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arXiv · 2407.09022

Improvement of Sensitivity of Capacitive Micromachined Ultrasound Transducer

Yifan Wang·Yunfei Liu
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Abstract

Capacitive Micromachined Ultrasonic Transducer (CMUT) has a wild range of applications in medical detecting and imaging fields. However, operating under self-generating-self-receiving (SGSR) method usually results in poor sensitivity. But the sensitivity cannot be improved simply by increasing the resonant frequency since the frequency of a specific kind of CMUT is designed for specific usage. In this paper, based on one specific type of CMUT, mechanical model is built and simulation analysis is demonstrated. A brand-new method one-generating-multiple-receiving (OGMR) is introduced and a special circuit model has been designed to improve the signal to thermal noise ratio. By increasing the number of receiving capacitors from 1 to 8, we increased the signal-noise ratio to 2.83 times.

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Yifan Wang, Yunfei Liu. 2024-07-12. Improvement of Sensitivity of Capacitive Micromachined Ultrasound Transducer. https://arxiv.org/abs/2407.09022

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