Jelena A. Anastasov

Fading and Interference Mitigation in Wireless Communications

The rapid advancement of various wireless communication system services has created the need to analyze the possibility of their performance improvement. Introducing the basic principles of digital communications performance analysis and its mathematical formalization, Fading and Interference Mitigation in Wireless Communications will help you stay up to date with recent developments in the performance analysis of space diversity reception over fading channels in the presence of cochannel interference.The book presents a unified method for computing the performance of digital communication systems characterized by a variety of modulation and detection types and channel models. Explaining the necessary concepts of digital communication system design, the book guides you step by step through the basics of performance analysis of digital communication receivers.Supplying you with the tools to perform an accurate performance evaluation of the proposed communication scenarios, the book includes coverage of multichannel reception in various fading environments, influence of cochannel interference, and macrodiversity reception when channels are simultaneously affected by various types of fading and shadowing. It also includes many numerical illustrations of applications that correspond to practical systems.The book presents a large collection of system performance curves to help researchers and system designers perform their own tradeoff studies. The presented collection of system performances will help you perform trade-off studies among the various communication type/drawback combinations in order to determine the optimal choice considering the available constraints.The concepts covered in this book can be useful across a range of applications, including wireless, satellite, terrestrial, and maritime communications.

Second-order statistics of selection macro-diversity system operating over Gamma shadowed κ-μ fading channels

In this article, infinite-series expressions for the second-order statistical measures of a macro-diversity structure operating over the Gamma shadowed κ-μ fading channels are provided. We have focused on MRC (maximal ratio combining) combining at each base station (micro-diversity), and selection combining (SC), based on output signal power values, between base stations (macro-diversity). Some numerical results of the systems level crossing rate and average fading duration are presented, in order to examine the influence of various parameters such as shadowing and fading severity and number of the diversity branches at the micro-combiners on concerned quantities.

Analytical Model for Outage Probability of Interference-Limited Systems over Extended Generalized-K Fading Channels

In this letter, the novel analytical expressions for the probability density function, cumulative distribution function and moment generating function of the signal-to-interference ratio are derived for the interference-limited system operating over the extended generalized-K (EGK) fading channel. Since the EGK distribution can be used for modeling a great variety of fading channels, the new derived formulae have high level of generality and can be used for estimating the effects of interference and different composite fading channel conditions on system performance. The proposed analytical analysis is complemented by various outage performance results and confirmed by simulations.

PERFORMANCE OF DUAL-HOP RELAYING OVER SHADOWED RICEAN FADING CHANNELS

Performance of Dual-Hop Relaying Over Shadowed Ricean Fading Channels In this paper, an analytical approach for evaluating performance of dual-hop cooperative link over shadowed Ricean fading channels is presented. New lower bound expressions for the probability density function (PDF), cumulative distribution function (CDF) and average bit error probability (ABEP) for system with channel state information (CSI) relay are derived. Some numerical results are presented to show behavior of performance gain for the proposed system. Analytical exact and lower bound expression for the outage probability (OP) of CSI assisted relay are obtained and required numerical results are compared.

Performance analysis of selection diversity over exponentially correlated α– µ fading environment

An approach to the performance analysis of multibranch selection combiner (SC) receiver operating over fading channels is presented. High level of generality for the proposed analysis is achieved by considering correlated α– µ fading environment. The effect of correlation is studied by assuming exponential correlation model of the signals in each diversity branch. The whole analysis is observed in the interference-limited fading environments (SIR-based diversity system is assumed). The important performance measures are considered. Closed form of formulae for the output SIRs probability density function and cumulative distribution function are derived. In order to check the accuracy of the complete proposed formulation, some numerical results are presented. Copyright

On the Effects of Correlation on Outage Performance of FSO-Unbalanced Multibranch SC Receiver

In this letter, we study the outage performance of unbalanced multibranch selection combining receiver operating over free-space optical gamma-gamma turbulence link. The analysis is performed in the case when the position of closely placed photodiodes corresponds to the constant correlation model. Novel analytical expressions for the probability density function and cumulative distribution function of receiver signal-to-noise ratio (SNR) are derived in the infinite series form whose convergence is numerically determined. Based on these analytical results, we examine the simultaneous effects of the spatial correlation, diversity order, photodiodes diameter, and turbulence strength on outage performance. The results illustrate that spatial correlation has a strong effect on SNR gain decreasing, especially for the higher values of diversity order.

Outage capacity evaluation of extended generalized-K fading channel in the presence of random blockage

Abstract In this paper, we analyse the outage and ergodic capacity performance of the extended generalized- K fading channel in the presence of possible temporary physical blockage between the source and the destination. Presented outage capacity analysis is general and can be used in analysis of wireless radio frequency or free-space optics systems. We establish the novel relation among significant parameters as outage capacity, probability of outage, probability of blockage, as well as severity and shaping parameters of multipath fading and shadowing. The theoretical results are expressed in terms of special Fox׳s H functions. The work clearly illustrates the usefulness of Fox׳s H and Meijer׳s G functions in analysing wireless communication systems. The analytical expression derived here enables us to determine the maximum error free data transmission rate for fixed value of outage probability under particular channel conditions. Using expressions for ergodic capacity previously reported in literature, we briefly analyse the impact of blockage on ergodic capacity, too. The numerical results show that the shadowing shaping factor has the considerable effect on outage capacity and is pronounced more extensively when probability of outage is lower. In addition, the results show that the effect of shadowing shaping factor is stronger for outage than ergodic capacity. The effect of multipath fading severity on outage capacity is stronger for lower values of shadowing spread. The link blockage causes significant decreasing of ergodic capacity and appearance of outage floor.

Performance of Dual Branch SSC Receiver in Correlated α-μ Fading Channels

In this paper, the performance analysis of dual branch switch and stay combining (SSC) receivers operating over correlated and identically distributed (i.d.) α-μ fading channels is presented. Assuming this diversity technique, infinite series expressions with fast converging properties are derived for the probability density function (pdf), cumulative distribution function (cdf) and the moments of the output envelope. The proposed analysis is used for evaluating the important performance criteria, such as the outage probability, the mean square output envelope, the amount of fading and the average bit error probability (ABEP). The effects of fading severity, branch correlation and optimum choice of switching threshold are considered and numerically presented. Monte Carlo simulations confirm the validity and accuracy of the derived analytical expressions.

Channel Capacity Analysis Under Various Adaptation Policies and Diversity Techniques over Fading Channels

The lack of available spectrum for expansion of wireless services requires more spectrally efficient communication in order to meet the consumer demand. Since the demand for wireless communication services have been growing in recent years at a rapid pace, conserving, sharing and using bandwidth efficiently is of primary concern in future wireless communications systems. Therefore, channel capacity is one of the most important concerns in the design of wireless systems, as it determines the maximum attainable throughput of the system [1]. It can be defined as the average transmitted data rate per unit bandwidth, for a specified average transmit power, and specified level of received outage or bit-error rate [2]. Skilful combination of bandwidth efficient coding and modulation schemes can be used to achieve higher channel capacities per unit bandwidth. However, mobile radio links are, due to the combination of randomly delayed reflected, scattered, and diffracted signal components, subjected to severe multipath fading, which leads to serious degradation in the link signal-to-noise ratio (SNR). An effective scheme that can be used to overcome fading influence is adaptive transmission. The performance of adaptation schemes is further improved by combining them with space diversity, since diversity combining is a powerful technique that can be used to combat fading in wireless systems resulting in improving link performance [3].

Analysis of SIR-based Triple SC System over Correlated Alpha-Mu Fading Channels

In this paper the performance analysis of signal-to-interference ratio (SIR) based Selection Combining (SC) diversity system over α-μ fading distributed and correlated channels is presented. Formulae for the output SIR’s probability density function (pdf) and cumulative distribution function (cdf) are derived. Also, the results presented in the paper include all important scenarios of triple SC diversity systems, which is main contribution of this paper. Analytical and numerical results are obtained for triple SC pointing out the effects of fading severity and correlation on the system performances.