Improved Spatial Resolution in a Three-Dimensional Acoustic Medical Imaging System Based on a Hybrid Method Using a Synthetic Aperture Technique

Abstract

For an acoustic real-time three-dimensional (3-D) imaging system with high spatial resolution, we propose a system based on a hybrid method using a synthetic aperture technique. We can change the transmit point in this system; thus, the coherent integration of multiple receive signals from different transmit points improves spatial resolution using a synthetic aperture technique. In the case of a time resolution of 300 3-D images/s, the -3 dB lateral resolution of the proposed system is 1.30 λ in the x–z section and 1.17 λ in the y–z section for a 0.07 m depth, where the lateral resolution is improved from 16 transmit and receive events. The number of elements can be reduced to about 1/7.5 of a dense two-dimensional (2-D) array of a digital beamforming imager having the same time and spatial resolution.