Angle estimation in the presence of mainbeam interference with the differential EMVDR

The extended minimum variance distortionless response (EMVDR) spatial spectrum estimator is presented. MVDR and the thermal noise algorithm (TNA) can be regarded as the special cases of it. The EMVDR spectrum has, theoretically, infinite superresolution capability with increasing the power of the array covariance matrix in the white noise background; this is verified by calculations. Further, the differential EMVDR for angle estimation in the presence of mainbeam interference is derived. Simulations show that it can resolve and accurately locate targets while remarkably suppressing interference in the main target beam.