Low-Complexity Power Allocation With Network-Coded Cooperation for Single-Carrier Transmission

We consider a power allocation algorithm in a network-coded system with iterative detection for single-carrier transmission. To achieve high network coding gain, the power fraction of each user should be allocated according to channel state information. To facilitate the power allocation, we first develop a density evolution technique for the iterative detection scheme. We then investigate the distribution of optimal power fraction by an exhaustive search. Based on the distribution, we propose a quantization-based power allocation algorithm with a low complexity. In simulations, the proposed algorithm significantly improves the network coding gain.