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

Abstract

A wireless power transmission device includes a power transmitter to transmit a wireless power signal through a plurality of first antennas, 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, 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, and a controller to control an amplitude and a phase of the wireless power signal inputted to each of the plurality of first antennas.

1 . An electronic device comprising
 a power transmitter to transmit a wireless power signal through a plurality of first antennas; and   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.   
     
     
         2 . The electronic device according to  claim 1 , further comprising:
 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 first propagation path information.   
     
     
         3 . The electronic device according to  claim 2 , further comprising:
 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, wherein   the controller controls the amplitude and the phase of the wireless power signal inputted to each of the plurality of first antennas, based on at least one of the first propagation path information and the second propagation path information.   
     
     
         4 . The electronic device according to  claim 3 , further comprising:
 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,   wherein the controller controls the amplitude and the phase of the wireless power signal inputted to each of the plurality of first antennas, based on the weight vector.   
     
     
         5 . The electronic device according to  claim 1 , wherein
 the predetermined antenna is a second antenna of a power receiving device to receive the wireless power signal transmitted from the power transmitter; and   the propagation path estimation unit estimates first propagation path information characterizing a propagation path between the plurality of first antennas and the second antenna, based on the propagation path estimation signal transmitted from the power receiving device through the second antenna.   
     
     
         6 . The electronic device according to  claim 1 , wherein
 the predetermined antenna is a third antenna provided in the power transmitter; and   the propagation path estimation unit estimates first propagation path information characterizing a propagation path between the plurality of first antennas and the third antenna, based on the propagation path estimation signal transmitted by the third antenna.   
     
     
         7 . The electronic device according to  claim 6 , wherein
 the third antenna is a part of a first antenna among the plurality of first antennas provided in the power transmitter; and   the power transmitter comprises a signal source to generate the wireless power signal and the propagation path estimation signal.   
     
     
         8 . The electronic device according to  claim 1 , wherein
 the predetermined antenna is a fourth antenna of a moving-body detection device provided separately from the electronic device and a power receiving device to receive the wireless power signal transmitted from the power transmitter; and   the propagation path estimation unit estimates first propagation path information characterizing a propagation path between the plurality of first antennas and the fourth antenna, based on the propagation path estimation signal transmitted by the fourth antenna.   
     
     
         9 . The electronic device according to  claim 4 , wherein
 the predetermined antenna is a second antenna of a power receiving device to receive the wireless power signal transmitted from the power transmitter,   the propagation path estimation unit estimates first propagation path information characterizing a propagation path between the plurality of first antennas and the second antenna, based on the propagation path estimation signal transmitted by the second antenna from the power receiving device, and   the weight calculator calculates the weight vector so that a power transmission beam at a position of the moving body becomes a null and transmission of wireless power to the power receiving device is performed.   
     
     
         10 . A 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 power transmission device 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 transmitted from the predetermined antenna.   
     
     
         11 . The system according to  claim 10 , wherein
 the power transmission device further comprises 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 first propagation path information.   
     
     
         12 . The system according to  claim 11 , wherein
 the power transmission device comprises 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, wherein   the controller controls the amplitude and the phase of the wireless power signal inputted to each of the plurality of first antennas, based on at least one of the first propagation path information and the second propagation path information.   
     
     
         13 . The system according to  claim 12 , wherein
 the power transmission device further comprises 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, wherein   the controller controls the amplitude and the phase of the wireless power signal inputted to each of the plurality of first antennas, based on the weight vector.   
     
     
         14 . The system according to  claim 10 , wherein
 the predetermined antenna is a second antenna of a power receiving device to receive the wireless power signal transmitted from the power transmitter; and   the propagation path estimation unit estimates first propagation path information characterizing a propagation path between the plurality of first antennas and the second antenna, based on the propagation path estimation signal transmitted from the power receiving device through the second antenna.   
     
     
         15 . The system according to  claim 10 , wherein
 the predetermined antenna is a third antenna provided in the power transmitter; and   the propagation path estimation unit estimates first propagation path information characterizing a propagation path between the plurality of first antennas and the third antenna, based on the propagation path estimation signal transmitted by the third antenna.   
     
     
         16 . The system according to  claim 15 , wherein
 the third antenna is a part of a first antenna among the plurality of first antennas provided in the power transmitter; and   the power transmitter comprises a signal source to generate the wireless power signal and the propagation path estimation signal.   
     
     
         17 . The system according to  claim 10 , wherein
 the predetermined antenna is a fourth antenna of a moving-body detection device provided separately from the system and a power receiving device to receive the wireless power signal transmitted from the power transmitter; and   the propagation path estimation unit estimates first propagation path information characterizing a propagation path between the plurality of first antennas and the fourth antenna, based on the propagation path estimation signal transmitted by the fourth antenna.   
     
     
         18 . The system according to  claim 13 , wherein
 the predetermined antenna is a second antenna of a power receiving device to receive the wireless power signal transmitted from the power transmitter,   the propagation path estimation unit estimates first propagation path information characterizing a propagation path between the plurality of first antennas and the second antenna, based on the propagation path estimation signal transmitted by the second antenna from the power receiving device, and   the weight calculator calculates the weight vector so that a power transmission beam at a position of the moving body becomes a null and transmission of wireless power to the power receiving device is performed.   
     
     
         19 . A method for performing electronic 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 power transmission device 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.   
     
     
         20 . The method according to  claim 19 , wherein
 the power transmission device controls an amplitude and a phase of the wireless power signal inputted to each of the plurality of first antennas, based on the first propagation path information.