Accurate bit-error rate estimation for residual wireless channels using partial FEC

Real-time bit-error rate (BER) estimates of a wireless channel are required by many wireless applications and protocols. Surprisingly, however, there are very few estimation techniques that can accurately estimate the channel BER at residual channels above the physical layer. In this paper, we first show that traditional BER estimation techniques based on pilot bits, FEC and SNR cannot estimate a residual wireless channel's BER accurately. Therefore, we propose a novel, simple and accurate technique which estimates the BER by applying Partial FEC on disjoint sub-blocks of a packet. We analytically show that performance of any BER estimation technique is dependent on the number of bits used to infer BER and that the proposed scheme uses more bits to infer BER than the traditional methods under realistic channel conditions. We use a comprehensive 802.11b dataset to empirically compare the performance of the proposed scheme with other schemes. Simulation results validate our theoretical finding that the proposed scheme significantly outperforms traditional BER estimation techniques.