Download or read book Analytical Evaluation of Adaptive Transmission Protocols for Markov Models of Channels with Fading and Moderate Shadowing written by Sneha L. Kottapalli and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Adaptive transmission protocols are often employed to communicate over wireless channels with fading and other time-varying propagation losses. The protocols compensate for the propagation losses and maintain high throughput by adjusting transmission parameters in response to the channel variations. Performance evaluations for practical adaptive transmission protocols typically require simulation of both the time-varying processes and the procedure by which the protocol derives information about the channel quality. In this thesis, we develop an analytical method to evaluate the performance of two practical protocols, an adaptive coding protocol and an adaptive modulation and coding protocol, which rely on statistics derived from the demodulation process. Our method for performance analysis avoids the need for simulations of the adaptive protocols and the derivation of statistics that are used for adaptation; furthermore, our approach avoids the simulation of the time-varying channel.

Download or read book Channel Adaptive Transmission of Big Data written by Wen-Jing Wang and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We investigate the statistics of transmission time of wireless systems employing adaptive transmission. Unlike traditional transmission systems where the transmission time of a fixed amount of data is typically regarded as a constant, the transmission time with adaptive transmission systems becomes a random variable, as the transmission rate varies with the fading channel condition. To facilitate the design and optimization of wireless transmission schemes, we present an analytical framework to determine statistical characterizations for the transmission time with adaptive transmission. In particular, we derive the exact statistics of transmission time over block fading channels. The probability mass function (PMF) and cumulative distribution function (CDF) of transmission time are obtained for both slow and fast fading scenarios. We further extend our analysis to Markov channels, where the transmission time becomes a sequence of exponentially distributed random-length time slots. Analytical expression for the probability density function (PDF) of transmission time is derived for both fast and slow fading scenarios. Since the energy consumption can be characterized by the product of power consumption and transmission time, we also evaluate the energy consumption for wireless systems with adaptive transmission. Cognitive radio communication can opportunistically access underutilized spectrum for emerging wireless applications. With interweave cognitive implementation, a secondary user (SU) transmits only if a primary user does not occupy the channel and waits for transmission otherwise. Therefore, secondary packet transmission involves both transmission and waiting periods. The resulting extended delivery time (EDT) is critical to the throughput analysis of secondary system. With the statistical results of transmission time, we derive the PDF of EDT considering random-length SU transmission and waiting periods for continuous spectrum sensing and semi-periodic spectrum sensing. Taking spectrum sensing errors into account, we propose a discrete Markov chain modeling slotted secondary transmission coupled with periodic spectrum sensing. Markov modeling is applied to energy efficiency optimization and queuing performance evaluation.

Download or read book Mobile Fading Channels written by Matthias Pätzold and published by Wiley-Blackwell. This book was released on 2002-04 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mobile channel fading is a loss in transmission intensity caused by changes in the transmission medium. By dealing with the modelling, analysis and simulation of mobile fading channels this text provides a fundamental understanding of many issues in the area of mobile fading channel modelling.; The main topics addressed in the volume are: fundamentals of stochastic and deterministic channel models and modelling and simulation of frequency-nonselective and frequency-selective fading channels. The guide also features methods for the design and realization of efficient channel simulators and fast channel simulators and MATLAB-programs for the evaluation and simulation of mobile fading channels.

Download or read book Adaptive Transmission Techniques for Fading Channels written by David M. Zook and published by . This book was released on 2003 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Observationes binae anatomicae de quatuor et quinque ramis ex arcu arteri magn adscendentibus written by and published by . This book was released on 1744 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling and Performance Evaluation of Multipath Fading Channels by Hidden Markov Model written by Otto Hing-Bill Lee and published by . This book was released on 1995 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Service Outage Based Adaptive Transmission in Fading Channels written by Jianghong Luo and published by . This book was released on 2004 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Analysis of Optimal Training for Correlated Fading Channels Using Cutoff Rate written by and published by . This book was released on 2004 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: We consider the problem of optimal allocation of resources (power and bandwidth) between training and data for transmission over a Gauss Markov fading channel. Inaccurate channel state information ((CSI) is available at the receiver through periodic training. The transmitter is assumed to have knowledge of the channel Doppler spread. We compute the ergodic cutoff rate Ro for the temporally-correlated Rayleigh flat fading channels with imperfect channel state information (CSI) available at the receiver. We study MMSE estimators that predict the current channel state based on: all past pilot observations, only the most recent pilot observation, and the most recent and next in the future pilot observations.

Download or read book On the Achievable Rate of Stationary Fading Channels written by Meik Dörpinghaus and published by Springer. This book was released on 2013-07-15 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book On Signal Transmission and Detection Over Fading Channels written by Fadel Fadel Abdel-Aziz Digham and published by . This book was released on 2005 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Analysis of Optimal Training for Correlated Fading Channels Using Cutoff Rate written by Saswat Misra and published by . This book was released on 2004-04 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: We consider the problem of optimal allocation of resources (power and bandwidth) between training and data for transmission over a Gauss Markov fading channel. Inaccurate channel state information ((CSI) is available at the receiver through periodic training. The transmitter is assumed to have knowledge of the channel Doppler spread. We compute the ergodic cutoff rate Ro for the temporally-correlated Rayleigh flat fading channels with imperfect channel state information (CSI) available at the receiver. We study MMSE estimators that predict the current channel state based on: all past pilot observations, only the most recent pilot observation, and the most recent and next in the future pilot observations.

Download or read book Channel Access Protocols Based on Transmission Groups written by Andrew Muir and published by . This book was released on 1998 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Study of ARQ type Strategies and Adaptive Modulation for Transmission on Fading Channels written by Kenneth Chee Kum Cheong and published by . This book was released on 2000 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2004 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theses on any subject submitted by the academic libraries in the UK and Ireland.

Download or read book Proceedings written by and published by . This book was released on 2001 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Knowledge Based Fading Channel Analyzer for Adaptive Radio Links written by Jeffrey S. Yalowitz and published by . This book was released on 1990 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new analysis technique proposed for fading radio channels combines object-oriented, knowledge-based processing algorithms with conventional quantitative methods to provide on-line estimates of channel dynamics and permits real-time formulation of adaptive link control strategies. Temporal features of a digitized signal envelope power record from the receiver are classified by statistical properties and threshold crossing behavior into elemental descriptive objects (e.g., increasing signal, decreasing signal), which have both symbolic and parametric attributes. An expert-system inference engine operates on the elemental objects to construct more complex descriptive objects that characterize complete signal fade waveforms and fading sequences. Techniques are being developed to appress additional rules and statistical system identification procedures to generate multipath propagation models can be used to derivation of adaptive equalization and link control directives. The proposed technique integrates use of automated heuristic procedures and adaptive signal processing to permit effective interpretation of channel conditions in cases where time and information are limited. Applications of knowledge-based ionospheric propagation analysis include adaptive HF communications links, ionospheric monitoring, and over-the-horizon radar.

Download or read book Proceedings Exhibition future Access written by and published by . This book was released on 1997 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: