WAVE: Wearable Analog-processed Vascular Echography

Background

The field of ultrasonic imaging is crucial for non-invasive medical diagnostics, offering detailed insights into internal body structures and physiological processes. There is a significant need for continuous, long-term monitoring of hemodynamic parameters, such as blood volume and vessel dynamics, particularly for early detection of critical conditions like hypovolemia.

Traditional wearable vital sign monitors often fail to provide timely warnings, as the body's compensatory mechanisms can mask symptoms until a severe state is reached. Conventional digital ultrasound systems are inherently power-intensive due to the necessity of high-speed analog-to-digital converters (ADCs) and extensive digital signal processing. This leads to large hardware footprints and generates massive amounts of data, making them unsuitable for compact, battery-powered, and long-duration wearable devices.

These limitations hinder the development of truly continuous and unobtrusive monitoring solutions.

Technology overview

The WAVE system is a wearable ultrasonic imaging technology that operates entirely using analog circuitry, eliminating the need for an analog-to-digital converter. It processes raw ultrasound echoes through analog amplification, filtering, envelope detection, and adaptive thresholding to generate 1-bit black-and-white images. Digitization occurs via a comparator and time-to-digital converter that records echo timing.

This system incorporates a soft, high-density piezoelectric transducer array with 1280 elements and novel soft coupling layers, transmitting processed data wirelessly via Bluetooth Low Energy from a compact, flexible PCB.

Benefits

Significantly reduced power consumption (50x) for extended battery life.
Substantially smaller hardware size (16x) for compact, wearable integration.
Dramatically lower data transmission rate (100x) for efficient wireless communication.
Improved image quality through adaptive thresholding for enhanced diagnostic sensitivity.
Enables continuous, non-invasive monitoring of vascular hemodynamics.
Facilitates early detection of critical conditions like hypovolemia.

Applications

Wearable hypovolemia detection
Continuous cuffless blood pressure
Long-term vascular health monitoring
Athlete physiological monitoring
Remote patient vital monitoring

Opportunity

This wearable ultrasonic imaging system processes raw echoes entirely through analog amplification, filtering, envelope detection, and adaptive thresholding, eliminating ADCs.
Production of 1-bit black-and-white images, digitizing timing via a comparator and TDC.
This approach drastically reduces power, size, and data throughput, integrating a high-density soft piezoelectric transducer array for wireless vascular monitoring.