Wireless power transmission device, wireless power transmission system, and wireless power transmission method

A wireless power transmission system comprising:

• a power transmission device to transmit a wireless power signal through a plurality of first antennas;
• and
• a power receiving device to receive the wireless power signal through a second antenna, the wireless power transmission system comprising:
• a propagation path estimation unit to estimate first propagation path information characterizing a propagation path between the plurality of first antennas and a predetermined antenna, based on a propagation path estimation signal having a same frequency as a frequency of the wireless power signal and being transmitted from the predetermined antenna;
• a propagation path extraction unit to extract second propagation path information characterizing a propagation path passing through a moving body, based on at least one of a difference on a time axis of a plurality of pieces of the first propagation path information each acquired at different times, and filtering on a frequency axis;
• a weight calculator to calculate a weight vector that determines a directivity of a combined power transmission beam formed by the plurality of first antennas, based on at least one of the first propagation path information and the second propagation path information;
• and
• a controller to control an amplitude and a phase of the wireless power signal inputted to each of the plurality of first antennas, based on the weight vector.

A wireless power transmission method for performing wireless power transmission between a power transmission device to transmit a wireless power signal through a plurality of first antennas, and a power receiving device to receive the wireless power signal through a second antenna, the wireless power transmission method comprising:

• estimating first propagation path information characterizing a propagation path between the plurality of first antennas and a predetermined antenna, based on a propagation path estimation signal having a same frequency as that of the wireless power signal and being transmitted from the predetermined antenna;
• extracting second propagation path information characterizing a propagation path passing through a moving body, based on at least one of a difference on a time axis of a plurality of pieces of the first propagation path information each acquired at different times, and filtering on a frequency axis;
• and
• calculating a weight vector that determines a directivity of a combined power transmission beam formed by the plurality of first antennas, based on at least one of the first propagation path information and the second propagation path information, and controlling an amplitude and a phase of the wireless power signal inputted to each of the plurality of first antennas, based on the weight vector.