Monopulse angle estimation for unresolved targets with a fourth order cumulant

Monopulse angle estimation for unresolved multiple targets in antenna mainbeam was proposed in this paper. A fourth order cumulant was introduced to increase the array's degree-of-freedom of monopulse beamformer from two to four. Subsequently, a derivative VESPA algorithm was used for calculating the multiple monopulse ratios to enable angle estimation by existing monopulse processing. Results of computer simulation were provided to illustrate the performance comparison with the four dimensional beamspace MUSIC. The results show higher accuracy than the beamspace MUSIC for the unresolved two targets scenario.