Reducing Interference by Three Bit Scheduling Information in Wireless Local Area Networks

Abstract

For decades wireless local area networks (WLANs) using the distributed coordination function (DCF) protocol have been suffering from packet collisions causing throughput performance degradation. In order to resolve this issue, we propose a novel resource scheduling scheme, named 3 bits of reservation information (3bRI). In 3bRI, the scheduling information of the next three time slots is broadcast in ACK frames, and the information can be overheard by neighboring stations. Each active neighboring station checks the overheard scheduling information before starting a transmission, and defers its transmission to avoid a packet collision when the time slot has already been reserved. Simulation results show that the proposed method improves the total throughput performance by 55% compared to DCF, and 36% compared to centralized random backoff (CRB) when the number of active nodes is 40. It also maintains a high level of fairness to legacy devices using DCF when devices using 3bRI coexist with legacy devices.