Frequency modulated semi-continuous wave Doppler ultrasound: A novel method for the detection of scatterer velocity and range using wearable ultrasound instrumentation
Year: 2026
Type: preprint
Abstract: Doppler ultrasound imaging has become a key tool for clinicians and researchers to measure the velocity of blood and tissues within the human body. Current clinical instruments utilize pulsed wave or continuous wave transmissions for tracking phase shifts or frequency shifts respectively to estimate scatterer motion. However, these two techniques can also be considered as ends of a continuum along which other motion tracking techniques exist. In this paper, we explore frequency modulated semi-continuous wave (FMSCW) Doppler, an underexplored Doppler imaging technique that has particular benefits for emerging wearable ultrasound applications due to significant simplification of instrumentation and lowered data rates. We present a full technical overview of this technique, simulations exploring the impact of selected imaging parameters as well as how noise impacts imaging, and present three exemplary imaging applications in human participants using FMSCW Doppler implemented on a wearable ultrasound system. The results of the simulations evaluating the impact of imaging parameters demonstrate the trade-off between resolution in the range and velocity axis as well as the impact of scatterer range and speed on the measurement error. The three sets of images collected from human participants serve to demonstrate FMSCW Doppler used in a variety of wearable ultrasound applications including cardiovascular monitoring, rehabilitation assessment, and prosthetic device control. Furthermore, we discuss the relationship between FMSCW Doppler and isomorphic techniques from radar as well as potential inspiration for improvements for FMSCW Doppler inspired by the echolocation of bats.
Institution: George Mason University
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7222995198