People with diabetes will be able to monitor their blood sugar without drawing blood, using a radar sensor being developed at the University of Waterloo.

In a recent study, a large research team led by Waterloo Engineering professor George Shaker combined radar and artificial intelligence (AI) technologies to detect changes in glucose levels without painful finger pricks several times a day.

“We want to sense blood inside the body without actually having to sample any fluid,” said Shaker, a professor of mechanical and mechatronics engineering and electrical and computer engineering. “Our hope is this can be realized as a smartwatch to continuously monitor glucose.”

The system being developed at Waterloo uses radar to send high frequency radio waves into liquids containing various levels of glucose. Information in the reflected radio waves is converted into digital data for analysis by machine-learning AI algorithms developed by the researchers. The software is capable of detecting glucose changes based on more than 500 wave features or characteristics, including how long it takes for the signal to bounce back to the device.

The research involves collaboration with Google and German hardware company Infineon, which jointly developed a small radar device operating around 60 GHz and sought input from select teams around the world on potential applications.

"Correlation was amazing"

Initial tests with volunteers at the Research Institute for Aging in Waterloo achieved results that were 85 percent as accurate as traditional, invasive blood analysis.

“The correlation was actually amazing,” said Shaker. “We have shown it is possible to use radar to look into blood to detect changes.”

Next steps include refining the system to precisely quantify glucose levels and obtain results through the skin, which complicates the process. Researchers are also working with Infineon to shrink the radar device so that it is both low cost and low power.

Goal is a device like a smartwatch

The data analyzed by AI algorithms is now sent wirelessly to computers, but the ultimate aim is self-contained technology similar to smartwatches that monitor heart rate.

“I’m hoping we’ll see a wearable device on the market within the next five years,” said Shaker. “There are challenges, but the research has been going at a really good rate.”

Collaborators at Waterloo include electrical and computer engineering professor Safieddin (Ali) Safavi-Naeni, kinesiology professor Richard Hughson and numerous students.

A study on the research, Non-invasive monitoring of glucose level changes utilizing a mm-wave radar system, was published this month in the International Journal of Mobile Human Computer Interaction.