Outage Probability and Power Allocation for Amplify-and-Forward Cooperative Relaying Systems with Correlated Shadowing

In this paper, we investigate the effect of shadowing on optimal power allocation of amplify- and-forward cooperative relaying systems. Considering the joint effects of path loss, correlated shadowing and flat Rayleigh fading, the approximate outage probability at high signal-to- noise ratio (SNR) is first derived. Then we solve the power allocation problem by minimizing the approximate outage probability subject to a total power constraint. It is shown by the analytical results that the correlation coefficients and the standard deviations of shadowing have a significant impact on the optimal power allocation. The simulation results show that the proposed power allocation scheme yields about 2dB SNR gain compared to the equal power allocation in the high SNR regime.