A Novel SDN Design to Support SIC for WiFi Networks

摘要

Successive interference cancellation (SIC) allows a receiver to decode packets that arrive concurrently, and therefore has great potential to boost the system throughput. However, in existing CSMA/CA-based designs that support SIC, there are two drawbacks: 1. the serial-execution of channel contention and data transmission over the whole channel will lead to low channel utilization, 2. when multiple packets transmit concurrently, the disparity of the transmission times will waste channel capacity. In this paper, we propose a novel SDN-based design called Multi-CQ. In Multi-CQ, we allow the concurrent execution of channel contention and data transmission over two subchannels, thereby overcoming the first drawback. Meanwhile, we adopt a centralized control mechanism to reduce the time disparity of concurrent packet transmission, thereby overcoming the second drawback. As a result, Multi-CQ can achieve higher throughput than existing designs. Extensive simulations verify the efficiency of Multi-CQ.