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- Title
- A cooperative ad hoc network to support efficient access to Internet data
- Creator
- Kang, Seung-Seok
- Date
- 2004
- Collection
- Electronic Theses & Dissertations
- Title
- A framework for handling user mobility in wireless ATM networks
- Creator
- Lin, Hui-Tang
- Date
- 1998
- Collection
- Electronic Theses & Dissertations
- Title
- A network feedback architecture for self adaptive applications in wireless networks
- Creator
- Singh, Nagendra S.
- Date
- 2004
- Collection
- Electronic Theses & Dissertations
- Title
- A wirelessly controlled magnetic force actuator and its AFM measurements
- Creator
- Abu-Nimeh, Faisal T.
- Date
- 2007
- Collection
- Electronic Theses & Dissertations
- Title
- Adapting wireless sensor networks to obstructed and concave environments
- Creator
- Wang, Chen
- Date
- 2007
- Collection
- Electronic Theses & Dissertations
- Title
- Adaptive SCTP for improved performance in mobile ad-hoc networks
- Creator
- Pongaliur, Kanthakumar Mylsamy
- Date
- 2005
- Collection
- Electronic Theses & Dissertations
- Title
- Adaptive wireless video using channel state information
- Creator
- Cho, Yongju
- Date
- 2008
- Collection
- Electronic Theses & Dissertations
- Title
- Advanced approaches in information transmission and access control for wireless communication networks
- Creator
- Wang, Huahui
- Date
- 2006
- Collection
- Electronic Theses & Dissertations
- Title
- Advanced receivers for WCDMA downlink
- Creator
- Desai, Keyur
- Date
- 2004
- Collection
- Electronic Theses & Dissertations
- Title
- An integrated approach to autonomous computation in data streaming applications
- Creator
- Kasten, Eric P.
- Date
- 2007
- Collection
- Electronic Theses & Dissertations
- Title
- Analysis and design of reliable and stable link-layer protocols for wireless communication
- Creator
- Soltani, Sohraab
- Date
- 2009
- Collection
- Electronic Theses & Dissertations
- Title
- BTAudio (Bluetooth Audio Program) and quite talk profile
- Creator
- Chen, Jun
- Date
- 2003
- Collection
- Electronic Theses & Dissertations
- Title
- Building a location-based prioritized overlay multicast in ad-hoc environments
- Creator
- Liu, Yunhao
- Date
- 2003
- Collection
- Electronic Theses & Dissertations
- Title
- CMOS variable gain amplifier (VGA) for application in RF front end of a satellite tv tuner
- Creator
- Rosik, Nick Joel
- Date
- 2004
- Collection
- Electronic Theses & Dissertations
- Title
- Coding over resource-constrained wireless networks
- Creator
- Halloush, Rami D.
- Date
- 2012
- Collection
- Electronic Theses & Dissertations
- Description
-
In practice, wireless networks operate under multiple, mostly severe, constraints (bandwidth, energy resources, etc). Consequently, efficient techniques have to be employed in communicating data with sufficiently high data rates (depending on the application) while complying with the imposed constraints. Distributed Video Coding (DVC) and Network Coding (NC) are amongst the most dominant techniques employed in constrained data networks. In this dissertation, we address these two techniques...
Show moreIn practice, wireless networks operate under multiple, mostly severe, constraints (bandwidth, energy resources, etc). Consequently, efficient techniques have to be employed in communicating data with sufficiently high data rates (depending on the application) while complying with the imposed constraints. Distributed Video Coding (DVC) and Network Coding (NC) are amongst the most dominant techniques employed in constrained data networks. In this dissertation, we address these two techniques with the objective of realizing practical and efficient data networking solutions that fit in resource constrained wireless networks. In one part of the dissertation we address DVC over Visual Sensor Networks (VSNs) from a practical point of view, i.e., unlike a large body of research work related to this topic where the focus is on theoretical analysis and simulation, we study the practical aspects that arise when deploying DVC over real visual sensors. To that end, we develop a Resource-constrained DVC (RDVC) codec, deploy it over some of the widely used visual sensors, and conduct precise energy measurements that are used throughout our study.One RDVC-related challenge that we address in this dissertation is source rate estimation, i.e., trying to efficiently identify the source rate to be used in encoding a frame. This question is crucial since sending more bits than necessary will lead to inefficiency in compression while sending fewer bits will lead to failure in decoding. We propose a practical solution that completely eliminates the need for the costly feedback messages.Another challenge we address is the global choice between a DVC encoding option that involves intensive computations and leads to less transmission versus another choice with minimal computations that implies higher transmission-energy overhead. We carry out an operational energy-distortion analysis for a variety of options available to RDVC on visual sensors.Polar codes are the first codes proven to achieve capacity while having low encoding and decoding complexity. This motivates us to employ polar codes in our DVC platform. We compare the performance of polar codes with the more established and more investigated Low Density Parity Check Accumulate (LDPCA) codes in the context of DVC. Our results show that polar codes offer a clear advantage when coding smaller size image blocks. Consequently, polar codes could represent a viable solution for distributed sensor networks that capture low-resolution video signals. In the final part of the dissertation, we survey state-of-the-art NC solutions designed to achieve high throughput transmission in multicasting over wireless mesh networks while maintaining 100% packet delivery ratio. We propose HopCaster; a scheme that employs the cache-and-forward transport strategy. We show that HopCaster achieves significant performance gains compared to schemes that employ the end-to-end transport strategy.
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- Title
- Complexity distortion optimization for video over wireless devices
- Creator
- Ray, Alan Paul
- Date
- 2004
- Collection
- Electronic Theses & Dissertations
- Title
- Controlled mobility for performance enhancements in wireless sensor networks
- Creator
- Rao, Jayanthi
- Date
- 2009
- Collection
- Electronic Theses & Dissertations
- Title
- Cooperative content caching for capacity and cost management in mobile ecosystems
- Creator
- Taghi Zadeh Mehrjardi, Mahmoud
- Date
- 2012
- Collection
- Electronic Theses & Dissertations
- Description
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The objective of this thesis is to develop an architectural framework of social community based cooperative caching for minimizing electronic content provisioning cost in Mobile Social Wireless Networks (MSWNET). MSWNETs are formed by wireless mobile devices sharing common interests in electronic content, and physically gathering in public settings such as University campuses, work places, malls, and airports. Cooperative caching in such MSWNETs are shown to be able to reduce content...
Show moreThe objective of this thesis is to develop an architectural framework of social community based cooperative caching for minimizing electronic content provisioning cost in Mobile Social Wireless Networks (MSWNET). MSWNETs are formed by wireless mobile devices sharing common interests in electronic content, and physically gathering in public settings such as University campuses, work places, malls, and airports. Cooperative caching in such MSWNETs are shown to be able to reduce content provisioning cost which heavily depends on service and pricing dependencies among various stakeholders including content providers, network service providers, and end consumers. This thesis develops practical network, service, and economic pricing models which are then used for creating an optimal cooperative caching strategy based on social community abstraction in wireless networks. The developed framework includes optimal caching algorithms, analytical models, simulation, and prototype experiments for evaluating performance of the proposed strategy. The main contributions are: 1) formulation of economic cost-reward flow models among the MSWNET stakeholders, 2) developing optimal distributed cooperative caching algorithms, 3) characterizing the impacts of network, user and object dynamics, 4) investigating the impacts of user non-cooperation, and finally 5) developing a prototype Social Wireless Network for evaluating the impacts of cooperative caching in a Mobile Social Wireless Networks.
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- Title
- Design and evaluation of adaptive software for mobile computing systems
- Creator
- Zhou, Zhinan
- Date
- 2006
- Collection
- Electronic Theses & Dissertations
- Title
- Efficient and secure system design in wireless communications
- Creator
- Song, Tianlong
- Date
- 2016
- Collection
- Electronic Theses & Dissertations
- Description
-
Efficient and secure information transmission lies in the core part of wireless system design and networking. Comparing with its wired counterpart, in wireless communications, the total available spectrum has to be shared by different services. Moreover, wireless transmission is more vulnerable to unauthorized detection, eavesdropping and hostile jamming due to the lack of a protective physical boundary.Today, the two most representative highly efficient communication systems are CDMA (used...
Show moreEfficient and secure information transmission lies in the core part of wireless system design and networking. Comparing with its wired counterpart, in wireless communications, the total available spectrum has to be shared by different services. Moreover, wireless transmission is more vulnerable to unauthorized detection, eavesdropping and hostile jamming due to the lack of a protective physical boundary.Today, the two most representative highly efficient communication systems are CDMA (used in 3G) and OFDM (used in 4G), and OFDM is regarded as the most efficient system. This dissertation will focus on two topics: (1) Explore more spectrally efficient system design based on the 4G OFDM scheme; (2) Investigate robust wireless system design and conduct capacity analysis under different jamming scenarios. The main results are outlined as follows.First, we develop two spectrally efficient OFDM-based multi-carrier transmission schemes: one with message-driven idle subcarriers (MC-MDIS), and the other with message-driven strengthened subcarriers (MC-MDSS). The basic idea in MC-MDIS is to carry part of the information, named carrier bits, through idle subcarrier selection while transmitting the ordinary bits regularly on all the other subcarriers. When the number of subcarriers is much larger than the adopted constellation size, higher spectral and power efficiency can be achieved comparing with OFDM. In MC-MDSS, the idle subcarriers are replaced by strengthened ones, which, unlike idle ones, can carry both carrier bits and ordinary bits. Therefore, MC-MDSS achieves even higher spectral efficiency than MC-MDIS.Second, we consider jamming-resistant OFDM system design under full-band disguised jamming, where the jamming symbols are taken from the same constellation as the information symbols over each subcarrier. It is shown that due to the symmetricity between the authorized signal and jamming, the BER of the traditional OFDM system is lower bounded by a modulation specific constant. We develop an optimal precoding scheme, which minimizes the BER of OFDM systems under full-band disguised jamming. It is shown that the most efficient way to combat full-band disguised jamming is to concentrate the total available power and distribute it uniformly over a particular number of subcarriers instead of the entire spectrum. The precoding scheme is further randomized to reinforce the system jamming resistance.Third, we consider jamming mitigation for CDMA systems under disguised jamming, where the jammer generates a fake signal using the same spreading code, constellation and pulse shaping filter as that of the authorized signal. Again, due to the symmetricity between the authorized signal and jamming, the receiver cannot really distinguish the authorized signal from jamming, leading to complete communication failure. In this research, instead of using conventional scrambling codes, we apply advanced encryption standard (AES) to generate the security-enhanced scrambling codes. Theoretical analysis shows that: the capacity of conventional CDMA systems without secure scrambling under disguised jamming is actually zero, while the capacity can be significantly increased by secure scrambling.Finally, we consider a game between a power-limited authorized user and a power-limited jammer, who operate independently over the same spectrum consisting of multiple bands. The strategic decision-making is modeled as a two-party zero-sum game, where the payoff function is the capacity that can be achieved by the authorized user in presence of the jammer. We first investigate the game under AWGN channels. It is found that: either for the authorized user to maximize its capacity, or for the jammer to minimize the capacity of the authorized user, the best strategy is to distribute the power uniformly over all the available spectrum. Then, we consider fading channels. We characterize the dynamic relationship between the optimal signal power allocation and the optimal jamming power allocation, and propose an efficient two-step water pouring algorithm to calculate them.
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