A MCU Based Wearable Multi-Channel Ultrasound System Matching High-Frequency PMUT Arrays for Superficial Arterial Monitoring

Piezoelectric micromachined ultrasonic transducers (PMUTs) offer significant advantages including small size, low power consumption, better impedance matching with human tissue, making them particularly suitable for wearable vascular monitoring. The ultrasound monitoring of superficial blood vessels (such as the radial artery) needs to be done at high frequencies, typically 5MHz to 10MHz. This imposes stringent requirements on wearable signal processing systems. This work presents a 8-channel miniature ultrasound platform using STM32 microcontroller to match PMUT arrays under 7.5MHz for radial arterial monitoring. Using linear PMUT array and through performing sequential channel measurements, the one corresponding to the maximum arterial diameter is selectively activated to enable long-term blood pressure monitoring. Our proposed platform can achieve real-time monitoring of radial artery pulsations. This method can also be extended to other superficial vessels, such as the carotid artery.