Coherent detection and ambiguity resolution for Frequency Diversity Separated Subarray Radar

Radar system using separated subarrays can improve both angular accuracy and resolution at a reduced cost as well as easier transportation. However, the inherent ambiguities due to the existence of grating lobes deteriorate the performance greatly. Frequency diversity technique can be adopted to reduce the ambiguities. In this paper we have investigated the coherent detection and ambiguity resolution performance of the Frequency Diversity Separated Subarray Radar (FDSSR). We have introduced a structure that is suitable for spacial and temporal coherent processing. Based on this structure, one detector is developed for detection of target with unknown amplitude embedded in Additive White Gaussian Noise (AWGN) with known power using the generalized likelihood ratio test (GLRT). Performance of this detector has been evaluated analytically. The results show that the FDSSR with coherent processing obtains better performance compared with its counterpart using single frequency.