A Robust Approach to Generalized Sidelobe Canceler for Medical Ultrasound Imaging

作者:Li, Jiake; Wang, Yi*; Chen, Xiaodong; Yang, Jin; Yu, Daoyin
来源:Journal of Medical Imaging and Health Informatics, 2018, 8(1): 88-93.
DOI:10.1166/jmihi.2018.2238

摘要

Generalized sidelobe canceler (GSC) is a kind of realizing structure to adaptive beamforming for medical ultrasound imaging. To realize GSC people usually assume that the tissues of human are homogenous with a fixed value of ultrasound speed, despite the fact that the ultrasound speed is variable within different tissues. In this paper, signal subspace construct by eigenvectors of the sample covariance matrix is firstly investigated to optimize the steering vector, leading to a new approach named robust generalized sidelobe canceler (robust-GSC). It reduces the influence of speed error, achieves better lateral resolution when speed error exists, which is more suitable for medical ultrasound imaging. Beamforming responses of scattering points based on Field II show that robust-GSC improves the lateral resolution by 40.5% and 78.3% respectively compared with traditional GSC and synthetic aperture (SA) when existing 5% speed error. Meanwhile, if 10% speed error exists, robust-GSC improves the lateral resolution by 43.0% and 63.4% compared with GSC and SA. Simulated experiments of circular cysts show robust-GSC improves the lateral resolution by 33.9% compared with GSC in average. Real echo data experiment also indicates the newly robust-GSC can improve the imaging quality when sound speed error exists.