One of the challenges of getting more speed for wireless devices like smartphones is in devising more efficient ways of delivering wireless signals. MIT says that the trend to solve that issue has been to add antennas to the transmitter, such as the WiFi router or cell tower, or the phone or laptop. Adding more antennas is a challenge for a variety of reasons.
MIT researchers looked at the problem differently, and rather than focusing on the transmitters and receivers, they tried to amplify the signal by adding antennas to an external surfaces in the environment. The idea turned into a project called RFocus, which is a software-controlled “smart surface” that uses more than 3,000 antennas to maximize the strength of the signal at the receiver.
Tests show that RFocus could improve the average signal strength by a factor of almost 10. The team says that the platform is also very cost-effective, with each of the antennas costing only a few cents. The low cost of the antennas is thanks to the fact that they don’t process the signal at all; they only control how it is reflected.
MIT researchers believe that their system represents the largest number of antennas ever used for a single communications link. The system could serve as another form of the WiFi range extender. However, the team feels the most valuable uses could be in network-connected homes and factories of the future.
They envision a factory with hundreds of sensors for monitoring machines and inventory. RFocus is a two-dimensional surface composed of thousands of antennas that can each let the signal through or reflect it. The state of the elements is controlled by software developed at MIT to maximize the signal strength at a receiver.