Data transmission method and device in wireless power transmission system

A wireless power transmitter, comprising:

• a power converter related to transferring wireless power to a wireless power receiver;
• and
• a communicator/controller related to communicating with the wireless power receiver and controlling transfer of the wireless power,
• wherein the wireless power transmitter is configured to:
• receive, from the wireless power receiver in a negotiation phase, a specific request (SRQ) data packet,
• wherein the wireless power transmitter establishes a power transfer contract with the wireless power receiver in the negotiation phase based on the SRQ data packet;
• and
• perform, with the wireless power receiver in a power transfer phase, a communication based on a frequency shift keying (FSK) based on the power transfer contract,
• wherein the SRQ data packet includes a specific field representing a number of cycles which make up one FSK bit,
• wherein the wireless power transmitter transmits a data transport stream to the wireless power receiver in the power transfer phase,
• wherein the data transport stream includes an initial auxiliary data control (ADC) data packet opening the data transport stream, an auxiliary data transport (ADT) data packet, a final ADC data packet closing the data transport stream, and
• wherein a maximum size of the ADT data packet increases based on decreasing the number of cycles.

A method for receiving a wireless power in a wireless power transfer system, the method performed by a wireless power receiver and comprising:

• transmitting, to a wireless power transmitter in a negotiation phase, a specific request (SRQ) data packet,
• wherein the wireless power receiver establishes a power transfer contract with the wireless power transmitter in the negotiation phase based on the SRQ data packet;
• and
• performing, with the wireless power transmitter in a power transfer phase, a communication based on a frequency shift keying (FSK) based on the power transfer contract,
• wherein the SRQ data packet includes a specific field representing a number of cycles which make up one FSK bit,
• wherein the wireless power receiver receives a data transport stream from the wireless power transmitter in the power transfer phase,
• wherein the data transport stream includes an initial auxiliary data control (ADC) data packet opening the data transport stream, an auxiliary data transport (ADT) data packet, a final ADC data packet closing the data transport stream, and
• wherein a maximum size of the ADT data packet increases based on decreasing the number of cycles.