Channel Estimation and Equalization for Transmitted-Reference Ultra-Wideband Systems
Author: 華文聖
Publisher:
Published: 2008
Total Pages: 68
ISBN-13:
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Author: 華文聖
Publisher:
Published: 2008
Total Pages: 68
ISBN-13:
DOWNLOAD EBOOKAuthor: Xiaofan Yang
Publisher:
Published: 2005
Total Pages: 94
ISBN-13:
DOWNLOAD EBOOKIn this thesis we consider the design of an ultra-wideband (UWB) receiver. We investigate channel estimation and equalization algorithms of ultra-wideband radio with pulse position modulation. We propose a completely blind channel estimation method based on the first-order cyclostationarity in the received signal. In contrast to other blind UWB channel estimation methods, our algorithm exhibits low complexity and is robust for channels with large numbers of taps. We investigate equalization by introducing a discrete-time equivalent model for time-hopping pulse-position-modulated UWB systems. This equivalent model views the transmitter-channel-receiver system at symbol rate. The computational complexity is reduced by processing the received data at symbol rate instead of chip rate. Symbol detection techniques including decision feedback equalization and maximum likelihood detection are evaluated and compared with correlation detection. Chapter 1 is an introduction to UWB systems, including the development of the technology, current research topics, and recent applications. Chapters 2 and 3 study the channel estimation and equalization problems, respectively. Chapter 4 summarizes the thesis and presents possible future work.
Author: Faranak Nekoogar
Publisher:
Published: 2005
Total Pages: 464
ISBN-13:
DOWNLOAD EBOOKAuthor: Solomon Nunoo
Publisher:
Published: 2015
Total Pages: 157
ISBN-13:
DOWNLOAD EBOOKAuthor: Ben Allen
Publisher: John Wiley & Sons
Published: 2006-11-02
Total Pages: 508
ISBN-13: 0470056827
DOWNLOAD EBOOKProviding up-to-date material for UWB antennas and propagation as used in a wide variety of applications, "Ultra-wideband Antennas and Propagation for Communications, Radar and Imaging" includes fundamental theory, practical design information and extensive discussion of UWB applications from biomedical imaging, through to radar and wireless communications. An in-depth treatment of ultra-wideband signals in practical environments is given, including interference, coexistence and diversity considerations. The text includes antennas and propagation in biological media in addition to more conventional environments. The topics covered are approached with the aim of helping practising engineers to view the subject from a different angle, and to consider items as variables that were treated as constants in narrowband and wideband systems. Features tables of propagation data, photographs of antenna systems and graphs of results (e.g. radiation patterns, propagation characteristics) Covers the fundamentals of antennas and propagation, as well as offering an in-depth treatment of antenna elements and arrays for UWB systems, and UWB propagation models Provides a description of the underlying concepts for the design of antennas and arrays for conventional as well as ultra-wideband systems Draws together UWB theory by using case-studies to show applications of antennas and propagation in communication, radar and imaging systems The book highlights the unique design issues of using ultra-wideband and will serve both as an introductory text and a reference guide for designers and students alike.
Author: Maise Tamouh Al Atassi
Publisher:
Published: 2011
Total Pages: 100
ISBN-13:
DOWNLOAD EBOOKDue to the desirable characteristics of Ultra Wideband (UWB) signals, modern-day wireless communications systems are becoming increasingly designed to use such signals. However, UWB technology faces many challenges such as the extremely high sampling rate, the large channel length and the complicated receiver design. These challenges call for adopting a new technique that overcomes the demanding Shannon-Nyquist approach for sampling and allows for signal reconstructions using a fewer number of measurements, such as Compressed Sensing (CS). In this thesis, the theory of CS is employed as part of the UWB channel estimation process using greedy algorithms. We study the performance of a variety of greedy reconstruction algorithms including "Matching Pursuit" and "Weighted Matching Pursuit", under different types of measurement matrices while taking into consideration the effect of additive noise on the performance of the system. We propose two novel greedy reconstruction algorithms: "Block-wise Matching Pursuit" and "Bayesian Weighted Matching Pursuit", and prove that they outperform existing reconstruction algorithms in terms of execution time and power consumption.
Author: Mohammad Abdul Matin
Publisher: IntechOpen
Published: 2012-10-03
Total Pages: 372
ISBN-13: 9789535107811
DOWNLOAD EBOOKUltra wideband (UWB) has advanced and merged as a technology, and many more people are aware of the potential for this exciting technology. The current UWB field is changing rapidly with new techniques and ideas where several issues are involved in developing the systems. Among UWB system design, the UWB RF transceiver and UWB antenna are the key components. Recently, a considerable amount of researches has been devoted to the development of the UWB RF transceiver and antenna for its enabling high data transmission rates and low power consumption. Our book attempts to present current and emerging trends in-research and development of UWB systems as well as future expectations.
Author: Witty Wong
Publisher:
Published: 2004
Total Pages: 154
ISBN-13:
DOWNLOAD EBOOKAuthor: Ke-Lin Du
Publisher: Cambridge University Press
Published: 2010-04-15
Total Pages: 1020
ISBN-13: 1139485768
DOWNLOAD EBOOKThis practically-oriented, all-inclusive guide covers all the major enabling techniques for current and next-generation cellular communications and wireless networking systems. Technologies covered include CDMA, OFDM, UWB, turbo and LDPC coding, smart antennas, wireless ad hoc and sensor networks, MIMO, and cognitive radios, providing readers with everything they need to master wireless systems design in a single volume. Uniquely, a detailed introduction to the properties, design, and selection of RF subsystems and antennas is provided, giving readers a clear overview of the whole wireless system. It is also the first textbook to include a complete introduction to speech coders and video coders used in wireless systems. Richly illustrated with over 400 figures, and with a unique emphasis on practical and state-of-the-art techniques in system design, rather than on the mathematical foundations, this book is ideal for graduate students and researchers in wireless communications, as well as for wireless and telecom engineers.
Author: Maryam Vala
Publisher:
Published: 2014
Total Pages:
ISBN-13:
DOWNLOAD EBOOK"Ultra Wideband (UWB) is a rapidly growing technology for digital wireless communications. UWB utilizes low power, ultra short, pulses and is specifically suited for short-range, high-rate indoor wireless communications as well as fine localization applications. The attractive properties of UWB are a direct consequence of its very wide bandwidth that also implies an extremely high Nyquist sampling rate, so digital processing of UWB signals requires the use of fast and efficient, and therefore, expensive, Analog to Digital Converters. UWB systems are commonly used in indoor environments in which propagation is characterized by long but sparse multipath channels. Multi-path channels cause inter symbol interference (ISI) and introduce distortion to the received signal. To counter the effects of the channel, the channel impulse response must be accurately estimated at the receiver. There are two main estimation approaches for UWB channels: Compressed Sensing (CS)-based and Adaptive Filter (AF)-based. The former combine sampling and compression into a single linear measurement process that operates at sub-Nyquist rate by capitalizingon the sparsity of UWB signals. The latter, uses Least-Mean-Square filtering principles to obtain low complexity channel estimation methods. The problem we consider in this thesisis the estimation of a long sparse multi-path channel in an UWB system. We focus on systems that use Pulse Position Modulation (PPM) that is one of the most commonly used modulation schemes in UWB systems. We review CS and AF based methods and then we propose new AF-type methods specifically for the estimation of sparse multi-path channels with PPM inputs. The main idea behind the proposed methods is to estimate the long channel in sections in order to reduce the computational cost and improve the estimation performance. Finally, we present simulation results showing the superior performance of the proposed algorithms." --