Secondary Outage Analysis of Amplify-and-Forward Cognitive Relays with Direct Link and Primary Interference

TL;DR

This paper analyzes the outage probability of a secondary cognitive relay system with direct link and primary interference, deriving closed-form expressions and validating them through simulations.

Contribution

It provides a novel outage analysis for amplify-and-forward cognitive relays considering primary interference and direct links, with closed-form solutions.

Findings

Derived closed-form outage probability expressions.

Accounted for primary interference effects.

Validated analysis with simulation results.

Abstract

The use of cognitive relays is an emerging and promising solution to overcome the problem of spectrum underutilization while achieving the spatial diversity. In this paper, we perform an outage analysis of the secondary system with amplify-and-forward relays in a spectrum sharing scenario, where a secondary transmitter communicates with a secondary destination over a direct link as well as the best relay. Specifically, under the peak power constraint, we derive a closed-form expression of the secondary outage probability provided that the primary outage probability remains below a predefined value. We also take into account the effect of primary interference on the secondary outage performance. Finally, we validate the analysis by simulation results.