Low-complexity resource allocation with rate balancing for the MISO-OFDMA broadcast channel

This paper presents a low-complexity algorithm for multiuser scheduling and resource allocation in the Multiple Input Single Output (MISO) downlink channel with Orthogonal Frequency Division Multiple Access (OFDMA). The goal of the algorithm is to maximize the sum-rate on the radio channel and to ensure that the rate assignment is suitably balanced among users. The proposed algorithm uses partial Channel State Information (CSI) and therefore has a reduced feedback requirement. It also allows an on-line implementation, based on an ergodic optimization framework with dual optimization and stochastic approximation. Performance and complexity reduction are quantified by considering comparison with other solutions in a realistic single-cell system configuration. It is shown that the algorithm is effective to balance average rate among users even in heterogeneous and non-stationary channel conditions with lower computational complexity and feedback requirements.