An Efficient Adaptive Beamforming Method For Simultaneous Improvement Of The Resolution And Contrast Of Ultrasound Imaging

Mohammadzadeh Asl, Babak; Mahloojifar, Ali

doi:10.22041/ijbme.2009.13406

An Efficient Adaptive Beamforming Method For Simultaneous Improvement Of The Resolution And Contrast Of Ultrasound Imaging

Document Type : Full Research Paper

Authors

Babak Mohammadzadeh Asl ¹

Ali Mahloojifar ²

¹ PhD Candidate, Department of Biomedical Engineering, School of Electrical and Computer Engineering, Tarbiat Modares University

² Associate Professor, Department of Biomedical Engineering, School of Electrical and Computer Engineering, Tarbiat Modares University

https://doi.org/10.22041/ijbme.2009.13406

Abstract

In recent years, adaptive beam forming methods have been successfully applied to medical ultrasound imaging, resulting in significant improvement in image quality compared to non-adaptive beam formers. This improvement results from the fact that their weights are chosen based on the priori knowledge of the received data and updated using current statistics of the array signal. Most of the adaptive beam formers presented in the ultrasound imaging literature are based on the minimum variance (MV) beam former, which can improve the imaging resolution while retaining the contrast. It is desirable that the beam former could improve the resolution and contrast, at the same time. To this end, in this paper, we have used temporal averaging besides the conventional spatial averaging to estimate the more accurate covariance matrix. Moreover, we have used the coherence factor weighting combined with MV beam forming to enhance the focusing quality and hence reducing the undesired side lobes. The efficacy of the proposed adaptive beam forming approach is demonstrated via a number of simulated and experimental examples.

Keywords

ultrasound imaging

Resolution

contrast

Adaptive Beam Forming

Minimum Variance Beam Forming

Coherence Factor Weighting

Temporal Averaging

Covariance Matrix Estimation

Subjects

Biomedical Image Processing / Medical Image Processing

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