Performance analysis of fixed-gain AF dual-hop relaying systems over Nakagami-m fading channels in the presence of interference

Abstract

This article presents an analytical investigation on the performance of interference-limited fixed-gain amplify-andforward dual-hop relaying systems over Nakagami-m fading channels. Assuming the fading parameter m of the two hop channels being integer, we derive a closed-form expression of the cumulative distribution function of a new type of random variables involving a number of independent gamma random variables, based on which, the outage performance and symbol error rate of the system are examined, and two important performance metrics at the high signal-to-noise ratio regime, namely, diversity order and coding gain, are characterized. Moreover, expressions of the general moments of the end-to-end signal-to-interference-and-noise ratio are derived and then applied in the analysis of the ergodic capacity of the system. In addition, the impact of interference power distribution on the ergodic capacity of the system is studied with the aid of a majorization result. Our findings suggest that the diversity of the system is limited by the hop experiencing severer fading, and co-channel interferences do not reduce the diversity order of the system, instead, they degrade the outage performance by affecting the coding gain of the system.

Exact Outage Probability of Opportunistic DF Relay Systems With Interference at Both the Relay and the Destination Over Nakagami-$m$ Fading Channels

“…by replacing l with s and d with k, and the pdf of Z 1 is similar to that found in (14) by replacing i d with i k and d with k. Now, using the integral in (19) and with replacing Y by Y 1 and Z by Z 1 , and after some algebraic manipulations, the cdf of γ s,k can be evaluated as (9). Having P r [γ d < u|C L ] and P r [C L ] evaluated, the outage probability in (7) can be calculated.…”

“…Particularly, in [7], Al-Qahtani et al derived closed-form expressions for the outage and symbol error rate of a dual-hop AF relay system over Nakagami-m fading channels, in addition to studying the system behavior at the high-SNR regime. The interference effect at the destination node over Rayleigh and Nakagami-m fading channels was studied in [8] and [9], respectively. Recently, several papers have studied the interference impact at both the relay and the destination [10], [11].…”

Performance analysis of amplify-and-forward relay system with interference-limited destination in different fading environments

“…The impact of interference at the destination node has been presented in [9] and [10], respectively. In [9], the authors evaluated closed-form expressions for both the outage and asymptotic outage probability of fixed-gain AF and DF relay systems in Rayleigh fading environment.…”

“…A key result of this study is that the worst behavior happens when the interference power is equally distributed between the interferers. In [10], exact expressions for both the outage and asymptotic outage probability and the SER have been derived with all links assumed to follow Nakagami-m distribution. The impact of interference at both the relay and the destination has been studied in [11] and [12], respectively.…”

Exact outage probability of opportunistic DF relay systems with interference at both the relay and the destination over Nakagami-m fading channels

“…The interference effect at the destination node has been studied in [8], [9]. In [8], the authors evaluated closed-form expressions for both the outage and asymptotic outage proba bility of a fixed-gain AF and a DF relay systems over Rayleigh fading channels.…”