Angle Estimation in Amplitude Comparison Monopulse Systems

The problem of estimation of angle of arrival in amplitude comparison monopulse (ACM) radars in the presence of internally generated thermal noise is considered. A pulse-type radar is assumed and angular noise is postulated to be absent. In the treatment of the problem, explicit inclusion of various simple models for the pulse returns is made to draw a relationship between the a priori statistics of the echo signals and the ability to estimate the angle of arrival in ACM radars. A maximum likelihood analysis is made to determine the form of the estimates of angle of arrival for the various cases and the accuracy of these estimates is evaluated as a function of the signal-to-noise ratio per hit and of the number of hits. Although most of the estimates considered have already received attention, many of the results are believed to be new.