Radio frequency waves to power medical devices

MIT researchers have developed a prototype implant that could offer doctors new ways to diagnose, monitor, and treat diseases. It is currently about the size of a grain of rice and powered by radio frequency waves, and can power and communicate with medical devices implanted 10cm deep within the human body from a distance of 1m.

Radio waves usually dissipate as they pass through the body, so the researchers devised In Vivo Networking (IVN), a system that relies on an array of antennas that emit radio waves of slightly different frequencies to overcome that obstacle. Radio waves overlap as they travel and where the high points overlap, sufficient energy can be produced to power an implanted sensor. Because the power is transmitted over a large area, multiple devices can be powered at the same time and the exact location of the devices does not have to be known. The researchers have said that when the sensor on the device receives a burst of power, it also gets a signal instructing it to send information back to the antenna, so it could also be used to stimulate a burst of electricity, a pulse of light or the release of a drug.
Giovanni Traverso, an assistant professor at Brigham and Women’s Hospital (BWH), Harvard Medical School, a research affiliate at MIT’s Koch Institute for Integrative Cancer Research said: “Having the capacity to communicate with these systems without the need for a battery would be a significant advance. These devices could be compatible with sensing conditions as well as aiding in the delivery of a drug”