A new adaptive antenna for elevation angle estimation in the presence of multipath,

A new adaptive antenna is described for elevation angle estimation as encountered in low angle tracking radar. The antenna is used to sense the directions of arrival of both the direct and multipath signal in a symmetric manner. A priori knowledge of the reflection coefficient of the reflecting surface is not necessary. Computer simulation results are included to illustrate the effects of (1) signal-to-noise ratio, and (2) the phase difference between the two signals at the centre of the array, on the performance of the system.