On the performance degradation from one-bit quantized detection

It is common signal detection practice to base tests on quantized data and frequently, as in decentralized detection, this quantization is extreme: to a single bit. As to the accompanying degradation in performance, certain cases (such as that of an additive signal model and an efficacy measure) are well-understood. However, there has been little treatment of more general cases. In this correspondence we explore the possible performance loss from two perspectives. We examine the Chernoff exponent and discover a nontrivial lower bound on the relative efficiency of an optimized one-bit quantized detector as compared to unquantized. We then examine the case of finite sample size and discover a family of nontrivial bounds. These are upper bounds on the probability of detection for an unquantized system given a specified quantized performance, given that both systems operate at the same false-alarm rate.