Multilevel coincidence correlators for random signal detection

Multilevel coincidence correlators (CC´s) are considered for detecting a weak random signal common to two or more input channels against a background of independent additive noise. For two-input systems the structure of the optimum detector maximizing the efficacy is derived, and a comparison is made between the optimum CC and some suboptimal CC´s of interest. An extension of the two-input CC is considered for general multiinput systems.