TinyProbe: A Wearable 32-channel Multi-Modal Wireless Ultrasound Probe.

The need for continuous monitoring of cardiorespiratory activity, blood pressure, bladder, muscle motion analysis, and more, is pushing for research and development of wearable ultrasound devices. In this context, there is a critical need for highly configurable, energy-efficient wearable ultrasound systems with wireless access to raw data and long battery life. Previous exploratory works have primarily relied on bulky commercial research systems or custom-built prototypes with limited and narrowly-focused field applicability. This paper presents TINYPROBE, a novel multi-modal wearable ultrasound platform. TINYPROBE integrates a 32-channel ultrasound RX/TX frontend, including TX beamforming (64 V_pp excitations, 16 delay profiles) and analog-to-digital conversion (up to 30 Msps, 10 bit), with a WiFi link (21.6 Mbps, UDP), for wireless raw data access, all in a compact (57 × 35 × 20 mm) and lightweight (35 g) design. Employing advanced power-saving techniques and optimized electronics design, TINYPROBE achieves a power consumption of < 1W for imaging modes (32 ch., 33 Hz) and < 1.3W for high-PRF Doppler mode (2 ch., 1400 Hz). This results in a state-of-the-art power efficiency of 44.9 mW/Mbps for wireless US systems, ensuring multi-hour operation with a compact 500 mAh Li-Po battery. We validate TINYPROBE as a versatile, general-purpose wearable platform in multiple in-vivo imaging scenarios, including muscle and bladder imaging, and blood flow velocity measurements.