JP7350961B1 - Power receiving device, receiving device, terminal device, wireless power transmission system and communication system - Google Patents

Abstract

The present invention provides an antenna device that can achieve both high antenna gain and a wide directivity angle range.
An antenna device includes a plurality of antenna units each having a plurality of antenna elements arranged at intervals of 0.5 times or more the wavelength of a radio wave to be received, and an angular direction of a directional beam of the plurality of antenna units. a connection circuit having a plurality of connection paths connected to each of the plurality of antenna units with mutually different path lengths such that the antenna units have different path lengths. The plurality of antenna elements are arranged at intervals of one or more times the wavelength of the radio waves to be received so that the antenna unit has a plurality of directional beams, and the path lengths of the plurality of connection paths are The angular directions of the directional beams may be set to be different from each other.
[Selection diagram] Figure 16

Description

The present invention relates to an antenna device that can be used for receiving radio waves in wireless power transmission, communication, etc., as well as a power receiving device, a receiving device, a terminal device, a wireless power transmission system, and a communication system including the antenna device.

2. Description of the Related Art Conventionally, as an antenna device of this type, an antenna device including an array antenna composed of a plurality of antenna elements is known. For example, Patent Document 1 discloses an array antenna for wireless power transmission and reception in which a plurality of antenna elements such as patch antennas are lined up.

JP2016-213927A

In an antenna device capable of receiving radio waves in the above-mentioned wireless power transmission or communication, there is a problem of wanting to achieve both high antenna gain and a wide directivity angle range.

An antenna device according to one aspect of the present invention includes a plurality of antenna units each having a plurality of antenna elements arranged at intervals of 0.5 times or more the wavelength of radio waves to be received, and a directional beam of the plurality of antenna units. and a connection circuit having a plurality of connection paths connected to each of the plurality of antenna units with mutually different path lengths so that the angular directions of the antenna units are different from each other.

In the antenna device, the plurality of antenna elements are arranged at intervals of one or more times the wavelength of the radio waves to be received so that the antenna unit has a plurality of directional beams, and the path lengths of the plurality of connection paths are: The angular directions of the plurality of directional beams may be set to be different from each other among the plurality of antenna units.

In the antenna device, the plurality of antenna units may be arranged such that an antenna element of an antenna unit other than the antenna unit is located between the plurality of antenna elements of the antenna unit.

In the antenna device, the plurality of antenna elements in the plurality of antenna units may be arranged one-dimensionally or two-dimensionally.

In the antenna device, the radio waves to be received may be millimeter waves.

According to another aspect of the present invention, a power receiving device used for wireless power transmission includes one of the antenna devices and a plurality of antenna units connected to each of the plurality of antenna units via a connection circuit including the plurality of connection paths. and a DC combining circuit that combines and outputs a plurality of DC powers output from the plurality of rectifier circuits.

A wireless power transmission system according to still another aspect of the present invention includes the power receiving device and a power transmitting device that transmits radio waves for wireless power transmission toward the power receiving device.

A receiving device used for communication according to still another aspect of the present invention includes any one of the antenna devices and a plurality of antenna units connected to each of the plurality of antenna units via a connection circuit including the plurality of connection paths. It includes a phase adjustment circuit and a combining circuit that combines the plurality of received signals outputted from the plurality of phase adjustment circuits in the same phase and outputs the same.

A receiving device used for communication according to still another aspect of the present invention includes any one of the antenna devices and a plurality of antenna units connected to each of the plurality of antenna units via a connection circuit including the plurality of connection paths. The device includes an A/D converter and a combining circuit that performs in-phase combining of a plurality of received signals outputted from the plurality of A/D converters using digital processing and outputs the resultant signal.

A receiving device used for communication according to still another aspect of the present invention includes any one of the antenna devices and a plurality of antenna units connected to each of the plurality of antenna units via a connection circuit including the plurality of connection paths. The device includes a receiver and a signal processing unit that performs MIMO signal processing on a plurality of received signals output from the plurality of receivers.

A receiving device used for communication according to still another aspect of the present invention includes a receiving device having any of the antenna devices described above, and a transmitting device that performs wireless communication with the receiving device.

A terminal device according to still another aspect of the present invention includes a power receiving device or a receiving device having any of the antenna devices described above.

The terminal device may be an IoT connectable to the Internet.

According to the present invention, it is possible to achieve both high antenna gain and a wide directivity angle range.

FIG. 1 is an explanatory diagram showing an example of a wireless power transmission system to which the antenna device according to the embodiment can be applied. FIG. 7 is an explanatory diagram showing an example of a directivity pattern of a single antenna element according to a reference example. FIG. 1 is a perspective view of an array antenna having a plurality of antenna elements according to an embodiment. (a) to (d) are explanatory diagrams showing examples of directivity patterns when the element spacing is 0.5λ, 2λ, 4λ, and 8λ in the array antenna of FIG. 3, respectively. FIG. 2 is an explanatory diagram showing an example of a one-dimensional array antenna including a plurality of antenna units of the antenna device according to the embodiment. (a) to (d) are explanatory diagrams of the element arrangement of each of a plurality of antenna units. (a) to (d) are explanatory diagrams showing examples of directivity patterns of a plurality of antenna units in FIG. 5, respectively. FIG. 7 is an explanatory diagram showing the directivity patterns of FIGS. 7(a) to 7(d) superimposed. FIG. 9 is an explanatory diagram of the effect of the directivity pattern of FIG. 8; FIG. 2 is an explanatory diagram showing an example of a two-dimensional array antenna that constitutes a plurality of antenna units of the antenna device according to the embodiment. FIG. 11 is an explanatory diagram of a part of the two-dimensional array antenna of FIG. 10. FIG. 11 is an explanatory diagram of an arrangement of a plurality of antenna elements forming a first antenna unit in the two-dimensional array antenna of FIG. 10; (a) to (p) are explanatory diagrams showing examples of three-dimensional directivity patterns of the first to sixteenth antenna units in the two-dimensional array antenna of FIG. 10, respectively. An explanatory diagram in which the three-dimensional directivity patterns of FIGS. 13(a) to 13( p ) are superimposed and displayed. FIG. 4 is an explanatory diagram showing an example of a connection circuit for the antenna unit including the array antenna of FIG. 3; FIG. 6 is an explanatory diagram showing an example of the configuration of a power receiving device for wireless power transmission having the array antenna of FIG. 5; 11 is an explanatory diagram showing an example of the configuration of a power receiving device for wireless power transmission having the array antenna of FIG. 10. FIG. FIG. 1 is an explanatory diagram showing an example of the configuration of a communication receiving device having an antenna device according to an embodiment. FIG. 7 is an explanatory diagram showing another example of the configuration of a communication receiving device having an antenna device according to an embodiment. FIG. 7 is an explanatory diagram showing still another example of the configuration of a communication receiving device having an antenna device according to an embodiment. FIG. 3 is an explanatory diagram showing another example of a system to which the antenna device according to the embodiment can be applied. 22 is a block diagram illustrating an example of the configuration of a base station and a terminal device that constitute the system of FIG. 21. FIG . FIG. 7 is an explanatory diagram showing still another example of a system to which the antenna device according to the embodiment can be applied.

Embodiments of the present invention will be described below with reference to the drawings.
The antenna device according to the embodiment described in this document includes an antenna unit in which a plurality of antenna elements are arranged at predetermined intervals (for example, intervals of 0.5 times or more or 1 times or more the wavelength of the radio wave to be received). High antenna gain and a wide directional angle range can be achieved by providing multiple antenna units and setting the path lengths of multiple connection paths connected to the multiple antenna units so that the angular directions of the directional beams of the multiple antenna units are different from each other. This is an antenna device with a simple configuration that can achieve both (wide-angle directivity). In particular, the antenna device according to the embodiment is suitable as an antenna device for a power receiving device (also referred to as a “power receiving rectenna device”) of a wireless power transmission (WPT) system that uses millimeter wave radio waves.

FIG. 1 is an explanatory diagram showing an example of a wireless power transmission system to which the antenna device according to the present embodiment can be applied. The wireless power transmission system 10 of the present embodiment includes a power transmitting device 20 that transmits radio waves of power transmission signals, and a power receiving device (DC power) 30 that receives the radio waves transmitted from the power transmitting device 20 and outputs DC power. Be prepared. Radio waves for wireless power transmission are, for example, microwaves or millimeter waves.

The power transmission device 20 includes an antenna device 21 that is an array antenna in which a plurality of antenna elements are two-dimensionally arranged. The array antenna of the power transmission device 20 may be one in which a plurality of antennas are arranged one-dimensionally or three-dimensionally.

The power receiving device 30 includes an antenna device 31 including an array antenna in which a plurality of antenna elements 311 are two-dimensionally arranged. The antenna element 311 is, for example, a patch antenna. The array antenna of the power receiving device 30 may be one in which a plurality of antennas are arranged one-dimensionally or three-dimensionally. The power receiving device 30 also includes a rectifier circuit group 32 including a plurality of rectifier circuits (rectifiers) provided to correspond to the plurality of antenna elements 311 of the antenna device 31, and outputs of the plurality of rectifier circuits of the rectifier circuit group 32. and a DC synthesis circuit 33 that synthesizes the signals and outputs DC power.

In the wireless power transmission system 10 configured as described above, the power transmitting device 20 also serves as a base station of a mobile communication system, for example, and the terminal device equipped with the power receiving device 30 that receives power is various sensor devices that can be connected to a communication network such as the Internet. It may be an IoT device such as. Millimeter waves (radio waves in the 30 GHz to 300 GHz band), which can easily form thin beams (also called "pencil beams") to avoid interference, are used as radio waves for wireless power transfer (WPT) for such IoT devices. is being considered. In wireless power transmission (WPT) using millimeter waves, it is necessary to increase the input power to the rectifier circuit in order to extend the power transmission distance and obtain high RF-DC conversion efficiency in the rectifier circuit. Therefore, an antenna device with high gain is required as an antenna device for the power receiving device. In order to increase the gain of the antenna device, it is possible to make the beam narrower by narrowing the beam width of the directional main beam formed by the antenna device and to make the aperture larger. However, when using a narrow beam, it is necessary to perform beam control to direct the beam of the antenna device on the power receiving device side toward the power transmitting device, but it is unrealistic to perform beam control that requires power on the terminal device side. If an omnidirectional antenna is used, it is possible to receive radio waves from a power transmission device without performing beam control, but it is difficult to achieve high gain with an omnidirectional antenna. Furthermore, if an antenna with a large aperture is used, the size of a terminal device such as an IoT device will increase.

Therefore, in this embodiment, as shown below, a plurality of antenna units each having a plurality of antenna elements arranged at predetermined intervals (for example, an interval of 0.5 times or more or 1 times or more the wavelength of the radio wave to be received) are provided. By setting the path lengths of the multiple connection paths connected to the multiple antenna units so that the angular directions of the directional beams of the multiple antenna units are different from each other, high antenna gain and wide directivity can be achieved with a simple configuration. We aim to balance both sexual and angle ranges.

FIG. 2 is an explanatory diagram showing an example of a directivity pattern 310D of a single antenna element according to a reference example. In the case of a single antenna element such as a patch antenna, as illustrated in FIG. The vertical beam width (φ), which is the full width at the half-value (−3 dB) of the peak power, is wide at 65° in both cases, but the peak gain G (8.6 dBi) of the directional pattern 310D is low.

FIG. 3 is a perspective view of an array antenna 310 having a plurality of antenna elements 311(1) to 311(4) according to the embodiment. The example in FIG. 3 is an example of a four-element linear array antenna in which four antenna elements 311(1) to 311(4) are one-dimensionally arranged at a predetermined interval d.

FIGS. 4A to 4D are explanatory diagrams showing examples of directivity patterns when the element spacing is 0.5λ, 2λ, 4λ, and 8λ in the array antenna 310 of FIG. 3, respectively. Here, "λ" is the wavelength of the radio wave to be received. When the element spacing in FIG. 4(a) is 0.5λ, the number of directional beams (hereinafter also referred to as "beams") of the directional pattern 310D is one, and the beam width is greater than that of a single element. is also narrower, but the gain G is 12.9 dBi, which is higher than in the single element case. As the element spacing increases to 2λ, 4λ, and 8λ, the beams of the directional pattern 310D are divided into 3, 7, and 15 beams, as shown in FIGS. 4(b) to 4(d). is formed, and the peak gain G is as high as 14.6 dBi to 14.7 dBi.

In one configuration example of the antenna device 31 of this embodiment, for example, it is configured to include a plurality of antenna units each including an array antenna 310 having four antenna elements 311(1) to 311(4) shown in FIG. . Then, a connection circuit having a plurality of connection paths connecting to the plurality of antenna units is configured to be connected to each of the plurality of antenna units with mutually different path lengths so that the angular directions of the directional beams are different from each other. do.

For example, when four antenna units each consisting of a four-element array antenna with an element spacing of 0.5λ as shown in FIG. A connection circuit having a plurality of connection paths connecting to a plurality of antenna units so as to be staggered by each other is connected to each of the plurality of antenna units with different path lengths so that the angular directions of the directional beams are different from each other. Configure the connection circuit.

Further, for example, when four antenna units are provided, each consisting of a four-element array antenna of 2λ, 4λ, or 8λ, in which the element spacing shown in FIG. 4(b), (c), or (d) is one or more times the wavelength λ, The connection circuit is configured to be connected to each of the plurality of antenna units through connection paths having different path lengths so that the angular directions of the plurality of beams are different among the four antenna units. In this case, the connection circuit may be configured so that the null portion of the beam of the antenna unit is filled with the beam of another antenna unit other than the antenna unit.

FIG. 5 is an explanatory diagram showing an example of a one-dimensional array antenna 310 including a plurality of antenna units of the antenna device according to the embodiment. FIGS. 6(a) to 6(d) are explanatory diagrams of a plurality of antenna units 310(1) to 310(4) forming the one-dimensional array antenna of FIG. 5, respectively. In FIG. 5, a one-dimensional array antenna 310 is a linear array antenna in which 16 antennas (for example, patch antennas) are arranged in the y direction in the figure, and the element spacing d0 between adjacent antennas is 0.5λ, and 4 It consists of two antenna units. The first antenna unit 310(1) in FIG. 6(a) has four antenna elements 311(1) with an element spacing of d1. The second antenna unit 310(2) in FIG. 6(b) has four antenna elements 311(2) with an element spacing of d2. The third antenna unit 310(3) in FIG. 6(c) has four antenna elements 311(3) with an element spacing of d3. The fourth antenna unit 310(4) in FIG. 6(d) has four antenna elements 311(4) with an element spacing of d4. The element spacings d1, d2, d3, and d4 in each antenna unit 310(1) to 310(4) are each 2λ.

Further, in the one-dimensional array antenna 310 of FIG. 5, a plurality of antenna units are arranged such that an antenna element of an antenna unit other than the antenna unit is located between the plurality of antennas of the antenna unit. For example, between two antenna elements 311(1) of the first antenna unit, there are one antenna element 311(2), 311(3), and 311(4) of the other second, third, and fourth antenna units. Four antenna units are arranged so that each antenna unit is located at a different location.

7(a) to 7(d) are explanatory diagrams showing examples of directivity patterns 310D(1) to 310D(4) of the plurality of antenna units 310(1) to 310(4) in FIG. 5, respectively. be. Directivity patterns 310D(1) to 310D(4) of each antenna unit each have four beams 310B(1) to 310B(4), and the angle between the beams is about 30°. Then, a connection circuit having a plurality of connection paths (connection lines) connected to the antenna units 310(1) to 310(4) is configured so that the null portion of the beam of the antenna unit is filled with the beam of other antenna units. are doing. For example, the angular range of the null portion of the directivity pattern 310D(1) of the first antenna unit 310(1) shown in FIG. , the connection path (connection line) to each antenna unit in the connection circuit is filled with beams of directional patterns 310D(2) to 310D(4) of the third and fourth antenna units 310(2) to 310(4). ) are set with different route lengths. Thereby, the phase of the power reception signal received by each antenna unit is adjusted. With this phase adjustment, the antenna units 310(2) to 310() in FIGS. 7(b) to 7(d) are based on the directivity pattern 310D(1) of the antenna unit 310(1) in FIG. 7(a). The directivity patterns 310D(2) to 310D(4) in 4) are directivity patterns tilted by θ=+7.5°, +15°, and −7.5° in the xy plane, respectively.

FIG. 8 is an explanatory diagram in which the directivity patterns of FIGS. 7(a) to 7(d) are displayed in a superimposed manner. The directivity pattern 310D of the entire array antenna 310 of the antenna device 31 shown in FIG. 8 is a pattern obtained by superimposing the directivity patterns 310D(1) to 310D(4) of FIGS. 7(a) to 7(d). . Therefore, even if the radio waves 900 from the power transmission device arrive with a certain degree of spread as shown in FIG. 9, the radio waves can be efficiently received. Further, even if the radio waves 901 from the power transmission device arrive via multiple paths, the plurality of radio waves 901 arriving via the plurality of paths can be efficiently received.

FIG. 10 is an explanatory diagram showing an example of a two-dimensional array antenna 310' that constitutes a plurality of antenna units of the antenna device according to the embodiment. FIG. 11 is an explanatory diagram of a part of the two-dimensional array antenna 310' of FIG. 10. FIG. 12 is an explanatory diagram of an arrangement of a plurality of antenna elements 311(1) constituting the first antenna unit in the two-dimensional array antenna 310' of FIG. 10.

In FIG. 10, a two-dimensional array antenna 310' is an array antenna in which a total of 256 antennas (for example, patch antennas), 16 antennas in the y direction and 16 antennas in the z direction, are arranged. As shown, the element spacing dy0, dz0 of antennas adjacent to each other in the y direction and the z direction is 0.5λ, and 16 antenna units are configured. Further, the first, second, . . . , and 16th antenna units each include 16 antenna elements 311(1), 311(2), . 311 (16). For example, as shown in FIG. 12, the first antenna unit has 16 antenna elements 311(1) with an element spacing in the y direction of dy1 and an element spacing in the z direction of dz1.

Moreover, as shown in FIG. 10, a plurality of first, second, ..., sixteenth Antenna unit is installed. For example, between the plurality of antenna elements 311(1) of the first antenna unit, the antenna elements 311(2), 311(3), . Sixteen antenna units are arranged so that (16) is located.

FIGS. 13(a) to 13(p) are explanatory diagrams showing examples of directivity patterns 310D(1) to 310D(16) of the plurality of antenna units in FIG. 10, respectively. Each of the three-dimensional directivity patterns 310D(1) to 310D(16) formed by each antenna unit has a plurality of beams. The connection circuit is configured so that the null portion of the beam of the antenna unit is filled with the beam of another antenna unit. For example, the range of the null portion of the directivity pattern 310D(1) of the first antenna unit shown in FIG. 13(a) may be changed to the other second, third, . ...The power received by each antenna unit is varied by varying the path length to each antenna unit in the connection circuit so that the beams of the directional patterns 310D(2) to 310D(16) of the 16th antenna unit are filled. Adjusting the phase of the signal. With this phase adjustment, the antenna units 310(2) to 310() in FIGS. 13(b) to 13(p) are based on the directivity pattern 310D(1) of the antenna unit 310(1) in FIG. 13(a). The directivity patterns 310D(2) to 310D(16) of 16) are each a directivity pattern in which the angle θ in the xy plane and the angle φ in the xz plane are inclined by a predetermined angle.

FIG. 14 is an explanatory diagram in which the directivity patterns 310D(1) to 310D(16) of FIGS. 13(a) to 13(p) are displayed superimposed in a three-dimensional space. As shown in FIG. 14, the three-dimensional directivity pattern 310D of the entire two-dimensional array antenna 310' of the antenna device 31 is the directivity pattern 310D of FIGS. The pattern is a superposition of 1) to 310D (16). Therefore, even if the radio waves from the power transmission device arrive with a certain degree of spread in three-dimensional space, the radio waves can be efficiently received. Furthermore, even if the radio waves from the power transmission device arrive through multiple paths in three-dimensional space, the multiple radio waves arriving via the multiple paths can be efficiently received.

FIG. 15 is an explanatory diagram showing an example of the connection circuit 312 for the antenna unit consisting of the array antenna 310 of FIG. 3. In FIG. 15, the antenna device 31 includes an array antenna 310 having four antenna elements 311(1) to 311(4) constituting an antenna unit, and a connection circuit 312 that connects the array antenna 310 and a rectifier circuit 321. Equipped with. The connection circuit 312 connects connection lines 313(1) to 313(4), which are part of the connection paths connected to antenna elements 311(1) to 311(4), respectively, and connection lines 313(1) to 313(4). ) is connected to a single rectifier circuit 321 via a two-stage parallel circuit.

In the connection circuit 312, the path length L1 of the connection line between each of the four antenna elements 311(1) to 311(4) and the rectifier circuit 321 is the same length when the beam direction is 0°. However, when changing the beam direction, the path length of the connection circuit 312 connected to each antenna element 311(1) to 311(4) changes. A plurality of antenna units 310 having different path lengths of connection circuits 312 connected to each antenna element 311(1) to 311(4) are connected to form a broad beam as a whole.

FIG. 16 is an explanatory diagram showing an example of the configuration of a power receiving device 30 for wireless power transmission having the array antenna 310 of FIG. 5. As shown in FIG. In FIG. 16, the power receiving device 30 includes an antenna device 31 consisting of the one-dimensional array antenna of FIG. 5 configured of four antenna units, and a connection circuit consisting of a plurality of connection paths (connection lines) for each of the four antenna units. The rectifier circuit group 32 consists of four rectifier circuits 321(1) to 321(4) connected via 312 (see FIG. 15), and the output from the four rectifier circuits 321(1) to 321(4). and a direct current (DC) combining circuit 33 that combines and outputs the plurality of DC powers. As illustrated in FIGS. 7(a) to 7(d) and FIG. 8, the connection circuit 312 connects the antenna unit 310 (one ) to 310(4) are set. That is, the antenna units 310(1) to 310(4) whose connection paths (connection lines) have different path lengths are bundled and connected by connection lines having the same line length to form a broad beam as a whole.

FIG. 17 is an explanatory diagram showing an example of the configuration of a power receiving device 30 for wireless power transmission having the array antenna of FIG. 10. The power receiving device 30 in FIG. 17 includes an antenna device 31 consisting of a two-dimensional array antenna (see FIG. 10) made up of 16 antenna units, and a plurality of connection paths (connection lines) connected to each of the 16 antenna units. A rectifier circuit group 32 consisting of 16 rectifier circuits 321(1) to 321(16) connected via a connection circuit 312, and outputs from the 16 rectifier circuits 321(1) to 321(16). A direct current (DC) combining circuit 33 that combines and outputs a plurality of direct current powers is provided. As illustrated in FIGS. 13(a) to 13(p) and FIG. 14, the connection circuit 312 connects the antenna unit 310 (one ) to 310(16) are set. That is, the antenna units 310(1) to 310(16) whose connection paths (connection lines) have different path lengths are bundled and connected by connection lines having the same line length to form a broad beam as a whole.

FIG. 18 is an explanatory diagram showing an example of the configuration of a communication receiving device 45 having the antenna device 31 according to the embodiment. FIG. 18 shows a configuration example of a receiving device 45 that performs analog signal processing. Note that the antenna device 31 of the receiving device 45 in FIG. 18 has the same configuration as the antenna device 31 in the power receiving device 30 in FIG. 16 described above, and therefore a description thereof will be omitted.

In FIG. 18, the receiving device 45 includes an antenna device 31 consisting of a one-dimensional array antenna (see FIG. 5) made up of four antenna units, and a plurality of connection paths (connections) for each of the four plurality of antenna units. A phase adjustment circuit group 34 consisting of a plurality of phase adjustment circuits 341(1) to 341(4) connected via a connection circuit 312 consisting of a ), the combining circuit 35 combines the plurality of received signals outputted from ) in the same phase and outputs the same.

FIG. 19 is an explanatory diagram showing another example of the configuration of the communication receiving device 46 including the antenna device 31 according to the embodiment. FIG. 19 shows a configuration example of a receiving device 46 that performs digital signal processing. Note that the antenna device 31 of the receiving device 46 in FIG. 19 has the same configuration as the antenna device 31 in the power receiving device 30 in FIG. 16 described above, and therefore a description thereof will be omitted.

In FIG. 19, the receiving device 46 includes an antenna device 31 consisting of a one-dimensional array antenna (see FIG. 5) composed of four antenna units, and a plurality of connection paths for each of the four plurality of antenna units. An A/D converter group 37 consisting of a plurality of A/D converters 371(1) to 371(4) connected via a connection circuit 312, and four A/D converters 371(1) to 371 (4) A digital synthesis circuit 38 that digitally processes and outputs the in-phase synthesis of the plurality of received signals output from the apparatus.

FIG. 20 is an explanatory diagram showing still another example of the configuration of the communication receiving device 47 having the antenna device 31 according to the embodiment. FIG. 20 shows a configuration example of a receiving device 47 that performs MIMO signal processing. The antenna device 31 of the receiving device 47 in FIG. 20 has the same configuration as the antenna device 31 in the power receiving device 30 in FIG. 16 described above, and therefore a description thereof will be omitted.

In FIG. 20, the receiving device 47 includes an antenna device 31 consisting of a one-dimensional array antenna (see FIG. 5) composed of four antenna units, and a plurality of connection paths for each of the four plurality of antenna units. A receiver group 390 consisting of a plurality of receivers 391(1) to 391(4) connected via a connection circuit 312, and a plurality of receivers output from the four receivers 391(1) to 391(4). A MIMO signal processing unit 39 that performs MIMO signal processing on the received signal is provided.

Note that the receiving devices 45, 46, and 47 shown in FIGS. 18, 19, and 20 are configuration examples in which the antenna device 31 is a one-dimensional array antenna composed of four antenna units. Instead of the one-dimensional array antenna, the antenna device 31 may be configured to include a two-dimensional array antenna (see FIG. 10) made up of 16 antenna units, similar to the power receiving device of FIG. 17 described above. .

FIG. 21 is an explanatory diagram showing another example of a system to which the antenna device 31 according to the embodiment can be applied. The system of FIG. 21 includes a cellular base station 25 that forms a communication area (cell) 25A, and a power supply that enables wireless communication with the base station 25 by connecting to the base station 25 when located in the communication area 25A. It has a target terminal device (hereinafter also referred to as "UE" (user equipment)) 40. The base station 25 also functions as a transmitting device capable of wireless communication with the UE 40.

The UE 40 may be a mobile station of a mobile communication system, or may be a combination of a communication device (for example, a mobile communication module) and various devices. The UE 40 includes an antenna device having an array antenna similar to the antenna device 31 having the above configuration having a plurality of antenna elements. UE 40 may be an IoT device (also referred to as "IoT equipment").

In FIG. 21, the base station 25 is equipped with an antenna 251 having a plurality of array antennas each having a large number of antenna elements, and performs communication using a massive MIMO (hereinafter also referred to as "mMIMO") transmission method with a plurality of UEs 40. be able to. mMIMO is a wireless transmission technology that achieves high-capacity, high-speed communication by transmitting and receiving data using the antenna 251. Further, communication can be performed using a MU (Multi User)-MIMO transmission method that performs beamforming to form beams 25B in time division or simultaneously for each of the plurality of UEs 40. By performing MU-MIMO transmission using a multi-element array antenna, it is possible to direct and communicate an appropriate beam to each UE 20 according to the communication environment of each UE 40, thereby improving the communication quality of the entire cell. Moreover, since communication with a plurality of UEs 40 can be performed using the same radio resource (time/frequency resource), system capacity can be expanded.

Further, in FIG. 21, a part of the communication area 25A is a wireless power transmission area (hereinafter referred to as "WPT area") 25A' where wireless power transmission is performed from the base station 25 to the terminal device 40. The WPT area 25A' may be smaller than the communication area 25A as shown in the figure, or may have the same or approximately the same size and location as the communication area 25A.

In the WPT area 25A', unused radio resources (resource blocks) that are not used for communication among resource blocks that are a plurality of radio resources (time/frequency resources) constituting a downlink radio frame from the base station 25 are ) is used as a wireless power transmission block. In the downlink radio frame to the UE 40, the base station 25 sends a dummy signal for wireless power transmission (hereinafter also referred to as "WPT dummy signal") to a wireless power transmission block (WPT block) which is a wireless resource that is not used for communication. ) is generated and transmitted to the UE 40.

In particular, in 5th generation or later generation mobile communication systems, a technology called lean carrier has been proposed in which the minimum necessary reference signals (RS) and control signals are placed only on some subcarriers of a radio frame. Therefore, it is expected that wireless power transmission to the UE 40 will be performed by effectively utilizing the unused radio resources in the radio frame.

The radio wave of the communication signal transmitted and received between the base station 25 and the UE 40 and the radio wave of the transmission signal to which the WPT dummy signal is assigned, which is transmitted from the base station 25 to the UE 40, are, for example, millimeter waves or microwaves.

FIG. 22 is a block diagram showing an example of the main configurations of the base station 25 and the terminal equipment (UE) 40 that make up the system of FIG. 21. The base station 25 includes a base station device 250 and an antenna 251. The antenna 251 is, for example, an array antenna having a large number of antenna elements as shown in FIG. 21. The antenna 251 may be single or plural. For example, a plurality of antennas 251 may be arranged corresponding to a plurality of sector cells.

Base station device 250 includes a communication signal processing section 260 and a radio processing section 270. The communication signal processing unit 260 processes signals such as various user data and control information transmitted and received with the UE 40.

During downlink communication to the UE 40, the communication signal processing unit 260 generates a downlink transmission signal including a WPT dummy signal using an unused radio resource that is not used for communication among a plurality of radio resources. generate.

The radio processing unit 270 transmits the transmission signal generated by the communication signal processing unit 260 from the antenna 251 to the UE 40, and outputs the reception signal received from the UE 40 via the antenna 251 to the communication signal processing unit 260.

Furthermore, the wireless processing unit 270 controls one or more beams formed by the antenna 251 based on the BF control signal. Furthermore, the radio processing unit 270 transmits a downlink transmission signal including the WPT dummy signal generated by the communication signal processing unit 260 to the UE 40 via the antenna 251.

In FIG. 22, the UE 40 includes an antenna device 410, a wireless processing section 420, a communication signal processing section 430, a power output section 440, and a battery 450, which have the same configuration as the antenna device according to the present embodiment described above. Antenna device 410 has, for example, a small array antenna having a plurality of antenna elements. The wireless processing unit 420 transmits transmission signals such as feedback information and user data generated by the communication signal processing unit 430 from the antenna device 410 to the base station 25, and transmits received signals received from the base station 25 via the antenna device 410. is output to the communication signal processing section 430.

The wireless processing unit 420 receives the transmission signal including the WPT dummy signal transmitted from the base station 25. The power output unit 440 has, for example, a rectifier circuit, and outputs the power of the received signal that has received the transmission signal including the WPT dummy signal from the base station 25 as received power for battery charging. The battery 450 can be charged by the received power output from the power output unit 440.

FIG. 23 is an explanatory diagram showing still another example of a system to which the antenna device 31 according to the embodiment can be applied. The system in FIG. 23 can feed power to each UE by beamforming from the base station 25 to a plurality of UEs 40. A plurality of UEs 40(1) to 40(3) are located in the WPT area 25A' (see FIG. 21 described above) within the communication area 25A, and each UE communicates via beams 25B(1) to 25B(3) formed by each UE. Power may be supplied to each of the UEs 40(1) to 40(3). The beams 25B(1) to 25B(3) may be formed, for example, by being switched in a time-division manner.

As described above, according to the present embodiment, it is possible to achieve both high antenna gain and a wide directivity angle range in an antenna device that can be used in a power receiving device of a wireless power transmission system and a receiving device of a communication system.

In particular, according to the present embodiment, the phase adjustment between the plurality of antenna units constituting the antenna device is performed using the plurality of connection path lengths of the connection circuits that connect to the plurality of antenna units. A phase control device for controlling the phase is not required, and the configuration of the antenna device can be simplified.

Note that the plurality of connection path lengths (phase adjustment amounts) set for each of the plurality of antenna units may be determined using machine learning. Furthermore, the program used in the antenna device, power receiving device, and receiving device of this embodiment may include a machine learned model.

In addition, the present invention makes it possible to improve the efficiency of wireless power transfer (WPT) to power receiving devices such as IoT devices, so it is possible to improve the efficiency of wireless power transfer (WPT) to power receiving devices such as IoT devices. We can contribute to the achievement of "Let's create something."

Note that the processing steps and the components of the antenna device, power receiving device, receiving device, terminal device, wireless power transmission system, and communication system described in this specification can be implemented by various means. For example, these steps and components may be implemented in hardware, firmware, software, or a combination thereof.

Regarding hardware implementation, means such as processing units used to realize the above steps and components in an entity (e.g., various wireless communication devices, Node B, terminal, hard disk drive device, or optical disk drive device) are: one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors , a controller, a microcontroller, a microprocessor, an electronic device, other electronic unit designed to perform the functions described herein, a computer, or a combination thereof.

Additionally, for firmware and/or software implementations, the means used to implement the components described above, such as processing units, may include programs (e.g., procedures, functions, modules, instructions) that perform the functions described herein. , etc.). In general, any computer/processor readable medium tangibly embodying firmware and/or software code, such as a processing unit, may be used to implement the above steps and components described herein. may be used for implementation. For example, the firmware and/or software code may be stored in memory and executed by a computer or processor, eg, in a controller. The memory may be implemented within the computer or processor, or external to the processor. The firmware and/or software code may also be stored in, for example, random access memory (RAM), read-only memory (ROM), non-volatile random access memory (NVRAM), programmable read-only memory (PROM), electrically erasable PROM (EEPROM), etc. ), flash memory, floppy disks, compact disks (CDs), digital versatile disks (DVDs), magnetic or optical data storage devices, etc. good. The code may be executed by one or more computers or processors and may cause the computers or processors to perform certain aspects of the functionality described herein.

Further, the medium may be a non-temporary recording medium. Further, the code of the program may be read and executed by a computer, processor, or other device or apparatus, and its format is not limited to a specific format. For example, the code of the program may be a source code, an object code, or a binary code, or may be a mixture of two or more of these codes.

The description of the embodiments disclosed herein is also provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the examples and designs described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

10: Wireless power transmission system 20: Power transmission device 21: Antenna device 30: Power receiving device 31: Antenna device 32: Rectifier circuit group 33: DC synthesis circuit 34: Phase adjustment circuit group 35: Synthesis circuit 37: A/D converter group 38: Digital synthesis circuit 39: MIMO signal processing unit 40: Terminal device 45: Receiving device 46: Receiving device 47: Receiving device 310: Array antenna (one-dimensional array antenna)
310(1) to 310(16): Antenna unit 310': Two-dimensional array antenna 310B: Beam 310D: Directional pattern 311: Antenna element 312: Connection circuit 313: Connection line 314: Synthetic connection circuit 321: Rectifier circuit 341: Phase adjustment circuit 371: A/D converter 390: Receiver group 391: Receiver

Claims (18)

A power receiving device used for wireless power transmission,
Equipped with an antenna device, a plurality of rectifier circuits, and a DC combining circuit,
The antenna device includes:
a plurality of antenna units each having a plurality of antenna elements arranged at intervals of 0.5 times or more the wavelength of the radio waves to be received;
a connection circuit having a plurality of connection paths connected to each of the plurality of antenna units with mutually different path lengths so that the angular directions of the directional beams of the plurality of antenna units are different from each other;
The plurality of rectifier circuits are connected to each of the plurality of antenna units via a connection circuit consisting of the plurality of connection paths,
The DC combining circuit combines and outputs a plurality of DC powers output from the plurality of rectifier circuits,
A power receiving device characterized by: In the power receiving device according to claim 1,
The plurality of antenna elements are arranged at intervals of one or more times the wavelength of the radio wave to be received so that the antenna unit has a plurality of directional beams,
The path lengths of the plurality of connection paths are set such that the angular directions of the plurality of directional beams are different from each other among the plurality of antenna units.
A power receiving device characterized by: In the power receiving device according to claim 2,
The plurality of antenna units are arranged such that an antenna element of an antenna unit other than the antenna unit is located between the plurality of antenna elements of the antenna unit.
A power receiving device characterized by: In the power receiving device according to claim 3,
The plurality of antenna elements in the plurality of antenna units are arranged one-dimensionally,
A power receiving device characterized by: In the power receiving device according to claim 3,
The plurality of antenna elements in the plurality of antenna units are two-dimensionally arranged,
A power receiving device characterized by: In the power receiving device according to claim 1,
A power receiving device characterized in that the radio waves to be received are millimeter waves. A wireless power transmission system,
The power receiving device according to any one of claims 1 to 6,
a power transmission device that transmits radio waves for wireless power transmission toward the power receiving device;
A wireless power transmission system comprising: A receiving device used for communication,
Equipped with an antenna device, a plurality of phase adjustment circuits, and a synthesis circuit,
The antenna device includes:
a plurality of antenna units each having a plurality of antenna elements arranged at intervals of 0.5 times or more the wavelength of the radio waves to be received;
a connection circuit having a plurality of connection paths connected to each of the plurality of antenna units with mutually different path lengths so that the angular directions of the directional beams of the plurality of antenna units are different from each other;
The plurality of phase adjustment circuits are connected to each of the plurality of antenna units via a connection circuit consisting of the plurality of connection paths,
The combining circuit combines the plurality of received signals outputted from the plurality of phase adjustment circuits in the same phase and outputs the combined signal.
A receiving device characterized by: A receiving device used for communication,
Comprising an antenna device, a plurality of A/D converters, and a combining circuit,
The antenna device includes:
a plurality of antenna units each having a plurality of antenna elements arranged at intervals of 0.5 times or more the wavelength of the radio waves to be received;
a connection circuit having a plurality of connection paths connected to each of the plurality of antenna units with mutually different path lengths so that the angular directions of the directional beams of the plurality of antenna units are different from each other;
The plurality of A/D converters are connected to each of the plurality of antenna units via a connection circuit consisting of the plurality of connection paths,
The combining circuit performs in-phase combining of the plurality of received signals output from the plurality of A/D converters by digital processing and outputs the resultant signal.
A receiving device characterized by: A receiving device used for communication,
Comprising an antenna device, a plurality of receivers, and a signal processing section,
The antenna device includes:
a plurality of antenna units each having a plurality of antenna elements arranged at intervals of 0.5 times or more the wavelength of the radio waves to be received;
a connection circuit having a plurality of connection paths connected to each of the plurality of antenna units with mutually different path lengths so that the angular directions of the directional beams of the plurality of antenna units are different from each other;
The plurality of receivers are connected to each of the plurality of antenna units via a connection circuit consisting of the plurality of connection paths,
The signal processing unit performs MIMO signal processing on the plurality of received signals output from the plurality of receivers,
A receiving device characterized by: The receiving device according to any one of claims 8 to 10,
The plurality of antenna elements are arranged at intervals of one or more times the wavelength of the radio wave to be received so that the antenna unit has a plurality of directional beams,
The path lengths of the plurality of connection paths are set such that the angular directions of the plurality of directional beams are different from each other among the plurality of antenna units.
A receiving device characterized by: The receiving device according to claim 11,
The plurality of antenna units are arranged such that an antenna element of an antenna unit other than the antenna unit is located between the plurality of antenna elements of the antenna unit.
A receiving device characterized by: The receiving device according to claim 12,
The plurality of antenna elements in the plurality of antenna units are arranged one-dimensionally,
A receiving device characterized by: The receiving device according to claim 12,
The plurality of antenna elements in the plurality of antenna units are two-dimensionally arranged,
A receiving device characterized by: The receiving device according to any one of claims 8 to 10,
A receiving device characterized in that the radio waves to be received are millimeter waves. A receiving device according to any one of claims 8 to 10 ,
a transmitting device that performs wireless communication with the receiving device;
A communication system comprising: A terminal device,
comprising the power receiving device according to any one of claims 1 to 6 or the receiving device according to any one of claims 8 to 10 ,
A terminal device characterized by: The terminal device according to claim 17,
A terminal device characterized in that the terminal device is an IoT device.