On the Achievable Rate of Stationary Fading Channels
On the Achievable Rate of Stationary Fading Channels

Author: Meik Dörpinghaus

Publisher: Springer Science & Business Media

Published: 2011-08-14

Total Pages: 317

ISBN-13: 3642197809

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This volumes discusses various aspects regarding the capacity/achievable data rate of stationary Rayleigh fading channels. First, it analyses bounds on the achievable data rate with zero-mean proper Gaussian input symbols, which are capacity achieving in the coherent case, i.e., in case of perfect channel knowledge at the receiver. These bounds are tight in the sense that the difference between the upper and the lower bound is bounded for all SNRs. The lower bound converges to the coherent capacity for asymptotically small channel dynamics. Furthermore, these bounds are extended to the case of multiple-input multiple-output (MIMO) channels and to the case of frequency selective channels. In a further part, the present work studies the achievable rate with receivers based on synchronized detection and a code-aided channel estimation. For a specific type of such a receiver an approximate upper bound on the achievable rate is derived. The comparison of this approximate upper bound and the achievable data rate with receivers using synchronized detection based on a solely pilot based channel estimation gives an approximate upper bound on the possible gain by using this kind of code-aided channel estimation in comparison to the conventional receiver using a solely pilot based channel estimation. In addition, the achievable data rate with an optimal joint processing of pilot and data symbols is studied and a lower bound on the achievable rate for this case is derived. In this context, it is also shown which part of the mutual information of the transmitter and the receiver is discarded when using the conventional receiver with synchronized detection based on a solely pilot based channel estimation.

Deterministic Modeling and Long Range Prediction of Fast Fading Channels with Applications to Mobile Radio Systems
Deterministic Modeling and Long Range Prediction of Fast Fading Channels with Applications to Mobile Radio Systems

Author:

Publisher:

Published: 2001

Total Pages:

ISBN-13:

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In wireless communication systems, the direct signal and the reflected signals form an interference pattern resulting in a received signal given by the sum of these components. They are distinguished by their Doppler shifts at the mobile. Since the parameters associated with these components are slowly varying, the fading coefficients can be accurately predicted far ahead. We introduced a novel algorithm for long range prediction of fading channels. This algorithm finds the linear Minimum MeanSquared Error (MMSE) estimate of the future fading coefficients given a fixed number of previous observations. We show that thesuperior performance of this algorithm is due to its longer memoryspan achieved by using lower sampling rate given fixed model orderrelative to the conventional (data rate) methods of fading prediction. This long range prediction capability for fading channels would provide enabling technology for accurate power control, reliable transmitter and/or receiver diversity, more effective adaptive modulation and coding and improvements in many other components ofwireless systems. In this thesis, we demonstrate that largeimprovements in the performance are possible for both flat and frequency-selective rapidly varying fading channels when the proposed prediction method is used. We illustrate the performance enhancements both at the transmitter and the receiver with both theoretical and simulation results.

A Study of Rayleigh Fading Channel Models
A Study of Rayleigh Fading Channel Models

Author: Mahdin Mahboob

Publisher: LAP Lambert Academic Publishing

Published: 2011-07

Total Pages: 72

ISBN-13: 9783845411668

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These days, computer simulation is increasingly being used for design and performance evaluation of communication systems. When simulating a mobile wireless channel for such systems, it is usually assumed that the fading process is a random variate with Rayleigh distribution. In this paper, we have tried to understand Rayleigh Fading (which best describes the scenario inan urban or macrocell environment) better by comparing different models and observing the changes that are caused by varying different parameters. At present, there are a number of methods to generate the Rayleigh fadingprocess, some of them quite recently proposed. Due to the use of different Rayleigh fading generators, different simulations of the same communication system yield different results. Two methods, viz., the Jakes method and the Dent(Modified Jakes) method have been studied, simulated and compared based on the Rayleigh fading process properties. Various communication systems have been simulated using the Rayleigh fading generators and the differences in theresults, if any, have been analyzed. It was seen that the Dent method is usually seen to better describe a Rayleigh fading process.

Wireless Communications
Wireless Communications

Author: Andreas F. Molisch

Publisher: John Wiley & Sons

Published: 2012-02-06

Total Pages: 883

ISBN-13: 1118355687

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"Professor Andreas F. Molisch, renowned researcher and educator, has put together the comprehensive book, Wireless Communications. The second edition, which includes a wealth of new material on important topics, ensures the role of the text as the key resource for every student, researcher, and practitioner in the field." —Professor Moe Win, MIT, USA Wireless communications has grown rapidly over the past decade from a niche market into one of the most important, fast moving industries. Fully updated to incorporate the latest research and developments, Wireless Communications, Second Edition provides an authoritative overview of the principles and applications of mobile communication technology. The author provides an in-depth analysis of current treatment of the area, addressing both the traditional elements, such as Rayleigh fading, BER in flat fading channels, and equalisation, and more recently emerging topics such as multi-user detection in CDMA systems, MIMO systems, and cognitive radio. The dominant wireless standards; including cellular, cordless and wireless LANs; are discussed. Topics featured include: wireless propagation channels, transceivers and signal processing, multiple access and advanced transceiver schemes, and standardised wireless systems. Combines mathematical descriptions with intuitive explanations of the physical facts, enabling readers to acquire a deep understanding of the subject. Includes new chapters on cognitive radio, cooperative communications and relaying, video coding, 3GPP Long Term Evolution, and WiMax; plus significant new sections on multi-user MIMO, 802.11n, and information theory. Companion website featuring: supplementary material on 'DECT', solutions manual and presentation slides for instructors, appendices, list of abbreviations and other useful resources.