Method and Apparatus for Determining Target Elevation Angle, Altitude and Range and the Like in a Monopulse Radar System with Reduced Multipath Errors

The present invention relates to a method and system for determining target elevation angle, altitude and range and the like in a monopulse radar system with reduced multipath errors. A transmitter/receiver unit receives monopulse sum and difference signals caused by echoes from targets. The sum and difference signals are then logarithmically-amplified in a logarithmic amplifier unit. A selector selects one of the sum and difference signals having the largest amplitude, and generates a selection signal indicating which of the sum and difference signals has the largest amplitude. The selection signal is provided to a search radar target tracking unit which determines whether a target at a given range interval and azimuth interval, for example, has been selected for tracking by an operator. The search radar target tracking unit then controls a gate unit to selectively provide either the logarithmically-amplified sum signal or the logarithmically-amplified difference signal to a peak detection unit based on the selection signal, and based on whether a particular target has been selected for tracking.