SER analysis for the best relay selection with interferences for DF

In this paper, we analyze the performance of a new cooperative diversity scheme based on best relay selection with interferences at relay nodes, only relay node can be affected by interference. For the selection scenario, only a best relay that maximizes the end-toend received signal-to-interference and noise ratio (SINR) at the destination is selected to forward the information. Through statistical analyses, we establish a closed-form expression for the symbol error rate (SER), by deriving the analytical expressions for the probability density function ( PDF ), the cumulative density function ( CDF ), and the moment generating function (MGF) of the instantaneous received signal to interference and noise ratio (SINR) from relay selection. At relay nodes we use selection combiner (SC), which only process one of the diversity branches that has the highest SINR, alternatively, at the destination we used maximum ratio combiner (MRC) to combine the transmitted signals from the source and that one from the best selected relay. we show that our new scheme optimizes well the available resources (two channel links: the direct and the best relay links). Simulations are given to validate the analytical results with different number of relays and different interference power.