Distributed cooperative multicast in wireless networks: Performance analysis and optimal power allocation

For wireless multicast applications where a group of users subscribe to the same service and receive the same data, a promising solution to combat channel fading is to explore the cooperative diversity and let users help each other forward packets. This paper investigates a distributed cooperative multicast scheme that uses a maximal ratio combiner to enhance the received signal-to-noise ratio (SNR), and provides a thorough performance analysis. We derive a close-form formulation of the average outage probability, examine its asymptotic behavior in the high SNR regime, and investigate the optimal power allocation. Our analytical and simulation results show that cooperative multicast performs better in denser networks with more relays helping, and user cooperation can significantly reduce the outage probability, especially in the high SNR region.