Distributed Power Allocation Scheme for Multi-Relay Shared-Bandwidth (MRSB) Wireless Cooperative Communication

In multi-relay shared-bandwidth (MRSB) wireless cooperative communication systems, it generally needs destination node to determine the optimal relay subset and broadcast the information to the candidate relays. One drawback to this central scheme is its high complexity and time consumption. In this letter, we propose a distributed power allocation strategy that makes the system´s Signal-Noise-Ratio (SNR) performance improve monotonically in the number of the relays. Each terminal can relay its overheard information with specified transmission power according to its own channel information separately. Consequently, the NP problem of solving the optimal relay subset in previous central mode is transformed into the problem of power allocation and distributed relay scheduling is realized in a simple way. Through Monte Carlo simulations being carried out under Rayleigh fading channel condition, the performance of the proposed scheme is highlighted by comparing with previous central mode schemes.