Delta Metric Scheduling for LTE-Advanced Uplink Multi-User MIMO Systems

Abstract

Proportional fair (PF) scheduling algorithm has been extensively utilized in many different systems, since it can support both multi-user diversity and system fairness guarantee. Brute-force searching is the optimal scheduling, pairing and ordering algorithm. However, the optimal brute-force searching method is too computationally prohibitive, especially in case of the large number of users. This paper proposes a novel 2-dimensional grid based scheduling scheme for uplink MU-MIMO transmission using either the conventional proportional fairness metric or delta scheduling metric. Comparing to the scheduling approach using the conventional priority based pairing metric, the proposed scheduling algorithm based on delta scheduling metric could obtain approximate 7% gain for both cell and cell-edge throughput gain with neglectful computational complexity increase. With the aid of successive interference cancellation, MU-MIMO with MMSE-SIC receiver could also improve the cell-edge throughput compared to SU-MIMO. The advantage of the proposed scheme is that it can improve the throughput performance without the sacrifice of the user fairness guarantee.