Asymptotically optimal detection/localization of LPI signals of emitters using distributed sensors

The interception of low probability of intercept signals has become increasingly difficult due to the availability of waveform agile transmitters and increased spectral bandwidth. Current detection techniques based on energy detection ignore the important cross-sensor correlation information. Additionally, existing TDOA/FDOA based localization techniques pair up the sensors and perform only pair-wise processing which is highly inefficient. To circumvent this problem we show how to use multiple spatially distributed sensors to detect and localize an emitter whose waveform is completely unknown. We present the generalized likelihood ratio detector which optimally combines the multiple sensor information for improved detection. Additionally, as part of the detector the MLE for target location is available, leading to improved localization.