Apple Inc.
Wireless charging device with multi-tone data receiver

Abstract:

A wireless power transmitting device transmits wireless power signals modulated at a given power frequency to a wireless power receiving device using a wireless power transmitting coil. The wireless power receiving device may transmit data signals to the wireless power transmitting device. The wireless power transmitting device may include a data receiver that is coupled to the wireless power transmitting coil and that receives the transmitted data. The data receiver may include an input stage, bandpass filter circuitry, demodulator circuitry, and a data stream combiner. The bandpass filter circuitry may include at least two bandpass filter circuits for passing through signals at the power frequency and some harmonic of the power frequency. The demodulator circuitry may extract amplitude and phase information from the bandpass filtered signals and to generate multiple demodulated data streams. The data stream combiner may correlate the demodulated data streams and combine the correlated data streams.