Demodulation of Feedback Signal for Wireless Charging Systems According to the Qi Standard

In wireless device charging systems according to the Wireless Power Consortium's Qi standard communication from the power receiver to the power transmitter is required. Communication signal is modulated to the power signal with the backscatter modulation. This article presents the problems which arise in implementation of a demodulation of this signal on an ARM microprocessor, the STM32F407VG is used here. Appropriate measures provide minimum number of transfer errors and communication packet loss. A programming code implementation with a fast loop for signal processing and a slow loop for packet identification is proposed. It can be used in the development of devices for wireless charging, according to the Qi standard.