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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Impulsive radio propagation and time reversed MIMO system for UWB wireless communications : a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /

Zhou, Chenming (Jim), January 2008 (has links)
Thesis (Ph.D.)--Tennessee Technological University, 2008. / Includes bibliographical references.
12

Ultra-Wideband receiver implementation using analog correlators /

Harbert, Kyle January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaf 56). Also available on the World Wide Web.
13

Adaptive, wideband analog-to-digital conversion for convergent communication systems /

Batten, Robert D., January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 80-84). Also available on the World Wide Web.
14

Implementation of an ultra-wideband transceiver for sensor applications /

Jann, Benjamin J. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 49-50). Also available on the World Wide Web.
15

Interference cancellation in impulse radio

Wang, Xufang. January 2005 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
16

Understanding the ultra-wideband channel within a computer chassis /

Redfield, Stephen J. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 71-76). Also available on the World Wide Web.
17

Robust, low complexity and energy efficient baseband receiver design for MB-OFDM UWB. / CUHK electronic theses & dissertations collection

January 2011 (has links)
Architectures of matched filter in packet detector, CFO corrector, FFT output reorder buffer and phase tracking block are optimized for low complexity. Implemented in O.13-mum CMOS technology, the proposed baseband receiver system has the core area of 2.5 mm2 and the estimated power consumption is 170 mW, which is equivalent to the energy efficiency of 88 pJ/b at 480 Mbps data rate. The implementation results verify the robustness, low complexity and power efficiency of the proposed MB-OFDM UWB baseband receiver. / As an OFDM-based system, MB-OFDM UWB is vulnerable and sensitive to carrier frequency offset (CFO). We employ multipartite table method (MTM) to implement arctangent and sin/cos functions for frequency synchronization. Compared with traditional algorithms, MTM has the advantages of low cost, low power consumption and higher processing speed. Residual phase distortion is corrected by a highly simplified phase tracking method, which also has better performance compared with traditional phase tracking scheme. / Synchronization plays the key role for the performance of the whole baseband receiver system. In this dissertation, a dual-threshold (DT) packet detection scheme is proposed for timing synchronization. Compared with traditional cross-correlation algorithm, DT has much better detection performance, especially in high noise environment. / Ultra-wideband (UWB) technology, targeting at wireless personal area networks (WPANs),brings the convenience of high-speed and short-range wireless interconnects. As a novel communication technique, multi-band orthogonal frequency division multiplexing (MB-OFDM) UWB has the features of high spectrum efficiency, multiple access capability and robustness against narrow band interference. However, its inherent high complexity and the requirement of powerful processing for good performance are the obstacles for practical application. / Fan, Wen. / Adviser: Choy Chiu-Sing. / Source: Dissertation Abstracts International, Volume: 73-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 105-112). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
18

Modeling and analysis of ultra wideband systems. / CUHK electronic theses & dissertations collection

January 2005 (has links)
Finally, we extend the threshold optimization algorithm to solve a more general N-state distributed estimation problem. We combine multiple observations of a signal process via the maximum function for decision-making and find out that the optimal decision function can be implemented by means of thresholds under suitable technical conditions. We propose here a training sequence based algorithm for threshold adjustment. The algorithm is a variation of the Kiefer-Wolfowitz algorithm with expending truncations and randomized differences. Convergence of this algorithm is also established. / Prior to timing jitter robust receiver design, a measurement campaign was carried out on indoor UWB signal propagation in order to characterize the UWB indoor channel and provide a simulation platform. Channel parameters are analyzed based on measurement data, including path loss, RMS delay spread, amplitude distribution and correlation properties. / Ultra-wideband (UWB) technique has been the subject of extensive research in recent years due to its unique capabilities and potential applications, particularly in short-range multiple access wireless communications. Despite of many advantages over traditional narrow band systems, UWB impulse radio is sensitive to timing jitter effect. In this thesis, we devote to design a high speed UWB receiver which is robust under timing jitter. The basic idea is that the received signal is over-sampled within the sampling window and its maximum value or maximum absolute value is selected as the decision variable and to be compared with a threshold. A main advantage of this scheme is that its performance will not degrade if the timing jitter is shorter than half of the window length. Therefore, the proposed scheme is robust against timing jitter and no precise synchronization between the transmitter and receiver is required. However, how to determine the optimal threshold value is a critical issue for this new scheme. In this thesis, we propose a simple stochastic approximation (SA) approach to adjust the threshold recursively. The approach is based on a version of SA known as the Kiefer-Wolfowitz (KW) algorithm with expanding truncations and randomized differences. Corresponding to two different decision-making structures, two SA algorithms are presented and their convergence properties are analyzed, respectively. The proposed algorithms are effective in threshold optimization and the convergence rate is fast, as demonstrated by the numerical results. / Li Qiang. / "June 2005." / Adviser: Wing Shing Wong. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0440. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 133-138). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
19

Antennas for spectrum efficient wireless communications /

Chan, Chiu Lun. January 2003 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 68-72). Also available in electronic version. Access restricted to campus users.
20

Ultra-wideband systems exploiting orthonormal waveforms

Kim, Youngok, 1971- 12 August 2011 (has links)
Not available / text

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