Minimum variance monopulse technique for an adaptive phased array radar

Abstract

Monopulse techniques allow the direction of arrival of a target to be estimated to better than a beamwidth accuracy from a single time sample of data. If adaptive beamforming is employed the sum and difference beams are distorted and the usual monopulse formulas produce errors. These errors are greatest in main beam jamming scenarios. A number of papers have been written on monopulse correction schemes which account for the distortion produced through adaptive beamforming, to produce an improved estimate of the target direction. However in the previous work, estimation noise has not been considered in detail. A new minimum variance adaptive monopulse (MVAM) scheme is developed which gives the unbiased target direction estimate least prone to the effects of noise. The advantages of MVAM over existing monopulse approaches are demonstrated using simulation data for targets set in severe clutter and mainbeam jamming environments.