Investigation of a radar site effect

An experimental investigation is described of the scattering effect responsible for large errors in the azimuth bearing measurements obtained with a 1 GHz monopulse receiver on a particular site when the signal source occupied positions near the top of a distant hill. The received field distribution on a horizontal line directly in front of the monopulse aperture was sampled by means of a travelling probe antenna and recorded holographically. Computer processing of the holograms formed images that revealed the scattering mechanism. A simulation was used to study the effects of different components of the multipath field on the monopulse measurement.