading codes used by several users are not received by one reference user perfectly orthogonal.
This thesis studies Subtractive Multi-User Detectors (SIC – Successive Interference Cancellation, and PIC – Parallel Interference Cancellation) without and with the ISI Cancellation System – Commutation Signaling. Additionally, studies the detection with Noise Whitening Matched Filter (NWMF) that combats the MAI with the whitening of the interference power spectrum, and so, following the Single-User strategy, also without and with the ISI Cancellation System – Commutation Signaling.
Subjects/Keywords: wireless communications
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Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Silva, M. M. d. (1999). Multi-User Detection for DS-CDMA Systems. (Thesis). Instituto Superior Técnico. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:repositorio.ual.pt:11144/349
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):
Silva, Mário Marques da. “Multi-User Detection for DS-CDMA Systems.” 1999. Thesis, Instituto Superior Técnico. Accessed March 04, 2021.
http://www.rcaap.pt/detail.jsp?id=oai:repositorio.ual.pt:11144/349.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Silva, Mário Marques da. “Multi-User Detection for DS-CDMA Systems.” 1999. Web. 04 Mar 2021.
Vancouver:
Silva MMd. Multi-User Detection for DS-CDMA Systems. [Internet] [Thesis]. Instituto Superior Técnico; 1999. [cited 2021 Mar 04].
Available from: http://www.rcaap.pt/detail.jsp?id=oai:repositorio.ual.pt:11144/349.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Silva MMd. Multi-User Detection for DS-CDMA Systems. [Thesis]. Instituto Superior Técnico; 1999. Available from: http://www.rcaap.pt/detail.jsp?id=oai:repositorio.ual.pt:11144/349
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
North Carolina State University
11.
Domizioli, Carlo Peter.
Noise Analysis and Low-Noise Design for Compact Multi-Antenna Receivers: A Communication Theory Perspective.
Degree: PhD, Electrical Engineering, 2009, North Carolina State University
URL: http://www.lib.ncsu.edu/resolver/1840.16/4553
► Multiple-input, multiple-output (MIMO) wireless communication systems combine the deployment of multiple antennas at both the transmitter and receiver with sophisticated signal processing to improve the…
(more)
▼ Multiple-input, multiple-output (MIMO)
wireless communication systems combine the deployment of multiple antennas at both the transmitter and receiver with sophisticated signal processing to improve the performance of
wireless communications. As with any communication system, developing an accurate yet mathematically tractable channel model is essential to analyzing the performance of actual systems. Prior studies of MIMO channel modeling have provided detailed models for fading correlation – either due to the
propagation environment or through mutual coupling between the antennas – and how this correlation affects performance. On the other hand, relatively little attention has been paid to the noise correlation.
In this dissertation we consider noise analysis and low-noise design for compact MIMO receivers. We begin by analyzing the performance of several MIMO communication schemes in the presence of fading and noise correlation. It is shown that fading and noise correlation have opposite effects on performance, so properly accounting for
both in the channel model is crucial to accurately predicting performance. Next we develop a circuit model for compact multi-antenna receivers that includes noise generated by the antennas, front-end amplifiers, and other components. Through analytical and numerical examples we demonstrate that the noise may
be correlated, and that different noise sources may impact performance in profoundly different ways. Finally, we derive low-noise design theorems for MIMO front-ends from communication-theoretic principles.
Advisors/Committee Members: Brian L. Hughes, Committee Chair (advisor), Kevin G. Gard, Committee Member (advisor), Gianluca Lazzi, Committee Member (advisor), J. Keith Townsend, Committee Member (advisor), Stephen L. Campbell, Committee Member (advisor).
Subjects/Keywords: MIMO; mutual coupling; wireless communications
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Export
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APA (6th Edition):
Domizioli, C. P. (2009). Noise Analysis and Low-Noise Design for Compact Multi-Antenna Receivers: A Communication Theory Perspective. (Doctoral Dissertation). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/4553
Chicago Manual of Style (16th Edition):
Domizioli, Carlo Peter. “Noise Analysis and Low-Noise Design for Compact Multi-Antenna Receivers: A Communication Theory Perspective.” 2009. Doctoral Dissertation, North Carolina State University. Accessed March 04, 2021.
http://www.lib.ncsu.edu/resolver/1840.16/4553.
MLA Handbook (7th Edition):
Domizioli, Carlo Peter. “Noise Analysis and Low-Noise Design for Compact Multi-Antenna Receivers: A Communication Theory Perspective.” 2009. Web. 04 Mar 2021.
Vancouver:
Domizioli CP. Noise Analysis and Low-Noise Design for Compact Multi-Antenna Receivers: A Communication Theory Perspective. [Internet] [Doctoral dissertation]. North Carolina State University; 2009. [cited 2021 Mar 04].
Available from: http://www.lib.ncsu.edu/resolver/1840.16/4553.
Council of Science Editors:
Domizioli CP. Noise Analysis and Low-Noise Design for Compact Multi-Antenna Receivers: A Communication Theory Perspective. [Doctoral Dissertation]. North Carolina State University; 2009. Available from: http://www.lib.ncsu.edu/resolver/1840.16/4553
12.
Silva, Mário Marques da.
Multi-User Detection for DS-CDMA Systems.
Degree: 1999, Instituto Superior Técnico
URL: http://www.rcaap.pt/detail.jsp?id=oai:localhost:11144/349
► The main purpose in wireless communications is to allow high data rates, low delays, high net capacity and flexibility in services. The Direct Spreading –…
(more)
▼ The main purpose in wireless communications is to allow high data rates, low delays, high net capacity and flexibility in services. The Direct Spreading – Code Division Multiple Access (DS-CDMA) technology is the main key to combat several sources of interference.
The Intersymbol Interference (ISI) tends to increase with the increase in the symbol rates. To combat the ISI, this thesis improve the ISI Cancellation System, named “Commutation Signaling”. Additionally, presents the use of DS-CDMA technology, and because all the spectrum is available to all users at the same time, there is Multiple Access Interference (MAI), which is caused because several spreading codes used by several users are not received by one reference user perfectly orthogonal.
This thesis studies Subtractive Multi-User Detectors (SIC – Successive Interference Cancellation, and PIC – Parallel Interference Cancellation) without and with the ISI Cancellation System – Commutation Signaling. Additionally, studies the detection with Noise Whitening Matched Filter (NWMF) that combats the MAI with the whitening of the interference power spectrum, and so, following the Single-User strategy, also without and with the ISI Cancellation System – Commutation Signaling.
Subjects/Keywords: wireless communications
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Silva, M. M. d. (1999). Multi-User Detection for DS-CDMA Systems. (Thesis). Instituto Superior Técnico. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:localhost:11144/349
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):
Silva, Mário Marques da. “Multi-User Detection for DS-CDMA Systems.” 1999. Thesis, Instituto Superior Técnico. Accessed March 04, 2021.
http://www.rcaap.pt/detail.jsp?id=oai:localhost:11144/349.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Silva, Mário Marques da. “Multi-User Detection for DS-CDMA Systems.” 1999. Web. 04 Mar 2021.
Vancouver:
Silva MMd. Multi-User Detection for DS-CDMA Systems. [Internet] [Thesis]. Instituto Superior Técnico; 1999. [cited 2021 Mar 04].
Available from: http://www.rcaap.pt/detail.jsp?id=oai:localhost:11144/349.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Silva MMd. Multi-User Detection for DS-CDMA Systems. [Thesis]. Instituto Superior Técnico; 1999. Available from: http://www.rcaap.pt/detail.jsp?id=oai:localhost:11144/349
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Urbana-Champaign
13.
Wilcox, Timothy A.
Performance of wireless off-road vehicular networks.
Degree: MS, 0102, 2011, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/18529
► Advances in wireless technology and an increasing demand for new applications that require in-field communication are generating more interest in off-road vehicular networks than ever…
(more)
▼ Advances in
wireless technology and an increasing demand for new applications that require in-field communication are generating more interest in off-road vehicular networks than ever before. Current on-road and off-road vehicular networking technologies are either cost prohibitive, bandwidth limited, or exhibit too much latency. 802.11 standard networks are a low-cost, readily available technology that have the potential of integrating effectively with current off road equipment software and hardware.
The main objective of this research was to develop a baseline for the performance of an 802.11b/g
wireless network in a realistic in-field agricultural environment. While recognizing there are many external factors that can degrade the performance and reliability of such a system, this research was focused on identifying and measuring the performance effects of varying parameters that can be controlled, in particular the data rate, packet size, and the choice of 802.11b versus 802.11g protocols.
The performance of the system was measured by recording packets at both the transmitting and receiving devices and calculating the percentage of packets received at varying distances between the nodes. A simple two node network between two tractors was constructed for performance testing, and an application was written that used personal computers on each tractor to generate and log network traffic simultaneously. A series of 18 tests were executed with varying data rates, protocols, and packet sizes in realistic in-field conditions. Data were then post-processed so that they could be easily analyzed with the aid of Microsoft ExcelTM.
The 802.11b network performed much better in the outdoor environment by transmitting data more reliably and farther than the 802.11g network. 802.11g networks exhibited a high reliability region, usually at small distances between nodes, and a region with less reliability, at larger distances between nodes. Increasing 802.11g data rates decreased the distance over which the network would reliably transmit, but increasing 802.11b data rates had little effect on maximum transmission distance, although they decreased the overall reliability of the network. For packets between 15 and 1400 bytes in length, small but statistically significant decreases in reliability were observed with increasing packet size. For the largest packet size of 2200 bytes, more notable reliability decreases were observed. The network performance was influenced by the angle of the transmitted wave relative to the tractor orientation. Finally, performance degradation due to signal reflections off the soil surface could be observed at distinct distances between nodes.
Advisors/Committee Members: Hansen, Alan C. (advisor).
Subjects/Keywords: 802.11; Vehicular Communication; Wireless Communications
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APA (6th Edition):
Wilcox, T. A. (2011). Performance of wireless off-road vehicular networks. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/18529
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):
Wilcox, Timothy A. “Performance of wireless off-road vehicular networks.” 2011. Thesis, University of Illinois – Urbana-Champaign. Accessed March 04, 2021.
http://hdl.handle.net/2142/18529.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wilcox, Timothy A. “Performance of wireless off-road vehicular networks.” 2011. Web. 04 Mar 2021.
Vancouver:
Wilcox TA. Performance of wireless off-road vehicular networks. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2011. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/2142/18529.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wilcox TA. Performance of wireless off-road vehicular networks. [Thesis]. University of Illinois – Urbana-Champaign; 2011. Available from: http://hdl.handle.net/2142/18529
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Melbourne
14.
SAMARASINGHE, THARAKA.
Opportunistic beamforming in wireless networks: optimal selective feedback policies and the feedback-capacity tradeoff.
Degree: 2012, University of Melbourne
URL: http://hdl.handle.net/11343/37736
► Opportunistic beamforming is a reduced feedback communication strategy for vector broadcast channels which only requires partial channel state information (CSI) at the base station for…
(more)
▼ Opportunistic beamforming is a reduced feedback communication strategy for vector broadcast channels which only requires partial channel state information (CSI) at the base station for its operation. Although reducing feedback, this strategy, in its plain implementations, displays a linear growth in the feedback load with the total number of users in the system, which can be an onerous requirement for large systems. This impracticality motivates the use of selective feedback techniques in which only the users with good channels are allowed to feedback. In this thesis, we focus on a more stringent but practical finite limit on the feedback load, and we study the structure of the sum-rate maximizing decentralized selective feedback policies, and how the resulting sum-rate compare to the sum-rate without any user selection.
Firstly, we set up the problem of finding the structure of downlink sum-rate maximizing selective decentralized feedback policies for opportunistic beamforming under finite feedback constraints on the average number of mobile users feeding back. We show that any sum-rate maximizing selective decentralized feedback policy must be a threshold feedback policy. This result holds for most practical fading channel models.
Then, the resulting optimum threshold selection problem is analyzed in detail. This is a non-convex optimization problem over finite dimensional Euclidean spaces. By utilizing the theory of majorization, an underlying Schur-concave structure in the sum-rate function is identified, and the sufficient conditions for the optimality of homogenous threshold feedback policies are obtained. Applications of these results are illustrated for well known fading channel models such as Rayleigh, Nakagami and Rician fading channels, along with various engineering and design insights. Rather surprisingly, it is shown that using the same threshold value at all mobile users is not always a rate-wise optimal feedback strategy, even for a network with statistically identical mobile users. For the Rayleigh fading channel model, on the other hand, homogenous threshold feedback policies are proven to be rate-wise optimal if multiple orthonormal data carrying beams are used to communicate with multiple mobile users simultaneously.
Having established the optimality of a homogenous threshold for a multi-beam Rayleigh fading environment, we then analyze the derivation of these optimum policies which ensure a O (1) feedback constraint as the number of users grows large. Starting with a set of statistically identical users, we obtain the tradeoff curve tracing the Pareto optimal boundary between feasible and infeasible feedback-capacity pairs for opportunistic beamforming. Any point on this tradeoff curve can be obtained by means of the derived threshold feedback policies, which are rate-wise optimal. We further show to what extent the O (1) feedback constraint must be relaxed to…
Subjects/Keywords: wireless communications; information theory
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APA ·
Chicago ·
MLA ·
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APA (6th Edition):
SAMARASINGHE, T. (2012). Opportunistic beamforming in wireless networks: optimal selective feedback policies and the feedback-capacity tradeoff. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/37736
Chicago Manual of Style (16th Edition):
SAMARASINGHE, THARAKA. “Opportunistic beamforming in wireless networks: optimal selective feedback policies and the feedback-capacity tradeoff.” 2012. Doctoral Dissertation, University of Melbourne. Accessed March 04, 2021.
http://hdl.handle.net/11343/37736.
MLA Handbook (7th Edition):
SAMARASINGHE, THARAKA. “Opportunistic beamforming in wireless networks: optimal selective feedback policies and the feedback-capacity tradeoff.” 2012. Web. 04 Mar 2021.
Vancouver:
SAMARASINGHE T. Opportunistic beamforming in wireless networks: optimal selective feedback policies and the feedback-capacity tradeoff. [Internet] [Doctoral dissertation]. University of Melbourne; 2012. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/11343/37736.
Council of Science Editors:
SAMARASINGHE T. Opportunistic beamforming in wireless networks: optimal selective feedback policies and the feedback-capacity tradeoff. [Doctoral Dissertation]. University of Melbourne; 2012. Available from: http://hdl.handle.net/11343/37736
Georgia Tech
15.
Han, Chong.
Physical layer solutions for ultra-broadband wireless communications in the terahertz band.
Degree: PhD, Electrical and Computer Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/54965
► In recent years, the wireless data traffic grew exponentially, which was further accompanied by an increasing demand for higher data rates. Towards this aim, Terahertz…
(more)
▼ In recent years, the
wireless data traffic grew exponentially, which was further accompanied by an increasing demand for higher data rates. Towards this aim, Terahertz band (0.1-10 THz) communication is envisioned as one of the key
wireless technologies of the next decade. The THz band will help to overcome the spectrum scarcity problems and capacity limitations of current
wireless networks, by providing an unprecedentedly large bandwidth. In addition, THz band communication will enable a plethora of long-awaited applications ranging from instantaneous massive data transfer among nearby devices in ultra-high-speed
wireless personal and local area networks, to ultra-high-definition content streaming over mobile devices in 5G and beyond small cells. The objective of the thesis is to establish the physical layer foundations of the ultra- broadband communication in the THz band. First, a unified multi-path propagation channel is modeled in the THz band, based on ray-tracing techniques. The wideband characterization are analyzed, which include the distance-varying spectral windows, the delay spread, the wideband capacity and the temporal broadening effects. Second, a multi-wideband waveform design for the THz band is proposed to improve the distance and support ultra- high-speed transmissions. Third, two algorithms for timing acquisition in the pulse-based
wireless systems are developed, namely the low-sampling-rate (LSR) algorithm, and the maximum likelihood (ML)-based approach. Fourth, the distance-aware bandwidth resource allocation schemes for the single-user and multi-user THz band networks are developed. Fifth, a three-dimensional (3-D) end-to-end model is developed and characterized, which includes the responses of the graphene-based reflectarray antenna and the 3-D multi-path propagation. The provided physical layer analysis in this thesis lays out the foundation for reliable and efficient ultra-high-speed
wireless communications in the THz band.
Advisors/Committee Members: Akyildiz, Ian F. (committee member), Li, Geoffrey Ye (committee member), Weitnauer, Mary Ann (committee member), Sivakumar, Raghupathy (committee member), Jornet, Josep Miquel (committee member).
Subjects/Keywords: Terahertz band; Wireless communications
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APA ·
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MLA ·
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APA (6th Edition):
Han, C. (2016). Physical layer solutions for ultra-broadband wireless communications in the terahertz band. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54965
Chicago Manual of Style (16th Edition):
Han, Chong. “Physical layer solutions for ultra-broadband wireless communications in the terahertz band.” 2016. Doctoral Dissertation, Georgia Tech. Accessed March 04, 2021.
http://hdl.handle.net/1853/54965.
MLA Handbook (7th Edition):
Han, Chong. “Physical layer solutions for ultra-broadband wireless communications in the terahertz band.” 2016. Web. 04 Mar 2021.
Vancouver:
Han C. Physical layer solutions for ultra-broadband wireless communications in the terahertz band. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/1853/54965.
Council of Science Editors:
Han C. Physical layer solutions for ultra-broadband wireless communications in the terahertz band. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/54965
University of Waterloo
16.
Berna, Gedik.
Channel estimation for Amplify and Forward Channels.
Degree: 2008, University of Waterloo
URL: http://hdl.handle.net/10012/3688
Cooperative diversity has been proposed as a powerful means to enhance the performance of high-rate communications over wireless fading channels. It realizes spatial diversity advantages in a distributed manner where two or more nodes share their antennas to mimic a virtual antenna array.
Subjects/Keywords: wireless communications
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Berna, G. (2008). Channel estimation for Amplify and Forward Channels. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/3688
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):
Berna, Gedik. “Channel estimation for Amplify and Forward Channels.” 2008. Thesis, University of Waterloo. Accessed March 04, 2021.
http://hdl.handle.net/10012/3688.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Berna, Gedik. “Channel estimation for Amplify and Forward Channels.” 2008. Web. 04 Mar 2021.
Vancouver:
Berna G. Channel estimation for Amplify and Forward Channels. [Internet] [Thesis]. University of Waterloo; 2008. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/10012/3688.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Berna G. Channel estimation for Amplify and Forward Channels. [Thesis]. University of Waterloo; 2008. Available from: http://hdl.handle.net/10012/3688
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Waterloo
17.
Soni, Jaimal.
Capacity Characterization of a MIMO-OFDM Wireless Channel with BLAST Implementation.
Degree: 2010, University of Waterloo
URL: http://hdl.handle.net/10012/5426
► As the data rates and performance of current telecommunications technologies reach their limits, MIMO offers promising results allowing for higher spectral efficiencies (or capacities) through…
(more)
▼ As the data rates and performance of current telecommunications technologies reach their limits, MIMO offers promising results allowing for higher spectral efficiencies (or capacities) through the use of multiple element antennas (MEAs). Conventional testing methods, however, cannot be used for multi-antenna systems due to the co-dependence of antenna and RF effects, and baseband hardware and software design. This dissertation specifies a novel MIMO-OFDM, BLAST-based testing design using a hybrid FPGA/DSP development platform from Lyrtech. The design allows for rapid implementation and a consistent indication of the channel impulse response. In addition, a multipath environment is further created to mimic a realistic high scattering scenario. A study of MIMO system capacity is performed along with measurements of an actual over-the-air (OTA) channel. Observations about capacity and the effect of MEA antenna separations are then drawn and conclusions made as to the overall ability to effectively test MIMO systems. The platform used is the result of efforts from several individuals within UW's CST group. My contributions and research are documented in this dissertation.
Subjects/Keywords: Wireless Communications
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APA (6th Edition):
Soni, J. (2010). Capacity Characterization of a MIMO-OFDM Wireless Channel with BLAST Implementation. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/5426
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):
Soni, Jaimal. “Capacity Characterization of a MIMO-OFDM Wireless Channel with BLAST Implementation.” 2010. Thesis, University of Waterloo. Accessed March 04, 2021.
http://hdl.handle.net/10012/5426.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Soni, Jaimal. “Capacity Characterization of a MIMO-OFDM Wireless Channel with BLAST Implementation.” 2010. Web. 04 Mar 2021.
Vancouver:
Soni J. Capacity Characterization of a MIMO-OFDM Wireless Channel with BLAST Implementation. [Internet] [Thesis]. University of Waterloo; 2010. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/10012/5426.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Soni J. Capacity Characterization of a MIMO-OFDM Wireless Channel with BLAST Implementation. [Thesis]. University of Waterloo; 2010. Available from: http://hdl.handle.net/10012/5426
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Queens University
18.
Abu Alkheir, Ala.
Cooperative Cognitive Radio Networks: Spectrum Acquisition and Co-Channel Interference Effect
.
Degree: Electrical and Computer Engineering, 2013, Queens University
URL: http://hdl.handle.net/1974/7808
► Cooperative Spectrum Sensing (CSS) allows Cognitive Radio Networks (CRNs) to locate vacant spectrum channels and to protect active Primary Users (PUs). However, the achieved detection…
(more)
▼ Cooperative Spectrum Sensing (CSS) allows Cognitive Radio Networks (CRNs) to locate vacant spectrum channels and to protect active Primary Users (PUs). However, the achieved detection accuracy is proportional to the duration of the CSS process which, unfortunately, reduces the time of useful communication as well as increases the Co-Channel Interference (CCI) perceived by an active PU. To overcome this, this thesis proposes three CSS strategies, namely the Dual-Threshold CSS (DTCSS), the Maximum CSS (MCSS), and the Max-Min CSS (MMCSS). These strategies reduce the number of reporting terminals while maintaining reliable performance and minimal CCI effect. The performance of these three methods is analyzed, and the numerical and simulations results illustrate the accuracy of the derived results as well as the achieved performance gains. The second part of this thesis studies the impact of CCI on the performance of a number of transmission techniques used by CRNs. These are Chase combining Hybrid Automatic Repeat Request (HAQR), Fixed Relaying (FR), Selective Relaying (SR), Incremental Relaying (IR), and Selective Incremental Relaying (SIR). The performance of these techniques is studied in terms of the average spectral efficiency, the outage probability, and the error probability. To obtain closed forms for the error probabilities, this thesis proposes a novel accurate approximation of the exponential integral function using a sum of exponentials.
Subjects/Keywords: Cognitive Radio
;
Wireless Communications
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APA (6th Edition):
Abu Alkheir, A. (2013). Cooperative Cognitive Radio Networks: Spectrum Acquisition and Co-Channel Interference Effect
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/7808
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):
Abu Alkheir, Ala. “Cooperative Cognitive Radio Networks: Spectrum Acquisition and Co-Channel Interference Effect
.” 2013. Thesis, Queens University. Accessed March 04, 2021.
http://hdl.handle.net/1974/7808.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Abu Alkheir, Ala. “Cooperative Cognitive Radio Networks: Spectrum Acquisition and Co-Channel Interference Effect
.” 2013. Web. 04 Mar 2021.
Vancouver:
Abu Alkheir A. Cooperative Cognitive Radio Networks: Spectrum Acquisition and Co-Channel Interference Effect
. [Internet] [Thesis]. Queens University; 2013. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/1974/7808.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Abu Alkheir A. Cooperative Cognitive Radio Networks: Spectrum Acquisition and Co-Channel Interference Effect
. [Thesis]. Queens University; 2013. Available from: http://hdl.handle.net/1974/7808
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Sydney
19.
Egan, Malcolm.
Resource allocation and feedback in wireless multiuser networks
.
Degree: 2013, University of Sydney
URL: http://hdl.handle.net/2123/10200
► This thesis focuses on the design of algorithms for resource allocation and feedback in wireless multiuser and heterogeneous networks. In particular, three key design challenges…
(more)
▼ This thesis focuses on the design of algorithms for resource allocation and feedback in wireless multiuser and heterogeneous networks. In particular, three key design challenges expected to have a major impact on future wireless networks are considered: cross-layer scheduling; structured quantization codebook design for MU-MIMO networks with limited feedback; and resource allocation to provide physical layer security. The first design challenge is cross-layer scheduling, where policies are proposed for two network architectures: user scheduling in single-cell multiuser networks aided by a relay; and base station (BS) scheduling in CoMP. These scheduling policies are then analyzed to guarantee satisfaction of three performance metrics: SEP; packet delay; and packet loss probability (PLP) due to buffer overflow. The concept of the τ-achievable PLP region is also introduced to explicitly describe the tradeoff in PLP between different users. The second design challenge is structured quantization codebook design in wireless networks with limited feedback, for both MU-MIMO and CoMP. In the MU-MIMO network, two codebook constructions are proposed, which are based on structured transformations of a base codebook. In the CoMP network, a low-complexity construction is proposed to solve the problem of variable codebook dimensions due to changes in the number of coordinated BSs. The proposed construction is shown to have comparable performance with the standard approach based on a random search, while only requiring linear instead of exponential complexity. The final design challenge is resource allocation for physical layer security in MU-MIMO. To guarantee physical layer security, the achievable secrecy sum-rate is explicitly derived for the regularized channel inversion (RCI) precoder. To improve performance, power allocation and precoder design are jointly optimized using a new algorithm based on convex optimization techniques.
Subjects/Keywords: Wireless communications;
MIMO;
Scheduling
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APA (6th Edition):
Egan, M. (2013). Resource allocation and feedback in wireless multiuser networks
. (Thesis). University of Sydney. Retrieved from http://hdl.handle.net/2123/10200
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):
Egan, Malcolm. “Resource allocation and feedback in wireless multiuser networks
.” 2013. Thesis, University of Sydney. Accessed March 04, 2021.
http://hdl.handle.net/2123/10200.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Egan, Malcolm. “Resource allocation and feedback in wireless multiuser networks
.” 2013. Web. 04 Mar 2021.
Vancouver:
Egan M. Resource allocation and feedback in wireless multiuser networks
. [Internet] [Thesis]. University of Sydney; 2013. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/2123/10200.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Egan M. Resource allocation and feedback in wireless multiuser networks
. [Thesis]. University of Sydney; 2013. Available from: http://hdl.handle.net/2123/10200
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Texas – Austin
20.
Khan, Talha Ahmed.
Analysis and design of energy harvesting wireless communication systems.
Degree: PhD, Electrical and Computer Engineering, 2018, University of Texas – Austin
URL: http://hdl.handle.net/2152/63697
► Wireless-powered communication is an emerging technology for powering the large number of miniature devices of the future. In a wireless-powered communication system, low-power sensors extract…
(more)
▼ Wireless-powered communication is an emerging technology for powering the
large number of miniature devices of the future. In a
wireless-powered communication system, low-power sensors extract energy from the incident
wireless signals to
power their operations such as information transmission, sensing or reception. Due to sporadic energy availability, however, such a system is fundamentally different from
a traditionally-powered communication system. This dissertation investigates three distinct aspects of
wireless-powered
communications to get insights on the system operation. First, leveraging concepts from finite-length information theory, an analytical framework is developed for examining
wireless-powered
communications with short packets, i.e., in the finite blocklength regime. This is relevant as remotely-powered
communications may entail short packets due to small payloads, low-latency requirements, or limited energy to support a longer transmission. Second, using a stochastic geometry framework, an analytical model is developed for characterizing the performance of
wireless-powered
communications in the millimeter wave (mmWave) band. The proposed model incorporates the key features of mmWave systems such as directional beamforming and sensitivity to building blockages. Finally, the power transfer efficiency and the energy efficiency of a
wireless-powered communication system aided by massive MIMO is characterized. The broad goal of this dissertation is to better understand
wireless-powered
communications in the context of the emerging technologies for 5G.
Advisors/Committee Members: Heath, Robert W., Jr, 1973- (advisor), Andrews, Jeffrey G (committee member), Thomaz Jr., Edison (committee member), Vikalo, Haris (committee member), Orlik, Philip (committee member).
Subjects/Keywords: Energy harvesting; Wireless-powered communications
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APA (6th Edition):
Khan, T. A. (2018). Analysis and design of energy harvesting wireless communication systems. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/63697
Chicago Manual of Style (16th Edition):
Khan, Talha Ahmed. “Analysis and design of energy harvesting wireless communication systems.” 2018. Doctoral Dissertation, University of Texas – Austin. Accessed March 04, 2021.
http://hdl.handle.net/2152/63697.
MLA Handbook (7th Edition):
Khan, Talha Ahmed. “Analysis and design of energy harvesting wireless communication systems.” 2018. Web. 04 Mar 2021.
Vancouver:
Khan TA. Analysis and design of energy harvesting wireless communication systems. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2018. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/2152/63697.
Council of Science Editors:
Khan TA. Analysis and design of energy harvesting wireless communication systems. [Doctoral Dissertation]. University of Texas – Austin; 2018. Available from: http://hdl.handle.net/2152/63697
University of Oklahoma
21.
Zhou, Dayong.
WIRELESS OPTICAL TRANSCEIVER DESIGN, LINK ANALISYS AND ALIGNMENT CONTROL FOR MOBILE COMMUNICATION.
Degree: PhD, 2013, University of Oklahoma
URL: http://hdl.handle.net/11244/318748
► Pointing, acquisition and tracking of a free-space optical node in a mobile network experiencing misalignment due to adverse factors including vibration, motion and atmospheric turbulence…
(more)
▼ Pointing, acquisition and tracking of a free-space optical node in a mobile network experiencing misalignment due to adverse factors including vibration, motion and atmospheric turbulence requires a different approach than traditional free-space optical transceivers. A recent fiber-bundle approach for beam steering at the transmitter was investigated to provide continuous beam coverage at the receiver without the application of mechanical devices. Utilizing multiple fibers-lenses sets at the receiver was also proposed to enhance the tolerance of optical link misalignment. In this work, both laboratory experiments and software simulation were implemented to evaluate the optical link performance for different fiber-bundle-based transceiver setups as the link parameters were varied. The performance was evaluated in terms of the coverage area at the receiver, which is a measure of misalignment tolerance and is dependent not only on wavelength but on other key parameters such as link length, transmitted power, the pattern of transmitters, beam divergence, and the receiver construction. The results showed that fiber-bindle-based transceivers reveal significant potential to maximize the up time of the link, and the results also provide guidance on the further development of the overall system. To incorporate the proposed transceiver designs, an alignment control system was developed and evaluated as well. The laboratory results show that the optical control system successfully recovered and maintained the link while the receiver was in motion and the signal coverage at the target area was enhanced significantly.
Advisors/Committee Members: Refai, Hazem H.||LoPresti, Peter G. (advisor).
Subjects/Keywords: Optical communications; Wireless communication systems
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APA ·
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Manager
APA (6th Edition):
Zhou, D. (2013). WIRELESS OPTICAL TRANSCEIVER DESIGN, LINK ANALISYS AND ALIGNMENT CONTROL FOR MOBILE COMMUNICATION. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/318748
Chicago Manual of Style (16th Edition):
Zhou, Dayong. “WIRELESS OPTICAL TRANSCEIVER DESIGN, LINK ANALISYS AND ALIGNMENT CONTROL FOR MOBILE COMMUNICATION.” 2013. Doctoral Dissertation, University of Oklahoma. Accessed March 04, 2021.
http://hdl.handle.net/11244/318748.
MLA Handbook (7th Edition):
Zhou, Dayong. “WIRELESS OPTICAL TRANSCEIVER DESIGN, LINK ANALISYS AND ALIGNMENT CONTROL FOR MOBILE COMMUNICATION.” 2013. Web. 04 Mar 2021.
Vancouver:
Zhou D. WIRELESS OPTICAL TRANSCEIVER DESIGN, LINK ANALISYS AND ALIGNMENT CONTROL FOR MOBILE COMMUNICATION. [Internet] [Doctoral dissertation]. University of Oklahoma; 2013. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/11244/318748.
Council of Science Editors:
Zhou D. WIRELESS OPTICAL TRANSCEIVER DESIGN, LINK ANALISYS AND ALIGNMENT CONTROL FOR MOBILE COMMUNICATION. [Doctoral Dissertation]. University of Oklahoma; 2013. Available from: http://hdl.handle.net/11244/318748
Brunel University
22.
Zettas, Spiridon.
Adaptive averaging channel estimation for DVB-T2 systems.
Degree: PhD, 2018, Brunel University
URL: http://bura.brunel.ac.uk/handle/2438/16581
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.765002
► In modern communication systems, the rate of transmitted data is growing rapidly. This leads to the need for more sophisticated methods and techniques of implementation…
(more)
▼ In modern communication systems, the rate of transmitted data is growing rapidly. This leads to the need for more sophisticated methods and techniques of implementation in every block of the transmitter-receiver chain. The weakest link in radio communications is the transmission channel. The signal, which is passed through it, suffers from many degrading factors like noise, attenuation, diffraction, scattering etc. In the receiver side, the modulated signal has to be restored to its initial state in order to extract the useful information. Assuming that the channel acts like a filter with finite impulse, one has to know its coefficients in order to apply the inverse function, which will restore the signal back to its initial state. The techniques which deal with this problem are called channel estimation. Noise is one of the causes that degrade the quality of the received signal. If it could be discarded, then the process of channel estimation would be easier. Transmitting special symbols, called pilots with known amplitude, phase and position to the receiver and assuming that the noise has zero mean, an averaging process could reduce the noise impact to the pilot amplitudes and thus simplify the channel estimation process. In this thesis, a novel channel estimation method based on noise rejection is introduced. The estimator takes into account the time variations of the channel and adapts its buffer size in order to achieve the best performance. Many configurations of the estimator were tested and at the beginning of the research fixed size estimators were tested. The fixed estimator has a very good performance for channels which could be considered as stationary in the time domain, like Additive White Gaussian Noise (AWGN) channels or slowly time-varying channels. AWGN channel is a channel model where the only distorting factor is the noise, where noise is every unwanted signal interfering with the useful signal. The properties of the noise are that it is additive, which means that the noise is superimposed on the transmitted signal, it is white so the power density is constant for all frequencies, and it has a Gaussian distribution in the time domain with zero mean and variance σ2=N. A slowly time varying channel refers to channel with coherence time larger than the transmitted symbol duration. The performance of a fixed size averaging estimator in case of fast time-varying channels is subject to the buffering time. When the buffering time is smaller or equal to a portion of the coherence time the averaging process offers better performance than the conventional estimation, but when the buffering time exceeds this portion of the coherence time the performance of the averaging process degrades fast. So, an extension has been made to the averaging estimator that estimates the Doppler shift and thus the coherence time, where the channel could be assumed as stationary. The improved estimator called Adaptive Averaging Channel Estimator (AACE) is capable to adjust its buffer size and thus to average only successive…
Subjects/Keywords: 621.382; Wireless communications; Doppler Shift
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APA (6th Edition):
Zettas, S. (2018). Adaptive averaging channel estimation for DVB-T2 systems. (Doctoral Dissertation). Brunel University. Retrieved from http://bura.brunel.ac.uk/handle/2438/16581 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.765002
Chicago Manual of Style (16th Edition):
Zettas, Spiridon. “Adaptive averaging channel estimation for DVB-T2 systems.” 2018. Doctoral Dissertation, Brunel University. Accessed March 04, 2021.
http://bura.brunel.ac.uk/handle/2438/16581 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.765002.
MLA Handbook (7th Edition):
Zettas, Spiridon. “Adaptive averaging channel estimation for DVB-T2 systems.” 2018. Web. 04 Mar 2021.
Vancouver:
Zettas S. Adaptive averaging channel estimation for DVB-T2 systems. [Internet] [Doctoral dissertation]. Brunel University; 2018. [cited 2021 Mar 04].
Available from: http://bura.brunel.ac.uk/handle/2438/16581 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.765002.
Council of Science Editors:
Zettas S. Adaptive averaging channel estimation for DVB-T2 systems. [Doctoral Dissertation]. Brunel University; 2018. Available from: http://bura.brunel.ac.uk/handle/2438/16581 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.765002
Hong Kong University of Science and Technology
23.
Zhou, Zimu.
Boosting WiFi sensing with physical layer information.
Degree: 2015, Hong Kong University of Science and Technology
URL: http://repository.ust.hk/ir/Record/1783.1-80134
;
https://doi.org/10.14711/thesis-b1552252
;
http://repository.ust.hk/ir/bitstream/1783.1-80134/1/th_redirect.html
► The growing PHY layer capabilities of WiFi has made it possible to reuse WiFi signals for sensing. Sensing via WiFi enables remote sensing without wearable…
(more)
▼ The growing PHY layer capabilities of WiFi has made it possible to reuse WiFi signals for sensing. Sensing via WiFi enables remote sensing without wearable sensors and contactless sensing in privacy-preserving mode, which are beneficial in various applications including security surveillance, intrusion detection, elderly monitoring, and human-computer interaction. For WiFi sensing to excel indoors, multipath propagation acts as a major concern. The multipath effect can invalidate theoretical propagation models, distort received signal signatures, and constrain the performance of wireless sensing even when inferring the presence of humans. To explicitly eliminate any adverse impact of multipath propagation, researchers resort to customized signals and specialized software-defined radios for radar signal processing. To enable device-free applications on commodity infrastructures, existing approaches exploit a dense deployment of wireless links. Instead of avoiding multipath, in this thesis, we demonstrate it is possible to harness multipath in WiFi sensing with the PHY layer Channel State Information (CSI). First, we design a primitive to identify the availability of the LOS path under multipath propagation with only commodity WiFi devices to improve the multipath awareness in WiFi sensing. Second, we exploit the rich multipath effect as fingerprints to blur the directional coverage of traditional passive human detection architecture to achieve omnidirectional coverage. Third, we propose a measurable metric as proxy for detection sensitivity and a lightweight subcarrier and path configuration scheme to adapt to different multipath propagation conditions. Finally, we design a unified framework for both static and moving human detection, by capturing the chest movements of static humans. We prototype the above schemes with commodity WiFi infrastructure, and evaluate their performances in typical office environments. Experimental results demonstrate improved detection accuracy, coverage and sensitivity compared with MAC layer RSSI based schemes.
Subjects/Keywords: Radio resource management (Wireless communications)
; Wireless sensor networks
; Wireless communication systems
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APA (6th Edition):
Zhou, Z. (2015). Boosting WiFi sensing with physical layer information. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-80134 ; https://doi.org/10.14711/thesis-b1552252 ; http://repository.ust.hk/ir/bitstream/1783.1-80134/1/th_redirect.html
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):
Zhou, Zimu. “Boosting WiFi sensing with physical layer information.” 2015. Thesis, Hong Kong University of Science and Technology. Accessed March 04, 2021.
http://repository.ust.hk/ir/Record/1783.1-80134 ; https://doi.org/10.14711/thesis-b1552252 ; http://repository.ust.hk/ir/bitstream/1783.1-80134/1/th_redirect.html.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zhou, Zimu. “Boosting WiFi sensing with physical layer information.” 2015. Web. 04 Mar 2021.
Vancouver:
Zhou Z. Boosting WiFi sensing with physical layer information. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2015. [cited 2021 Mar 04].
Available from: http://repository.ust.hk/ir/Record/1783.1-80134 ; https://doi.org/10.14711/thesis-b1552252 ; http://repository.ust.hk/ir/bitstream/1783.1-80134/1/th_redirect.html.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zhou Z. Boosting WiFi sensing with physical layer information. [Thesis]. Hong Kong University of Science and Technology; 2015. Available from: http://repository.ust.hk/ir/Record/1783.1-80134 ; https://doi.org/10.14711/thesis-b1552252 ; http://repository.ust.hk/ir/bitstream/1783.1-80134/1/th_redirect.html
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
24.
Mohapatra, Parthajit.
Fundamentals Limits Of Communication In Interference Limited Environments.
Degree: PhD, Faculty of Engineering, 2017, Indian Institute of Science
URL: http://etd.iisc.ac.in/handle/2005/2652
► In multiuser wireless communications, interference not only limits the performance of the system, but also allows users to eavesdrop on other users’ messages. Hence, interference…
(more)
▼ In multiuser
wireless communications, interference not only limits the performance of the system, but also allows users to eavesdrop on other users’ messages. Hence, interference management in multiuser
wireless communication has received significant attention in the last decade, both in the academia and industry. The interference channel (IC) is one of the simplest information theoretic models to analyze the effect of interference on the throughput and secrecy of individual messages in a multiuser setup. In this thesis, the IC is studied under different settings with and without the secrecy constraint. The main contributions of the thesis are as follows:
• The generalized degrees of freedom (GDOF) has emerged as a useful approximate measure of the potential throughput of a multiuser
wireless system. Also, multiple antennas at the transmitter and receiver can provide additional dimension for signaling, which can in turn improve the GDOF performance of the IC. In the initial part of the thesis, a K-user MIMO Gaussian IC (GIC) is studied from an achievable GDOF perspective. An inner bound on GDOF is derived using a combination of techniques such as treating interference as noise, zero-forcing receiving, interference alignment (IA), and extending the Han-Kobayashi (HK) scheme to K users. Also, outer bounds on the sum rate of the K-user MIMO GIC are derived, under different assumptions of cooperation and providing side information to the receivers. The derived outer bounds are simplified to obtain outer bounds on the GDOF. The relative performance of these bounds yields insight into the performance limits of the multiuser MIMO GIC and the relative merits of different schemes for interference management.
• Then, the problem of designing the precoding and receive filtering matrices for IA is explored for K-user MIMO (M × N) GIC. Two algorithms for designing the precoding and receive filtering matrices for IA in the block fading or constant MIMO IC with a finite number of symbol extensions are proposed. The first algorithm for IA is based on aligning a subset of the interfering signal streams at each receiver. As the first algorithm requires global channel knowledge at each node, a distributed algorithm is proposed which requires only limited channel knowledge at each node. A new performance metric is proposed, that captures the possible loss in signal dimension while designing the precoders. The performance of the algorithms are evaluated by comparing them with existing algorithms for IA precoder design.
• In the later part of the thesis, a 2-user IC with limited-rate transmitter cooperation is studied, to investigate the role of cooperation in managing interference and ensuring secrecy. First, the problem is studied in the deterministic setting, and achievable schemes are proposed, which use a combination of interference cancelation, relaying of the other user’s data bits, time sharing, and transmission of random bits, depending on the rate of the cooperative link and the relative strengths of the signal and the…
Advisors/Committee Members: Murthy, Chandra R (advisor).
Subjects/Keywords: Wireless Communication; Interference Channel; Interference Limited Wireless Communications; Multiuser Wireless Communications; K-User MIMO Gaussian Interference Channel; Interference (Wireless Communications); Information Theory; Multiuser Wireless Communications; Communication Engineering
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APA (6th Edition):
Mohapatra, P. (2017). Fundamentals Limits Of Communication In Interference Limited Environments. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2652
Chicago Manual of Style (16th Edition):
Mohapatra, Parthajit. “Fundamentals Limits Of Communication In Interference Limited Environments.” 2017. Doctoral Dissertation, Indian Institute of Science. Accessed March 04, 2021.
http://etd.iisc.ac.in/handle/2005/2652.
MLA Handbook (7th Edition):
Mohapatra, Parthajit. “Fundamentals Limits Of Communication In Interference Limited Environments.” 2017. Web. 04 Mar 2021.
Vancouver:
Mohapatra P. Fundamentals Limits Of Communication In Interference Limited Environments. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2017. [cited 2021 Mar 04].
Available from: http://etd.iisc.ac.in/handle/2005/2652.
Council of Science Editors:
Mohapatra P. Fundamentals Limits Of Communication In Interference Limited Environments. [Doctoral Dissertation]. Indian Institute of Science; 2017. Available from: http://etd.iisc.ac.in/handle/2005/2652
25.
Raphika, P. M.
Design and Development of Planar Lowpass Filters with Sharp Roll-off and Wide Stopband for RF and Wireless Communication Systems.
Degree: 2016, Cochin University of Science and Technology
URL: http://dyuthi.cusat.ac.in/purl/5170
► Filters are one of the essential components in the RF and wireless communication systems. Small sized planar lowpass filters with good electrical characteristics along with…
(more)
▼ Filters are one of the essential components in the RF and wireless
communication systems. Small sized planar lowpass filters with good electrical
characteristics along with low cost, light weight and ease of fabrication are highly
desirable for the front end of modern communication systems to suppress harmonics
and spurious signals. Design of compact lowpass filters with improved performance
and diverse specifications for numerous applications is a huge challenge.
In this thesis, high performance planar compact lowpass filters using multiple
patch resonators on high impedance transmission line are developed. Design techniques
of different types of patch resonators and their modifications to enhance the
performance of the filters are presented.Patch resonators are designed by using high impedance short circuited stubs
and low impedance open circuited patches. In the first stage of filter realization,
compact lowpass filter having sharp roll-off using triangular and funnel patch
resonators is presented. The structure is modified further to enhance the relative
stopband bandwidth of the filter. In the third stage, another resonator has been
introduced near the feed line to achieve sharp roll-off for the same cutoff frequency,
stopband bandwidth and suppression level. To obtain compactness, high suppression
level and wide stopband in filter design, low thickness substrate is tested and proved in
the fourth stage.
Realizations of planar compact lowpass filter with very sharp roll-off near the
cutoff frequency have been presented using stepped impedance polygonal patch
resonators. By increasing the patch size and number of resonators, the stopband
bandwidth and suppression level have to be enhanced to a great extent. Enhancement
of performance characteristics of lowpass filter design is continually being extended.
By using high value capacitance patch, the stopband suppression level of the filter with
sharp roll-off rate is achieved. Elliptic function lowpass filter with ultra-sharp roll-off is
also developed using elliptic shaped patch resonators.
Throughout the study, low cost substrate having permittivity 4.4 is used for the
filter design. All the designed filters have been fabricated and predicted results are
validated by the measurements.
Subjects/Keywords: Radio Frequency; Wireless communications; Patch resonators; Filters
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APA (6th Edition):
Raphika, P. M. (2016). Design and Development of Planar Lowpass Filters with Sharp Roll-off and Wide Stopband for RF and Wireless Communication Systems. (Thesis). Cochin University of Science and Technology. Retrieved from http://dyuthi.cusat.ac.in/purl/5170
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):
Raphika, P M. “Design and Development of Planar Lowpass Filters with Sharp Roll-off and Wide Stopband for RF and Wireless Communication Systems.” 2016. Thesis, Cochin University of Science and Technology. Accessed March 04, 2021.
http://dyuthi.cusat.ac.in/purl/5170.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Raphika, P M. “Design and Development of Planar Lowpass Filters with Sharp Roll-off and Wide Stopband for RF and Wireless Communication Systems.” 2016. Web. 04 Mar 2021.
Vancouver:
Raphika PM. Design and Development of Planar Lowpass Filters with Sharp Roll-off and Wide Stopband for RF and Wireless Communication Systems. [Internet] [Thesis]. Cochin University of Science and Technology; 2016. [cited 2021 Mar 04].
Available from: http://dyuthi.cusat.ac.in/purl/5170.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Raphika PM. Design and Development of Planar Lowpass Filters with Sharp Roll-off and Wide Stopband for RF and Wireless Communication Systems. [Thesis]. Cochin University of Science and Technology; 2016. Available from: http://dyuthi.cusat.ac.in/purl/5170
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Alberta
26.
Hemachandra, Kasun Thilina.
A mathematical framework for expressing multivariate
distributions useful in wireless communications.
Degree: MS, Department of Electrical and Computer
Engineering, 2010, University of Alberta
URL: https://era.library.ualberta.ca/files/df65v9119
► Multivariate statistics play an important role in performance analysis of wireless communication systems in correlated fading channels. This thesis presents a framework which can be…
(more)
▼ Multivariate statistics play an important role in
performance analysis of wireless communication systems in
correlated fading channels. This thesis presents a framework which
can be used to derive easily computable mathematical
representations for some multivariate statistical distributions,
which are derivatives of the Gaussian distribution, and which have
a particular correlation structure. The new multivariate
distribution representations are given as single integral solutions
of familiar mathematical functions which can be evaluated using
common mathematical software packages. The new approach can be used
to obtain single integral representations for the multivariate
probability density function, cumulative distribution function, and
joint moments of some widely used statistical distributions in
wireless communication theory, under an assumed correlation
structure. The remarkable advantage of the new representation is
that the computational burden remains at numerical evaluation of a
single integral, for a distribution with an arbitrary number of
dimensions. The new representations are used to evaluate the
performance of diversity combining schemes and multiple input
multiple output systems, operating in correlated fading channels.
The new framework gives some insights into some long existing open
problems in multivariate statistical distributions.
Subjects/Keywords: Multivariate statistics; Multiple antenna systems; Wireless communications
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APA (6th Edition):
Hemachandra, K. T. (2010). A mathematical framework for expressing multivariate
distributions useful in wireless communications. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/df65v9119
Chicago Manual of Style (16th Edition):
Hemachandra, Kasun Thilina. “A mathematical framework for expressing multivariate
distributions useful in wireless communications.” 2010. Masters Thesis, University of Alberta. Accessed March 04, 2021.
https://era.library.ualberta.ca/files/df65v9119.
MLA Handbook (7th Edition):
Hemachandra, Kasun Thilina. “A mathematical framework for expressing multivariate
distributions useful in wireless communications.” 2010. Web. 04 Mar 2021.
Vancouver:
Hemachandra KT. A mathematical framework for expressing multivariate
distributions useful in wireless communications. [Internet] [Masters thesis]. University of Alberta; 2010. [cited 2021 Mar 04].
Available from: https://era.library.ualberta.ca/files/df65v9119.
Council of Science Editors:
Hemachandra KT. A mathematical framework for expressing multivariate
distributions useful in wireless communications. [Masters Thesis]. University of Alberta; 2010. Available from: https://era.library.ualberta.ca/files/df65v9119
Penn State University
27.
Alqudah, Yazan A.
Space Diversity in Indoor Broadband Optical Wireless Communications.
Degree: 2008, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/6086
► Wireless optical (infrared) link provides a secure and a promising alternative to radio for wireless indoor connectivity, be it for terminals or sensors. The large…
(more)
▼ Wireless optical (infrared) link provides a secure and a promising alternative to radio for
wireless indoor connectivity, be it for terminals or sensors. The large spectrum of unregulated band enables a link to provide broadband access needed for multimedia and other bandwidth demanding applications. The spatial confinement of infrared light provides interference-free bandwidth-reuse in adjacent rooms. The ability to create spatially independent channels in a small physical space holds the promise of large link capacity.
The main challenges in the design of an infrared link include: susceptibility to shadowing, multipath dispersion, and limited range resulting from noise generated by ambient light. Shadowing caused by benign objects blocking signal path results in service degradation, if not complete interruption. Configurations employing wide beam transmitter to service many receiver locations suffer multipath. Noise at receiver is generated by ambient light. Even in a uniformly lit environment, noise generated by natural and artificial light varies depending on receiver location and orientation.
To combat the adverse effects of temporal dispersion in high-speed applications, an accurate channel impulse response is needed. The impulse response is used to analyze and to compensate for the effects of multipath dispersion. In this work, a new approach for obtaining the channel impulse response is presented resulting in tremendous savings in calculation time and bringing insight into the channel behavior.
The ability to create spatially independent channels has motivated a new configuration called Multi-Spot Diffusing (MSD) configuration. In which, a transmitter acts as an array antenna, with each element transmitting data over an independent channel. A multibranch receiver is employed to receive independent copies of transmitted data through each of its branches. In our research, we analyze MSD link with the objective of determining the optimal number of branches that results in maximum signal-to-noise ratio, minimum probability of error and minimum outage probability.
The MSD configuration increases link capacity and reliability by providing a multi-input multi-output channel between transceivers. The availability of N spatial channels implies the possibility of increasing data rate by N folds compared to a single channel. In order to improve link reliability, our research considers novel spatial diversity coding techniques. In orthogonal spatial coding, each channel is responsible for carrying one of N symbols. The receiver decides on a transmitted symbol by comparing received signals on its branches and selects the branch corresponding to maximum signal. In another proposed scheme, a symbol is represented by N bit code word. Each bit is transmitted through a separate channel. The diversity receiver decides on a symbol that corresponds to the highest correlation with a received code word. Thus, information is transmitted not only through signal shapes, but also through branches that receive them.
Traditionally, a…
Advisors/Committee Members: Mohsen Kavehrad, Committee Chair/Co-Chair, John Metzner, Committee Member, Shizhuo Yin, Committee Member, Natarajan Gautam, Committee Member.
Subjects/Keywords: Optical Wireless Communications
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APA (6th Edition):
Alqudah, Y. A. (2008). Space Diversity in Indoor Broadband Optical Wireless Communications. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/6086
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):
Alqudah, Yazan A. “Space Diversity in Indoor Broadband Optical Wireless Communications.” 2008. Thesis, Penn State University. Accessed March 04, 2021.
https://submit-etda.libraries.psu.edu/catalog/6086.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Alqudah, Yazan A. “Space Diversity in Indoor Broadband Optical Wireless Communications.” 2008. Web. 04 Mar 2021.
Vancouver:
Alqudah YA. Space Diversity in Indoor Broadband Optical Wireless Communications. [Internet] [Thesis]. Penn State University; 2008. [cited 2021 Mar 04].
Available from: https://submit-etda.libraries.psu.edu/catalog/6086.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Alqudah YA. Space Diversity in Indoor Broadband Optical Wireless Communications. [Thesis]. Penn State University; 2008. Available from: https://submit-etda.libraries.psu.edu/catalog/6086
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Texas A&M University
28.
Vanaparthy, Santhosh Kumar.
Capacity-Achieving Coding Mechanisms: Spatial Coupling and Group Symmetries.
Degree: PhD, Electrical Engineering, 2015, Texas A&M University
URL: http://hdl.handle.net/1969.1/156291
► The broad theme of this work is in constructing optimal transmission mechanisms for a wide variety of communication systems. In particular, this dissertation provides a…
(more)
▼ The broad theme of this work is in constructing optimal transmission mechanisms for a wide variety of communication systems. In particular, this dissertation provides a proof of threshold saturation for spatially-coupled codes, low-complexity capacity-achieving coding schemes for side-information problems, a proof that Reed-Muller and primitive narrow-sense BCH codes achieve capacity on erasure channels, and a mathematical framework to design delay sensitive communication systems.
Spatially-coupled codes are a class of codes on graphs that are shown to achieve capacity universally over binary symmetric memoryless channels (BMS) under belief-propagation decoder. The underlying phenomenon behind spatial coupling, known as “threshold saturation via spatial coupling”, turns out to be general and this technique has been applied to a wide variety of systems. In this work, a proof of the threshold saturation phenomenon is provided for irregular low-density parity-check (LDPC) and low-density generator-matrix (LDGM) ensembles on BMS channels. This proof is far simpler than published alternative proofs and it remains as the only technique to handle irregular and LDGM codes. Also, low-complexity capacity-achieving codes are constructed for three coding problems via spatial coupling: 1) rate distortion with side-information, 2) channel coding with side-information, and 3) write-once memory system. All these schemes are based on spatially coupling compound LDGM/LDPC ensembles.
Reed-Muller and Bose-Chaudhuri-Hocquengham (BCH) are well-known algebraic codes introduced more than 50 years ago. While these codes are studied extensively in the literature it wasn’t known whether these codes achieve capacity. This work introduces a technique to show that Reed-Muller and primitive narrow-sense BCH codes achieve capacity on erasure channels under maximum a posteriori (MAP) decoding. Instead of relying on the weight enumerators or other precise details of these codes, this technique requires that these codes have highly symmetric permutation groups. In fact, any sequence of linear codes with increasing blocklengths whose rates converge to a number between 0 and 1, and whose permutation groups are doubly transitive achieve capacity on erasure channels under bit-MAP decoding. This pro-vides a rare example in information theory where symmetry alone is sufficient to achieve capacity.
While the channel capacity provides a useful benchmark for practical design, communication systems of the day also demand small latency and other link layer metrics. Such delay sensitive communication systems are studied in this work, where a mathematical framework is developed to provide insights into the optimal design of these systems.
Advisors/Committee Members: Chamberland, Jean-Francois (advisor), Pfister, Henry D (advisor), Shakkottai, Srinivas (committee member), Papanikolas, Matthew A (committee member).
Subjects/Keywords: Information Theory; Coding Theory; Wireless Communications
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APA (6th Edition):
Vanaparthy, S. K. (2015). Capacity-Achieving Coding Mechanisms: Spatial Coupling and Group Symmetries. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156291
Chicago Manual of Style (16th Edition):
Vanaparthy, Santhosh Kumar. “Capacity-Achieving Coding Mechanisms: Spatial Coupling and Group Symmetries.” 2015. Doctoral Dissertation, Texas A&M University. Accessed March 04, 2021.
http://hdl.handle.net/1969.1/156291.
MLA Handbook (7th Edition):
Vanaparthy, Santhosh Kumar. “Capacity-Achieving Coding Mechanisms: Spatial Coupling and Group Symmetries.” 2015. Web. 04 Mar 2021.
Vancouver:
Vanaparthy SK. Capacity-Achieving Coding Mechanisms: Spatial Coupling and Group Symmetries. [Internet] [Doctoral dissertation]. Texas A&M University; 2015. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/1969.1/156291.
Council of Science Editors:
Vanaparthy SK. Capacity-Achieving Coding Mechanisms: Spatial Coupling and Group Symmetries. [Doctoral Dissertation]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/156291
Northeastern University
29.
Galagarza Martinez, Edson Stevens.
Recent advances on physical layer security for wireless communications.
Degree: MS, Department of Electrical and Computer Engineering, 2018, Northeastern University
URL: http://hdl.handle.net/2047/D20291186
► Wireless communications are naturally exposed to important security risks due to their broadcast nature. In contrast with wired communications, no physical medium is isolating the…
(more)
▼ Wireless communications are naturally exposed to important security risks due to their broadcast nature. In contrast with wired communications, no physical medium is isolating the transmission surroundings to a specific path. Traditional methods to reach the goals of communications security rely on algorithms at protocol stack level, which are based on mathematically derived cryptographic protocols. With the tremendous proliferation of wireless devices, and the increase in computational power available for decryption, traditional cryptographic measures may be compromised. To protect communications at the lowest level, physical layer (PHY) security methods have been proposed recently. These techniques aim to ensure secure communications by exploiting the unique characteristics of the physical medium between communicating nodes, effectively reducing the decryption capabilities of an eavesdropper to intercept transmissions. This thesis explains within a general framework the most important PHY layer security schemes. First we explore approaches which utilize the knowledge of the unique channel between communicating nodes to distort a transmitted signal with various kinds of randomizations, in such a way that the intended receivers are unaffected by the distortion, but any other observer will be exposed to it. These techniques, however, introduce several trade-offs between transmission resources and the effectiveness in achieving secrecy. Of particular interest for this investigation is a class of methods which can be referred to as "security enhancing techniques", in which minimal priors about the potential eavesdroppers locations and capabilities are assumed. In this thesis, a wave-based approach to the communication secrecy problem is introduced. An interesting perspective is provided by studying the relation between electromagnetic theory and information theory, the so-called electromagnetic information theory. This allows to properly identify the unavoidable limitations imposed by the laws of electromagnetics to our ability to communicate securely. The proposed model can be extended to the analysis of different signal distortion methodologies and different channel conditions. The resulting approach is highly relevant to the study of PHY layer security methods since it is physically fundamental as well as architecture independent, which leads to a consolidating point of view of the secrecy problem. In addition, the thesis presents computer simulation results which shed insight on the security possibilities and limitations of three different security scenarios, which are termed MISO (multiple-input, single-output) (with single eavesdropper), MISOME (multiple-input, single-output, multiple eavesdropper), and MIMOME (multiple-input, multiple-output, multiple-eavesdropper).
Subjects/Keywords: physical layer security; wireless communications; security
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APA (6th Edition):
Galagarza Martinez, E. S. (2018). Recent advances on physical layer security for wireless communications. (Masters Thesis). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20291186
Chicago Manual of Style (16th Edition):
Galagarza Martinez, Edson Stevens. “Recent advances on physical layer security for wireless communications.” 2018. Masters Thesis, Northeastern University. Accessed March 04, 2021.
http://hdl.handle.net/2047/D20291186.
MLA Handbook (7th Edition):
Galagarza Martinez, Edson Stevens. “Recent advances on physical layer security for wireless communications.” 2018. Web. 04 Mar 2021.
Vancouver:
Galagarza Martinez ES. Recent advances on physical layer security for wireless communications. [Internet] [Masters thesis]. Northeastern University; 2018. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/2047/D20291186.
Council of Science Editors:
Galagarza Martinez ES. Recent advances on physical layer security for wireless communications. [Masters Thesis]. Northeastern University; 2018. Available from: http://hdl.handle.net/2047/D20291186
University of Manitoba
30.
Alsehaili, Mohammad.
Generalized Three Dimensional Geometrical Scattering Channel Model for Indoor and Outdoor Propagation Environments.
Degree: Electrical and Computer Engineering, 2011, University of Manitoba
URL: http://hdl.handle.net/1993/4384
► The well known geometrical scattering channel modeling technique has been suggested to describe the spatial statistical distribution of the received multipath signals at various types…
(more)
▼ The well known geometrical scattering channel modeling technique has been suggested to describe the spatial statistical
distribution of the received multipath signals at various types of
wireless communication environments and for different
wireless system
applications. This technique is based on the assumption that the scatterers, i.e. objects that give rise to the multipath signals, are
randomly distributed within a specified geometry that may include the base station and/or the mobile station. The geometrical scattering
channel models can provide convenient and simple statistical functions for some of the important physical quantities of the received
multipath fading signals, such as: angle of arrival, time of arrival, angular spread, delay spread and the spatial correlation function.
In this thesis, a new three dimensional geometrical scattering channel model has been developed for outdoor and indoor
wireless
communication environments. The probability density functions of the angle of arrival of the received multipath signals are provided in
compact forms. These functions facilitate independent control of the angular spread in both the azimuth and the elevation angles via the
model's parameters. To establish the model verification, the developed model has been compared against the results from a site-specific
propagation prediction technique in indoor and outdoor
wireless communication environments.
The developed three dimensional model has been extended to include the temporal statistical distribution of the received multipath signals
for uniform and non-uniform distributions of the scatterer. Several of the probability density functions of the angle of arrival and time of
arrival of the received multipath signals are provided. The probability density functions of the angle of arrival have been validated by
comparing them against the results from real channel measurements data. In addition, the developed three dimensional geometrical scattering
channel model has been extended for multiple input multiple output
wireless channel modeling applications. A three dimensional spatial
correlation function has been developed in terms of some of the physical channel's parameters, such as: displacements and orientation of
the employed antenna elements. The developed correlation function has been used to simulate and investigate the performance
of
wireless multiple input multiple output systems in different scenarios.
Advisors/Committee Members: Buchanan, Doug (Electrical & Computer Eng) Sebak, Abdel (Electrical & Computer Eng) Noghanian, Sima (Electrical and Computer Eng) (supervisor), Alfa, Attahiru (Electrical and Computer Eng) ElMekkawy, Tarek (Mechanical and Manufacturing Eng) Kishk, Ahmed A. (Electrical Engineering, University of Mississippi) (examiningcommittee).
Subjects/Keywords: Electrical Engineering; Wireless Communications; Radio Channel Model
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APA ·
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alsehaili, M. (2011). Generalized Three Dimensional Geometrical Scattering Channel Model for Indoor and Outdoor Propagation Environments. (Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/4384
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):
Alsehaili, Mohammad. “Generalized Three Dimensional Geometrical Scattering Channel Model for Indoor and Outdoor Propagation Environments.” 2011. Thesis, University of Manitoba. Accessed March 04, 2021.
http://hdl.handle.net/1993/4384.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Alsehaili, Mohammad. “Generalized Three Dimensional Geometrical Scattering Channel Model for Indoor and Outdoor Propagation Environments.” 2011. Web. 04 Mar 2021.
Vancouver:
Alsehaili M. Generalized Three Dimensional Geometrical Scattering Channel Model for Indoor and Outdoor Propagation Environments. [Internet] [Thesis]. University of Manitoba; 2011. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/1993/4384.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Alsehaili M. Generalized Three Dimensional Geometrical Scattering Channel Model for Indoor and Outdoor Propagation Environments. [Thesis]. University of Manitoba; 2011. Available from: http://hdl.handle.net/1993/4384
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
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Open Access Theses and Dissertations