ModulUS: A Sandbox for High-Resolution Wearable Ultrasound Development

We introduce ModulUS, a modular sandbox platform for wearable ultrasound (US) development. The four-board system integrates a 32-channel pulser, an analog frontend (AFE) with bandwidth reduction, and an ARM Cortex-M4 microcontroller (MCU) with a dual 5Msps, 12bit analog-digital converter (ADC), each implemented as a swappable module to support rapid prototyping and evaluation of alternative circuit architectures. To demonstrate its functionality, we validated the AFE board, which reduces the effective signal bandwidth by a factor of 4 while preserving structural features, with envelope fidelity confirmed against digital Hilbert transforms (R<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> = 0.88). Compared to State-of-the-Art (SoA) platforms, ModulUS-derived designs set a new benchmark in power efficiency, achieving the lowest reported average power normalized by excitation frequency (0.6mW/MHz), down to two orders of magnitude below existing MCU- and Field Programmable Gate Arrays (FPGA)-based systems. By shifting bandwidth reduction (BWR) into the analog domain, ModulUS enables high-frequency, low-power US acquisition and establishes a flexible, reconfigurable testbed for next-generation wearable US technologies.