Improving 802.11 Range with Forward Error Correction

Abstract

The ISO/IEC 8802-11:1999(E) specification uses a 32-bit CRC for error detection and whole-packet retransmissions for recovery. In long-distance orhigh-interference links where the probability of a bit error is high,this strategy results in excessive losses, because any erroneous bitcauses an entire packet to be discarded. By ignoring the CRC andadding redundancy to 802.11 payloads in software, we achievedsubstantially reduced loss rates on indoor and outdoor long-distancelinks and extended line-of-sight range outdoors by 70 percent.