WULPUS PRO: Multi-mode Ultra-Low-Power Wearable Ultrasound and Array Imaging with CMUT Support

Wearable ultrasound enables continuous monitoring of physiological processes such as muscle dynamics, bladder volume, and cardiovascular activity. Existing fully wearable ultra-low-power platforms are limited to shallow, low-channel A-mode sensing, while larger multi-mode systems are too bulky and power-hungry for true wearability. We present WULPUS PRO, a runtime-programmable wearable ultrasound acquisition platform measuring 39 times21 times6 mm and weighing 5 g. It integrates 30 V excitation, 16 time-multiplexed channels, a low-noise receive front-end with up to 70 dB gain, 14 MHz bandwidth, time-gain compensation, and 45 dB SNR. The platform supports deep-tissue echo acquisition up to 2.2 MHz in RF-sampling mode and 8 MHz in envelope-detection mode. We demonstrate B-mode imaging in a 16-channel ultra-low-power wearable with sub-millimeter axial and millimeter-scale lateral resolution in phantom experiments, while consuming 40 mW at 50 Hz PRF and under 60 mW at 300 Hz PRF. WULPUS PRO supports both piezoelectric and capacitive micromachined ultrasonic transducers, enabling integration with skin-conformal polymer-based CMUT arrays. As a host-agnostic acquisition front-end, it exposes standard data and power interfaces for BLE- and Wi-Fi-based wearable hosts. We demonstrate wireless transmission with external BLE and Wi-Fi modules and project 1-2 days of BLE operation at 50 Hz PRF and over 3 h of Wi-Fi streaming at 300 Hz PRF using a 300 mAh, 6.4 g Li-Po cell. WULPUS PRO establishes a new class of fully programmable, B-mode-enabled, ultra-low-power wearable ultrasound platforms.