CSMA Self-Adaptation Based on Interference Differentiation

This paper addresses the design challenge of interference mitigation in the emerging high density (HD) wireless LAN. It is proposed to differentiate interference according to their energy and timing relative to desired signal, and measure packet error rate (PER) locally at transmitter for each type of interference. Then, self-adaptation algorithms are designed to adjust a) clear channel assessment (CCA) threshold, aka physical carrier sensing threshold, to leverage spatial reuse for achieving higher aggregate throughput, and b) transmit power (TP) to compensate location difference among links, and prevent individual links from starving. Compared to an end-to-end (E2E) feedback loop, ours has negligible complexity and zero over-the-air overhead. Extensive OPNET simulations are used to compare the performance of our solutions against the legacy and the ideal.