Detection and source location of weak cyclostationary signals: simplifications of the maximum-likelihood receiver

The problem of dual-receiver interception of low-SNR signals, which includes detection of the presence of a particular signal type and location of its source, is considered. In particular, source-location based on time-difference-of-arrival (TDOA) measurements is examined, and the low-SNR maximum-likelihood receiver for joint detection and TDOA estimation is taken as a starting point. By explicitly revealing the way in which this receiver exploits the spectral correlation properties of the cyclostationary signal, several partial implementations with optimality properties of their own are proposed. These greatly simplified implementations, which require only a one-dimensional search over the TDOA parameter, are shown by simulation to perform competitively with the relatively complicated maximum-likelihood receiver which requires a two- or three-dimensional search for phase-shift keyed (PSK) signals