Abstract:

An adaptive subcarrier and power allocation scheme based on limited feedback for multicast relay networks is proposed. The new scheme works in three steps. Firstly, transfer mode of each multicast group is determined using a new feedback algorithm and transfer protocol. Secondly, a fair subcarrier allocation scheme is proposed to achieve a tradeoff between fairness and qualityofservice. Finally, a new cooperative power iterative scheme is introduced to allocate power effectively, where target rate on each subcarrier is computed by waterfilling algorithm in the first place and then a power iterate process is implemented to optimize power allocation. Simulations show that the new scheme significantly reduces feedback overhead. Moreover, both the required power and the multicast service outage of the scheme are much less than those of the direct scheme.

Key words: multicast, cooperative diversity, resource allocation