How to Select the OOK Detection Threshold in Wireless Ad Hoc and Sensor Networks

On-Off Keying (OOK) is an attractive modulation technique to reducing energy consumption of power-constrained wireless networks. The OOK detection threshold, however, must be carefully selected to minimize the Bit Error pRobability (BER). This is a challenging task to accomplish on resource-limited nodes or on networks with high-mobility. In this paper, an efficient algorithm to compute the optimal threshold is proposed. The system scenario considers nodes simultaneously transmitting over same frequencies in Rayleigh-log-normal or Rice-log-normal fading conditions. It is shown that by using the Stirling expansion for the BER, and a log-normal approximation, a quick contraction-mapping can be build to achieve the threshold numerically.