Max-Min Throughput-Optimal Multicast Link Adaptation for Non-Identically Distributed Link Qualities

We consider multicasting the same data from one base station (BS) to several user equipments (UE) over a radio interface. Transmission is slotted into transmit resource units (RU). The qualities of the transmission channels from the BS to the UEs differ between RUs and between UEs. The transmit rate can be chosen by the BS independently in each RU based on the per UE channel qualities, which are assumed to be known by the BS. For each UE we calculate the throughput as the mean information received per RU over all RUs within a scheduling unit. Here, the multicast throughput is defined as the minimum UE throughput. We present a scheme to optimize the rate selections for all RUs such that the minimum UE throughput is maximized, even in the general case that the channel qualities of UEs are non-identically distributed. The achievable gains are evaluated using radio net¬work simulations with realistic channel models.