Network Coding for Ultra-Reliable Wi-Fi: An Experimental Study

To achieve high reliability for Wi-Fi, we propose to use network coding (NC) as a proactive inter-frame (packet-level) redundancy technique at the medium access control (MAC) layer, which has the advantage of low latency and high spectral efficiency compared to the existing retransmission and repetition techniques. In this paper, we explore practical ways to integrate NC in Wi-Fi systems and conduct over-the-air experiments in an office environment using a Wi-Fi-based platform, where NC is implemented as a software layer. The experiment results show that NC can achieve up to two orders of magnitude reliability gain over the baseline repetition scheme with the same spectral efficiency. When interferences exist in Wi-Fi transmissions, but the packet erasures are sufficiently uncorrelated, using NC can achieve very high reliability. When the correlation increases the performance gain of NC degrades, but it still maintains a significant advantage over repetition.