Performance analysis of multi-user scheduling over time-varying channel

The sum-rate capacity of downlink channel can be significantly improved via optimal multi-user scheduling. However, in the time-varying channel, the optimal scheduling is difficult to be implemented when the dedicated feedback link existing delay. In this paper, the performance of multi-user scheduling over time-varying channel is investigated, and an analytical expression of sum-rate capacity is derived. In order to overcome the negative effect of feedback delay on system performance, an improved user scheduling is proposed based on the predicted best channel quality. Numerical simulation results demonstrate the proposed user scheduling can effectively improve the system performance, even the predictor order is 2.