Rectenna device and electronic device

Abstract

A rectenna device is provided which is capable of achieving high rectification efficiency over a wide range of input power intensity. A rectenna device comprises: two or more antenna elements; a first rectifier circuit provided for each of the antenna elements, which rectifies one output of the antenna element; and a second rectifier circuit, which can combine and input the outputs of the two or more antenna elements and rectify the combined output. A control is implemented to change the number of antenna elements connected to each of the first and second rectifier circuits.

Description

TECHNICAL AREA

[0001] The present technology relates to a rectenna device and an electronic device. STATE OF THE ART

[0002] As a technical trend in wireless power transmission, three radio bands of 920 MHz, 2.4 GHz, and 5.7 GHz are being used in wireless microwave power transmission in Japan, and a wireless power transmission system using these three bands was legalized in May 2022. Future plans also include the realization of a wireless power transmission system using waves from higher radio bands (for example, a millimeter wave band around 24 GHz or a higher frequency band around 60 GHz). These radio wave bands are also being considered for use in a fifth-generation mobile communication system (so-called 5G), Beyond 5G, 6G, or similar technologies resulting from the development of 5G, and a combination of these communication systems and wireless power transmission is also being explored.As a power supply system that uses wireless power transmission, it is expected to power not only Internet of Things (IoT) devices, but also mobile devices and enable the wireless creation of a Universal Serial Bus (USB). One of the technical elements for realizing wireless power transmission is a rectenna (see, for example, patent document 1). Rectenna is short for rectifying antenna. QUOTES CONTAINED IN THE DESCRIPTION PATENT DOCUMENT

[0003] Patent document 1: Japanese patent application with publication number 2012-139051 SUMMARY OF THE INVENTION PROBLEMS THAT THE INVENTION IS INTENDED TO SOLVE.

[0004] In general, the rectification efficiency of rectennas depends on the properties of the semiconductors, and a problem is that the efficiency decreases rapidly at a certain input power intensity or higher. For this reason, rectennas capable of achieving high rectification efficiency over a wide range of input power intensities are desirable.

[0005] One objective of the present technology is to provide a rectenna device capable of achieving high rectification efficiency over a wide range of input power intensity, and an electronic device incorporating the rectenna device. SOLUTIONS FOR PROBLEMS

[0006] The technology presented here is, for example, a rectenna device that includes the following: two or more antenna elements; a first rectifier circuit provided for each of the antenna elements, which rectifies one output of the antenna element; and a second rectifier circuit that can combine and input the outputs of the two or more antenna elements and rectifies the combined output, wherein A control is performed to change the number of antenna elements connected to each of the first rectifier circuit and the second rectifier circuit.

[0007] The present technology can be an electronic device with the above rectenna device. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a diagram that is referenced when describing a physical background in relation to the technology at hand. Fig. Figure 2 is a diagram that is referenced when describing a physical background in relation to the technology at hand. A and B of Fig. 3 are diagrams that are referenced when describing a physical background in relation to the technology at hand. Fig. Figure 4 is a diagram describing a configuration example of a rectenna device according to a first embodiment. Fig. Figure 5 is a diagram that is referenced when describing an operating example of the rectenna device according to the first embodiment. Fig. Figure 6 is a diagram that is referenced when describing an operating example of the rectenna device according to the first embodiment. Fig. Figure 7 is a diagram that is referenced when describing an example of effects obtained by the rectenna device according to the first embodiment. Fig. Figure 8 is a diagram describing a configuration example of the rectenna device according to a second embodiment. Fig. Figure 9 is a diagram describing a configuration example of a rectenna device according to a third embodiment. Fig. Figure 10 is a diagram describing a configuration example of a rectenna device according to a fourth embodiment. Fig. Figure 11 is a diagram describing a configuration example of a rectenna device according to a fifth embodiment. Fig. Figure 12 is a diagram describing a modification of the rectenna device according to the fifth embodiment. Fig. Figure 13 is a diagram describing a configuration example of a rectenna device according to a sixth embodiment. Fig. Figure 14 is a diagram describing an example of a rectenna device according to a seventh embodiment. Fig. Figure 15 is a diagram describing another example of a rectenna device according to a seventh embodiment. Fig. Figure 16 is a diagram describing a configuration example of a rectenna device according to an eighth embodiment. A and B of Fig. Figure 17 are diagrams describing a configuration example of a rectenna device according to a ninth embodiment. A and B of Fig. Figure 18 are diagrams describing another configuration example of the rectenna device according to the ninth embodiment. A to J of Fig. Figure 19 are diagrams that represent specific examples of an electronic device to which the rectenna device according to the present technology is applicable. Fig. Figure 20 is a diagram that is referenced when describing an operating example of the Rectenna device according to the present technology in a case where the Rectenna device is applied to a smartphone. Fig. Figure 21 is a diagram that is referenced when describing an operating example of the Rectenna device according to the present technology in a case where the Rectenna device is applied to a smartphone. Fig. Figure 22 is a block diagram describing a configuration example of an electronic device to which the rectenna device is applied according to the present technology. Fig. Figure 23 is a block diagram describing a configuration example of a power transmitter, which forms an example of a power transmission and reception system according to the present technology, and an electronic device to which a rectenna device is applied. Fig. Figure 24 is a block diagram to describe a configuration example of a power transmitter, which is another example of a power transmission and reception system according to the present technology, and an electronic device to which a rectenna device is applied. Fig. Figure 25 is a flowchart to describe an example of processing that is carried out between the power transmitter and the electronic device in the power transmission and reception system according to the present technology. Fig. Figure 26 is a diagram used to describe a modification. Fig. Figure 27 is a diagram used to describe a modification. Fig. Figure 28 is a diagram to describe a modification. Fig. Figure 29 is a diagram used to describe a modification. MODES FOR EXECUTING THE INVENTION

[0008] Embodiments and the like of the present technology are described below with reference to the drawings. It should be noted that the embodiments and the like described below are preferred specific examples of the present technology, and the content of the present technology is not limited to these embodiments and the like. It should also be noted that, in some cases, the sizes, positional relationships, and the like of the elements in each of the drawings are exaggerated for the sake of clarity, and there is also a case where only some of the reference numerals are shown or the representation is partially simplified to avoid complicating the description.Furthermore, in the following description, the same names or reference symbols refer to the same or similar elements, and redundant descriptions are omitted in some cases where appropriate.

[0009] The description is given in the following order. [Physical background] [First embodiment] [Second embodiment] [Third embodiment] [Fourth embodiment] [Fifth embodiment] [Sixth embodiment] [Seventh embodiment] [Eighth embodiment] [Ninth embodiment] [Application example] [Modification] [Physical background]

[0010] First, a physical background of the present technology will be explained with reference to the Fig. 1 to Fig. 3 described to facilitate understanding of the technology at hand.

[0011] Fig. Figure 1 is a diagram describing a configuration example of a general rectenna device (Rectenna Device 1). Rectenna Device 1 includes, for example, an antenna element 2 and a rectifier circuit 3. Rectenna Device 1 may also include a matching network (not shown) and the like, as needed. A suitable load 4 is connected to the rectifier circuit 3. Examples of load 4 include a battery, a communication device, a sensor, a motor, and the like. Rectenna Device 1 can generally be applied to an electronic device that includes the load 4.

[0012] In the rectenna device 1, the antenna element 2 receives electromagnetic wave energy (hereinafter also simply referred to as electromagnetic waves) in space. The antenna element 2 outputs alternating current (AC) power to the rectifier circuit 3. The rectifier circuit 3 rectifies the alternating current supplied by the antenna element 2, converts the AC power into DC power, and outputs the DC power to the load 4.

[0013] Fig. Figure 2 is a graph illustrating the rectification efficiency of the rectenna device 1. In the graph of Fig. Figure 2 shows the horizontal axis representing the input power (dBm), and the vertical axis representing the rectification efficiency (%). The rectification efficiency of the rectenna device 1 is defined as the ratio of the DC power output by the rectenna device 1 to the power of the electromagnetic waves input into the antenna element 2. As shown in Figure 2, the rectenna efficiency is calculated as follows: Fig. As illustrated in Figure 2, in the rectenna device 1, the rectification efficiency gradually increases from a region where the input power is small, but due to the breakdown voltage of the semiconductor element, the rectification efficiency decreases rapidly in a region where the input power is greater than a certain value (for example, about -5 dBm). Factors that cause the input power (energy of the electromagnetic wave) to fluctuate include a case where the distance between the power transmission side and the rectenna device fluctuates, a case where a power transmitter with varying output power is used, and the like.

[0014] As in Fig. Figure 3A illustrates that in a case where an antenna element 2 is used, power is output over a relatively wide range. On the other hand, as shown in Fig. Figure 3B illustrates a case where a large number of antenna elements 2 are arranged in an array and designed such that radio waves are emitted by the antenna elements 2 with the same phase, resulting in high power output in a specific direction (for example, the forward direction). Even when considered as a power receiving side, it is possible to receive power for a similar reason, even if the power from the forward direction is low. In a high band such as the millimeter wave, such a technique of arranging antenna elements 2 in an array is expected to be commonly used. That is, a rectenna device capable of achieving the highest possible rectification efficiency over a wide range of input power while using a large number of antenna elements is desirable.Based on the above points, details of the present technology are described with reference to embodiments. [First embodiment](Configuration example of a rectenna device)

[0015] Fig. Figure 4 is a diagram describing a configuration example of a rectenna device (Rectenna Device 100A) according to a first embodiment. The Rectenna Device 100A is a rectenna device that incorporates two or more antenna elements (in Fig. 4 referred to as “ANT”), comprising a first rectifier circuit provided for each antenna element and rectifying one output of the antenna element, and a second rectifier circuit that can combine and input the outputs of the two or more antenna elements and rectifies the combined output, wherein control is performed to change the number of antenna elements connected to each of the first rectifier circuit and the second rectifier circuit.

[0016] The Rectenna device 100A, for example, includes an antenna element 10A, an antenna element 10B, a switching unit (in Fig. 4 (referred to as "SW") 11A, a switching unit 11B, a rectifier circuit 12A, a rectifier circuit 12B, a rectifier circuit 20, a switching unit 21, a control unit 40, and an output parameter acquisition unit 41. The rectenna device 100A is connected to a load 30, and the DC power generated by the rectenna device 100A is supplied to the load 30. The load 30 can be represented by a load similar to the load 4 described above.

[0017] Antenna element 10A is a patch antenna, a dipole antenna, a loop antenna, or the like. Antenna element 10A outputs a high-frequency signal (RFA) as AC power by receiving electromagnetic waves in space. It should be noted that the present description presents an example in which a high-frequency signal is transmitted differentially (a thick dotted line and a thick solid line in the diagram). Fig. 4), but the present technology is also applicable to asymmetric transmission.

[0018] The switching unit 11A is connected to the output stage (subsequent stage) of the antenna element 10A. The switching unit 11A is a switch that selects the supply destination of the high-frequency signal RFA output by the antenna element 10A. In particular, the switching unit 11A can be connected to the rectifier circuit 12A and the rectifier circuit 20 and switches the supply destination of the high-frequency signal RFA to either the rectifier circuit 12A or the rectifier circuit 20.

[0019] Rectifier circuit 12A is connected to the output stage of switching unit 11A. When the high-frequency signal RFA is supplied via switching unit 11A, rectifier circuit 12A receives direct current (DC) power DCA by rectifying the RFA signal. Rectifier circuit 12A outputs the DC power DCA to switching unit 21. It should be noted that in this description, the DC power is represented by two lines: positive and negative (thin dotted line and solid line in [reference]). Fig. 4) is specified, but may be specified by a power transmission line.

[0020] The DC power DCA output by rectifier circuit 12A is supplied to switching unit 21. Rectifier circuit 12A can be configured as an integrated circuit (IC). Any known rectifier circuit can be used as rectifier circuit 12A. For example, a bridge rectifier, a voltage doubler, a single shunt rectifier, or the like can be used as rectifier circuit 12A. The semiconductor component used in these rectifier circuits is optional. Examples of semiconductor components include a Schottky blocking diode, a complementary metal oxide semiconductor (CMOS), a high electron mobility transistor (HEMT), or the like.

[0021] Antenna element 10B is a patch antenna, a dipole antenna, a loop antenna, or the like. Antenna element 10B receives electromagnetic waves in space to output a high-frequency signal (RFB) as AC power. Antenna element 10A and antenna element 10B are, for example, arranged two-dimensionally on the same substrate. The present embodiment is an example in which antenna element 10A and antenna element 10B are connected in parallel.

[0022] The switching unit 11B is connected to the output stage of the antenna element 10B. The switching unit 11B is a switch that selects the supply destination of the high-frequency signal RFB output by the antenna element 10B. In particular, the switching unit 11B can be connected to the rectifier circuit 12B and the rectifier circuit 20 and switches the supply destination of the high-frequency signal RFB to either the rectifier circuit 12B or the rectifier circuit 20.

[0023] Rectifier circuit 12B is connected to the output stage of switching unit 11B. When the high-frequency signal RFB is supplied via switching unit 11B, rectifier circuit 12B receives DC power DCB by rectifying the high-frequency signal RFB. Rectifier circuit 12B outputs the DC power DCB to switching unit 21.

[0024] The DC power DCB output by the rectifier circuit 12B is supplied to the switching unit 21. The rectifier circuit 12B can be configured as an integrated circuit. Any known rectifier circuit can be used as the rectifier circuit 12B. For example, a bridge rectifier, a voltage doubler, a single shunt rectifier, or the like can be used as the rectifier circuit 12B. The semiconductor component used in these rectifier circuits is optional. Examples of semiconductor components include a Schottky blocking diode, a CMOS chip, a HEMT, or the like.

[0025] The rectifier circuit 20 is connected to the output stages of switching unit 11A and switching unit 11B. When the high-frequency signal RFA is supplied via switching unit 11A and the high-frequency signal RFB is supplied via switching unit 11B, the rectifier circuit 20 receives DC power DCW by rectifying a high-frequency signal RFW obtained by combining the high-frequency signal RFA and the high-frequency signal RFB. The rectifier circuit 20 outputs the DC power DCW to switching unit 21.

[0026] The DC power DCW output by the rectifier circuit 20 is supplied to the switching unit 21. The rectifier circuit 20 can be configured as an integrated circuit. Any known rectifier circuit can be used as the rectifier circuit 20. For example, a bridge rectifier, a voltage doubler, a single shunt rectifier, or the like can be used as the rectifier circuit 20. The semiconductor component used in these rectifier circuits is optional. Examples of semiconductor components include a Schottky blocking diode, a CMOS chip, a HEMT, or the like.

[0027] A switching unit SW21 is connected to the output stages of rectifier circuit 12A, rectifier circuit 12B, and rectifier circuit 20. Switching unit SW21 is a switch that controls the DC power supplied to load 30. When DC power DCA is supplied by rectifier circuit 12A and DC power DCB is supplied by rectifier circuit 12B, switching unit SW21 outputs the DC power obtained by combining DC power DCA and DC power DCB to load 30. Additionally, when DC power DCW is supplied by rectifier circuit 20, switching unit SW21 outputs the DC power DCW to load 30.

[0028] The control unit 40 comprises a central processing unit (CPU) and the like, and controls the Rectenna device 100A integrally. For example, the control unit 40 outputs a switching signal to control the switching of switching unit 11A, switching unit 11B, and switching unit 21. The operations of switching unit 11A, switching unit 11B, and switching unit 21 are controlled by the switching control provided by the control unit 40.

[0029] The output parameter acquisition unit 41 acquires an output parameter corresponding to the input power into the antenna element. The antenna element can be either antenna element 10A or antenna element 10B; however, it is assumed that antenna element 10A and antenna element 10B are located close to each other. That is, given that there is no significant difference in the input power to the two antenna elements, the output parameter acquisition unit 41 can acquire the output parameter corresponding to the input power into either antenna element 10A or antenna element 10B.

[0030] In the present embodiment, the magnitude of the DC power output from at least one rectifier circuit is detected as an example of an output parameter corresponding to the input power to the antenna element. When the input power to the antenna element is high, the DC power output from the rectifier circuit increases, and when the input power to the antenna element is low, the DC power output from the rectifier circuit decreases. As described above, since the DC power output from the rectifier circuit changes according to the input power to the antenna element, the magnitude of the DC power output from the rectifier circuit can be used as the output parameter. In the present embodiment, the output parameter detection unit 41 detects the DC power DCA output by the rectifier circuit 12A as an output parameter.The output parameter acquisition unit 41 delivers the acquisition result to the control unit 40.

[0031] It should be noted that the functions of the control unit 40 and the output parameter acquisition unit 41 can be performed not by the Rectenna device 100A, but by a CPU or the like of an electronic device to which the Rectenna device 100A is applied.

[0032] In the present embodiment, rectifier circuit 12A and rectifier circuit 12B correspond to an example of the first rectifier circuit provided for each antenna element. Furthermore, rectifier circuit 20 corresponds to an example of the second rectifier circuit, which can combine and input the outputs of antenna element 10A and antenna element 10B and rectify the combined output. It should be noted that the three rectifier circuits can have different circuit configurations, but in the present technology, it is also possible to use rectifier circuits with the same circuit configuration. As a result, a reduction in cost and a simplification of the manufacturing process of the Rectenna device 100A can be achieved. (Operating example of the rectenna device)

[0033] Next, an operating example of the Rectenna device 100A according to the present embodiment is described. Schematically, in a case where the input power to antenna element 10A and antenna element 10B is high, the output of each antenna element is fed to the first rectifier circuit provided for each antenna element. In a case where the input power to antenna element 10A and antenna element 10B is low, the outputs of the antenna elements are combined and fed to the second rectifier circuit. The control unit 40 determines whether the input voltage is high or low based on the detection result of the output parameter detection unit 41.

[0034] Details of the operating example are described below. The output parameter acquisition unit 41 delivers the acquisition result of the DC power DCA, which is output by the rectifier circuit 12A, to the control unit 40.

[0035] The control unit 40 determines that the input voltage to the antenna element 10A and the antenna element 10B is large in a case where the magnitude of the DC power DCA is equal to or greater than a predetermined threshold, and determines that the input voltage to the antenna element 10A and the antenna element 10B is small in a case where the magnitude of the DC power DCA is less than the predetermined threshold.It should be noted that in the following description, a case in which the magnitude of the DC power DCA is equal to or greater than the predetermined threshold and the input voltage to antenna element 10A and antenna element 10B is determined to be large is appropriately referred to as a large input power time, and a case in which the magnitude of the DC power DCA is less than the predetermined threshold and the input voltage to antenna element 10A and antenna element 10B is determined to be small is appropriately referred to as a small input power time.

[0036] During the high input power period, the control unit 40 controls the Rectenna device 100A to operate in a high input power mode. Specifically, it controls, as shown in Fig. As shown in Figure 5, the control unit 40 controls the switching unit 11A, so that the high-frequency signal RFA (RF: radio frequency) output by the antenna element 10A is fed to the rectifier circuit 12A. Additionally, as shown in Figure 5, the control unit 40 controls the switching unit 11A. Fig. As shown in Figure 5, the control unit 40 controls the switching unit 11B, so that the high-frequency signal RFB output by the antenna element 10B is fed to the rectifier circuit 12B. Then the control unit 40 controls the switching unit 21, so that DC power (an example of a first output), obtained by combining the DC power DCA output by the rectifier circuit 12A and the DC power DCB output by the rectifier circuit 12B, is supplied to the load 30.

[0037] During the low input power period, the control unit 40 controls the Rectenna device 100A to operate in a low input power operating mode.

[0038] In particular, it controls, as in Fig. As shown in Figure 6, the control unit 40 controls the switching unit 11A, so that the high-frequency signal RFA output by the antenna element 10A is fed to the rectifier circuit 20. Additionally, as shown in Figure 6, the control unit 40 controls the switching unit 11A, so that the high-frequency signal RFA output by the antenna element 10A is fed to the rectifier circuit 20. Fig. As shown in Figure 6, the control unit 40 controls the switching unit 11B, so that the high-frequency signal RFB output by the antenna element 10B is fed to the rectifier circuit 20. As a result, the high-frequency signal RFW, obtained by combining the high-frequency signal RFA and the high-frequency signal RFB, is fed to the rectifier circuit 20. Then the control unit 40 controls the switching unit 21, so that the DC power DCW (an example of a second output), obtained by rectifying the high-frequency signal RFW through the rectifier circuit 20, is supplied to the load 30.

[0039] By performing the above control, during the low input power period, the number of antenna elements connected to rectifier circuit 12A is "0", the number of antenna elements connected to rectifier circuit 12B is "0", and the number of antenna elements connected to rectifier circuit 20 is "2". Furthermore, during the high input power period, the number of antenna elements connected to rectifier circuit 12A is "1", the number of antenna elements connected to rectifier circuit 12B is "1", and the number of antenna elements connected to rectifier circuit 20 is "0".

[0040] This means that in a case where the magnitude of the DC power DCA is less than the predetermined threshold (in a case where the output parameter is a first output parameter), control is carried out so that the number of antenna elements connected to each of the rectifier circuit 12A and the rectifier circuit 12B is less than that during the large input power time, and the number of antenna elements connected to the rectifier circuit 20 is greater than that during the large input power time.Meanwhile, if the magnitude of the DC power DCA is equal to or greater than the predetermined threshold (in a case where the output parameter is a second output parameter), a control is performed such that the number of antenna elements connected to each of rectifier circuit 12A and rectifier circuit 12B is greater than during the low input power period, and the number of antenna elements connected to rectifier circuit 20 is less than during the low input power period. As a result, the number of antenna elements connected to each of rectifier circuit 12A and rectifier circuit 12B, and the number of antenna elements connected to rectifier circuit 20, are changed.As described above, in the present embodiment the number of antenna elements connected to each of the first rectifier circuit and the second rectifier circuit is changed according to the output parameter, which corresponds to the input power into the antenna element. (Effects obtained through the present embodiment)

[0041] The effects obtained by the present embodiment are described with reference to Fig. 7 described.

[0042] In the Fig. In the illustrated graph 7, the horizontal axis represents the input power (dBm), and the vertical axis represents the rectification efficiency (%). A line L1 in Fig. Figure 7 indicates the rectification efficiency of the Rectenna device 100A in a case of operation in the low input power operating mode, and a line L2 in Fig. Figure 7 indicates the rectification efficiency of the Rectenna device 100A in a case of operation in the operating mode with high input power.

[0043] For example, based on the input power corresponding to a crossing point CP where lines L1 and L2 intersect, a threshold is set to identify the high input power time and the low input power time. As a result, the operating mode of the Rectenna 100A device is switched to high input power mode at the point where the input power increases and the rectification efficiency begins to decrease on line L1 (the point near crossing point CP), so that the decrease in rectification efficiency, as indicated by line L2, can be suppressed.Additionally, by switching the operating mode of the Rectenna 100A device to the low-input-power mode, it is possible to suppress the decrease in rectification efficiency, as indicated by line L1, at the point where the input power decreases and the rectification efficiency begins to decline on line L2 (the part near the intersection point CP). This means that even in a case where the input voltage to the Rectenna 100A device fluctuates, it is possible to implement a Rectenna 100A device capable of achieving high rectification efficiency across a wide range of input power intensities. (Modification of the first embodiment)

[0044] In the description above, the output parameter acquisition unit 41 detects the magnitude of the DC power DCA output by the rectifier circuit 12A. However, the output parameter acquisition unit 41 can also detect the magnitude of the DC power DCB output by the rectifier circuit 12B. Alternatively, the output parameter acquisition unit 41 can detect the magnitude of the DC power DCW output by the rectifier circuit 20. Additionally, the output parameter acquisition unit 41 can detect the outputs of a variety of rectifier circuits, such as the magnitude of the DC power DCA output by the rectifier circuit 12A and the magnitude of the DC power DCB output by the rectifier circuit 12B.However, since the antenna element 10A and the antenna element 10B are arranged relatively close to each other, and considering that there is no large difference in the magnitude of the input power, it is preferable, from a cost point of view, that the output parameter detection unit 41 detects the output of one of the rectifier circuits 12A and 12B.

[0045] The output parameter acquired by the output parameter acquisition unit 41 need not be DC power output by the rectifier circuit 12A or the like, and can be a DC voltage, DC current, or impedance of the rectifier circuit 12A or the like. Since these DC voltages and the like are also values ​​that change according to the input power to the antenna element, they can also be used as output parameters. Furthermore, the output parameter can be a parameter related to the load 30. In a case where the load 30 is a motor, the motor's speed can be specified as a parameter related to the load 30. For example, the motor's speed is maintained during periods of high input power and decreases during periods of low input power.This means that since the value changes according to the input power to the antenna element, the motor speed can also be used as the output parameter. In this case, the motor speed is fed back from the load 30 to the Rectenna device 100A, and the output parameter acquisition unit 41 detects the fed-back motor speed to determine the motor's speed. The output parameter acquisition unit 41 then outputs the acquisition result to the control unit 40. Based on the motor speed supplied by the output parameter acquisition unit 41, the control unit 40 can determine whether the input power to the antenna element is high or low.In a case where the load 30 is a light-emitting diode (LED), the LED's light emission intensity, the signal level passing through the LED, and similar parameters can also be used as load-related parameters. Additionally, instead of a single output parameter, a combination of the output parameters illustrated above can be used. [Second embodiment]

[0046] A second embodiment is described next. It should be noted that in the description of the second embodiment, the same or similar configurations as in the preceding description are designated by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the aspects (configurations, effects, and the like) described in other embodiments may be applied to the second embodiment unless otherwise stated.

[0047] Fig. Figure 8 is a diagram describing a configuration example of a rectenna device (Rectenna Device 100B) according to the second embodiment. The present embodiment is one in which a first rectifier circuit and a second rectifier circuit have a common configuration.

[0048] Rectenna device 100B differs from Rectenna device 100A in that the switching unit 11A is not provided and a high-frequency signal RFA, which is the output of an antenna element 10A, is always fed to a rectifier circuit 12A, and that the rectifier circuit 20 is not provided and the output of a switching unit 11B can be fed to the rectifier circuit 12A. That is to say, in the present embodiment, the rectifier circuit 12A has a configuration common to the rectifier circuit 20 in the first embodiment.

[0049] The operating procedure in a case where the Rectenna device 100B operates in high-input mode is essentially the same as that of the Rectenna device 100A. That is, during the high-input-power period, the high-frequency signal RFA output by the antenna element 10A is fed to the rectifier circuit 12A. Additionally, the control unit 40 controls a switching unit 11B, so that a high-frequency signal RFB output by an antenna element 10B is fed to a rectifier circuit 12B. Then, DC power obtained by combining DC power DCA, obtained by rectifying the high-frequency signal RFA through the rectifier circuit 12A, and DC power DCB, obtained by rectifying the high-frequency signal RFB through the rectifier circuit 12B, is supplied to a load 30.

[0050] During periods of low input power, that is, when the Rectenna device 100B is operating in low input power mode, the control unit 40 controls the switching unit 11B, so that the high-frequency signal RFB is fed to the rectifier circuit 12A. As a result, in the input stage (preceding stage) of the rectifier circuit 12A, the high-frequency signal RFA and the high-frequency signal RFB are combined to generate a high-frequency signal RFW. Then, DC power DCW, obtained by rectifying the high-frequency signal RFW through the rectifier circuit 12A, is supplied to the load 30.

[0051] By performing the above control, during the low input power period, the number of antenna elements connected to rectifier circuit 12A is "2" and the number of antenna elements connected to rectifier circuit 12B is "0". Meanwhile, during the high input power period, the number of antenna elements connected to rectifier circuit 12A is "1" and the number of antenna elements connected to rectifier circuit 12B is "1".

[0052] The Rectenna device 100B of the present embodiment can also achieve effects similar to those of the first embodiment. In addition, according to the present embodiment, since the number of rectifier circuits can be reduced, the cost of the Rectenna device 100B can be reduced.

[0053] It should be noted that in the present embodiment the rectifier circuit 12A and the rectifier circuit 20 have a common configuration, but the rectifier circuit 12B and the rectifier circuit 20 can have a common configuration. [Third embodiment]

[0054] Next, a third embodiment is described. It should be noted that in the description of the third embodiment, the same or similar configurations in the preceding description are designated by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the aspects (configurations, effects, and the like) described in other embodiments may be applied to the third embodiment unless otherwise specified.

[0055] Fig. Figure 9 is a diagram describing a configuration example of a rectenna device (Rectenna Device 100C) according to the third embodiment.

[0056] The Rectenna device 100C has a configuration in which an antenna element 10C, a switching unit 11C connected to the output stage of the antenna element 10C, a rectifier circuit 12C connected to the output stage of the switching unit 11C, an antenna element 10D, a switching unit 11D connected to the output stage of the antenna element 10D, and a rectifier circuit 12D connected to the output stage of the switching unit 11D are further added to the configuration of the Rectenna device 100A. The output stage of the switching unit 11C and the output stage of the switching unit 11D are also connected to a rectifier circuit 20. In the present embodiment, a rectifier circuit 12A, a rectifier circuit 12B, the rectifier circuit 12C, and the rectifier circuit 12D correspond to an example of the first rectifier circuit.Additionally, rectifier circuit 20 corresponds to an example of the second rectifier circuit. Furthermore, a wiring derived from rectifier circuit 12A, rectifier circuit 12B, rectifier circuit 12C, and rectifier circuit 12D is connected such that four antenna elements (antenna element 10A, antenna element 10B, antenna element 10C, and antenna element 10D) are connected in parallel.

[0057] A high-frequency signal RFC is output by antenna element 10C, which has received electromagnetic waves. The rectifier circuit 12C receives DC power DCC by rectifying the RFC signal. Additionally, a high-frequency signal RFD is output by antenna element 10D, which has received electromagnetic waves. The rectifier circuit 12D receives DC power DCD by rectifying the RFD signal.

[0058] An output parameter acquisition unit 41 acquires the DC power DCA output by the rectifier circuit 12A and transmits the acquisition result to a control unit 40. Based on the acquisition result from the output parameter acquisition unit 41, the control unit 40 determines whether the input power to each antenna element is high or low. The control unit 40 then controls each unit of the rectenna device 100C to operate in a mode corresponding to the determination result. It should be noted that the output parameter acquisition unit 41 can acquire the DC power DCB output by the rectifier circuit 12B, the DC power DCC output by the rectifier circuit 12C, or the DC power DCD output by the rectifier circuit 12D.

[0059] An operating example of the Rectenna device 100C is described. In a case where the Rectenna device 100C operates in high-input mode, the control unit 40 controls a switching unit 11A so that a high-frequency signal RFA output by antenna element 10A is fed to the rectifier circuit 12A. Additionally, the control unit 40 controls a switching unit 11B so that a high-frequency signal RFB output by antenna element 10B is fed to a rectifier circuit 12B. Additionally, the control unit 40 controls a switching unit 11C so that a high-frequency signal RFC output by antenna element 10C is fed to the rectifier circuit 12C. Additionally, the control unit 40 controls a switching unit 11D so that a high-frequency signal RFD output by antenna element 10D is fed to a rectifier circuit 12D.Then the control unit 40 controls the switching unit 21 so that DC power, obtained by combining the DC power DCA output by the rectifier circuit 12A, the DC power DCB output by the rectifier circuit 12B, the DC power DCC output by the rectifier circuit 12C, and the DC power DCD output by the rectifier circuit 12D, is supplied to a load 30.

[0060] During the short input power period, the control unit 40 controls the switching unit 11A, so that the high-frequency signal RFA output by the antenna element 10A is fed to the rectifier circuit 20. Additionally, the control unit 40 controls the switching unit 11B, so that the high-frequency signal RFB output by the antenna element 10B is fed to the rectifier circuit 20. Additionally, the control unit 40 controls the switching unit 11C, so that the high-frequency signal RFC output by the antenna element 10C is fed to the rectifier circuit 20. Additionally, the control unit 40 controls the switching unit 11D, so that the high-frequency signal RFD output by the antenna element 10D is fed to the rectifier circuit 20. As a result, the high-frequency signals RFA, RFB, RFC, and RFD are combined at the input stage of the rectifier circuit 20.Then, a high-frequency signal RFP, which is the combined high-frequency signal, is fed to the rectifier circuit 20. The control unit 40 then controls a switching unit 21, so that DC power DCP, obtained by rectifying the high-frequency signal RFP through the rectifier circuit 20, is supplied to the load 30.

[0061] By performing the above control, when the Rectenna device 100C is operating in low input power mode, the number of antenna elements connected to rectifier circuit 12A is “0”, the number of antenna elements connected to rectifier circuit 12B is “0”, the number of antenna elements connected to rectifier circuit 12C is “0”, the number of antenna elements connected to rectifier circuit 12D is “0”, and the number of antenna elements connected to rectifier circuit 20 is “4”.Additionally, when the Rectenna device 100C operates in high input power mode, the number of antenna elements connected to rectifier circuit 12A is "1", the number of antenna elements connected to rectifier circuit 12B is "1", the number of antenna elements connected to rectifier circuit 12C is "1", the number of antenna elements connected to rectifier circuit 12D is "1", and the number of antenna elements connected to rectifier circuit 20 is "0". As a result, the number of antenna elements connected to each of rectifier circuits 12A, 12B, 12C, and 12D, and the number of antenna elements connected to rectifier circuit 20, are modified according to the operating mode of the Rectenna device 100C.

[0062] The rectenna device 100C of the present embodiment can also achieve effects similar to those of the first embodiment. Furthermore, according to the present embodiment, although the number of rectifier circuits is increased, the transmission line length (wiring length) required to transmit a high-frequency signal from each antenna element can be shortened by arranging the rectifier circuit 20 in a suitable position. That is, the wiring layout on the substrate can be simplified, and interference with other wiring (for example, communication wiring) can be suppressed as much as possible. [Fourth embodiment]

[0063] Next, a fourth embodiment is described. It should be noted that in the description of the fourth embodiment, the same or similar configurations in the preceding description are designated by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the aspects (configurations, effects, and the like) described in other embodiments may be applied to the fourth embodiment unless otherwise specified.

[0064] Fig. Figure 10 is a diagram describing a configuration example of a rectenna device (rectenna device 100D) according to the fourth embodiment.

[0065] The Rectenna device 100D differs from the Rectenna device 100C in that a rectifier circuit 12C has a configuration common to the rectifier circuit 20, that there is no rectifier circuit 20 and that there is no switching unit 21.

[0066] The operation of the Rectenna device 100D in high-input mode is essentially the same as that of the Rectenna device 100C. That is, during the high-input-power period, a control unit 40 controls a switching unit 11A, so that a high-frequency signal RFA output by an antenna element 10A is fed to a rectifier circuit 12A. Additionally, the control unit 40 controls a switching unit 11B, so that a high-frequency signal RFB output by an antenna element 10B is fed to a rectifier circuit 12B. Additionally, the control unit 40 controls a switching unit 11C, so that a high-frequency signal RFC output by an antenna element 10C is fed to a rectifier circuit 12C. In addition, the control unit 40 controls a switching unit 11D, so that a high frequency signal RFD output by an antenna element 10D is fed to a rectifier circuit 12D.Then, DC power obtained by combining DC power DCA, obtained by rectifying the high-frequency signal RFA through rectifier circuit 12A, DC power DCB, obtained by rectifying the high-frequency signal RFB through rectifier circuit 12B, DC power DCC, obtained by rectifying the high-frequency signal RFC through rectifier circuit 12C, and DC power DCD, obtained by rectifying the high-frequency signal RFD through rectifier circuit 12D, is supplied to a load 30.

[0067] When the Rectenna device 100D operates in low-input-power mode, the control unit 40 controls the switching unit 11A, so that the high-frequency signal RFA is fed to the rectifier circuit 12C. Additionally, the control unit 40 controls the switching unit 11B, so that the high-frequency signal RFB is fed to the rectifier circuit 12C. Furthermore, the control unit 40 controls the switching unit 11C, so that the high-frequency signal RFC is fed to the rectifier circuit 12C via a path that differs from the one used during high-input-power operation. Finally, the control unit 40 controls the switching unit 11D, so that the high-frequency signal RFD is fed to the rectifier circuit 12D. As a result, the high-frequency signals RFA, RFB, RFC, and RFD are combined in the input stage of the rectifier circuit 12C to generate a high-frequency signal RFP.Then, DC power DCP, obtained by rectifying the high-frequency signal RFP through the rectifier circuit 12C, is supplied to the load 30.

[0068] By performing the above control, when the Rectenna device 100D is operating in low input power mode, the number of antenna elements connected to rectifier circuit 12C is "4", and the number of antenna elements connected to each of rectifier circuits 12A, 12B, and 12D is "0". Meanwhile, when the Rectenna device 100D is operating in high input power mode, the number of antenna elements connected to rectifier circuit 12A is "1", the number of antenna elements connected to rectifier circuit 12B is "1", the number of antenna elements connected to rectifier circuit 12C is "1", and the number of antenna elements connected to rectifier circuit 12D is "1".

[0069] The Rectenna device 100D of the present embodiment can also achieve effects similar to those of the first embodiment. In addition, according to the present embodiment, since the number of rectifier circuits can be reduced, the cost of the Rectenna device 100D can be reduced.

[0070] It should be noted that in the present embodiment the rectifier circuit 12C and the rectifier circuit 20 have a common configuration, but any one of the rectifier circuits 12A, 12B and 12D may have a configuration common to the rectifier circuit 20.

[0071] It should be noted that, although the switching unit 11C can be omitted, in the present embodiment, the path through which the RFC signal is supplied to the rectifier circuit 12C during the long input power operating time and the path through which the RFC signal is supplied to the rectifier circuit 12C during the short input power operating time are separate paths. For example, the transmission line length of the path through which the RFC signal is supplied to the rectifier circuit 12C during the short input power operating time is set to be longer than the transmission line length of the path through which the RFC signal is supplied to the rectifier circuit 12C during the long input power operating time.Consequently, since the latter transmission line length can be adjusted, the transmission line length can easily be set so that the phases of the output from each antenna and the input to the rectifier circuit 20 are essentially the same. It should be noted that a specific example of phase matching will be described later. [Fifth embodiment]

[0072] Next, a fifth embodiment is described. It should be noted that in the description of the fifth embodiment, the same or similar configurations as in the preceding description are designated by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the aspects (configurations, effects, and the like) described in other embodiments may be applied to the fifth embodiment unless otherwise specified.

[0073] Fig. Figure 11 is a diagram describing a configuration example of a rectenna device (rectenna device 100E) according to the fifth embodiment.

[0074] The configuration and operation of the Rectenna device 100E are essentially the same as those of the Rectenna device 100C described in the third embodiment. The difference lies in the connection configuration of the four antenna elements. As in Fig. As shown in Figure 11, in the present embodiment a wiring system derived from a rectifier circuit 12A, a rectifier circuit 12B, a rectifier circuit 12C, and a rectifier circuit 12D is connected such that the connection configuration of four antenna elements (antenna element 10A, antenna element 10B, antenna element 10C, and antenna element 10D) is two in series and two in parallel. As described above, the connection configuration of a plurality of antenna elements can be suitably modified.

[0075] The Rectenna device 100E of the present embodiment can also achieve effects similar to those of the first embodiment. Additionally, in the present embodiment, since the number of antenna elements connected in series is equal to the number of antenna elements connected in parallel, the advantage of a simpler design can be gained.

[0076] It should be noted that, as in Fig. Figure 12 illustrates that, in the Rectenna device 100E, as described in the third embodiment, for example the rectifier circuit 12C and the rectifier circuit 20 can have a common configuration. [Sixth embodiment]

[0077] Next, a sixth embodiment is described. It should be noted that in the description of the sixth embodiment, the same or similar configurations in the preceding description are designated by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the aspects (configurations, effects, and the like) described in other embodiments may be applied to the sixth embodiment unless otherwise specified.

[0078] Fig. Figure 13 is a diagram describing a configuration example of a rectenna device (Rectenna Device 100F) according to the sixth embodiment. The present embodiment is an example of a rectenna device in which the connection type of antenna elements is variable.

[0079] The Rectenna device 100F has a configuration in which a connection mode switching unit 51A, a connection mode switching unit 51B, a connection mode switching unit 52A and a connection mode switching unit 52B are added to the Rectenna device 100C described in the third embodiment (see Fig. 9) will be added.

[0080] As in Fig. As shown in Figure 13, the connection mode switching unit 51A is provided between the output stage of a rectifier circuit 12A and the output stage of a rectifier circuit 12C. Meanwhile, the connection mode switching unit 51B is provided between the output stage of a rectifier circuit 12B and the output stage of a rectifier circuit 12D. Furthermore, the connection mode switching unit 52A is provided between the output stage of a switching unit 11A and the output stage of a switching unit 11B. Meanwhile, the connection mode switching unit 52B is provided between the output stage of a switching unit 11C and the output stage of a switching unit 11D.

[0081] In the present embodiment, for example, the connection mode of the four antenna elements can be switched between a four-parallel connection and a two-row, two-parallel connection. When the connection mode of the four antenna elements is set to a four-parallel connection, each connection mode switching unit operates to adjust the connection mode. Fig. 10. To form the connection shown. In the case of setting the connection mode of the four antenna elements to a two-parallel-two-row connection, each connection mode switch unit works to form the connection shown. Fig. To form the connection shown in section 11.

[0082] It should be noted that in each connection mode switch unit, the switch can be automatically switched according to the switching control of a control unit 40, or the switch can be manually switched.

[0083] The Rectenna device 100F of the present embodiment can also achieve effects similar to those of the first embodiment. Additionally, depending on a load 30, reflection between the load 30 and the Rectenna device 100F can be suppressed by changing the connection mode of the antenna elements and the voltage output of a switching unit 21, thus achieving high efficiency of the Rectenna device 100F. Since there is a load value that optimizes efficiency through the wiring configuration of the Rectenna device 100F, it is also possible to adjust the load and reduce reflection by appropriately changing the connection mode of the antenna element. Furthermore, the optimal load value fluctuates in cases where an application, such as battery charging, is considered.Therefore, by appropriately changing the connection mode of the antenna elements, the output of the Rectenna device 100F can be adapted to the fluctuation of the load value. [Seventh embodiment]

[0084] Next, a seventh embodiment is described. It should be noted that in the description of the seventh embodiment, the same or similar configurations in the preceding description are designated by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the aspects (configurations, effects, and the like) described in other embodiments may be applied to the seventh embodiment unless otherwise specified.

[0085] In each of the embodiments described above, when the Rectenna device is operating in low-power mode, the high-frequency signals output by the antenna elements are combined and fed to a second rectifier circuit (for example, rectifier circuit 20 or a rectifier circuit with a configuration common to rectifier circuit 20). If the transmission line length for transmitting the high-frequency signal to the second rectifier circuit becomes long, the impedance becomes non-negligible. The present embodiment addresses this issue.

[0086] In a rectenna device (rectenna device 100G) according to the present embodiment, the phase of the output from each antenna element and the phase of the input to the second rectifier circuit (for example, rectifier circuit 20) are essentially the same phase (the phase difference is an integer multiple of approximately 360 degrees). One method for achieving this configuration is to adjust the transmission line length between each antenna element and the second rectifier circuit. For example, as in the rectenna device 100D described above (see Figure 100D), the transmission line length is adjusted accordingly. Fig. 10), it is possible to adjust the transmission line length by intentionally increasing the length of the transmission line over which the high-frequency signal RFC is transmitted during the small input power time and to achieve impedance matching by appropriately adjusting the transmission line length.

[0087] Furthermore, an impedance matching circuit can be provided at the input stage of the second rectifier circuit. For example, as in Fig. Figure 14 illustrates that the Rectenna device 100G has a configuration in which an matching circuit 55 is provided at the input stage of the rectifier circuit 20 of the Rectenna device 100C described in the third embodiment.

[0088] Alternatively, a phase shifter can be provided on a transmission line, over which a high-frequency signal emitted by each antenna element is transmitted during the short input power time. For example, as in Fig. Figure 15 shows a phase shifter 56A provided between a switching unit 11A and a rectifier circuit 20, a phase shifter 56B provided between a switching unit 11B and the rectifier circuit 20, a phase shifter 56C provided between a switching unit 11C and the rectifier circuit 20, and a phase shifter 56D provided between a switching unit 11D and the rectifier circuit 20. Each phase shifter operates such that the phase of the output from each antenna element and the phase of the input to the rectifier circuit 20 are essentially the same phase (the phase difference is an integer multiple of approximately 360 degrees). Furthermore, in the case of the Fig. As illustrated in the configuration shown in Figure 15, since the phase between the antenna elements is set, the Rectenna device 100G can receive high power even in a case where the position of a power transmitter changes due to a change in directivity.

[0089] The Rectenna device 100G of the present embodiment can also achieve effects similar to those of the first embodiment. Furthermore, reflection due to impedance mismatch can be prevented, and the Rectenna device 100G can achieve a high conversion efficiency overall. [Eighth embodiment]

[0090] Next, an eighth embodiment is described. It should be noted that in the description of the eighth embodiment, the same or similar configurations in the preceding description are designated by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the aspects (configurations, effects, and the like) described in other embodiments may be applied to the eighth embodiment unless otherwise specified.

[0091] Fig. Figure 16 is a diagram describing a configuration example of a rectenna device (rectenna device 100H) according to the eighth embodiment. In the embodiment described above, the first rectifier circuit (for example, rectifier circuit 12A, rectifier circuit 12B, rectifier circuit 12C, and rectifier circuit 12D) is provided for each antenna element, but the first rectifier circuit can be provided for each group of antenna elements comprising a plurality of antenna elements. For example, a first rectifier circuit can be provided for each group of antenna elements comprising four antenna elements. In the case of the one described in Figure 16, the first rectifier circuit can be provided for each group of antenna elements comprising four antenna elements. Fig. In the Rectenna device 100H shown in Figure 16, for example, an antenna element group 64A is formed by an antenna element 60A, an antenna element 61A, an antenna element 62A, and an antenna element 63A. A rectifier circuit 12A is provided for the antenna element group 64A. Furthermore, an antenna element group 64B is formed by an antenna element 60B, an antenna element 61B, an antenna element 62B, and an antenna element 63B. A rectifier circuit 12B is provided for the antenna element group 64B. Furthermore, an antenna element group 64C is formed by an antenna element 60C, an antenna element 61C, an antenna element 62C, and an antenna element 63C. A rectifier circuit 12C is provided for the antenna element group 64C. Furthermore, an antenna element group 64D is formed by an antenna element 60D, an antenna element 61D, an antenna element 62D and an antenna element 63D.A rectifier circuit 12D is provided for the antenna element group 64D.

[0092] In a case where the Rectenna device 100H operates in high-input mode, a control unit 40 performs switching control so that a high-frequency signal obtained by combining high-frequency signals output by the four antenna elements is fed to a first rectifier circuit corresponding to the four antenna elements. For example, a high-frequency signal RFAA, obtained by combining high-frequency signals output by antenna element group 64A, i.e., the four antenna elements (antenna element 60A, antenna element 61A, antenna element 62A, and antenna element 63A), is fed to a switching unit 11A. The switching unit 11A is switched according to a switching control of the control unit 40, and the high-frequency signal RFAA is fed to the rectifier circuit 12A via the switching unit 11A.The rectifier circuit 12A receives DC power DCAA by rectifying the high frequency signal RFAA from the switching unit 11A.

[0093] Additionally, a high-frequency signal RFBB, obtained by combining high-frequency signals output by antenna element group 64B (i.e., the four antenna elements 60B, 61B, 62B, and 63B), is fed to a switching unit 11B. The switching unit 11B is switched according to a switching control of the control unit 40, and the high-frequency signal RFBB is fed to the rectifier circuit 12B via the switching unit 11B. The rectifier circuit 12B receives DC power DCBB by rectifying the high-frequency signal RFBB supplied by the switching unit 11B.

[0094] Additionally, a high-frequency signal RFCC, obtained by combining high-frequency signals output by the antenna element group 64C, i.e., the four antenna elements (antenna element 60C, antenna element 61C, antenna element 62C, and antenna element 63C), is fed to a switching unit 11C. The switching unit 11C is switched according to a switching control of the control unit 40, and the RFCC signal is fed to the rectifier circuit 12C via the switching unit 11C. The rectifier circuit 12C receives DC power DCCC by rectifying the RFCC signal supplied by the switching unit 11C.

[0095] Additionally, a high-frequency signal RFDD, obtained by combining high-frequency signals output by the antenna element group 64D, i.e., the four antenna elements (antenna element 60D, antenna element 61D, antenna element 62D, and antenna element 63D), is fed to a switching unit 11D. The switching unit 11D is switched according to a switching control of the control unit 40, and the high-frequency signal RFDD is fed to the rectifier circuit 12D via the switching unit 11D. The rectifier circuit 12D receives DC power DCDD by rectifying the high-frequency signal RFDD supplied by the switching unit 11D. Then the control unit 40 controls a switching unit 21, so that DC power, obtained by combining the DC power DCAA, the DC power DCBB, the DC power DCCC and the DC power DCDD, is supplied to a load 30.

[0096] In a case where the Rectenna device 100H operates in low-input-power mode, the control unit 40 performs switching control at each switching unit (switching unit 11A, switching unit 11B, switching unit 11C, and switching unit 11D) so that a high-frequency signal, obtained by combining high-frequency signals output by the 16 antenna elements, is fed to a rectifier circuit 20. According to the switching control, a high-frequency signal RFPP, obtained by combining the high-frequency signals output by the 16 antenna elements, is fed to the rectifier circuit 20. The rectifier circuit 20 receives DC power DCPP by rectifying the high-frequency signal RFPP. The control unit 40 then controls the switching unit 21 so that the DC power DCPP is supplied to the load 30.

[0097] In this way, the rectenna device, according to the present technology, can operate in units of antenna element groups. For example, in the case of millimeter waves, since the size of a physical antenna element is small, the number of antenna elements on the rectenna device side (power receiving side) can be increased. Therefore, it is possible to handle a wider input power range by using the sub-arrangement (antenna element group). For example, with a total of 16 elements, if the antenna element group is configured not only for each element but also for every fourth element, and the outputs of the 16 elements are combined and used during the low input power operating time, a gain improvement in the range of 12 dB is ideally expected.

[0098] In a case where the number of antenna elements and the connection mode of the antenna elements are generalized in the present embodiment, the rectenna device is preferably a rectenna device in which there are certain integer sets N1, N2,... and N m The number of antenna elements Σ i N i 2 is and the connection mode of each N i 2 -Antenna element N i in series and N i parallel.

[0099] With such a configuration, the impedance of the antenna element and the impedance when the antenna element group is formed can be made essentially the same. That is, since the impedances are matched, high efficiency of the rectenna device can be achieved. Furthermore, it is possible to simplify the design of the rectenna device and reduce the time and effort required for its design. [Ninth embodiment]

[0100] Next, a ninth embodiment is described. It should be noted that in the description of the ninth embodiment, the same or similar configurations in the preceding description are designated by the same reference numerals, and redundant descriptions are omitted where appropriate. Furthermore, the aspects (configurations, effects, and the like) described in other embodiments may be applied to the ninth embodiment unless otherwise specified.

[0101] Fig. 17A and Fig. Figure 17B contains diagrams describing a configuration example of a rectenna device (rectenna device 100J) according to the ninth embodiment. For example, the rectenna device 100J has a configuration similar to that of the rectenna device 100A described above. The rectenna device 100J further comprises a substrate (mainboard) 71 on which the components of the rectenna device 100J are mounted. Components of the rectenna device 100J are removable from the substrate 71. A block removable from the rectenna device 100J can be a block comprising a single component or a block comprising a plurality of components.

[0102] As an example, a block is formed by an antenna element and components that have a high-frequency signal output and a DC power output. In particular, as shown in Fig. Figure 17A shows an antenna element 10A, a switching unit 11A, and a rectifier circuit 12A forming a block 72A. The block 72A is removable from the substrate 71. As shown in Fig. As shown in Figure 17B, when block 72A is attached to substrate 71, the wiring of block 72A and the wiring of substrate 71 are suitably connected. Furthermore, an antenna element 10B, a switching unit 11B, and a rectifier circuit 12B form block 72B. Block 72B is detachable from substrate 71. As shown in Fig. As shown in Figure 17B, when block 72B is attached to substrate 71, a wiring of block 72B and a wiring of substrate 71 are suitably connected.

[0103] A block can comprise a component of the Rectenna device 100J, for example, as in Fig. As shown in Figure 18A, block 72A includes antenna element 10A, and block 72B can include antenna element 10B. It should be noted that once each block is attached to substrate 71, the operation is similar to that of the Rectenna device 100A.

[0104] According to the present embodiment, the Rectenna device 100J can be manufactured to a suitable size, even considering the limitations of area, weight, and the like required by the device to which the Rectenna device 100J is applied. Furthermore, the substrate 71 can be cut as required. Furthermore, as described in Fig. Figure 18A illustrates a case where a block contains an antenna element; the antenna elements of the respective blocks are not the same antenna element and can be of different types. Consequently, it is possible to adapt the rectenna device so that it is a rectenna device capable of handling different polarizations, angles of incidence of electromagnetic waves, and the like. [Application example]

[0105] Specific application examples of the rectenna device according to the present technology are described. (Example of an electronic device)

[0106] Fig. 19A to Fig. Section 19J provides specific examples of an electronic device to which the rectenna device according to the present technology is applicable. As in Fig. As shown in Figure 19A, the rectenna device according to the present technology can, for example, be applied to a smartphone. Furthermore, as shown in Fig. As shown in Figure 19B, the rectenna device according to the present technology is applicable, for example, to wireless earphones. Furthermore, as shown in Fig. As shown in Figure 19C, the Rectenna device according to the present technology can be applied, for example, to a glasses-like device for virtual reality (VR). Furthermore, as shown in Fig. As shown in Figure 19D, the rectenna device according to the present technology can be applied, for example, to a smartwatch. Furthermore, as shown in Fig. As shown in Figure 19E, the rectenna device according to the present technology can be applied, for example, to the control of a gaming device. Furthermore, as shown in Fig. 19F shows that the rectenna device according to the present technology can be applied, for example, to a television device.

[0107] Furthermore, according to the present technology, the rectenna device is also applicable to a moving body.

[0108] As in Fig. As shown in Figure 19G, the Rectenna device according to the present technology is applicable, for example, to a ship. Furthermore, as shown in Fig. As shown in Figure 19H, the rectenna device according to the present technology is applicable, for example, to an aircraft such as a drone. Furthermore, as shown in Fig. As shown in Figure 19I, the rectenna device according to the present technology is applicable, for example, to an autonomously moving robot (in the illustrated example, a dog-shaped robot). As shown in Fig. As shown in Figure 19J, the Rectenna device according to the present technology is applicable, for example, to an autonomous cleaning robot. Furthermore, in addition to the examples shown, the Rectenna device according to the present technology can be mounted on a sensing device with a sensor (for example, a vital sign sensor that measures biometric information (heart rate, body temperature, blood pressure, and the like) of a person, or an environmental sensor that measures environmental information), an external device with a USB output, or various portable devices. (Specific system configuration example)

[0109] A specific system configuration example to which the Rectenna device is applicable according to the present technology, and an example of processing carried out in the system are described. Fig. 20 and Fig. Figure 21 represents a mode of a power transmission and reception system (power transmission and reception system 80) according to the present technology. The power transmission and reception system 80 comprises, for example, a power transmitter 81 and a smartphone 82. The rectenna device according to the present technology, such as the rectenna device 100A described in the first embodiment, is integrated into the smartphone 82. Of course, a rectenna device other than the rectenna device 100A, such as the rectenna device 100B, can be applied to the smartphone 82. It should be noted that in a case where any rectenna device, such as the rectenna device 100A, the rectenna device 100B, ... the rectenna device 100J described above, can be used, the rectenna device may be collectively referred to as a rectenna device 100.

[0110] The power transmitter 81 is a power transmission router or similar device that emits electromagnetic waves. The Rectenna device 100A integrated into the smartphone 82 receives the electromagnetic waves emitted by the power transmitter 81. As in Fig. As shown in Figure 20, in a case where the distance between the power transmitter 81 and the smartphone 82 is long (for example, the distance between the power transmitter 81 and the smartphone 82 is x meters), the electromagnetic waves received by the Rectenna device 100A are small. Accordingly, the Rectenna device 100A operates in low-input-power mode. On the other hand, as shown in Fig. Figure 21 shows that in a case where the distance between the power transmitter 81 and the smartphone 82 is short (for example, the distance between the power transmitter 81 and the smartphone 82 is y meters (x > y)), the electromagnetic waves received by the Rectenna device 100A are large. Accordingly, the Rectenna device 100A operates in the high-input-power mode.

[0111] Fig. Figure 22 is a block diagram illustrating a configuration example of an electronic device (electronic device 90) to which the Rectenna device 100 is applied. In addition to the Rectenna device 100, the electronic device 90 includes a voltage sensing unit 85, a DC-DC converter 86, a power supply circuit 87, and a load 88. The voltage sensing unit 85 is connected to the output stage of the Rectenna device 100. The DC-DC converter 86 is connected to the output stage of the voltage sensing unit 85. The power supply circuit 87 is connected to the output stage of the DC-DC converter 86. The load 88 is connected to the output stage of the power supply circuit 87.

[0112] The voltage sensing unit 85 detects a voltage output by at least one first rectifier circuit in the rectenna device 100. The voltage detected by the voltage sensing unit 85 is fed back to the rectenna device 100. Based on the feedback voltage, the rectenna device 100 switches between the low-input-power operating mode and the high-input-power operating mode. That is, the voltage sensing unit 85 corresponds to an example of the output parameter sensing unit 41 described above. It should be noted that the embodiment described above refers to a configuration example in which the rectenna device 100 includes the output parameter sensing unit 41.However, as in the present example, a component corresponding to the output parameter acquisition unit 41 can be provided at the output stage of the rectenna device 100. That is, the rectenna device 100 can omit the output parameter acquisition unit 41.

[0113] The DC-DC converter 86 is a step-down-boost converter that amplifies or reduces the output of the rectenna device 100. When the rectenna device 100 operates in low-input mode, that is, when a second output is provided by a second rectifier circuit of the rectenna device 100, the DC-DC converter 86 amplifies this second output. Even with low input power, the rectenna device 100 can achieve high conversion efficiency according to the technology used. However, the total DC power output of the rectenna device 100 may be lower than that provided during periods of high input power. Therefore, the load 88 can be operated stably by amplifying the second output of the rectenna device 100 using the DC-DC converter 86.

[0114] On the other hand, when the Rectenna device 100 operates in high-input mode, that is, when a first output obtained by combining the outputs of multiple first rectifier circuits is output by the Rectenna device 100, the DC-DC converter 86 reduces the first output. When the Rectenna device 100 operates in high-input mode, the first output from the Rectenna device 100 may be excessive, depending on the load 88. Therefore, the load 88 can be operated stably by reducing the first output from the Rectenna device 100 using the DC-DC converter 86. It should be noted that the Rectenna device 100 can include the DC-DC converter 86, as in the present example. In this case, the DC-DC converter 86 is provided, for example, at the output stage of the switching unit 21.

[0115] The power supply circuit 87 serves to stabilize an output voltage or output current. Any known power supply circuit can be used as the power supply circuit 87. An output of the power supply circuit 87 is fed to the load 88. The load 88 is a load corresponding to the electronic device to which the rectenna device 100 is applied.

[0116] Fig. Figure 23 is a block diagram describing an example of a power transmission and reception system comprising a power transmitter and an electronic device to which the Rectenna device 100 is applied. The in Fig. The power transmission and reception system shown in Figure 23 comprises a 200A power transmitter and a 300A electronic device.

[0117] The power transmitter 200A according to the present example comprises a power transmitter IC 201 which comprehensively controls the power transmitter 200A, a power transmission antenna 202 which emits electromagnetic waves according to the control of the power transmitter IC 201, and a communication module 203 which communicates with an external device.

[0118] The electronic device 300A according to the present example is, for instance, a sensing device. In addition to the rectenna device 100, voltage sensing unit 85, DC-DC converter 86, and power supply circuit 87 described above, the electronic device 300A includes a sensor 301 and a communication module 302 (an example of a communication unit) that communicates with an external device. The sensor 301 and the communication module 302 operate using power supplied by the power supply circuit 87. This example is one in which the load 88 described above corresponds to the sensor 301.

[0119] Data acquired by sensor 301 is transmitted by communication module 302 to power transmitter 200A. Examples of acquired data include biometric information, environmental information, and the like. In addition to acquired data, power output information from the Rectenna device 100 may also be included in the data transmitted to power transmitter 200A.

[0120] The acquisition data transmitted by the electronic device 300A is received by the communication module 203 of the power transmitter 200A. The power transmitter 200A can transmit the received acquisition data to another device using the communication module 203.

[0121] Examples of other devices include a cloud server and an electronic device owned by the same user as the user of electronic device 300A.

[0122] Fig. Figure 24 is a block diagram for describing another power transmission and reception system. The one in Fig. The power transmission and reception system shown in Figure 24 comprises a power transmitter 200B and an electronic device 300B. The present example is one in which the electronic device 300B includes the communication module 302, which communicates with the power transmitter 200B. The operating mode is switched between high-input-power and low-input-power modes by the communication module 302 according to the communication content. That is, in this example, control is performed in which the number of antenna elements connected to a first rectifier circuit and a second rectifier circuit is changed by the communication module 302 according to the communication content.

[0123] The power transmitter 200B according to the present example has the same configuration as, for example, the power transmitter 200A. The electronic device 300B according to the present example has a configuration in which, for example, the voltage sensing unit 85 is not provided and a power-receiving IC 305 is added to the configuration of the electronic device 300A.

[0124] In the present example, communication takes place between the power transmitter 200B and the electronic device 300B. For example, the power transmitter 200B and the electronic device 300B transmit and receive mutual position information and battery charge levels (not shown). The battery is charged, for example, by the output of the power supply circuit 87, and the power output by the battery is supplied to the load 88.

[0125] For example, position information is transmitted and received between the power transmitter 200B and the electronic device 300B. As a result of this communication, the power transmitter 200B, when located close to the electronic device 300B, reduces the radiated output of the electromagnetic waves so that the rectenna device 100 and the load 88 are not affected by excessive power. Additionally, the control unit 40 in the rectenna device 100 of the electronic device 300B performs switching control at each switching unit to operate in low-input-power mode. As described in the first embodiment and similar descriptions, the number of antenna elements connected to the first rectifier circuit and the second rectifier circuit is changed according to this switching control.

[0126] The electronic device 300B then notifies the power transmitter 200B, after confirming that there is no safety issue or similar problem related to the power output. Additionally, according to the control by the power receiver IC 305, switching control is performed at each switching unit by the control unit 40, so that the rectifier device 100 operates in high-input-power mode. As described in the first embodiment and similar versions, the number of antenna elements connected to the first and second rectifier circuits is changed according to this switching control. The power transmitter 200B, having received the notification, then increases its electromagnetic wave output and emits the electromagnetic waves.As a result, it is possible to safely transmit the maximum power from the 200B power transmitter to the 300B electronic device.

[0127] Additionally, in electronic device 300B, for example, it is assumed that the power receiver IC 305 determines that there is no problem operating load 88, even if the battery charging rate is slow. In this case, the power receiver IC 305 controls the communication module 302 to notify the power transmitter 200B that the input power to the rectenna device 100 does not need to be high. Then, in the rectenna device 100, switching control is performed on each switching unit to operate in low-input-power mode. Furthermore, the power transmitter 200B, having received the notification, reduces the radiated electromagnetic wave output. As a result, the loss on the power transmission side can be reduced, and efficient power transmission can be achieved.

[0128] Fig. 25 is a flowchart that depicts the sequence of a specific processing example, which is described in Fig. The power transmission and reception system shown in section 24 is carried out.

[0129] In step ST11, the electronic device 300B notifies the power transmitter 200B via communication that the battery charge of the electronic device 300B is insufficient. The processing then proceeds to each of the following steps: ST12 and ST13.

[0130] In step ST12, the power transmitter IC 201 performs a control operation to increase the radiated output of the electromagnetic waves emitted by the power transmitter 200B. This control operation increases the radiated output of the electromagnetic waves emitted by the power transmission antenna 202.

[0131] In step ST13, the power receiver IC 305 instructs the Rectenna device 100 to perform a switching control to activate each switching unit so that it operates in high-input-power mode. In response to this instruction, the Rectenna device 100 performs the switching control and operates in high-input-power mode. The power receiver IC 305 then monitors whether the battery is sufficiently charged. Following steps ST12 and ST13, processing proceeds to step ST14.

[0132] In step ST14, the electronic device 300B notifies the power transmitter 200B via communication if the battery of the electronic device 300B is sufficiently charged. The processing then proceeds to each of the following steps: ST15 and ST16.

[0133] In step ST15, the power transmitter IC 201 performs a control operation to reduce the radiated output of the electromagnetic waves emitted by the power transmitter 200B. This control operation reduces the radiated output of the electromagnetic waves emitted by the power transmission antenna 202.

[0134] Additionally, in step ST16, the power-receiving IC 305 instructs the Rectenna device 100 to perform switching control to activate each switching unit in order to operate in low-input-power mode. In response to this instruction, the Rectenna device 100 performs switching control and operates in low-input-power mode. By performing the processing described above, the electromagnetic wave output from the power transmission side is adjusted according to the power required by the electronic device 300B, which is the power-receiving side, thus reducing electromagnetic wave loss and enabling efficient power transmission.

[0135] In addition, the following advantages can be obtained by transferring the detected output (e.g., DC power) of the rectenna device from the electronic device on the power receiving side to the power transmitter on the transmission side.

[0136] For example, if the distance between the electronic device on the power receiver side and the power transmitter is known, the power transmitter can estimate the environment by feeding back the output detected on the electronic device side. For instance, if the output fed back with respect to the distance is small, the power transmitter can determine that the environment is one where electromagnetic waves are easily shielded or reflected. In this case, the power transmitter can increase the radiated output of the electromagnetic waves or change the directionality.

[0137] Furthermore, in a case where the influence of the environment is small, the distance between the electronic device and the power transmitter can be estimated based on the output detected on the side of the electronic device. [Modification]

[0138] Although the embodiments of the present technology have been specifically described above, the content of the present technology is not limited to the embodiments described above and various modifications based on the technical concept of the present technology are possible.

[0139] The components that make up the rectenna device can be arranged in a three-dimensional (3D) manner. For example, as in Fig. Figure 26 shows an antenna element, a switching unit connected to the antenna element, and a first rectifier circuit (rectifier circuit 12A, rectifier circuit 12B, rectifier circuit 12C, and rectifier circuit 12D in the illustrated example) arranged on at least two surfaces of a cubic substrate 95. In such a configuration, it is also assumed that the input power to each antenna element differs depending on the direction of incidence of the electromagnetic waves. In this case, as described in the embodiment, switching control is performed according to the input power to the antenna element, and optimal efficiency can be achieved.

[0140] Furthermore, as described in the eighth embodiment, in a case where the first rectifier circuit is provided for each antenna element group, the number of antenna elements connected to the second rectifier circuit (to which a signal is supplied) can be changed according to a plurality of threshold values ​​set for the output parameters.

[0141] Fig. 27 is a diagram illustrating a configuration example of a rectenna device according to the present modification. The in Fig. Figure 27 shows a rectenna device with an antenna element group circuit comprising an antenna element group and its peripheral circuits. For example, the one shown in Fig. Figure 27 shows a rectenna device comprising four antenna element groups (antenna element group 96A, antenna element group 96B, antenna element group 96C, and antenna element group 96D). In the present modification, the four antenna element groups have the same configuration. However, each antenna element group may have a different configuration. In the following description, where it is not necessary to distinguish between the individual antenna element groups, they may be referred to collectively as one antenna element group 96.

[0142] The antenna element assembly 96 has a terminal TA and a terminal TB. RF signals output by one or a plurality of antenna elements included in the antenna element assembly 96 are output from terminal TA and terminal TB. The RF signals output by the antenna element assembly 96 are combined and fed to a rectifier circuit 20. The antenna element assembly 96 also includes a terminal TC and a terminal TD. DC power DC obtained by rectifying the RF signals output by the one or a plurality of antenna elements included in the antenna element assembly 96 is output from terminal TC and terminal TD.

[0143] Fig. Figure 28 is a diagram illustrating a configuration example of the antenna element group circuit 96. The antenna element group circuit 96 comprises an antenna element 97A, an antenna element 97B, an antenna element 97C, and an antenna element 97D. In the present modification, the four antenna elements form an antenna element group.

[0144] A switching unit 98A is connected to the output stage of the antenna element 97A. A rectifier circuit 99A and terminals TA and TB are connected to the output stage of the switching unit 98A. Terminals TC and TD are connected to the output stage of the rectifier circuit 99A. The switching unit 98A switches the supply destination of the RF signal output by the antenna element 97A to terminals TA and TB or to the rectifier circuit 99A. Additionally, the switching unit 98A is configured so that the switch contained within it can also be connected to ground. In a case where the switching unit 98A is connected to ground, the RF signal output by the antenna element 97A can be prevented from being output to the subsequent stage of the switching unit 98A.

[0145] Furthermore, a switching unit 98B is connected to the output stage of the antenna element 97B. A rectifier circuit 99B, terminals TA and TB, are connected to the output stage of the switching unit 98B. Terminals TC and TD are connected to the output stage of the rectifier circuit 99B. The switching unit 98B switches the supply destination of the RF signal output by the antenna element 97B to terminals TA and TB or to the rectifier circuit 99B. Additionally, the switching unit 98B is configured so that the switch contained within it can also be connected to ground, for example. In a case where the switching unit 98B is connected to ground, the RF signal output by the antenna element 97B can be prevented from being output to the subsequent stage of the switching unit 98B.

[0146] Furthermore, a switching unit 98C is connected to the output stage of the antenna element 97C. A rectifier circuit 99C, terminal TA, and terminal TC are connected to the output stage of the switching unit 98C. Terminal TC and terminal TD are connected to the output stage of the rectifier circuit 99C. The switching unit 98C switches the supply destination of the RF signal output by the antenna element 97C to terminal TA and terminal TB or to the rectifier circuit 99C. Additionally, the switching unit 98C is configured so that the switch contained within the switching unit 98C can also be connected to ground. In a case where the switching unit 98C is connected to ground, the RF signal output by the antenna element 97C can be prevented from being output to the subsequent stage of the switching unit 98C.

[0147] Furthermore, a switching unit 98D is connected to the output stage of the antenna element 97D. A rectifier circuit 99D, terminals TA and TB, are connected to the output stage of the switching unit 98D. Terminals TC and TD are also connected to the output stage of the rectifier circuit 99D. The switching unit 98D switches the supply destination of the RF signal output by the antenna element 97D to terminals TA and TB or to the rectifier circuit 99D. Additionally, the switching unit 98D is configured so that the switch contained within it can also be connected to ground. In a case where the switching unit 98D is connected to ground, the RF signal output by the antenna element 97D can be prevented from being output to the subsequent stage of the switching unit 98D.It should be noted that switching control on each of the switching unit 98A, the switching unit 98B, the switching unit 98C and the switching unit 98D is carried out, for example, by a control unit 40.

[0148] An operating example of the rectenna device according to the present modification is described. In a case where the DC power output from one antenna element is a large input power greater than a threshold Ta, since it is not necessary to use the outputs of the four antenna elements, the antenna element group circuit 96, for example, selects one antenna element and outputs the output of the selected antenna element to the corresponding first rectifier circuit. The antenna element group circuit 96, for example, performs a switching control at the switching unit 98A so that the RF signal from the antenna element 97A is fed to the rectifier circuit 99A.Furthermore, the antenna element group circuit 96 performs switching control at the switching unit 98B, switching unit 98C, and switching unit 98D, so that the RF signal from each of the antenna elements 97B, 97C, and 97D is not output to the subsequent stage. According to this control, DC power obtained by rectifying the RF signal from antenna element 97A by the rectifier circuit 99A is output from terminal TC and terminal TD. The DC power output from each antenna element group circuit 96 is combined, and the combined DC power is supplied to a load 30 via a switching unit 21.

[0149] Additionally, in a case where the DC power output from an antenna element is equal to or greater than a threshold value Tb (where Ta > Tb) (a case of average input power), the antenna element group 96 selects an antenna element and outputs the output of the selected antenna element to the second rectifier circuit. For example, the antenna element group 96 performs switching control at switching unit 98A so that the RF signal from antenna element 97A is fed to terminal TA and terminal TB. Furthermore, the antenna element group 96 performs switching control at switching units 98B, 98C, and 98D so that RF signals are not output from antenna elements 97B, 97C, and 97D.According to this control, the RF signals output by the respective antenna element group circuits 96 are combined and fed to the rectifier circuit 20. That is, the RF signals of the four antenna elements are combined and fed to the rectifier circuit 20. In this case, the number of antenna elements connected to the rectifier circuit 20 is 4. The DC power obtained by rectifying the combined RF signal through the rectifier circuit 20 is supplied to the load 30 via the switching unit 21.

[0150] Furthermore, during the short input power period, when the DC power output from the antenna element is less than the threshold Tb, the antenna element group 96 selects all antenna elements and outputs the output of the selected antenna elements to the corresponding secondary rectifier circuits. For example, the antenna element group 96 performs switching control on each of the switching unit 98A, switching unit 98B, switching unit 98C, and switching unit 98D, such that the RF signal output by antenna element 97A, the RF signal output by antenna element 97B, the RF signal output by antenna element 97C, and the RF signal output by antenna element 97D are fed to terminal TA and terminal TB, respectively. According to such a control, an RF signal obtained by combining the RF signals from the four antenna elements is output from the TA terminal and the TB terminal.The RF signals output by the four antenna element groups 96 are then combined and fed to the rectifier circuit 20. That is, the RF signals output by the 16 antenna elements are combined and fed to the rectifier circuit 20. In this case, the number of antenna elements connected to the rectifier circuit 20 is 16. The DC power obtained by rectifying the combined RF signal through the rectifier circuit 20 is supplied to the load 30 via the switching unit 21. It should be noted that the number of threshold values ​​set for the output parameters can be three or more instead of two. According to the present modification, effects similar to those of the eighth embodiment can also be obtained.

[0151] Furthermore, as in Fig. Figure 29 shows a switching unit 110A being connected to a terminal TA and a terminal TB of an antenna element group circuit 96A, a switching unit 110B being connected to the terminal TA and the terminal TB of an antenna element group circuit 96B, a switching unit 110C being connected to the terminal TA and the terminal TB of an antenna element group circuit 96C, and a switching unit 110D being connected to the terminal TA and the terminal TB of an antenna element group circuit 96D.

[0152] A 120A rectifier circuit and a 20 rectifier circuit are connected to the output stage of the 110A switching unit. The 110A switching unit directs the power supply of an RF signal output from terminals TA and TB of the 96A antenna element group to either the 120A rectifier circuit or the 20 rectifier circuit. A 120B rectifier circuit and the 20 rectifier circuit are connected to the output stage of the 110B switching unit. The 110B switching unit directs the power supply of the RF signal output from terminals TA and TB of the 96B antenna element group to either the 120B rectifier circuit or the 20 rectifier circuit. A 120C rectifier circuit and the 20 rectifier circuit are connected to the output stage of the 110C switching unit.The switching unit 110C switches the power supply destination of the RF signal output from terminals TA and TB of the antenna element group circuit 96C to the rectifier circuit 120C or the rectifier circuit 20. A rectifier circuit 120D and the rectifier circuit 20 are connected to the output stage of the switching unit 110D. The switching unit 110D switches the power supply destination of the RF signal output from terminals TA and TB of the antenna element group circuit 96D to the rectifier circuit 120D or the rectifier circuit 20. Outputs of the rectifier circuit 120A, the rectifier circuit 120B, the rectifier circuit 120C, and the rectifier circuit 120D can, for example, be combined and supplied to a load 30 via a switching unit 21.

[0153] According to the in Fig.In the Rectenna device shown in Figure 29, a rectifier circuit (rectifier circuit 120A, rectifier circuit 120B, rectifier circuit 120C, and rectifier circuit 120D in this example) can be provided for the RF signals output by the four antenna elements contained in the antenna element group circuits and combined. The DC power output by the four rectifier circuits—rectifier circuit 120A, rectifier circuit 120B, rectifier circuit 120C, and rectifier circuit 120D—can be combined and supplied to the switching unit 21.Furthermore, according to the switching control for the switching unit 110A or the like, the DC power output by any of the four rectifier circuits can be supplied to the switching unit 21, or the DC power output by some (for example, the rectifier circuit 120A and the rectifier circuit 120B) of the four rectifier circuits can be supplied to the switching unit 21 instead of all of the four rectifier circuits.

[0154] In the embodiment described above, an example was described in which the switching control for each switching unit is performed automatically, but the switches can be operated manually. Consequently, since the Rectenna device can be actuated by a user-desired actuation, a Rectenna device (electronic device with the Rectenna device) can be provided that can handle a case where there is a need for adaptation.

[0155] In a case where the electronic device is a robot that can move autonomously, in a case where the output parameter (for example, the voltage) detected by the output parameter detection unit 41 is small, the electronic device can be brought close to the power transmitter side to increase the input power into the antenna element of the rectenna device.

[0156] A large number of electronic devices can be connected to the Rectenna device, and these devices can communicate with each other to control the switching unit, thereby switching the wiring. With such a configuration, it is possible to achieve high conversion efficiency of the electromagnetic waves from the power transmitter to a large number of electronic devices on the power receiver side. For example, one electronic device in a group of electronic devices (equipment) on the power receiver side can act as a host for another electronic device. Then, for example, the output parameter is only detected by the host electronic device, and switching control is performed based on this parameter.The electronic host device transmits control information to another electronic device via communication, enabling switching based on the output parameter. The other electronic device then performs switching at each switching unit based on the control information transmitted by the electronic host device. As a result, the same switching control can be performed in a variety of electronic devices on the power receiver side. Since the output sensing function only needs to be included in the electronic host device, the configuration of the electronic device can be simple and cost-effective while maintaining high conversion efficiency, and the electronic device can be independent of the specifications on the power transmitter side.

[0157] Furthermore, a multitude of technologies relating to the present technology can be implemented independently as a single entity, provided there is no contradiction. It is understood that any multitude of the present technologies can be implemented in combination. For example, some or all of the present technologies described in any embodiment can be implemented in combination with some or all of the present technologies described in other embodiments. Furthermore, some or all of the present technologies described above can be implemented together with another technology not described above.

[0158] The configurations, methods, processes, shapes, materials, numerical values, and the like described in the embodiments and modifications are merely examples, and configurations, methods, processes, shapes, materials, numerical values, and the like that differ from those described above may be used as required. Furthermore, the materials illustrated in the embodiments and modifications may be used alone or in combination with two or more, unless otherwise specified. Additionally, the components described in the embodiments and modifications may be combined as appropriate.

[0159] It should be noted that the effects described in this description are merely examples and are not limiting, and other effects may be provided.

[0160] The present technology can also assume the following configurations. (1)

[0161] Rectenna device, which includes the following: two or more antenna elements; a first rectifier circuit provided for each of the antenna elements, which rectifies one output of the antenna element; and a second rectifier circuit that can combine and input the outputs of the two or more antenna elements and rectifies the combined output, wherein A control is performed to change the number of antenna elements connected to each of the first rectifier circuit and the second rectifier circuit. (2)

[0162] Rectenna device according to (1), wherein A control operation is performed to change the number of antenna elements according to an output parameter that corresponds to an input power into the antenna elements. (3)

[0163] Rectenna device according to (2), wherein The output parameter includes at least one of the parameters relating to an output voltage of the rectifier circuit, an output current of the rectifier circuit, an output power of the rectifier circuit, an impedance of the rectifier circuit, and a load connected to the rectenna device. (4)

[0164] Rectenna device according to (2), wherein In a case where the output parameter is a first output parameter corresponding to the fact that an input power to the antenna element is less than a predetermined value, control is carried out to reduce the number of antenna elements connected to the first rectifier circuit and to increase the number of antenna elements connected to the second rectifier circuit, and In a case where the output parameter is a second output parameter corresponding to the fact that an input power to the antenna element is greater than the predetermined value, control is carried out to increase the number of antenna elements connected to the first rectifier circuit and to reduce the number of antenna elements connected to the second rectifier circuit. (5)

[0165] Rectenna device according to (4), wherein a first output, obtained by combining outputs from two or more of the first rectifier circuits, and a second output, switched and output by the second rectifier circuit. (6)

[0166] Rectenna device according to (5), wherein The connection type of the antenna elements can be changed. (7)

[0167] Rectenna device according to (5) or (6), further comprising: a converter that amplifies the second output. (8)

[0168] Rectenna device according to one of (5) to (7), which further comprises: a converter that reduces the first output. (9)

[0169] Rectenna device according to one of (1) to (8), wherein one of the first rectifier circuits and the second rectifier circuit have a common configuration. (10)

[0170] Rectenna device according to one of (1) to (9), wherein An matching circuit is provided at an input stage of the second rectifier circuit. (11)

[0171] Rectenna device according to one of (1) to (10), wherein The first rectifier circuit is provided for each antenna element group, which comprises a multitude of antenna elements. (12)

[0172] Rectenna device according to one of (2) to (8), wherein the first rectifier circuit is provided for each antenna element group, which comprises a multitude of antenna elements, and The number of antenna elements connected to the second rectifier circuit is changed according to a variety of thresholds set for the output parameter. (13)

[0173] Rectenna device according to one of (1) to (12), wherein The phase difference between an output of the antenna element and an input to the second rectifier circuit is an integer multiple of approximately 360 degrees. (14)

[0174] Rectenna device according to (13), wherein a transmission line length between the antenna element and the second rectifier circuit is set such that a phase difference between an output of the antenna element and an input to the second rectifier circuit is an integer multiple of approximately 360 degrees. (15)

[0175] Rectenna device according to (13), wherein A phase shifter is provided between the antenna element and the second rectifier circuit such that a phase difference between an output of the antenna element and an input to the second rectifier circuit is an integer multiple of approximately 360 degrees. (16)

[0176] Rectenna device according to (1), further comprising: a communication unit that communicates with a power transmitter, whereby A control is carried out to change the number of antenna elements connected to the first rectifier circuit and the second rectifier circuit according to a communication content by the communication unit. (17)

[0177] Rectenna device according to one of (1) to (16), which further comprises: a substrate on which the Rectenna device is mounted. (18)

[0178] Rectenna device according to (17), wherein a block comprising at least the antenna element, the first rectifier circuit provided for each of the antenna elements, and a switching unit that switches between an output of the antenna element and an output of the first rectifier circuit, removable from the substrate. (19)

[0179] Rectenna device according to (17), wherein a block containing the antenna element, which is detachably attached to the substrate. (20)

[0180] Electronic device comprising: the rectenna device according to any one of claims (1) to (19), and a load connected to the rectenna device. REFERENCE MARK LIST 100A to 100J Rectenna device 10A, 10B, 10C, 10D antenna element 11A, 11B, 11C, 11D Switching unit 12A, 12B, 12C, 12D rectifier circuit (first rectifier circuit) 20 Rectifier circuit (second rectifier circuit) 21 Switching unit 30 Last 40 Control unit 41 Output parameter acquisition unit 55 Adaptation circuit 56A, 56B, 56C, 56D Phase shifter 64A, 64B, 64C, 64D antenna element group 72A, 72B Block 86 DC-DC converters 300A, 300B Electronic Device 302 Communication module QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2012-139051

[0003]

Claims

[1] Rectenna device, which features: two or more antenna elements; a first rectifier circuit provided for each of the antenna elements, which rectifies one output of the antenna element; and a second rectifier circuit that can combine and input the outputs of the two or more antenna elements and rectifies the combined output, wherein A control is performed to change the number of antenna elements connected to each of the first rectifier circuit and the second rectifier circuit. [2] Rectenna device according to claim 1, wherein a control is carried out to change the number of antenna elements according to an output parameter corresponding to an input power to the antenna elements. [3] Rectenna device according to claim 2, wherein the output parameter comprises at least one of parameters relating to an output voltage of the rectifier circuit, an output current of the rectifier circuit, an output power of the rectifier circuit, an impedance of the rectifier circuit and a load connected to the rectenna device. [4] Rectenna device according to claim 2, wherein in a case where the output parameter is a first output parameter corresponding to the fact that an input power to the antenna element is less than a predetermined value, control is performed to reduce the number of antenna elements connected to the first rectifier circuit and to increase the number of antenna elements connected to the second rectifier circuit, and in a case where the output parameter is a second output parameter corresponding to the fact that an input power to the antenna element is greater than the predetermined value, control is performed to increase the number of antenna elements connected to the first rectifier circuit and to reduce the number of antenna elements connected to the second rectifier circuit. [5] Rectenna device according to claim 4, wherein a first output obtained by combining outputs from two or more of the first rectifier circuits and a second output are switched and output from the second rectifier circuit. [6] Rectenna device according to claim 5, wherein a connection form of the antenna elements is modifiable. [7] Rectenna device according to claim 5, further comprising: a converter that amplifies the second output. [8] Rectenna device according to claim 5, further comprising: a converter that reduces the first output. [9] Rectenna device according to claim 1, wherein one of the first rectifier circuits and the second rectifier circuit have a common configuration. [10] Rectenna device according to claim 1, wherein an matching circuit is provided at an input stage of the second rectifier circuit. [11] Rectenna device according to claim 1, wherein the first rectifier circuit is provided for each antenna element group comprising a plurality of antenna elements. [12] Rectenna device according to claim 2, wherein the first rectifier circuit is provided for each antenna element group, which comprises a multitude of antenna elements, and The number of antenna elements connected to the second rectifier circuit is changed according to a variety of thresholds set for the output parameter. [13] Rectenna device according to claim 1, wherein each of the antenna elements is provided with a switching unit that switches between a connection to the first rectifier circuit and a connection to the second rectifier circuit. [14] Rectenna device according to claim 1, wherein a phase difference between an output of the antenna element and an input to the second rectifier circuit is an integer multiple of approximately 360 degrees. [15] Rectenna device according to claim 13, wherein a transmission line length between the antenna element and the second rectifier circuit is set such that a phase difference between an output of the antenna element and an input to the second rectifier circuit is an integer multiple of approximately 360 degrees. [16] Rectenna device according to claim 1, further comprising: a communication unit that communicates with a power transmitter, whereby A control is carried out to change the number of antenna elements connected to the first rectifier circuit and the second rectifier circuit according to a communication content by the communication unit. [17] Rectenna device according to claim 1, further comprising: a substrate on which the Rectenna device is mounted. [18] Rectenna device according to claim 17, wherein a block comprising at least the antenna element, the first rectifier circuit provided for each of the antenna elements, and a switching unit that switches between an output of the antenna element and an output of the first rectifier circuit, is removable from the substrate. [19] Rectenna device according to claim 17, wherein a block comprising the antenna element is detachably attached to the substrate. [20] Electronic device comprising: the rectenna device according to claim 1, and a load connected to the rectenna device.

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