Optimal power and rate allocation framework for the uplink with individual average rate requirements

For delay-tolerant data applications in a wireless system, using average throughput as a quality of service (QoS) measure results in more efficient resources allocation strategies compared to using instantaneous signal to interference and noise ratio (SINR). By adapting both power and rate in a multiuser multi-antenna system based on the channel conditions, the overall power consumption can be greatly reduced. In this paper, we establish a general framework for optimal power and rate allocation when there is an average throughput constraint for each user. A key feature of the framework is that it allows consideration and evaluation of a wide range of practical receiver structures. The structural results show that the range of optimal rate and power allocation policy can be specified by a set of optimization problems over vectors, one for each fading state. The rate constraints are taken care by a rate weight vector mu, which can be tracked by a stochastic approximation algorithm. The performances of different receiver structures are compared numerically.