Beamforming using spatial matched filtering with annular arrays

A linear array beamforming method for ultrasonic B -mode imaging using spatial matched filtering (SMF) and a rectangular aperture geometry was recently proposed Kim , [ J. Acoust. Soc. Am. 120 , 852-861 ( 2006 )] . This letter extends those results to include circularly symmetric apertures. SMF applied to annular arrays can improve the lateral resolution and echo signal-to-noise ratio as compared with conventional dynamic-receive delay-sum beamforming. At high frequencies, where delay and sum beamforming is problematic, SMF showed greatly improved target contrast over an extended field of view.