An Analog Front-End for Bladder Ultrasound Monitoring: Achieving 75% Reduction in RX Power Consumption through Power Gating for Intra-Image Sparsity.

Continuous bladder volume monitoring is essential for patients with impaired urinary function. While portable ultrasound probes can be used to image the bladder, they require manual operation. Wearable ultrasound devices offer a non-invasive alternative, but face challenges with power consumption that limit battery life. In this work, we propose Power Gating for Intra-Image Sparsity (PGIIS), an algorithm that reduces power consumption by selectively power gating receiver (RX) amplifiers during unimportant image regions. We also design a low-power analog front-end (AFE) integrated circuit (IC) in 180 nm BCD process to implement PGIIS, integrating an 8-channel ultrasound TX and RX chain with amplifier power gating. Testing on a phantom shows that PGIIS maintains important bladder features for volume calculation while reducing RX power by 75%, significantly extending battery life for wearable ultrasound systems.