Monopulse processing for DOA estimation of two unresolved Rayleigh targets with known relative RCS

When two targets are closely-spaced with respect to the resolution of a radar, the measurements of the two targets will be merged when the target echoes are not resolved in angle, range, or radial velocity (i.e., Doppler processing). Monopulse processing is considered for Direction-Of-Arrival (DOA) estimation of two unresolved Rayleigh targets with known relative Radar Cross Section (RCS). The mean of the in-phase (i.e., the real part) monopulse ratio and the variance of the in-phase and quadrature monopulse ratios are utilized to estimate the DOAs of the two targets. Simulation results that illustrate performance of the DOA estimators are given along with simulation results for a tracking example.