A Novel Localized Coherence Rule Delay-and-Multiply Algorithm Toward Long-Range Ultrasound Imaging With Narrow Field-of-View pMUTs

• Published in: IEEE sensors journal Vol. 25; no. 10; pp. 16830 - 16845
• Main Authors: Giubilei, Gaia, Sarafianou, Mantalena, Sze Wai Choong, David, Jian Goh, Duan, Koh, Yul
• Format: Journal Article
• Language: English
• Published: New York IEEE 15.05.2025; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Array signal processing; Arrays; Channels; Continuous wavelet transforms; Crosstalk; Die forming; Distortion measurement; Field of view; Image reconstruction; Imaging; Lead zirconate titanate; Lead zirconate titanates; Micromachining; Piezoelectric micromachined ultrasonic transducer (pMUT); Piezoelectricity; receive (RX) beamforming; Reflectors; Resonant frequencies; Signal processing algorithms; Signal to noise ratio; Transducers; Ultrasonic imaging
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2025.3557576

This work proposes an innovative signal postprocessing algorithm for long-range ultrasound imaging by using a narrow field-of-view (narrow-FoV) lead zirconate titanate (PZT) piezoelectric micromachined ultrasonic transducer (pMUT) array. Two <inline-formula> <tex-math notation="LaTeX">{3} \times {3} </tex-math></inline-formula> mm2 dies of a 1-D array pMUT, whose resonant frequency is 6.5 MHz, consisting of 18 channels, were employed for this demonstration. The entire system has 18 channels by electrically combining two columns of pMUT membranes as one to increase the transmission power with the cost of narrowing FoV. In this work, experimental testing using single and multiple 5-mm diameter spherical reflectors at various arrangements was performed to validate the 2-D imaging capabilities of the developed pMUT array with the proposed image reconstruction algorithm achieving a 1.5-mm lateral resolution.