Ambient Backscatter on 4G spectrum

Video made by Romain FARA at Orange Gardens, in 2018, with Tag and Reader designed by Orange and Institut Langevin.
The system enables a battery-free RF TAG to transmit binary messages to an RF READER just by slightly perturbating RF waves coming from an ambient SOURCE such as TV, Wi-Fi or cellular, and therefore without generating any new RF wave. This week, we successfully experimented ambient backscattered communications on 4G network in 700MHz and 800MHz bands. Ambient backscattered communication has been achieved at 780MHz (4G downlink band), 795MHz(4G downlink band), 805MHz(4G downlink band) and 816MHz(4G downlink band) for a range of 50cm.