Short-Range Small-Form-Factor 2D Source Localization Using pMUT-Based Delay-Multiply-and-Sum Imaging Towards Catheter Coordination

This work presents, for the first time, in-immersion source localization using an imaging scheme with a lead zirconate titanate (PZT) piezoelectric micromachined ultrasonic transducer (pMUT) array. Initially, the received data is calibrated and bandpass filtered to removed undesired signal contributions. For the image reconstruction, Delay-Multiply-and-Sum with multiplier-of-2-signals (DMAS2) processing is employed with the source position determined from the coordinates of the pixel of maximum intensity within the reconstructed image. Experimental data are collected using PZT pMUTs immersed in a FC-70 fluid for the validation of the method with the results denoting that the proposed method accurately localizes the source with a 91.6% mean range accuracy and a 3.6° angle absolute error across an impressive -40°/+40° Field-of-View. The impressive results for the first time, benchmark pMUT-based imaging for catheter coordination (i.e., external source tracking of an internal invasive catheter).