Plane wave image formation in spatial-temporal frequency domain

Frequency-domain image formation applied to plane wave transmits of different steering angles is discussed. The processing consists of the following major steps: a) Fourier transform in both time and space, b) interpolation to remap from temporal frequency to spatial frequency in the range direction, and c) inverse Fourier transform. Several unique issues are discussed, including frequency-unwrapping in the lateral spatial frequency dimension to accommodate transmit waves of different steering angles; methods for reducing frequency-domain interpolation errors; and apodization in spatial-temporal frequency domain to achieve the equivalent of dynamic receive aperture growth and apodization.