Fixed/variable power multicast over heterogeneous fading channels in cellular networks

In mobile multicast over cellular networks, the wireless fading channels for different multicast receivers are usually heterogeneous, from both instantaneous and statistical perspectives. This feature imposes significant challenges in designing efficient multicast schemes to adapt to the channel variations. We investigate the adaptive rate and power control for multicast over generally distributed broadcast fading channels in cellular networks, with the focus on the two-receiver case. Specifically, we aim at optimizing the minimum achievable average goodput over all receivers through time-sharing based rate adaptation under the fixed/variable power strategies. By developing an SNR-plane partition based method, we derive the optimal rate adaptation policy for the constant (fixed) power strategy. Moreover, we obtain the optimal power-rate adaptation policy for the variable power strategy by using the Lagrangian duality theory. Simulation results are also presented to show the performance gain obtained from our derived optimal policies.