METHOD FOR DETECTING FOREIGN MATERIAL, AND APPARATUS AND SYSTEM THEREFOR

A power reception method for a wireless power receiver, the power reception method including storing information on a reference quality factor and a reference peak frequency; generating a foreign object detection (FOD) status packet including the information on the reference quality factor and the reference peak frequency and a packet having a length of eight bits; transmitting the FOD status packet to a wireless power transmitter; receiving a foreign object detection indicator indicating whether a foreign object is present in a charging area of the wireless power transmitter in response to the FOD status packet; performing differential bi-phase encoding for binary data of the packet having a length of eight bits; performing byte encoding for binary data of the differential bi-phase encoded packet; and transmitting the byte encoded packet to the wireless power transmitter, wherein the byte encoding is inserting a start bit, a stop bit, and a parity bit into binary bit stream of the differential bi-phase encoded packet.