A new device that runs on almost zero power can transmit data across distances of up to 2.8 kilometers—breaking a long-held barrier—and could lead to a vast array of interconnected devices.
For example, flexible electronics—such as knee patches that capture range of motion in arthritic patients or patches that use sweat to detect fatigue in athletes and soldiers—hold great promise for collecting medically relevant data.
But today’s flexible electronics and other sensors that can’t employ bulky batteries and need to operate with very low power typically can’t communicate with other devices more than a few feet or meters away. This limits their practical use in applications for medical monitoring, home sensing to smart cities, and precision agriculture.
By contrast, the new long-range backscatter system, which uses reflected radio signals to transmit data at extremely low power and low cost, achieve reliable coverage throughout a 4,800-square-foot house, an office area covering 41 rooms, and a one-acre vegetable farm.