DEVICE AND METHOD FOR PERFORMING AUTHENTICATION IN WIRELESS POWER TRANSFER SYSTEM

A wireless power transmitter including a power converter configured to transfer a wireless power to a wireless power receiver; and a communicator/controller configured to control the wireless power. Further, the communicator/controller is further configured to transmit, to the wireless power receiver, a bit pattern requesting permission to communicate; receive, from the wireless power receiver, a response packet granting the permission in response to the bit pattern; and transmit, to the wireless power receiver in a power transfer phase in which the wireless power is transferred, an auxiliary data transport (ADT) data packet after receiving the response packet. In addition, a header of the ADT data packet is set to a value informing a retransmission of a previous ADT data packet, based on receiving a not acknowledge (NAK) in response to the previous ADT data packet from the wireless power receiver.