Determination of lateral modulation apodization functions using a regularized, weighted least squares estimation.
Recently, work in this group has focused on the lateral cosine modulation method (LCM) which can be used for next-generation ultrasound (US) echo imaging and tissue displacement vector/strain tensor measurements (blood, soft tissues, etc.). For instance, in US echo imaging, a high lateral spatial resolution as well as a high axial spatial resolution can be obtained, and in tissue displacement vector measurements, accurate measurements of lateral tissue displacements as well as of axial tissue displacements can be realized. For an optimal determination of an apodization function for the LCM method, the regularized, weighted minimum-norm least squares (WMNLSs) estimation method is presented in this study. For designed Gaussian-type point spread functions (PSFs) with lateral modulation as an example, the regularized WMNLS estimation in simulations yields better approximations of the designed PSFs having wider lateral bandwidths than a Fraunhofer approximation and a singular-value decomposition (SVD). The usefulness of the regularized WMNLS estimation for the determination of apodization functions is demonstrated.
Sumi
Chikayoshi
C
Department of Information and Communication Sciences, Faculty of Science and Technology, Sophia University, 7-1 Kioi-Cho, Chiyoda-Ku, Tokyo 102-8554, Japan. c-sumi@sophia.ac.jp
IEEE Trans Ultrason Ferroelectr Freq Control. 2008 Dec;55(12):2607-25
19126486
IEEE Trans Ultrason Ferroelectr Freq Control. 1999;46(1):158-66
18238410
IEEE Trans Ultrason Ferroelectr Freq Control. 2004 Apr;51(4):396-409
15139541
IEEE Trans Ultrason Ferroelectr Freq Control. 1989;36(5):540-8
18290231
IEEE Trans Ultrason Ferroelectr Freq Control. 2008 Feb;55(2):297-307
18334337
IEEE Trans Ultrason Ferroelectr Freq Control. 2003 Jan;50(1):15-24
12578133
IEEE Trans Ultrason Ferroelectr Freq Control. 2007 Feb;54(2):332-42
17328330
IEEE Trans Ultrason Ferroelectr Freq Control. 2007 Apr;54(4):746-56
17441584
J Med Ultrason (2001). 2007 Dec;34(4):171-88
27278479
IEEE Trans Ultrason Ferroelectr Freq Control. 2007 Feb;54(2):301-12
17328327
IEEE Trans Ultrason Ferroelectr Freq Control. 1998;45(3):837-51
18244236
IEEE Trans Ultrason Ferroelectr Freq Control. 2008 Jan;55(1):24-43
18334311