Abstract:

In conventional multicast scheme, the total throughput of multicast group is constrained by user with the worst channel quality. In order to overcome this problem of limited throughput, a resource allocation algorithm is proposed based on reducing feedback strategy and joint coding strategy for multicast systems. The layered coding combined with Reed-Solomon (RS) coding strategy which divides the multicast data into many layers is explored and compensated for data packet loss. In order to reduce the feedback load of uplink, different feedback strategies are given for different layers data. The optimal problem for resource allocation is formulated as well. In order to reduce the computational complexity, the suboptimal proportional fairness subcarrier allocation algorithm and water-filling power allocation algorithm with quality of service guarantees are presented. To further reduce the complexity, a power allocation algorithm with increasing fixed power (IFP-Q) is also proposed. Simulation shows that the proposed reducing feedback strategy can reduce more the feedback load of uplink, and the joint coding strategy can further improve the performance of systems.

Key words: multicast, fine granularity scalability video coding, reed-solomon coding, resource allocation, reducing feedback strategy