Power supply device and power supply method

Abstract

To provide an antenna device which can stably supply power.SOLUTION: An antenna device comprises: an adjustment unit which adjusts a phase of a power transmission signal supplied to a plurality of antenna elements in a first axial direction; an image acquisition unit which acquires an image; a derivation unit which converts a first position of a marker included in the image with respect to the image acquisition unit into a second position on polar coordinates on a first plane including a first axis and a second axis; an acquisition unit which acquires an elevation angle with respect to a third axis in a second plane of the position at which the first position is projected onto the second plane including the first axis and the third axis on the basis of the second position; a storage unit which stores plural sets of phase data adjusted such that phases received from the plurality of antenna elements are aligned according to the plurality of elevation angles; and a control unit which controls the adjustment unit such that the direction of a beam becomes the elevation angle in the second plane on the basis of the phase data read out according to the acquired elevation angle. The phase adjustment unit is caused to adjust the phase of the power transmission signal according to timing of performing power ramping of an envelope signal.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a power supply device and a power supply method. [Background technology]

[0002] A conventional wireless power transmitting device has been known, which includes a beam transmitting unit that transmits an energy beam for power supply to a wireless power receiving device mounted on an aircraft, an information acquiring unit that acquires control information for increasing the power receiving efficiency of the wireless power receiving device, and a control unit that controls the energy beam based on the control information so as to increase the power receiving efficiency of the wireless power receiving device.It is also described that an array antenna may be used as a power transmitting antenna (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-135900 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when adjusting the phase of the transmission signal transmitted from multiple antenna elements to align the receiving potential phase, if the phase is changed while maintaining the transmission power, discontinuities may occur in the phase change, resulting in the generation of undesirable signals such as high-frequency components, making stable power transmission difficult.

[0005] Therefore, an object of the present invention is to provide a power supply device and a power supply method that can stably transmit power when the phases of power transmission signals transmitted from a plurality of antenna elements are adjusted to align the received potential phases. [Means for solving the problem]

[0006] An antenna device according to an embodiment of the present invention includes an array antenna having a plurality of antenna elements arranged two-dimensionally along a first axis and a second axis; a phase adjustment unit that adjusts the phase of a power transmission signal supplied to the plurality of antenna elements in the first axis direction; an image acquisition unit that acquires an image through a fisheye lens; a position derivation unit that converts a first position of a marker included in an image acquired by the image acquisition unit relative to the image acquisition unit into a second position in polar coordinates on a first plane including the first axis and the second axis; and a position derivation unit that converts, based on the second position, a projection position of the first position onto a second plane including the first axis and a third axis. The power transmission signal transmission system includes an elevation angle acquisition unit that acquires an elevation angle relative to the third axis within the second plane, a control unit that controls the phase adjustment unit so that the direction of the beam emitted by the array antenna becomes the elevation angle within the second plane, a carrier wave output unit that outputs a carrier wave, a power ramping unit that outputs an envelope signal representing the amplitude of the power transmission signal and performs power ramping of the envelope signal, and a modulator that multiplies the carrier wave by the envelope signal and outputs the power transmission signal, and the power ramping unit causes the phase adjustment unit to adjust the phase of the power transmission signal according to the timing of power ramping of the envelope signal. [Effects of the Invention]

[0007] It is possible to provide a power feeding device and a power feeding method that can stably transmit power when the phases of power transmission signals transmitted from a plurality of antenna elements are adjusted to align the received potential phases. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a power supply device 100 according to an embodiment. [Figure 2] 1 is a diagram illustrating a power supply device 100 according to an embodiment. [Figure 3] FIG. 2 is a diagram showing a polar coordinate system of the array antenna 110. [Figure 4] FIG. 10 is a diagram illustrating how to obtain phase data. [Figure 5] 3 is a diagram illustrating the antenna gain of the power supply device 100. FIG. [Figure 6]10 is a diagram illustrating a difference in the amount of adjustment of phase data depending on the position of the antenna element 111. FIG. [Figure 7] 10 is a diagram illustrating a difference in the amount of adjustment of phase data depending on the position of the antenna element 111. FIG. [Figure 8] FIG. 10 is a diagram illustrating a phase discontinuity. [Figure 9] 1 is a diagram showing a portion of the power supply device 100 relating to power ramping. FIG. [Figure 10] FIG. 2 is a diagram showing an example of the configuration of a power ramping section 130A. [Figure 11] 3A to 3C are diagrams illustrating examples of waveforms of a control timing signal, a power ramping timing signal, and a phase adjustment timing signal. [Figure 12] FIG. 10 is a diagram showing power ramping coefficients represented by coefficient data arranged in time series. [Figure 13] 3A to 3C are diagrams illustrating an example of the operation of the power supply device 100. [Figure 14] FIG. 10 is a diagram showing a portion related to power ramping of a power supply device 100M according to a modified example of the embodiment. [Figure 15] FIG. 10 is a diagram illustrating an example of the configuration of a power ramping unit 130A of a power supply device 100M according to a modified example of the embodiment. [Figure 16] 10A and 10B are diagrams illustrating an example of waveforms of a power ramping timing signal and a phase adjustment timing signal. [Figure 17] 10A and 10B are diagrams illustrating an example of the operation of the power supply device 100M. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment to which a power supply device and a power supply method of the present invention are applied will be described.

[0010] <Embodiment> Fig. 1 is a diagram showing a power supply device 100 according to an embodiment. The power supply device 100 includes an array antenna 110, a phase shifter 120, a power transmission signal generation unit 130, a camera 140, and a control device 150. Note that Fig. 1 shows a simplified configuration of the periphery of the phase shifter 120. Details of the periphery of the phase shifter 120 will be described later with reference to Fig. 9.

[0011] The following explanation will be given using the XYZ coordinate system. Planar view refers to XY planar view. The X axis is an example of the first axis, the Y axis is an example of the second axis, and the Z axis is an example of the third axis. The XY plane is an example of the first plane, and the XZ plane is an example of the second plane.

[0012] The array antenna 110 is divided into, for example, N subarrays 110A. The N subarrays 110A are numbered from 1 (#1) to N (#N). #1 to #N represent the coordinates of the N subarrays 110A in the X-axis direction. Here, N is an integer equal to or greater than 2, but FIG. 1 shows an example in which N is an even number equal to or greater than 4. The N subarrays 110A are arranged in the X-axis direction (first axis direction), and each subarray 110A includes, for example, four antenna elements 111. Therefore, the array antenna 110 includes, for example, 4N antenna elements 111. Each array antenna 110 extends in the Y-axis direction (second axis direction). The antenna elements 111 are patch antennas that are rectangular in plan view. The array antenna 110 may have a ground plate maintained at ground potential on the -Z-axis side of the antenna elements 111. As an example, the center of the positions of the 4N antenna elements 111 coincides with the origin of the XYZ coordinate system. The number of antenna elements 111 included in each subarray 110A only needs to be two or more, and they only need to be arranged two-dimensionally.

[0013] The following description will be made using FIG. 2 in addition to FIG. 1. FIG. 2 is a diagram illustrating a power supply device 100 according to an embodiment. Similarly to FIG. 1, FIG. 2 also illustrates a simplified configuration of the phase shifter 120 and its surroundings. In FIG. 2, the origin of the XYZ coordinate system is shifted for clarity. However, the following description will be made assuming that the origin of the XYZ coordinate system coincides with the center of the positions of the 4N antenna elements 111, as shown in FIG. 1. For each subarray 110A, FIG. 2 also illustrates one antenna element 111 adjacent to the negative Y-axis side of the X-axis. FIG. 2 also illustrates components included in the control device 150, a marker 50A, and a power receiving device 50B. The marker 50A and the power receiving device 50B are fixed to an inner wall 51 of a tunnel, as an example. The inner wall 51 of the tunnel is an example of a wall, and the interior of the tunnel is an example of a space in which the marker 50A arranged along the inner wall 51 is present. As an example, the power supply device 100 is mounted on a work vehicle and travels through a tunnel, detects a marker 50A attached to an inner wall 51 of the tunnel, and transmits power to a power receiving device 50B.

[0014] 2, marker 50A is located at an angle θb from the Z axis when viewed on the XZ plane. For ease of explanation, the XYZ coordinate system is shifted in FIG. 2, but because the origin of the XYZ coordinate system coincides with the center of the positions of 4N antenna elements 111, angle θb is the angle between the Z axis and a line connecting the origin of the XYZ coordinate system and marker 50A in the XZ plane. When viewing the XZ plane from the +Y axis direction, angle θb is indicated as a positive value when deflected toward the +X axis direction, and as a negative value when deflected toward the -X axis direction.

[0015] N phase shifters 120 are provided corresponding to the N subarrays 110A, and the N phase shifters 120 are connected to the antenna elements 111 of the N subarrays 110A, respectively. The phase shifters 120 are an example of a phase adjustment unit that adjusts the phase, and are also an example of a phase shifter. In each subarray 110A, four antenna elements 111 are connected in parallel to one phase shifter 120.

[0016] In each subarray 110A, a transmission signal of the same phase is supplied to the four antenna elements 111. The phases of the transmission signals output from the N phase shifters 120 to the N subarrays 110A are different from one another. This makes it possible to control the angle (elevation angle) of the beam formed by the radio waves radiated from the 4N antenna elements 111 within the XZ plane.

[0017] The beam formed by the radio waves radiated from the 4N antenna elements 111 is synonymous with the beam output by the array antenna 110. In addition, the beam output by the array antenna 110 is synonymous with the beam output by the power feeding device 100.

[0018] The power transmission signal generation unit 130 is connected to the N phase shifters 120, and generates and outputs a power transmission signal. The power transmission signal is a microwave with a predetermined power. The frequency of the microwave is, for example, a frequency in the 920 MHz band. The power transmission signal is not limited to a microwave, and may be any radio wave with a predetermined frequency. Details of the power transmission signal generation unit 130 will be described later with reference to FIGS. 9 and 10.

[0019] The camera 140 is disposed between the N / 2-th subarray 110A and the N / 2+1-th subarray 110A in the X-axis direction, and is disposed between the second and third antenna elements 111 from the +Y-axis direction side of the four antenna elements 111 included in each subarray in the Y-axis direction. The camera 140 has a fisheye lens 141 and a camera body 142. The camera 140 is an example of an image acquisition unit. In FIG. 2, the camera body 142 is shown divided into an imaging unit 142A and an image processing unit 142B.

[0020] The fisheye lens 141 is a lens that employs an equidistant projection method. For example, the center position of the fisheye lens 141 coincides with the center of the 4N antenna elements 111 and the origin of the XYZ coordinate system. The camera body 142 is the portion of the camera 140 other than the fisheye lens 141, and may be a camera including a CMOS (Complementary Metal Oxide Semiconductor) image sensor or an infrared camera.

[0021] The camera 140 acquires an image including the marker 50A through the fisheye lens 141 and outputs the image data to the control device 150. The marker 50A is attached to the power receiving device 50B, which has a power receiving antenna and is a target to be irradiated with the beam output by the power supply device 100. The power supply device 100 obtains the position of the marker 50A included in the image acquired by the camera 140, and irradiates the beam toward the power receiving device 50B.

[0022] The camera body 142 has an imaging unit 142A and an image processing unit 142B. The imaging unit 142A includes an imaging element and is a unit that acquires image data by capturing an image through the fisheye lens 141. The image processing unit 142B performs image processing such as binarization on the image data acquired by the imaging unit 142A, and outputs a pixel index to the control device 150. The pixel index is an XY coordinate value (address) that indicates the position of the marker 50A on the captured image screen.

[0023] The control device 150 has a position derivation unit 151, an elevation angle acquisition unit 152, a positional deviation detection unit 153, a distance estimation unit 154, a control unit 155, and a memory 156. The control device 150 is realized by a computer including a CPU (Central Processing Unit) and a memory. The position derivation unit 151, the elevation angle acquisition unit 152, the positional deviation detection unit 153, the distance estimation unit 154, and the control unit 155 are functional blocks representing the functions of a program executed by the control device 150. The memory 156 is a functional representation of the memory of the control device 150.

[0024] Here, the position derivation unit 151, elevation angle acquisition unit 152, position deviation detection unit 153, distance estimation unit 154, control unit 155, and memory 156 will be described using FIG. 3 in addition to FIG. 1 and FIG. 2. FIG. 3 is a diagram showing a polar coordinate system of the array antenna 110. FIG. 3 shows subarrays 110A of the array antenna 110 in the power supply device 100, antenna elements 111 included in each subarray 110A, and beams 115 output from the array antenna 110, and omits other components. FIG. 3 also shows a polar coordinate system on a plane 1 parallel to the XY plane.

[0025] Furthermore, the position of marker 50A in the XYZ coordinate system is defined as P1, and the elevation angle of the line segment connecting origin O and position P1 is defined as θ, and the azimuth angle is defined as φ. The elevation angle is the angle with respect to the +Z axis direction, and the azimuth angle is the angle with respect to the +X axis direction, with a clockwise direction being a positive value in a planar view seen from the +Z axis direction. Furthermore, the elevation angle of the line segment connecting position P1a, which is a projection of position P1 onto the XZ plane, and origin O is defined as θa. Elevation angle θa is an angle obtained approximately by projecting elevation angle θ onto the XZ plane when the position of marker 50A is close to the XZ plane. Like angle θb, elevation angle θa indicates a positive value when tilted toward the +X axis direction when viewed from the +Y axis direction of the XZ plane, and a negative value when tilted toward the -X axis direction.

[0026] The position P1 is an example of a first position, the position P1a is an example of a projection position, and the origin O is an example of a reference point of an XYZ coordinate system.

[0027] The power feeding device 100 controls the elevation angle of the beam 115 output by the array antenna 110 only within the XZ plane. This is based on the assumption that because the array antenna 110 performs in-phase power feeding in the Y-axis direction, the beam is fixed in the Y-axis direction and can be swung in an elevation angle direction with the Z-axis at 0 degrees, and that the position of the power receiving device 50B does not deviate much from the XZ plane (for example, within approximately ±30 degrees in elevation angle relative to the Z-axis in the YZ plane). If the power receiving device 50B is located in such a position, simply controlling the elevation angle of the beam 115 within the XZ plane allows the power receiving device 50B to be efficiently irradiated with the beam 115 while keeping the size of the control unit of the array antenna 110 small.

[0028] The position derivation unit 151 calculates the center of gravity of the image of the marker based on the pixel index output from the image processing unit 142B. The pixel index output from the image processing unit 142B represents an equidistant projection image obtained through the fisheye lens 141. By this image processing, the position P1 of the marker relative to the array antenna 110, which is included in the image acquired by the camera 140, is converted into a position P2 in polar coordinates on the XY plane. In this way, the position derivation unit 151 derives the position P2. The position P1 is the position of the center of gravity calculated by the position derivation unit 151. The position P2 is an example of a second position.

[0029] The position P2 is expressed by the radius vector r and the deflection angle φ from the origin O. The radius vector r is expressed by the focal length of the fisheye lens 141 as f L Then, r=f L The position P2 is represented by θ. The deflection angle φ is the same as the azimuth angle φ. The position derivation unit 151 obtains r·cosφ by mapping the radius vector r onto the X axis through the image processing described above. The position derivation unit 151 outputs data representing the position P2 to the elevation angle acquisition unit 152.

[0030] The elevation angle acquisition unit 152 calculates the X coordinate (r·cosφ) of the mapping position P2a obtained by mapping the position P2 onto the X axis using the focal length f of the fisheye lens 141. L The value divided by (r cosφ / f L) is acquired (calculated) as the elevation angle θa. The reason why the elevation angle θa can be acquired in this manner will be described later. The elevation angle acquisition unit 152 outputs the elevation angle θa to the distance estimation unit 154 and the control unit 155.

[0031] The misalignment detection unit 153 determines the shape and center of gravity of the marker 50A based on the pixel index output from the image processing unit 142B, and detects the misalignment between the camera 140 and the marker 50A in the Y-axis direction based on the position of the center of gravity within the range in which the marker 50A exists. For example, the center of the fisheye lens 141 coincides with the center of the 4N antenna elements 111 and the origin of the XYZ coordinate system. Therefore, for example, the position of the center of gravity in the Y-axis direction when there is no misalignment between the camera 140 and the marker 50A can be set to Y = 0. If the determined position of the center of gravity in the Y-axis direction within the range in which the marker 50A exists is Y = 0, the misalignment detection unit 153 determines that there is no misalignment between the camera 140 and the marker 50A. Furthermore, if the determined position of the center of gravity in the Y-axis direction within the range in which the marker 50A exists is not Y = 0, the misalignment detection unit 153 determines that there is a misalignment between the camera 140 and the marker 50A, and detects the misalignment. The position shift detection unit 153 outputs the detection result to the distance estimation unit 154. The position of the center of gravity may be acquired from the position derivation unit 151.

[0032] When the elevation angle θa calculated by the elevation angle acquisition unit 152 is zero degrees (0 degrees), the distance estimation unit 154 estimates the distance from the center of the fisheye lens 141 to the marker 50A based on the number of pixel indexes output from the image processing unit 142B of the camera 140. An elevation angle θa of 0 degrees means that the marker 50A is located in front of the fisheye lens 141 in the Z-axis direction (the center of gravity of the marker 50A is located on the Z-axis).

[0033] The distance estimation unit 154 calculates the facing distance r from the center of the fisheye lens 141 to the marker 50A when the elevation angle θa is 0 degrees. FD Estimate the opposing distance r FD is the distance when the marker 50A faces the camera 140 on the Z axis.

[0034] For example, the number of multiple binarized pixel indexes acquired by the image processing unit 142B when the camera 140 and the marker 50A are separated by multiple distances on the Z axis is stored in advance in the memory 156. Then, the distance estimation unit 154 counts the number of pixel indexes output from the image processing unit 142B of the camera 140 when the elevation angle θa is zero degrees (0 degrees), and estimates the multiple opposing distances r stored in the memory 156. FD By comparing with a plurality of reference data corresponding to the angle of elevation θa, the facing distance r from the center of the fisheye lens 141 to the marker 50A when the angle of elevation θa is 0 degrees can be calculated. FD Estimate the opposing distance r FD Since the number of pixel indices varies depending on FD can be estimated.

[0035] In addition, when the elevation angle θa is zero degrees (0 degrees), if the image processing unit 142B of the camera 140 outputs pixel indices multiple times, the facing distance r is calculated based on the average number of the multiple pixel indices. FD can be estimated.

[0036] Furthermore, since the fisheye lens 141 is used, when there is a positional deviation between the camera 140 and the marker 50A, the distance r FD Therefore, when the positional deviation detection unit 153 determines that a positional deviation occurs between the camera 140 and the marker 50A in the Y-axis direction, the distance estimation unit 154 stores in advance in the memory 156 data indicating the degree of change in the pixel index number with respect to the positional deviation in the Y-axis direction, and calculates the facing distance r using the pixel index number corrected according to the degree of positional deviation in the Y-axis direction. FD can be estimated.

[0037] The control unit 155 controls the amount of phase shift (adjustment amount) in the phase shifter 120 so that the direction of the beam 115 radiated by the array antenna 110 has an elevation angle θa in the XZ plane. The elevation angle θa is acquired by the elevation angle acquisition unit 152. The control unit 155 also controls the output of the power transmission signal generation unit 130, controls the shooting of the camera 140, etc.

[0038] Specifically, the control unit 155 controls the amount of phase shift in the phase shifter 120 as follows. FD and the elevation angle θa acquired by the elevation angle acquisition unit 152, and reads out from the memory 156 phase data corresponding to the elevation angle θa, and controls the amount of phase shift in the N phase shifters 120 based on the read out phase data.

[0039] Here, in order for the antenna of the power receiving device 50B to efficiently receive power, it is ideal that the phases of the power transmission signals when the antenna of the power receiving device 50B receives power from the N subarrays 110A are the same. Meanwhile, the power feeding device 100 transmits a power transmission signal to the power receiving device 50B that is located at a short distance, for example, about 3 to 7 m, from the array antenna 110. When transmitting power to the power receiving device 50B that is attached to the inner wall 51 of a tunnel, the distance from the array antenna 110 to the power receiving device 50B when the angle θb is 0 degrees is about 3 to 5 m.

[0040] Since power transmission over such a short distance is assumed, the relative difference in distance from each of the N subarrays 110A to the antenna of the power receiving device 50B is relatively large, and when the N subarrays 110A transmit power to the same target, the phases of the power transmission signals received by the antenna of the power receiving device 50B from the N subarrays 110A will not be aligned, preventing the power receiving device 50B from receiving power efficiently. The difference in distance from each of the N subarrays 110A to the antenna of the power receiving device 50B varies depending on the angle θb and the distance in the Z-axis direction from the N subarrays 110A to the antenna of the power receiving device 50B.

[0041] Therefore, the power feeding device 100 uses phase data for adjusting the phase of each of the N subarrays 110A when transmitting power so that the phases of the power transmission signals received by the antenna of the power receiving device 50B from the N subarrays 110A are aligned. The phase data represents the amount of phase shift (adjustment amount). As an example, assuming that power transmission is performed when the elevation angle θa changes from +70 degrees to -70 degrees as the power feeding device 100 moves, multiple sets of phase data are prepared that can adjust the amount of phase shift of the N subarrays 110A in increments of 1 degree. Each piece of phase data includes N phase shift amounts to be set in the N phase shifters 120 connected to the N subarrays 110A, respectively, corresponding to a certain elevation angle θa. 141 sets of such phase data are prepared in increments of 1 degree for the elevation angle θa in the range from +70 degrees to -70 degrees, and are used to calculate a phase data set for a certain facing distance r FD The phase data are multiple sets of data for multiple opposing distances r FD In order to adjust the phase shift amount of the N subarrays 110A according to each of the plurality of opposing distances r FD . Since the phase data is data created based on the angle θb, multiple sets of phase data ψ3(θb) to ψ7(θb) are shown using θb in FIG. 2. The control unit 155 may use multiple sets of phase data for the angle θb equal to the elevation angle θa. Each of the phase data ψ3(θb) to ψ7(θb) has shift amounts θs#1 to θs#N corresponding to the coordinates (#1 to #N) of the N subarrays 110A. For example, of the shift amounts θs#1 to θs#N included in the phase data ψ3(θb), the shift amount θs#1 is used for the antenna element 111 of the subarray 110A at coordinate #1, and the shift amount θs#N is used for the antenna element 111 of the subarray 110A at coordinate #N. In the following, when the shift amounts θs#1 to θs#N are not distinguished from one another, they will be referred to as the shift amount θs.

[0042] The control unit 155 calculates the facing distance r estimated by the distance estimation unit 154. FDThe phase shift amount in the N phase shifters 120 is controlled by using phase data for an angle θb that is equal to the elevation angle θa acquired by the elevation angle acquisition unit 152 from among the multiple sets of phase data, using multiple sets of phase data corresponding to the angle θb.

[0043] The memory 156 stores the programs executed when the position derivation unit 151, the elevation angle acquisition unit 152, and the control unit 155 perform processing, data used in conjunction with the execution of the programs, data generated by the execution of the programs, image data acquired by the camera 140, etc. The memory 156 also stores a plurality of opposing distances r FD For each of these, multiple sets of phase data are stored. For example, five opposing distances r FD For the elevation angle θa, 141 sets of phase data are stored in 1 degree increments for a range from +70 degrees to -70 degrees.

[0044] Next, a method for determining the elevation angle θa will be described.

[0045] The elevation angle θa can be calculated from the geometric relationship between the position P1 and the position P1a using the azimuth angle φ and the elevation angle θ using the following equation (1).

[0046]

number

[0047]

number

[0048]

number

[0049] As described above, the focal length of the fisheye lens 141 is f L Then, the radius vector r is expressed by the following equation (4).

[0050]

number

[0051]

number

[0052] Next, a method for obtaining phase data will be described. Fig. 4 is a diagram for explaining the method for obtaining phase data. Fig. 4 shows a fisheye lens 141 of a camera 140, a marker 50A, a power receiving device 50B, and N antenna elements 111. Each antenna element 111 is one of four antenna elements 111 included in N subarrays 110A. The position of the marker 50A is the same as the position of the power receiving device 50B.

[0053] As shown in FIG. 4, the distances from the N subarrays 110A to the marker 50A are set to r1 to rN. Here, for simplicity of explanation, it is assumed that there is no positional deviation between the camera 140 and the marker 50A in the Y-axis direction. Since the centers of the 4N antenna elements 111 coincide with the origin of the XYZ coordinate system, the coordinates of the centers of the 4N antenna elements 111 are (X, Y, Z) = (0, 0, 0). Furthermore, there is no positional deviation between the camera 140 and the marker 50A in the Y-axis direction, and the facing distance is r FD Since the angle of the power receiving device 50B as viewed from the fisheye lens 141 is θb, the position of the power receiving device 50B is expressed as (X, Y, Z)=(r FD ·tanθb,0,r FD) where the distance from the fisheye lens 141 to the power receiving device 50B is r ref Then, the distance r ref can be expressed by the following equation (6).

[0054]

number

[0055] The position of the i-th antenna element 111 among the N antenna elements 111 is (X, Y, Z)=(d i , 0, 0), the distance r from the i-th antenna element 111 to the power receiving device 50B is i can be expressed by the following equation (7).

[0056]

number

[0057] Therefore, the distance r from the fisheye lens 141 to the power receiving device 50B is ref and the path difference τ between the distance ri from the i-th antenna element 111 to the power receiving device 50B. i can be expressed by the following equation (8).

[0058]

number

[0059] Path difference τ i Since the unit is meters, it can be converted to the wavelength λ of the microwave used to obtain the phase difference ψ i When calculated, it can be expressed as the following equation (9).

[0060]

number

[0061] -ψr, which is the phase difference expressed by Equation (9) with the opposite sign FDi(θb) is set as the phase to be set in the phase shifter 120 when the i-th antenna element 111 transmits power, and multiple sets of phase data corresponding to multiple elevation angles θa for the N subarrays 110A are prepared and stored in the memory 156. In addition, multiple opposing distances r FD A plurality of sets of phase data for the angles θb can be prepared and stored in the memory 156. By using such a plurality of sets of phase data, it is possible to make the power transmission signals transmitted from the N subarrays 110A arrive at the power receiving device 50B in the same phase. The plurality of sets of phase data corresponding to the plurality of angles θb are expressed by the following equation (10).

[0062]

number

[0063] The control unit 155 may use the phase data of the angle θb corresponding to the elevation angle θa to set the shift amounts in the N phase shifters 120 connected to the N subarrays 110A, respectively.

[0064] 5 is a diagram illustrating the effect of the power supply device 100. FD 10 is a diagram showing the antenna gain of power received by the antenna of power receiving device 50B when the distance is 4 m and the speed of a vehicle equipped with power supply device 100 is 80 km / h. The horizontal axis represents time, with 0 seconds representing the time when elevation angle θa becomes 0 degrees, −300 milliseconds representing the time when elevation angle θa becomes +60 degrees, and +300 milliseconds representing the time when elevation angle θa becomes −60 degrees. In other words, the time on the horizontal axis corresponds to elevation angle θa.

[0065] 5, the solid line indicates the antenna gain when the power feeding device 100 adjusts the shift amount in the phase shifter 120 using phase data based on the facing distance and the elevation angle, and the dashed line indicates the antenna gain when phase data based only on the elevation angle is used for comparison. The antenna gain when phase data based only on the elevation angle is the antenna gain obtained in the power receiving device 50B when the shift amounts in the N phase shifters 120 connected to the N subarrays 110A are set to values ​​corresponding to the elevation angle θa.

[0066] 5, the antenna gain when using phase data based on the facing distance and elevation angle was larger than or equal to the antenna gain when using phase data based only on the elevation angle, and the closer to 0 seconds the time period was (the smaller the absolute value of the elevation angle θa), the larger the difference between the antenna gain when using phase data based on the facing distance and elevation angle and the antenna gain when using phase data based only on the elevation angle. It is considered that the closer the elevation angle θa was to 0 degrees, the shorter the distance between the N subarrays 110A and the power receiving device 50B, and the more pronounced the effect of individual phase control of the N subarrays 110A using phase data based on the facing distance and elevation angle became.

[0067] <Difference in the amount of phase data adjustment depending on the position of the antenna element 111> 6 and 7 are diagrams illustrating differences in the amount of phase data adjustment depending on the position of the antenna element 111. Here, as an example, the number N of subarrays 110A is 12, and FIGS. 6 and 7 show a marker 50A, a power receiving device 50B, and 12 antenna elements 111. Each antenna element 111 is one of four antenna elements 111 included in the 12 subarrays 110A. The position of the marker 50A is the same as the position of the power receiving device 50B.

[0068] The 12 antenna elements 111 included in the subarray 110A are referred to as antenna elements 111 #1 to #12 using the coordinates #1 to #12 of the subarray 110A, but antenna elements 111 #3 to #5 and #8 to #10 are not shown. Also, FIGS. 6 and 7 show the difference in distance from antenna element 111 #6, which is located in the center in the X direction among the 12 antenna elements 111, to the power receiving device 50B, and antenna element 111 #1, which is located at the end in the X direction. Here, the difference in distance from antenna elements 111 #1 and #6 to the power receiving device 50B is shown by a line connecting the fisheye lens 141 of the camera 140 to the marker 50A. In FIGS. 6 and 7, the fisheye lens 141 is not shown, and the position of the fisheye lens 141 is indicated by a leading line.

[0069] 6 and 7 show the marker 50A and the power receiving device 50B in a direction of angle θb(t) at time t, and the marker 50A and the power receiving device 50B in a direction of angle θb(t+T) at time t+T. Time T represents the control period T of the power supply device 100.

[0070] As shown in FIG. 6, when a perpendicular line is extended from the antenna element 111 of #6 to the line connecting the fisheye lens 141 and the marker 50A, the distance L from the intersection of the perpendicular line and the line connecting the fisheye lens 141 and the marker 50A to the fisheye lens 141 is i is L6(t) at time t and L6(t+T) at time t+T.

[0071] Similarly, as shown in FIG. 7, when a perpendicular line is drawn from the antenna element 111 of #1 to the line connecting the fisheye lens 141 and the marker 50A, the distance L from the intersection of the perpendicular line and the line connecting the fisheye lens 141 and the marker 50A to the fisheye lens 141 is i is L1(t) at time t and L1(t+T) at time t+T.

[0072] The distances L1(t) and L1(t+T) for antenna element 111 #1, which is located at the end in the X direction, are longer than the distances L6(t) and L6(t+T) for antenna element 111 #6, which is located in the center in the X direction, and the difference between distance L1(t) and distance L1(t+T) is greater than the difference between distance L6(t) and distance L6(t+T).

[0073] 4, the phase difference between the phase data used at time t and the phase data used at time t+T for the #1 antenna element 111 is greater than the phase difference between the phase data used at time t and the phase data used at time t+T for the #6 antenna element 111. Such a phase difference represents the amount by which the phase data changes at time t+T, and is the amount of change in the shift amount (adjustment amount) of the phase data.

[0074] That is, the change in the shift amount at time t+T of the phase data for #1, #2, #11, #12, etc., located at the ends in the X direction, is larger than the change in the shift amount at time t+T of the phase data for #5, #6, #7, #8, located at the center.

[0075] The greater the amount of change in the shift amount of the phase data at time t+T, the more likely it is that the phase will become discontinuous when the phase of the transmission signal is switched. Figure 8 is a diagram explaining the phase discontinuity. In Figure 8, the horizontal axis represents time t, and the vertical axis represents the amplitude of the transmission power of the transmission signal.

[0076] In Fig. 8, the time t s The waveform of the power transmission signal when the phase of the phase data is switched by approximately 180 degrees at time t s corresponds to time t+T in FIGS. 6 and 7, and is the time when two successive control periods T switch over. s Although the shift amount of the phase data does not change by 180 degrees in this case, the most extreme case will be explained here.

[0077] In this way, time t sIf the phase data is adjusted significantly in the power receiving device 50B, a discontinuity occurs in the phase control. Such a discontinuity generates harmonics in the transmission power of the power transmission signal, making it difficult to transmit power stably. Furthermore, the discontinuity widens the spurious components of the power transmission signal, causing interference with other devices that may be present around the power receiving device 50B.

[0078] Therefore, the power supply device 100 of the embodiment performs power ramping of the transmission signal to enable stable power transmission. Power ramping means gradually increasing or decreasing the transmission power of the transmission signal by applying a gradient to the transmission power. Furthermore, when adjusting the phase of the transmission signal, a phase shift is performed while the transmission power of the transmission signal is being decreased by power ramping. This is to suppress the generation of spurious signals such as harmonics and to achieve stable power transmission. Furthermore, this is to prevent interference with other devices that may be present around the power receiving device 50B.

[0079] <Power Transmission Signal Generator 130 and Power Ramping> Fig. 9 is a diagram showing a portion related to power ramping of power feeding device 100. Fig. 9 shows antenna elements 111 #1 to #N, phase shifter (PD) 120, power transmission signal generator 130, camera 140, elevation angle acquirer 152, and phase control units 155A #1 to #N and memory unit 156A. Phase control unit 155A is an extracted portion that performs phase control from control unit 155 shown in Fig. 2. Memory unit 156A is an extracted portion that stores phase data from memory 156 shown in Fig. 2, and is shown inside phase control unit 155A in Fig. 9.

[0080] <Power Transmission Signal Generator 130> The power transmission signal generating unit 130 includes a power ramping unit 130A, a carrier wave output unit 130B, a modulator 130C, and a BPF (Band Pass Filter) 130D.

[0081] The power ramping unit 130A outputs an envelope signal representing the amplitude of the power transmission signal to the modulator 130C and performs power ramping of the envelope signal. The power ramping unit 130A has coefficient data representing power ramping coefficients. The power ramping unit 130A also outputs a control timing signal representing the control timing of the camera 140 and a phase adjustment timing signal that causes the phase shifter 120 to adjust the phase of the power transmission signal. Details of the power ramping unit 130A will be described later with reference to FIG. 10.

[0082] The carrier wave output unit 130B outputs a carrier wave, which is the source of the power transmission signal, to the modulator 130C. The frequency of the carrier wave is equal to the frequency of the power transmission signal. The carrier wave is a microwave.

[0083] The modulator 130C generates a transmission signal by multiplying the envelope signal output from the power ramping unit 130A by the carrier wave output from the carrier wave output unit 130B. The modulator 130C outputs the transmission signal up-converted by the multiplication to the BPF 130D.

[0084] BPF 130D has a passband for removing noise components and the like from the power transmission signal input from modulator 130C, and removes the noise components and the like from the power transmission signal and outputs the signal to phase shifters 120 #1 to #N.

[0085] <Phase Control Unit 155A and Memory Unit 156A> The phase control units 155A #1 to #N perform phase control in the phase shifters 120 #1 to #N. The memory units 156A #1 to #N store the shift amount (one of θs#1 to θs#N) corresponding to the coordinates (#1 to #N) of the antenna element 111 from each of multiple sets of phase data ψ3(θb) to ψ7(θb).

[0086] For example, the memory unit 156A of the antenna element 111 at coordinate #1 stores a shift amount θs#1 of each of the phase data ψ3(θb) to ψ7(θb) corresponding to the coordinate #1 of the antenna element 111. The memory unit 156A of the antenna element 111 at coordinate #N stores a shift amount θs#N of each of the phase data ψ3(θb) to ψ7(θb) corresponding to the coordinate #N of the antenna element 111.

[0087] The phase control sections 155A of #1 to #N respectively determine the angle θb and the facing distance r FD and the coordinates of the sub-array 110A (one of #1 to #12), the shift amount (one of θs#1 to θs#12) is read out from the memory unit 156A and output. FD is 3 m, the phase control unit 155A of the antenna element 111 at coordinate #1 reads out and outputs the shift amount θs#1 for 3 m corresponding to the angle θb, and the phase control unit 155A of the antenna element 111 at coordinate #N reads out and outputs the shift amount θs#N for 3 m corresponding to the angle θb.

[0088] Here, a description will be given of a mode in which the shift amount (one of θs#1 to θs#12) is stored in memory units 156A #1 to #N. However, phase control unit 155A may calculate and determine the shift amount (one of θs#1 to θs#12) according to the coordinates (#1 to #N) of antenna element 111. In this case, memory unit 156A is not necessary.

[0089] <Power ramping section 130A> 10 is a diagram showing an example of the configuration of power ramping section 130A. Power ramping section 130A has power ramping timing signal generation section 131, phase adjustment timing signal generation section 132, control timing signal generation section 133, coefficient memory 134, and selector 135. Power ramping timing signal generation section 131 is an example of a first timing signal generation section. Phase adjustment timing signal generation section 132 is an example of a second timing signal generation section. Control timing signal generation section 133 is an example of a third timing signal generation section. Coefficient memory 134 is an example of a storage section. Selector 135 is an example of an output section. Power ramping section 130A can be realized, for example, by an FPGA (Field-Programmable Gate Array).

[0090] Power ramping timing signal generator 131 generates a power ramping timing signal that indicates the timing for power ramping of the envelope signal and whether or not to perform power ramping, and outputs the generated signal to phase adjustment timing signal generator 132, coefficient memory 134, and selector 135. An H (High) level power ramping timing signal indicates that power ramping is to be performed, and an L (Low) level power ramping signal indicates that power ramping is not to be performed. The timing at which the power ramping timing signal switches from L level to H level indicates the timing at which power ramping starts, and the timing at which the power ramping timing signal switches from H level to L level indicates the timing at which power ramping ends and the system enters a non-execution state.

[0091] Based on the power ramping timing signal generated by the power ramping timing signal generation unit 131, the phase adjustment timing signal generation unit 132 generates a phase adjustment timing signal that causes the phase shifter 120 to adjust the phase of the power transmission signal, and outputs the signal to the phase shifters 120 #1 to #N. The phase adjustment timing signal is a signal obtained by delaying the power ramping timing signal by a predetermined time. Details of this will be described later.

[0092] Control timing signal generator 133 generates a control timing signal that indicates the control timing of camera 140, and outputs it to power ramping timing signal generator 131 and camera 140. The control timing signal is a signal that indicates the control timing of camera 140, and is also a signal that serves as the basis for the power ramping timing signal and the phase adjustment timing signal. Details of this will be described later using FIG. 11.

[0093] Coefficient memory 134 stores coefficient data representing power ramping coefficients, and outputs the coefficient data to one of two input terminals of selector 135 (the lower terminal of the two terminals with two arrows pointing from the left in FIG. 10) in response to a power ramping timing signal. The coefficient data has a plurality of coefficients arranged so that their values ​​change every predetermined unit time. For example, the coefficients have a plurality of coefficients arranged so that their values ​​change every time interval of at least several tens of megahertz.

[0094] Selector 135 has an input terminal (the lower terminal of the two terminals with two arrows entering from the left in FIG. 10) connected to coefficient memory 134, and an input terminal (the upper terminal of the two terminals with two arrows entering from the left in FIG. 10) to which fixed data with a power ramping coefficient of 1 is input. Selector 135 also has a terminal (the lower terminal in FIG. 10) connected to power ramping timing signal generator 131 to which a power ramping timing signal is input as a selection signal, and an output terminal (the right terminal in FIG. 10) that outputs an envelope signal.

[0095] When the power ramping timing signal is at L level, selector 135 selects and outputs the fixed value 1 of the two power ramping coefficients input to its two input terminals. When the power ramping signal switches from L level to H level, selector 135 starts power ramping, and while the power ramping signal is at H level, selector 135 outputs the power ramping coefficient input from coefficient memory 134 in accordance with the passage of time.

[0096] <Three timing signals> FIG. 11 is a diagram showing an example of waveforms of the control timing signal, the power ramping timing signal, and the phase adjustment timing signal.

[0097] The control timing signal is, for example, a pulse signal that alternates between H level and L level at equal intervals. When the control timing signal rises to H level, the camera 140 captures an image.

[0098] The power ramping timing signal is a pulsed signal that delays the control timing signal by time t1 and alternately repeats an H-level period ΔTu, an H-level period ΔTd+ΔTu, and an H-level period ΔTd. The period ΔTu is a ramp-up period for increasing the power ramping coefficient, and the period ΔTd is a ramp-down period for decreasing the power ramping coefficient. ΔTu and ΔTd are equal. Time t1 is a circuit delay adjustment width from when the control timing signal generator 133 outputs the control timing signal to when it is transmitted to the camera 140. The time t1 is used to adjust the timing of power ramping and when the camera 140 captures an image. The periods ΔTu and ΔTd will be described later with reference to FIG. 12.

[0099] The phase adjustment timing signal is a signal obtained by delaying the control timing signal by time t1+t2. The phase shifter 120 adjusts the phase at the timing when the phase adjustment timing signal rises to an H level. Time t2 is a circuit delay adjustment width that adjusts the circuit delay from when the power ramping timing signal generation unit 131 outputs the power ramping timing signal until the power transmission signal reaches the phase shifter 120, and is particularly the time for adjusting the delay occurring in the BPF 130D. When performing power ramping, adjustment is made at time t2 to match the timing at which the power transmission signal and the phase adjustment timing signal reach the phase shifter 120.

[0100] 11, power ramping is performed by the power ramping timing signal shown in Fig. 11, and the amplitude of the power transmission signal supplied to phase shifter 120 becomes zero when time t2 has elapsed since the start of period ΔTu of the power ramping timing signal shown in Fig. 11, which is the same as the timing at which the phase adjustment timing signal rises to H level. The timing at which the phase adjustment timing signal rises to H level is the timing at which phase shifter 120 adjusts the phase. By delaying the phase adjustment timing signal by time t2 with respect to the power ramping timing signal in this way, phase shifter 120 adjusts the phase at the timing at which the amplitude of the power transmission signal becomes zero due to power ramping.

[0101] <Power ramping coefficient> FIG. 12 is a diagram showing a time series arrangement of power ramping coefficients represented by coefficient data. The horizontal axis is the time axis, and is represented by the number of 512 sample points. The interval between adjacent sample points is a predetermined unit time during which the coefficient data changes. The vertical axis represents the power ramping coefficient. The 512 pieces of data shown in FIG. 12 represent the envelope signal output by selector 135. The signal level of the envelope signal is the power ramping coefficient.

[0102] 12, power ramping coefficients 0 to 31 are power ramping coefficients for a ramp-up period that continuously increases from 0 to 1 during a period ΔTu when the power ramping timing signal shown in Fig. 11 is at H level. Selector 135 outputs a ramp-up envelope signal during period ΔTu.

[0103] The power ramping coefficients from 32 to 223 are power ramping coefficients that are fixed to 1 during the period when the power ramping timing signal shown in Fig. 11 is at L level. When the power ramping timing signal is at L level, selector 135 outputs a fixed value of 1, so the amplitude (power ramping coefficient) of the envelope signal is fixed to 1.

[0104] The power ramping coefficients from 224 to 255 are power ramping coefficients for a ramp-down period that continuously decreases from 1 to 0 during a period ΔTd when the power ramping timing signal shown in Fig. 11 is at H level. Selector 135 outputs an envelope signal that ramps down during period ΔTd.

[0105] The power ramping coefficients from 256 to 287 are power ramping coefficients for a ramp-up period that continuously increases from 0 to 1 during a period ΔTu when the power ramping timing signal shown in Fig. 11 is at H level. Selector 135 outputs an envelope signal that ramps up during period ΔTu.

[0106] The power ramping coefficients 288 to 479 are power ramping coefficients that are fixed to 1 during the period when the power ramping timing signal shown in Fig. 11 is at L level. When the power ramping timing signal is at L level, selector 135 outputs a fixed value of 1, so the amplitude (power ramping coefficient) of the envelope signal is fixed to 1.

[0107] The power ramping coefficients from 480 to 512 are power ramping coefficients for a ramp-down period that continuously decreases from 1 to 0 during a period ΔTd when the power ramping timing signal shown in Fig. 11 is at the H level. Selector 135 outputs an envelope signal that ramps down during period ΔTd.

[0108] As described above, at the start of the ramp-up period ΔTu, the power ramping coefficient becomes 0, and therefore the amplitude of the power transmission signal also becomes zero (0).

[0109] 12 and outputs a fixed value of 1 when power ramping is not performed, the coefficient data stored in coefficient memory 134 may be data in which power ramping coefficients 0 to 31, 224 to 255, 256 to 287, and 480 to 512 are stored in association with the timing of sample points. Note that the coefficient data may also be data in which power ramping coefficients 0 to 31 and 224 to 255 are stored in association with the timing of sample points.

[0110] For example, a raised cosine time response can be used for the coefficient data. Here, if α (0<α<1) is a roll-off coefficient, the coefficient data is expressed by the following equation (11).

[0111]

number

[0112] The coefficient data is data representing a power ramping coefficient that changes the transmission power of the transmission signal during a ramp-down period in which the value continuously decreases over a period ΔTd and during a ramp-up period in which the value continuously increases over a period ΔTu.

[0113] The power ramping coefficients are coefficients whose values ​​change continuously over time within the range of 0 to 1. A continuously changing value means that all power ramping coefficients lie on a continuous curve.

[0114] <Operation of Power Supply Device 100> FIG. 13 is a diagram illustrating an example of the operation of the power supply device 100. FIG. 13 shows a control timing signal, a power transmission signal output from the modulator 130C, and a power transmission signal input to the phase shifter 120. The power transmission signal output from the modulator 130C has its amplitude reduced to zero by power ramping at the timing when the control timing signal rises to an H level. The power transmission signal input to the phase shifter 120 is delayed by time t1+t2 with respect to the power transmission signal output from the modulator 130C. As shown in FIG. 11, a phase adjustment timing signal delayed by time t1+t2 with respect to the control timing signal is input to the phase shifter 120, and therefore the timing is synchronized with the power transmission signal (input to the phase shifter 120) shown in FIG. 13. Therefore, the phase shifter 120 can adjust the phase at the timing when the intensity of the power transmission signal supplied to the phase shifter 120 becomes zero by power ramping, thereby preventing discontinuities from occurring when the phase shifter 120 shifts the phase of the power transmission signal. As a result, it is possible to suppress the spread of spurious signals in the power transmission signal, and reduce interference with other devices that may be present around the power receiving device 50B.

[0115] <Effects> The power supply device 100 includes an array antenna 110 having a plurality of antenna elements 111 arranged two-dimensionally along the X-axis and the Y-axis, a phase shifter 120 that adjusts the phase of a power transmission signal supplied to the plurality of antenna elements 111 in the X-axis direction, a camera 140 that acquires an image through a fisheye lens 141, a position derivation unit 151 that converts a position P1 of a marker 50A included in an image acquired by the camera 140 with respect to the camera 140 into a position P2 in polar coordinates on a first plane including the X-axis and the Y-axis, and a position derivation unit 151 that converts, based on the position P2, a position P2 in the XZ plane of a projection position obtained by projecting the position P1 onto the XZ plane including the X-axis and the Z-axis. the power transmission signal by multiplying the carrier wave by the envelope signal, and outputs the power transmission signal. The power ramping unit 130A causes the phase shifter 120 to adjust the phase of the power transmission signal according to the timing of power ramping of the envelope signal. Therefore, when adjusting the phase of the power transmission signal, the occurrence of discontinuities is suppressed, and spurious signals such as harmonics are suppressed, thereby achieving stable power transmission.

[0116] Therefore, it is possible to provide a power feeding device 100 and a power feeding method that enable stable power transmission when adjusting the phases of power transmission signals transmitted from the plurality of antenna elements 111 to align the received potential phases. Furthermore, since the modulator 130C multiplies the carrier wave output from the carrier wave output unit 130B by the envelope signal output from the power ramping unit 130A to output the power transmission signal, it is possible to provide a power feeding device 100 that achieves both a compact circuit scale and power ramping of the transmission signal. Furthermore, it is possible to suppress interference with other devices that may be present around the power receiving device 50B.

[0117] In addition, multiple sets of phase data are used for multiple opposing distances r FD are stored in the memory 156, and the distance estimation unit 154 calculates the facing distance rFD Therefore, the facing distance r FD It is possible to set the shift amounts in the N phase shifters 120 connected to the N subarrays 110A, respectively, by using a plurality of sets of phase data corresponding to the distance to the power receiving device 50B in the Z-axis direction. Therefore, by using a plurality of sets of phase data corresponding to the distance to the power receiving device 50B in the Z-axis direction, it is possible to provide a power feeding device 100 that can transmit power so that the power receiver can efficiently receive power even at a short distance, according to the distance to the power receiving device 50B in the Z-axis direction. FD If there are no sets of phase data corresponding to the estimated opposing distance r FD The closest facing distance r FD The phase data corresponding to the above can be used.

[0118] Furthermore, the positional deviation detection unit 153 detects the positional deviation between the camera 140 and the marker 50A in the Y-axis direction, and if a positional deviation occurs, the distance estimation unit 154 reads out data indicating the degree of change in the pixel index number with respect to the positional deviation in the Y-axis direction from the memory 156, and calculates the facing distance r using the pixel index number corrected according to the degree of positional deviation in the Y-axis direction. FD Therefore, when there is a positional deviation between the camera 140 and the marker 50A in the Y-axis direction, the control unit 155 estimates the facing distance r FD By using multiple sets of phase data according to the above, it is possible to provide a power supply device 100 that can transmit power so that the power receiver can efficiently receive power even at short distances according to the distance to the power receiving device 50B in the Z-axis direction, even if there is a positional misalignment between the camera 140 and the marker 50A in the Y-axis direction.

[0119] Furthermore, the power ramping unit 130A performs power ramping of the envelope signal in accordance with the control timing of the camera 140, so that, for example, when the power supply device 100 is moving at a high speed, such as when the power supply device 100 is mounted on a vehicle and moving, it is possible to adjust the phase of the power transmission signal and perform power ramping in accordance with the timing of image acquisition.

[0120] Furthermore, power ramping unit 130A includes power ramping timing signal generation unit 131 that generates a power ramping timing signal that indicates the timing of power ramping of the envelope signal and whether or not to perform power ramping of the envelope signal, and phase adjustment timing signal generation unit 132 that generates a phase adjustment timing signal that causes phase shifter 120 to adjust the phase of the power transmission signal based on the power ramping timing signal generated by power ramping timing signal generation unit 131. Phase shifter 120 adjusts the phase of the power transmission signal in accordance with the phase adjustment timing signal. This makes it possible to match the timing of the adjustment of the phase of the power transmission signal based on the phase adjustment timing signal generated by phase adjustment timing signal generation unit 132 with the state where the intensity of the power transmission signal is reduced (power zero point) during power ramping based on the power ramping timing signal generated by power ramping timing signal generation unit 131, thereby suppressing the occurrence of discontinuities and spurious signals such as harmonics, thereby achieving stable power transmission.

[0121] Furthermore, power ramping unit 130A further includes control timing signal generation unit 133 that generates a control timing signal that indicates the control timing of camera 140, and power ramping timing signal generation unit 131 generates a power ramping timing signal in response to the control timing signal generated by control timing signal generation unit 133. Therefore, for example, when power feeding device 100 is moving fast, such as when power feeding device 100 is mounted on a vehicle and moving, it is possible to synchronize the timing of image acquisition based on the control timing signal generated by control timing signal generation unit 133 with the timing of adjustment of the phase of the power transmission signal based on the phase adjustment timing signal generated by phase adjustment timing signal generation unit 132 and the timing of a state (power zero point) where the intensity of the power ramping power transmission signal based on the power ramping timing signal generated by power ramping timing signal generation unit 131 is reduced, thereby suppressing the occurrence of discontinuities and spurious signals such as harmonics, thereby achieving stable power transmission.

[0122] Furthermore, power ramping unit 130A has coefficient memory 134 that stores coefficient data representing power ramping coefficients, and an output unit that outputs the coefficient data stored in coefficient memory 134 in response to a power ramping timing signal. Therefore, it is possible to stably output an envelope signal based on the power ramping coefficient represented by the coefficient data stored in coefficient memory 134, suppress the occurrence of discontinuities, and suppress the occurrence of spurious signals such as harmonics, thereby achieving stable power transmission.

[0123] The output section is selector 135, and the coefficient data is data indicating a power ramping coefficient of less than 1. Selector 135 outputs fixed data in which the power ramping coefficient is 1, or the coefficient data in response to the power ramping timing signal. Therefore, there is no need to store power ramping coefficients for when power ramping is not performed in coefficient memory 134, and the capacity of the coefficient data can be reduced, enabling the entire power supply device 100 to be made smaller.

[0124] The coefficient data is power ramping data that represents the transmission power of a transmission signal over time, the transmission power of which is adjusted by power ramping, and therefore, a stable envelope signal can be output, the occurrence of discontinuities can be suppressed, and the occurrence of spurious signals such as harmonics can be suppressed, thereby realizing stable power transmission.

[0125] Furthermore, since the power ramping data is a raised cosine time response, an envelope signal can be output stably and reliably, the occurrence of discontinuities is suppressed, and the occurrence of spurious signals such as harmonics is suppressed, thereby realizing stable power transmission.

[0126] The power ramping unit 130A performs power ramping so that the transmission power of the transmission signal changes continuously. Therefore, by using a transmission signal whose transmission power changes continuously, the occurrence of discontinuous points is suppressed, and the occurrence of spurious signals such as harmonics is suppressed, thereby realizing stable power transmission.

[0127] Furthermore, the elevation angle acquisition unit 152 calculates the coordinates of the mapping position obtained by mapping the position P2 onto the X axis using the focal length f of the fisheye lens. LThe elevation angle θa is calculated by dividing the angle θa by 1 / θ, so that the elevation angle θa can be easily calculated with a small amount of calculation, and the entire power supply device 100 can be made smaller in size.

[0128] Furthermore, since the coordinates of the mapping position are expressed by the value obtained by multiplying the radius vector r in polar coordinates by the cosine of the argument φ, the coordinates of the mapping position can be easily determined with a small amount of calculation, thereby enabling the entire power supply device 100 to be reduced in size.

[0129] Furthermore, the antenna elements 111 are grouped into subarrays 110A extending along the Y-axis direction, and the phase shifters 120 are connected to the subarrays 110A, respectively, and adjust the phase of the power transmission signal for each subarray 110A, thereby reducing the number of phase shifters 120. This allows the power feeding device 100 to be realized at low cost.

[0130] In the above, an embodiment has been described in which an image is acquired by camera 140, position P1 of marker 50A relative to camera 140 is converted to position P2, elevation angle θa is acquired based on position P2, and phase shifter 120 is controlled so that the direction of the beam radiated by array antenna 110 becomes elevation angle θa in the XZ plane. However, power supply device 100 is not limited to this embodiment. The power supply device 100 includes an array antenna 110 having a plurality of antenna elements 111 arranged two-dimensionally along the X-axis and Y-axis, a phase shifter 120 that adjusts the phase of a transmission signal supplied to the plurality of antenna elements 111 in the X-axis direction, a carrier wave output unit 130B that outputs a carrier wave for the transmission signal, a power ramping unit 130A that outputs an envelope signal representing the amplitude of the transmission signal and performs power ramping of the envelope signal, and a modulator 130C that multiplies the carrier wave and the envelope signal to output the transmission signal, and the power ramping unit 130A may be configured to cause the phase shifter 120 to adjust the phase of the transmission signal depending on the timing of power ramping of the envelope signal.

[0131] Therefore, even in a configuration in which the phase shifter 120 is not controlled so that the direction of the beam emitted by the array antenna 110 is at an elevation angle θa in the XZ plane, when the phase of the transmission signal is adjusted, the occurrence of discontinuities is suppressed, and the occurrence of spurious signals such as harmonics is suppressed, thereby achieving stable power transmission.

[0132] <Modification> 14 is a diagram showing a portion related to power ramping of a power supply device 100M according to a modified example of the embodiment. The power supply device 100M has a configuration in which the control timing signal of the power supply device 100 according to the embodiment is omitted. Since the other configurations are the same as those of the power supply device 100, the same components are denoted by the same reference numerals and redundant explanations will be omitted. The following description of the power supply device 100M will focus on the differences from the power supply device 100.

[0133] FIG. 14 is a diagram corresponding to FIG. 9 of the power supply device 100, and shows antenna elements 111 #1 to #N, phase shifter (PD) 120, power transmission signal generation unit 130, camera 140, elevation angle acquisition unit 152, and phase control units 155A #1 to #N and memory unit 156A.

[0134] <Power Transmission Signal Generator 130> The power transmission signal generation unit 130 includes a power ramping unit 130A, a carrier wave output unit 130B, a modulator 130C, and a BPF (Band Pass Filter) 130D. The power ramping unit 130A of the power supply device 100M is similar to the power ramping unit 130A of the power supply device 100 (see FIG. 9), except that the power ramping unit 130A does not output a control timing signal (see FIG. 9) that indicates the control timing of the camera 140.

[0135] <Power ramping section 130A> 15 is a diagram showing an example of the configuration of a power ramping section 130A of a power supply device 100M according to a modified example of the embodiment. The power ramping section 130A includes a power ramping timing signal generator 131, a phase adjustment timing signal generator 132, a coefficient memory 134, and a selector 135. The power ramping section 130A of the power supply device 100M is configured by removing the control timing signal generator 133 from the power ramping section 130A of the power supply device 100 (see FIG. 10), and by having the power ramping timing signal generator 131 generate a power ramping timing signal that indicates the timing for power ramping of the envelope signal and whether or not to perform power ramping.

[0136] <Two timing signals> FIG. 16 is a diagram showing an example of waveforms of the power ramping timing signal and the phase adjustment timing signal.

[0137] The power ramping timing signal is a pulsed signal that alternately repeats an H-level period ΔTu, an H-level period ΔTd+ΔTu, and an H-level period ΔTd. The period ΔTu is a ramp-up period that increases the power ramping coefficient, and the period ΔTd is a ramp-down period that decreases the power ramping coefficient. ΔTu and ΔTd are equal.

[0138] The phase adjustment timing signal is a signal obtained by delaying the power ramping timing signal by time t2. The phase shifter 120 adjusts the phase at the timing when the phase adjustment timing signal rises to an H level. Time t2 is a circuit delay adjustment width that adjusts the circuit delay from when the power ramping timing signal generation unit 131 outputs the power ramping timing signal until the power transmission signal reaches the phase shifter 120, and is particularly the time for adjusting the delay occurring in the BPF 130D. When performing power ramping, adjustment is made at time t2 to match the timing at which the power transmission signal and the phase adjustment timing signal reach the phase shifter 120.

[0139] 16 is performed, and the amplitude of the power transmission signal supplied to phase shifter 120 becomes zero when time t2 has elapsed since the start of period ΔTu of the power ramping timing signal shown in Fig. 16. This is the same as the timing at which the phase adjustment timing signal rises to H level. The timing at which the phase adjustment timing signal rises to H level is the timing at which phase shifter 120 adjusts the phase. By delaying the phase adjustment timing signal by time t2 relative to the power ramping timing signal in this way, phase shifter 120 adjusts the phase at the timing at which the amplitude of the power transmission signal becomes zero due to power ramping.

[0140] <Operation of power supply device 100M> FIG. 17 is a diagram illustrating an example of the operation of the power supply device 100M. FIG. 17 shows the power transmission signal output from the modulator 130C and the power transmission signal input to the phase shifter 120. The amplitude of the power transmission signal input to the phase shifter 120 is delayed by time t2 relative to the timing at which the amplitude of the power transmission signal output from the modulator 130C becomes zero due to power ramping, and is therefore zero. As shown in FIG. 16, a phase adjustment timing signal delayed by time t2 relative to the power ramping timing signal is input to the phase shifter 120, and therefore the timing is synchronized with the power transmission signal (input to the phase shifter 120) shown in FIG. 17. Therefore, the phase shifter 120 can adjust the phase at the timing at which the intensity of the power transmission signal supplied to the phase shifter 120 becomes zero due to power ramping, and the occurrence of discontinuities when the phase shifter 120 shifts the phase of the power transmission signal can be suppressed. As a result, the spread of spurious signals in the power transmission signal can be suppressed, and interference with other devices that may be present around the power receiving device 50B can be reduced.

[0141] Therefore, it is possible to provide a power feeding device 100M and a power feeding method that enable stable power transmission when adjusting the phases of power transmission signals transmitted from multiple antenna elements 111 to align the receiving potential phases. Also, since the modulator 130C multiplies the carrier wave output from the carrier wave output unit 130B by the envelope signal output from the power ramping unit 130A to output the transmission signal, it is possible to provide a power feeding device 100 that achieves both a compact circuit scale and power ramping of the transmission signal. Also, it is possible to suppress interference with other devices that may be present around the power receiving device 50B.

[0142] Furthermore, in power supply device 100M according to the modification of the embodiment, the timing at which camera 140 acquires an image and the timing at which power ramping is performed do not coincide, thereby reducing the amount of calculation required by power ramping section 130A and achieving further miniaturization. Note that, because the timing at which camera 140 acquires an image and the timing at which power ramping is performed do not coincide, power supply device 100M according to the modification of the embodiment is more suitable for applications involving slower movement than power supply device 100 according to the embodiment.

[0143] The above describes the power supply device and power supply method according to exemplary embodiments of the present invention. However, the present invention is not limited to the specifically disclosed embodiments, and various modifications and changes are possible without departing from the scope of the claims. [Explanation of symbols]

[0144] 50A marker 50B Power receiving device 100 Power supply device 110 Array Antenna 110A Sub-array 111 Antenna element 120 Phase shifter (an example of a phase adjustment unit) 130 Power transmission signal generation unit 130A Power Ramping Unit 130B Carrier wave output section 130C Modulator 130D BPF 131 power ramping timing signal generator (an example of a first timing signal generator) 132 phase adjustment timing signal generation unit (an example of a second timing signal generation unit) 133 control timing signal generation unit (an example of a third timing signal generation unit) 134 Coefficient memory (an example of a storage unit) 135 Selector (an example of an output section) 140 Camera (an example of an image acquisition unit) 141 Fisheye Lens 150 control device 151 Position derivation part 152 Elevation angle acquisition part 153 Position deviation detection unit 154 Distance estimation unit 155 Control Unit 156 memory

Claims

1. an array antenna having a plurality of antenna elements arranged two-dimensionally along a first axis and a second axis; a phase adjusting unit that adjusts the phases of the power transmission signals supplied to the plurality of antenna elements in the first axis direction; an image acquisition unit that acquires an image through a fisheye lens; a position derivation unit that converts a first position of a marker included in an image acquired by the image acquisition unit with respect to the image acquisition unit into a second position in polar coordinates on a first plane that includes the first axis and the second axis; an elevation angle acquisition unit that acquires, based on the second position, an elevation angle of a projection position obtained by projecting the first position onto a second plane including the first axis and a third axis, with respect to the third axis within the second plane; a control unit that controls the phase adjustment unit so that the direction of the beam radiated by the array antenna becomes the elevation angle within the second plane; a carrier wave output unit that outputs a carrier wave; a power ramping unit that outputs an envelope signal representing the amplitude of the power transmission signal and performs power ramping on the envelope signal; a modulator that multiplies the carrier wave and the envelope signal to output the transmission signal; Including, The power ramping unit causes the phase adjusting unit to adjust the phase of the power transmission signal in accordance with a timing of power ramping of the envelope signal.

2. The power supply device according to claim 1 , wherein the power ramping unit performs power ramping of the envelope signal in accordance with a control timing of the image acquisition unit.

3. The power ramping unit a first timing signal generating unit that generates a power ramping timing signal that indicates timing for power ramping the envelope signal and whether or not power ramping of the envelope signal is to be performed; a second timing signal generator that generates a phase adjustment timing signal that causes the phase adjuster to adjust the phase of the power transmission signal based on the power ramping timing signal generated by the first timing signal generator; and The power supply device according to claim 1 , wherein the phase adjuster adjusts the phase of the power transmission signal in response to the phase adjustment timing signal.

4. the power ramping unit further includes a third timing signal generating unit that generates a control timing signal that indicates a control timing of the image acquisition unit; The power supply device according to claim 3 , wherein the first timing signal generating unit generates the power ramping timing signal in response to the control timing signal generated by the third timing signal generating unit.

5. The power ramping unit a storage unit for storing coefficient data representing a power ramping coefficient; an output unit that outputs the coefficient data stored in the storage unit in response to the power ramping timing signal; The power supply device according to claim 3 or 4, comprising:

6. the output unit is a selector, the coefficient data is data representing a value of the power ramping coefficient that is less than 1, The power supply device according to claim 5 , wherein the selector outputs fixed data in which the power ramping coefficient is 1 or the coefficient data in response to the power ramping timing signal.

7. The power supply device according to claim 6 , wherein the coefficient data is power ramping data that represents, in a time series manner, the transmission power of the transmission signal whose transmission power is adjusted by the power ramping.

8. The power supply device according to claim 7 , wherein the power ramping data is a raised cosine time response.

9. The power supply device according to claim 1 , wherein the power ramping section performs the power ramping so that the transmission power of the power transmission signal changes continuously.

10. The power supply device according to claim 1 , wherein the elevation angle acquisition unit obtains, as the elevation angle, a value obtained by dividing coordinates of a mapping position obtained by mapping the second position onto the first axis by a focal length of the fisheye lens.

11. The power supply device according to claim 10 , wherein the coordinates of the mapping position are expressed by a value obtained by multiplying a radius vector in the polar coordinate system by a cosine of an angle of deviation.

12. the plurality of antenna elements are grouped into a plurality of subarrays extending along the second axis; The power feeding device according to claim 1 , wherein the phase adjustment unit is a plurality of phase shifters connected to the plurality of subarrays, respectively, and configured to adjust the phase of the power transmission signal for each subarray.

13. an array antenna having a plurality of antenna elements arranged two-dimensionally along a first axis and a second axis; a phase adjusting unit that adjusts the phases of the power transmission signals supplied to the plurality of antenna elements in the first axis direction; a carrier wave output unit that outputs a carrier wave; a power ramping unit that outputs an envelope signal representing the amplitude of the power transmission signal and performs power ramping on the envelope signal; a modulator that multiplies the carrier wave and the envelope signal to output the transmission signal; Including, The power ramping unit causes the phase adjusting unit to adjust the phase of the power transmission signal in accordance with a timing of power ramping of the envelope signal.

14. an array antenna having a plurality of antenna elements arranged two-dimensionally along a first axis and a second axis; a phase adjusting unit that adjusts the phases of the power transmission signals supplied to the plurality of antenna elements in the first axis direction; an image acquisition unit that acquires an image through a fisheye lens; a position derivation unit that converts a first position of a marker included in an image acquired by the image acquisition unit with respect to the image acquisition unit into a second position in polar coordinates on a first plane that includes the first axis and the second axis; an elevation angle acquisition unit that acquires, based on the second position, an elevation angle of a projection position obtained by projecting the first position onto a second plane including the first axis and a third axis, with respect to the third axis within the second plane; a carrier wave output unit that outputs a carrier wave; a power ramping unit that outputs an envelope signal representing the amplitude of the power transmission signal and performs power ramping on the envelope signal; a modulator that multiplies the carrier wave and the envelope signal to output the transmission signal; In a power supply device including: controlling the phase adjustment unit so that the direction of the beam radiated by the array antenna is at the elevation angle within the second plane; a phase adjusting unit that adjusts a phase of the power transmission signal in accordance with a timing of power ramping of the envelope signal;

Images