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A novel adaptive apodization to improve the resolution of phased subarray imaging in medical ultrasound

  • Masume Sadeghi
  • Ali MahloojifarEmail author
Original Article–Physics & Engineering
  • 34 Downloads

Abstract

Purpose

Phased subarray imaging (PSA) was previously proposed to extend the receive aperture length. Using overlapped subarrays as transmitters in PSA leads to decrement of sidelobe levels of the overall beam compared to full phased array imaging (PHA). This paper proposes an adaptive compounding of subarray images in PSA to improve both the resolution and contrast compared with PHA.

Method

Adaptive apodization (ADAP) is defined proportional to the beamformed responses of subarrays such that the overall energy after compounding is minimized.

Results

The simulation and experimental results validate the performance of applying ADAP in PSA. The full width at half maximum (FWHM) at a depth of 30 mm in the proposed PSA is about 0.2 mm, compared to a FWHM of 0.6 mm with PHA imaging. Measuring the contrast ratio index shows that the ADAP method also improves the contrast in PSA imaging at least 25% compared to PHA imaging.

Conclusion

Applying the proposed ADAP, besides conventional compounding in PSA imaging, leads to improvement of both the resolution and contrast compared to PHA imaging.

Keywords

Phased subarray imaging Adaptive apodization Resolution Contrast 

Notes

Compliance with ethical standards

Conflict of interest

There is no conflict of interest.

Ethical considerations

This article does not contain any studies with human or animal subjects performed by any of the authors.

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Copyright information

© The Japan Society of Ultrasonics in Medicine 2019

Authors and Affiliations

  1. 1.Department of Biomedical EngineeringTarbiat Modares UniversityTehranIslamic Republic of Iran

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