Monopulse, fan-beam, search-radar system with improved height and azimuth determination

摘要

Multipath signals are eliminated at all but the lowest elevation angles allowing monopulse techniques to be used to determine target height and azimuth in a two-dimensional, fan-beam, search-radar system. A narrow-azimuth fan beam is oriented at an angle to the vertical plane and has its boresight centered approximately on the horizon so that a V-beam is formed by the direct beam and the portion of the direct beam reflected from the surface (i.e., the portion that is below the horizon). The reflected beam does not interfere with the direct beam except in a multipath region near the reflecting surface. Frequency diversity or a receive-only beam in the vertical plane may be used to determine if a target is in the multipath region.