US Patent 10299095 Wireless load modulation

Techniques of load modulation are described herein. A wireless power transmitting unit may include a resonator to periodically transmit a short beacon having a first time period. The wireless power transmitting unit also includes circuitry coupled to the resonator. The circuitry is configured to detect a load change in the resonator when transmitting the short beacon and cause the resonator to transmit a long beacon subsequent to said transmitting the short beacon if said load change is detected. The long beacon has a second time period longer than the first time period.