Quickest detection of a random signal in background noise using a sensor array

The problem of detecting the onset of a signal impinging at an unknown angle on a sensor array is considered. An algorithm based on parallel CUSUM tests matched to each of a set of discrete beamforming angles is proposed. Analytical approximations are developed for the mean time between false alarms, and for the detection delay of this algorithm. Simulations are included to verify the results of this analysis.