No visit to the doctor's office is complete without a blood-pressure cuff squeezing your arm and a cold stethoscope placed on your chest. But what if your vital signs could be gathered, without contact, as you sit in the waiting room or the comfort of your own home? Cornell University engineers have demonstrated a method for gathering blood pressure, heart rate and breath rate using a cheap and covert system of radio-frequency signals and microchip "tags," similar to the anti-theft tags department stores place on clothing and electronics.
The cracker-sized tags measure mechanical motion by emitting radio waves that bounce off the body and internal organs, and are then detected by an electronic reader that gathers the data from a location elsewhere in the room. The system works like radar, according to Edwin Kan, professor of electrical and computer engineering. But unlike most radar…
