Maximum likelihood processing with digital beamforming

The authors describe a two-stage digital beamforming architecture for use in radar. The first stage implements a fully adaptive array of subarrays while the second stage implements a fully adaptive array of beams. Maximum likelihood processing is used in the second stage to estimate target amplitude and angle of arrival. The new architecture supports improved search and track performance compared to traditional systems that use a single receive beam and monopulse processing to measure angle.