In-band and out-band communication method and device in wireless power transmission system
The present invention relates to a near field communication method and device in a wireless power transmission system. A wireless power receiving device comprises: a power pick-up circuit configured to receive wireless power from a wireless power transmitting device having a primary coil by magnetic coupling to the wireless power transmitting device at an operating frequency and convert an alternating current signal generated from the wireless power into a direct current signal; a communication circuit configured to perform in-band communication with the wireless power transmitting device by using the operating frequency and perform out-band communication with the wireless power transmitting device or another device by using a frequency other than the operating frequency; and a control circuit configured to control an overall operation of the wireless power receiving device, wherein a first connection parameter for out-band communication between the wireless power transmitting device and the wireless power receiving device can be set equal to a second connection parameter for out-band communication between the wireless power transmitting device and another wireless power receiving device.
1. A wireless power receiver comprising:
a power pickup circuit configured to:
receive a wireless power from a wireless power transmitter by a magnetic coupling with the wireless power transmitter having a primary coil at an operating frequency, and
convert an AC signal generated by the wireless power into a DC signal;
a communication circuit configured to:
perform an in-band communication with the wireless power transmitter using the operating frequency, and
perform an out-band communication with the wireless power transmitter or other device using a frequency other than the operating frequency; and
a control circuit configured to control an overall operation of the wireless power receiver,
wherein the communication circuit in the wireless power receiver includes:
a first out-band communication module configured to perform the out-band communication with the other device using the frequency other than the operating frequency; and
a second out-band communication module configured to perform the out-band communication with the wireless power transmitter using the frequency other than the operating frequency,
wherein, according to the second out-band communication module operating as a scanner, the second out-band communication module shares information about a scan record with the first out-band communication module,
wherein, according to the second out-band communication module operating as a master after the second out-band communication module operating as the scanner connects with the wireless power transmitter, the second out-band communication module shares scheduling information with the first out-band communication module,
wherein the second out-band communication module receives or transmits information related to a wireless charging from or to the wireless power transmitter, and
wherein, according to the second out-band communication module receiving a retransmission request for a packet transmitted by the wireless power receiver from the wireless power transmitter, the second out-band communication module reshares the scheduling information with the first out-band communication module.
2. The wireless power receiver of claim 1 , wherein the scheduling information includes a connection interval and a channel map for an out-band communication.
3. The wireless power receiver of claim 1 , wherein the communication circuit filters a packet based on at least one of a device identifier and a service identifier included in the packet received through the out-band communication.