Performance Analysis of Amplify-and-Forward Systems with Single Relay Selection in Correlated Environments

Abstract

In this paper, we consider amplify-and-forward (AnF) cooperative systems under correlated fading environments. We first present a brief overview of existing works on the effect of channel correlations on the system performance. We then focus on our main contribution which is analyzing the outage probability of a multi-AnF-relay system with the best relay selection (BRS) scheme under a condition that two channels of each relay, source-relay and relay-destination channels, are correlated. Using lower and upper bounds on the end-to-end received signal-to-noise ratio (SNR) at the destination, we derive corresponding upper and lower bounds on the system outage probability. We prove that the system can achieve a diversity order (DO) equal to the number of relays. In addition, and importantly, we show that the considered correlation form has a constructive effect on the system performance. In other words, the larger the correlation coefficient, the better system performance. Our analytic results are corroborated by extensive Monte-Carlo simulations.

Outage Probability Analysis of the Relay Network with Correlated Relaying Channels

“…The relaying channels h l and g l are assumed to be correlated with correlation µ = |µ| • exp(jε). This assumption makes sense especially in the case there is no line-ofsight (LoS) communication between T 1 and T 2 , i.e., relay network of vehicule-to-vehicule (V2V) communications at the crossing streets and/or critical points [4], [8]. We assume that the transmit power at the source T 1 and each relay R l are P t and P r , respectively.…”

“…In practice, because the signals experience common scatterers, the channels can be correlated [6], [7], especially in the cooperative sensor networks, where low-complexity nodes are densely deployed. There are various kinds of channel correlations existing in the relay network and the review of such channel correlations has been thoroughly documented in [8]. The authors then analyzed the impact on the performance of the best-relay-selection-scheme based relay network, when there is a correlation between source-relay and relaydestination channels for each relay.…”

“…In this paper, we investigate the received signal-tonoise ratio (SNR) outage probability of the relay network in the presence of the correlated relaying channels. On the contrary to [8], we assume the system uses all the signals coming from the relay nodes (no relay selection). More specifically, our contributions are summarized as (1) the derivation of the exact probability density function (PDF) of the modulus of sum of products of two correlated Gaussian random variables (RVs), which is useful to characterize the cascaded relaying channels; (2) the derivations of the PDF and cumulative distribution function (CDF) of received SNR; (3) the received SNR outage probability analysis of the relay nework with correlated relaying channels and numerical validations.…”

Pairwise Error Probability Analysis of Dual Hop Relaying Network over Time Selective Nakagami-m Fading Channel with Imperfect CSI and Node Mobility

“…The closed-form expressions for outage channel capacity is obtained using the complementary cumulative distribution function (CCDF) of the end-to-end signal to noise ratio (SNR). In [6], the authors investigated the AF relaying protocol over correlated Rayleigh fading channel conditions. In this work outage probability (OP) of best relay selection (BRS) based AF wireless system is investigated considering correlated source to destination (SD), source to relay (SR) and relay to destination (RD) fading links.…”

“…A low-complexity piecewise linear decoder is derived for arbitrary complex-valued constellations, which performs like maximum likelihood decoder for all SNR values. However, AF relaying suffers from noise amplification and fixed DF fears performance degradation in case of improper decoding at relay as described in [3][4][5][6][7]. To overcome this problem S-DF relaying protocol is used in which if the SNR of a signal received at the relay exceeds a certain threshold then the relay decodes the received signal and forwards the decoded information to the destination.…”