Passive MIMO radar networks

Abstract

In distributed sensing applications, the nodes of a sensor network cooperatively detect and localize targets of interest. In particular, active multiple-input multipleoutput (MIMO) radar (AMR) uses multiple transceivers to transmit separable signals and receive the scattered returns, while passive MIMO radar (PMR) uses multiple receivers to receive the direct-path (transmitter-to-receiver) and target-path (transmitter-to-target-to-receiver) signals originated by multiple non-cooperative transmitters to detect and localize targets. This chapter surveys recent results in the theory of centralized detection in PMR networks. Generalized likelihood ratio test (GLRT)-based detectors for PMR detection have been developed and their performances are compared to related detectors for AMR and passive source localization (PSL) sensor networks. PMR detection sensitivity and ambiguity are then analyzed as a function of both the target-path and direct-path signals-to-noise ratios (SNRs). The results demonstrate that PMR detection sensitivity and ambiguity approach that of active MIMO radar sensor networks when the direct-path SNRs are sufficiently high. Conversely, PMR detection sensitivity and ambiguity approximate that of passive source localization sensor networks when the direct-path SNRs are sufficiently low. In this way, PMR networks unify these related active and passive sensor network architectures in a common theoretical framework.