Suboptimal Power Allocation for a Two-Path Successive Relay System with Full Interference Cancellation

Although power allocation considerably affects the symbol error rate (SER) performance of a two-path successive relay system (TPSRS), it is not yet studied in a full interference cancellation (FIC) scenario. In this paper, we develop a suboptimal power allocation scheme for the TPSRS-FIC through minimizing an SER-based cost function. To obtain a closed-form power allocation solution, the cost function is defined as a part of the Taylor series expansion of the theoretical SER. Simulation results show that the proposed scheme can provide almost the lowest SER under limited power resources.