JPH037034A - Microwave power receiver - Google Patents

Abstract

PURPOSE:To receive a microwave signal of circular polarization and efficiently output a DC power by linearly arranging two microstrip lines via diodes and connecting the lines in series or in parallel with each other. CONSTITUTION:Two microstrip lines 51 are linearly arranged with a space therebetween and diodes 53 are arranged as sandwiched between both ends of the spaces to form a microstrip resonator. The component of the resonant microstrip resonator of circular polarization in the direction of arrangement is rectified by the diodes 53 to be converted to a DC power. When output voltages are connected with each other in series or in parallel, the DC power can be efficiently obtained with a circularly polarized wave as orthogonal two- directional components. Thus, the power of microwave signals can efficiently be D/C-converted and outputted by a simple structure.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides microwave power for receiving a microwave signal transmitted by circularly polarized waves and generating DC power from the power of this microwave No. 13. The present invention relates to a receiving device.

(Prior Art) In recent years, response devices have been carried by people or attached to moving objects.
The answering device stores appropriate information on the person possessing it or the attached moving object, and transmits an interrogation signal by microwave from the fixed interrogation device to this answering device,
The response device that received and demodulated this interrogation signal sends an appropriate response signal by microwave to the quality control device δ. Systems for identifying objects have been proposed. The personal information stored in this response device allows the response device to function as an ID card or driver's license. In addition, in manufacturing factories that perform high-mix, low-volume production, this response device that stores specification data is attached to semi-finished products on the production line, and the inquiry device installed at each process queries the response device for specifications. If work is performed according to this specification, the response device can function as an electronic specification instruction sheet.

Here, when the response device functions as the above-mentioned ID card, driver's license, specification sheet, etc., it is inconvenient to supply drive power from a commercial AC power source for mobile or mobile devices, and the built-in battery If driving power is supplied from the transponder, sufficient satisfaction cannot be obtained in terms of the size and weight of the response device and its lifespan.

Therefore, a technique that utilizes the power of a microwave signal transmitted from an external interrogation device to a response device as a driving power source is disclosed in Japanese Patent Laid-Open Nos. 56-140486 and 63-54023, etc. is shown. An overview of the conventional communication system shown above will be explained with reference to the block circuit diagram shown in FIG.

In FIG. 5, the interrogation device 1 includes a first oscillation circuit 2 that excavates a first frequency 1+ (for example, 2440 MHz>) in the microwave band, and a second frequency that is slightly different from the first frequency f1. f2 (e.g. 2455MH2)
A second oscillation circuit 3 that oscillates is provided. and,
The first frequency f outputted from the first oscillation circuit 2 is amplified by the amplifier 4, remains unmodulated, and is output from the antenna 5 as an energy wave with the first frequency f1 as a carrier wave by vertical polarization, for example, to the response device. 6 will be sent. Further, the second frequency f2 outputted from the second oscillation circuit 3 is modulated by the grip width using the interrogation signal in the modulation circuit 7, and is further amplified by the amplifier 8, and the second frequency f2 is outputted from the antenna 9 by the horizontally polarized wave. The interrogation signal wave is transmitted to the response device 6 as a carrier wave. The interrogation device 1 receives a second harmonic 2f1 of the first frequency f transmitted from the response device 6.
An antenna 1O is provided for receiving a response signal wave using the carrier wave as a carrier wave. A demodulated response signal is received and demodulated from the response signal wave received by the antenna IO via a bandpass filter 11, a low noise block down converter 12, and a detection circuit 13. Note that the interrogation device 1 has a built-in microprocessor or the like (not shown), and identifies whether or not the demodulated response signal is appropriate for the interrogation signal.
Alternatively, an operation signal for performing a process or the like according to the demodulation response signal is outputted.

The response device 6 is provided with an antenna 14 that receives the energy waves transmitted from the antenna 5, and the energy waves received by the antenna 14 are converted into DC power 10B through a rectifier circuit 15 and a low-pass filter 16. Output. This DC power is used as a driving power source for the response device 6. Further, the energy wave received by the antenna 14 is converted into a second harmonic wave 2f by a multiplier circuit 17 using a diode or the like,
The signal is applied to the modulation circuit 19 via the bandpass filter 18 as a carrier wave of the response signal wave. This modulation circuit 18
The harmonic wave 2f is amplitude-modulated by the response signal and is transmitted from the antenna 20 to the interrogation device 1 as a response signal wave. Further, the response device 6 is provided with an antenna 21 for receiving the interrogation signal wave transmitted from the antenna 9, and the interrogation signal wave received by the antenna 21 is sent through a detection circuit 22 and a high-pass filter 23 to a demodulated interrogation signal. is received and demodulated. The response device 6 has a built-in microprocessor (not shown), stores appropriate information, and calculates and outputs an appropriate response signal in response to the demodulated interrogation signal demodulated by the receiver 3. .

As shown in FIG. 6, the antennas 14 and 15 of the response device 6 are mounted on a low dielectric substrate with a longitudinal length λl/2, which is 1/2 of the wavelength λ of the energy wave, and an interrogation signal wave. A rectangular microstrip co-fit device 24 having a lateral length λ2/2 which is 1/2 of the wavelength λ2 is provided. Then, two diodes 25.2 are placed in the center of one horizontal side.
5 are connected in series, and the vertically polarized energy waves are rectified by these diodes 25.
DC power is output between both ends of this series connection.

Further, one end of a diode 25 is connected to the center of one vertical side, and a horizontally polarized interrogation signal wave is rectified and detected from the other end and output as a demodulated interrogation signal.

(Problem to be Solved by the Invention) By the way, in the case of the response device 6 described in ``2'', as the distance from the interrogation device 1 increases, the electric field strength of the energy waves that can be received by the response device 6 becomes weaker. Then, the capacity of the DC power obtained via the rectifier circuit 15 and the low-pass filter 16 decreases accordingly. As a result, a situation arises in which an appropriate operating voltage for the built-in microprocessor and the like cannot be obtained. Therefore, depending on the strength of the energy waves radiated from the antenna 5 of the interrogation device 1, the distance from the interrogation device 1 at which the response device 6 can properly communicate is limited.

Here, it is clear that when the response device 6 functions as an ID card or the like, the longer the communication distance, the more convenient it is. However, the strength of the energy waves that can be emitted from the interrogation device 1 is limited to 0.3 W or less in Japan due to laws and regulations. Furthermore, from the viewpoint of reducing the size and weight of the response device 6, there are limits to making the antenna 14 for receiving energy waves large or having an array shape. Therefore, the communicable distance of the response device 6 cannot be sufficiently obtained, and there is a growing desire to improve the communicable distance to a longer communicable distance.

Furthermore, in the communication system shown in FIG. 5, energy waves are transmitted as vertically polarized waves.

When the attitude of the response device 6 is tilted, the receiving microstrip resonator 24 is deviated from the vertical direction, causing a problem that vertically polarized energy waves cannot be received sufficiently. Therefore, the inventors of the present invention have devised that it is sufficient to transmit an energy wave as a circularly polarized wave, and to receive this in the response device 6 using a circularly polarized antenna. Furthermore, the interrogation signal wave is also transmitted as a circularly polarized wave rotating in the opposite direction to the energy wave, and one antenna device receives both the energy wave and the interrogation signal wave, and the power of the energy wave and the interrogation signal wave are combined. He devised that by converting the output into DC power, an even larger capacity of DC power could be obtained.

The present invention was made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a microwave power receiving device that receives a circularly polarized microwave signal and efficiently outputs DC power.

(Means for Solving the Problems) In order to achieve the above object, the microwave power receiving device of the present invention receives a microwave signal transmitted by circularly polarized waves from a wireless transmitting device and outputs DC power. A microwave power receiving device, in which two microstrip lines are arranged in a straight line with an interval between them, and a diode is interposed between both ends of the interval between the two microstrip lines. A microstrip resonator is formed by setting the dimension between both selling ends of the microstrip line to 1/2 of the wavelength of the microwave signal, including the impedance of the diode, and arranging a plurality of microstrip resonators in parallel. The diodes are electrically connected in series or parallel to form a microstrip resonator group, and two microstrip resonator groups are arranged in orthogonal directions, and the output power of these microstrip resonator groups is configured by connecting them in series or in parallel.

Alternatively, a plurality of microstrip resonators may be arranged in parallel, half of the diodes of these microstrip resonators facing in opposite directions, and electrically connected in series.

Furthermore, a plurality of the nine microstrip resonators are arranged in parallel, and the diodes of these microstrip resonators are interposed so as to face in the same direction, and are electrically connected in series to increase the output voltage. It may be configured.

The length of each microstrip line connected to the anode and cathode may be different depending on the difference in impedance when the diode is viewed from the anode, node side, and cathode side. Further, an electric circuit driven by DC power output from the microstrip resonator group is disposed on at least one of the front or back surface of the low dielectric substrate on which the microstrip resonator group is arranged. Also good. Further, a backward diode may be used as the diode.

(Function) A microstrip resonator is formed by arranging two microstrip lines in a straight line with a gap between them, and inserting a diode between the ends of the gap. A component in the direction in which the strip resonators are arranged is rectified by a diode and converted into DC power. Then, multiple microstrip resonators are arranged in parallel,
Since the microstrip resonator group is formed by connecting diodes in series or in parallel, a large capacity DC power is output from the microstrip resonator group. Further, since the two microstrip resonator groups are arranged in orthogonal directions and their output voltages are connected in series or in parallel, direct current power can be efficiently obtained as circularly polarized waves as components in two orthogonal directions. Moreover, DC power can also be obtained from circularly polarized waves in the direction of rotation.

In addition, if half of the diodes of multiple parallel microstrip resonators are interposed and connected in series with half of the diodes facing in opposite directions, it is possible to Each component is rectified by a diode and converted to DC power, increasing the capacity.

Furthermore, if the diodes of a plurality of parallel microstrip resonators are interposed and connected in series so as to face in the same direction, the output voltage can be increased.

If the length of the microstrip line to be connected is varied according to the difference in impedance between the cathode and anode of the diode, the diode and the microstrip line can be matched with a uniform structure. Further, if the electric circuit to be driven is disposed on the same low dielectric substrate as the microstrip resonator group, the transmission loss when supplying DC power is small and the structure is simple.

Furthermore, if a backward diode is used as the diode, the rectification efficiency is good, so that the power of the microwave signal can be converted and outputted into DC power more efficiently.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a plan view of the microwave power receiving device of the present invention, FIG. 2 is an equivalent circuit diagram for explaining the operation of the microstrip resonator of FIG. 1, and FIG. 1 is a block circuit diagram schematically showing a communication system to which a microwave power receiving device of the present invention is applied; FIG.

First, with reference to FIG. 3, a communication system in which the microwave power receiving device of the present invention is used will be described. In FIG. 3, the interrogation device 30 includes a first frequency f1 outputted from the first oscillation circuit 2, which is amplified by the amplifier 4 and applied to the hybrid link 31.
It is converted into two signals with different phases by 90' at I. and,
A circularly polarized wave is generated by these two signals, and the unmodulated circularly polarized wave antenna 32 transmits it as an energy wave to the response device 40 using, for example, left-handed circularly polarized wave. Further, the second frequency f2 output from the second oscillation circuit 3 is amplitude-modulated by the interrogation signal in the modulation circuit 7, further amplified by the amplifier 8, and given to the hybrid link 31.
0" is converted into two signals with different phases. Then, these two
A circularly polarized wave is generated from the signal, and the circularly polarized wave is transmitted from the circularly polarized antenna 32 to the response device 40 as an interrogation signal wave using a right-handed circularly polarized wave.

Note that in the hybrid link 31, the first and second frequencies f 1 , .

Further, the interrogation device 30 is provided with an antenna 33 that receives a response signal wave transmitted from the response device 40 and phase-modulated with the first frequency f1 or the response signal. The response signal wave received by the antenna 33 is transmitted to the band pass filter 34.
Accordingly, only the component of the first frequency f is extracted and provided to the homodyne detection circuit 35. This homodyne detection circuit 35 includes the first oscillation circuit 2 to the first ! The frequency f1 is given as a carrier wave for detection, and the response signal wave is subjected to homodyne detection and demodulated as a first demodulated response signal.

Furthermore, the interrogation device 30 includes a first
When phase modulating the frequency f1 of the response signal, a harmonic component is generated as if it were amplitude modulated by the response signal, and an antenna 1O is provided to receive this harmonic signal wave. Only the second harmonic component of the harmonic signal wave received by the antenna IO is extracted by the band pass filter 11, and further demodulated as a second demodulation response signal via the low noise block down converter 12 and the detection circuit 13. . Furthermore, a microprocessor (not shown) compares the first and second demodulated response signals, and if they match, it is confirmed that the response signal has been accurately demodulated without being affected by fading or noise. obtain.

The response device 40 is provided with a circularly polarized antenna 41 having a band capable of receiving both the energy wave and the interrogation signal wave transmitted from the circularly polarized antenna 32. Both the energy wave and the interrogation signal wave received by the circularly polarized antenna 41 are rectified by the rectifier circuit 42. Furthermore, a DC component is extracted from this rectified output via a low-pass filter 43, and is used as a DC power element B as a driving power source for the response device 40. Further, the Ig component is extracted from the rectified output via the high-pass filter 44, and is appropriately processed as a demodulated interrogation signal by a microprocessor or the like (not shown).

The response device 40 also includes an antenna 4 that receives energy waves transmitted from the circularly polarized antenna 32 of the interrogation device 30.
5 is provided separately. The energy wave as a carrier wave for the response signal wave received by the antenna 45 is given to the phase modulation circuit 4B, where it is phase modulated by the response signal output from a microprocessor, etc.
The response signal wave is transmitted from the inquiry device 30 to the interrogation device 30 as a response signal wave. During this modulation by the phase modulation circuit 46, harmonic components are generated as if amplitude modulated by the response signal, and these are simultaneously radiated from the antenna 45 as harmonic signal waves.

In this configuration, by passing the output of the rectifier circuit 42 of the response device 40 through the low-pass filter 43, DC power is output, which is a sum of the DC power due to the interrogation signal wave and the DC power due to the energy wave. Therefore, the capacity of this DC power is larger than that of the conventional device, and if this large capacity DC power is used as a driving power source for the response device 40, the response device 40 will be larger than that of the conventional device. The distance over which proper communication can be made is significantly longer.

Next, an embodiment of the microwave power receiving device of the present invention, which is commonly used as the circularly polarized antenna 41 of FIG. 3, will be described with reference to FIGS. 1 and 2.

In FIG. 1, the microwave power receiving device of the present invention as a circularly polarized antenna 41 has a plurality of line-shaped first micrometers on the surface of a low dielectric substrate 50 having a ground plate on the back surface. A first microstrip resonator group 55 is provided in which strip resonators 51, 51, . . . are arranged in parallel. Further, on the surface of the low dielectric substrate 50, a first
A second microstrip resonator group 56 has a plurality of line-shaped second microstrip resonators 52, 52, etc. arranged in parallel in a direction orthogonal to the microstrip resonators 51, 51, . will be placed. The first microstrip resonances 351 and 51- are formed by two microstrip lines arranged in a straight line with an interval between them, and a rectifying first diode 53, 5 between the ends of the interval. :] and - are inserted respectively. Then, half of the first diodes 53.5:J.- are interposed with their forward directions directed in one direction, and the other half are interposed with their forward directions directed in the opposite direction. Furthermore, the first diode 53°53...
are electrically connected in series, and the anode side of the series connection is grounded G to form a first microstrip resonator group 55.
is formed. Similarly, the second microstrip resonators 52, 52-... each have two microstrip lines arranged in a straight line with an interval between them, and a second rectifying resonator between the ends of the interval. Diode 54.54-・
・is interposed in each. Then, half of the diodes 54, 54, etc. of 7PJ2 face forward in one direction,
The other half are interposed with the forward direction in the opposite direction. Further, second diodes 54, 54- are electrically connected in series, and the anode side of the series connection is grounded G to form a second microstrip resonator group 56.

And the first and second diodes 53, 53...54
．． The cathode side of each series connection body of 54... is connected. That is, the output powers of the first and second microstrip resonator groups 55 and 56 are connected in parallel. Furthermore, this connection point on the cathode side is connected to a low-pass filter 43 consisting of a coil connected in series and a capacitor connected in parallel, and a high-pass filter 44 consisting of a capacitor connected in series. be done.

Here 5 first and second microstrip resonators 51.
As shown in Figure 2, the equivalent circuit of the first and second diodes 53.53.++, 54.54-. a parallel connection body is connected in series with lead inductance L3 and lead resistance R3,
This series connection body and case capacitance Cc are connected in parallel. Then, depending on the direction of the current flowing due to resonance,
Junction resistance RJ is switched to zero or to infinity.

The first and second microstrip resonators 51.
51-. 52.52- is the first and second diode 53
．． 53-. A resonance characteristic having a certain frequency width is obtained by the impedance of 54.54-1 and the impedance of the microstrip line connected to both ends thereof. In addition, first and second diodes 53, 53-. 54.54- has a junction resistance R, which is switched to zero or infinite depending on the current direction, and has a rectifying effect, and the first and second diodes 53.5
3-. DC power is generated across the 54.54-.

Therefore, the first and second microstrip resonators 51.
The dimensions between both ends of 51-, 52.52- are the first and second diodes 53.53-54.54 interposed in the center.
The effective length, taking into consideration the impedance of..., is set to be approximately 1/2 of the average wavelength of the first and second frequencies f, , f2. Furthermore, first and second diodes 53.
5: ]-, 54, 54- are the first and second diodes 53.
, 54-... are matched by making the lengths of the microstrip lines connected to both ends of the microstrip lines different.

In this configuration, the circularly polarized antenna 41 and the rectifier circuit 42 are configured by the first and second microstrip resonator groups 55 and 56. Then, the first and second microstrip resonators 51, 51-. Components in the arrangement direction of 52, 52-... resonate with each other, and both left-handed and right-handed circularly polarized waves can be received. Furthermore, the current of the resonant signal flows through the first and second diodes 53, 53-. Since it is rectified at 54°54..., direct current power can be obtained efficiently without attenuation for transmission. Moreover, the first and second diodes 53
．． 53-. 54. Half of the 54- turned to one side,
Since the other half is interposed with the forward direction facing the other half, the circularly polarized wave components whose directions are opposite in the arrangement direction of the microstrip co-occupant 1rI55.55 are rectified by the diodes and output as DC power. Ru. Also, if the first and second diodes 53, 53, -54, 54, etc. are oriented in the same direction and are connected in series, the rectified voltage will be connected in series, increasing the output voltage. be able to.

Note that diodes arranged in the same direction may be connected in parallel to a plurality of parallel microstrip resonators to increase the output power capacity.

Further, if the microstrip resonator groups 55 and 56 are connected in parallel as in the embodiment, the output power capacity increases, but the output voltage may be increased by connecting the microstrip fiW groups 55 and 58 in series.

Furthermore, an example of a specific structure of the antenna 45 and phase modulator 46 of the response device 40 will be briefly explained with reference to FIG.

A microstrip resonator 60 that resonates at a first frequency f is disposed on the surface of the low dielectric substrate 50. This microstrip resonator 60.

Two microstrip lines are arranged in a straight line with an interval between them, and a variable capacitance diode 6I, for example, is interposed between both ends of the interval.

The anode of the variable capacitance diode 61 is grounded G, and a response signal is applied to the cathode.

With this configuration, the antenna 45 and the phase modulator 46 are configured. Then, the capacitance of the variable capacitance diode 61 changes according to the response signal, and the microstrip resonator 6
The effective length of 0 is switched to 1/2 of the wavelength of the first frequency f1, which is shifted from this. Therefore, if the effective length is 1/2 of the wavelength of the first frequency f1, the first frequency f resonates in the microstrip resonator 60 and is further radiated.

Furthermore, in a state where the effective length is not 1/2 of the wavelength of the first frequency f1, the first frequency f1 does not resonate in the microstrip resonator 60, but is reflected by other surrounding structures. Therefore, the length of the propagation path differs and the phase changes due to the difference between the position where the light is radiated with resonance and the position where it is reflected without resonance. This phase-modulated signal is then transmitted to the interrogation device 30 as a response chair branch. Further, the variable capacitance diode 61 is a nonlinear element, and generates harmonic components when current flows therethrough. Therefore, due to the nonlinearity of the variable capacitance diode 61, harmonic components are strongly generated in a state where the first frequency f resonates.

Further, the generation strength of harmonic components differs between resonance and non-resonance. Therefore, harmonic components are radiated as if they had been amplitude modulated by the response signal.

FIG. 4 is a plan view of another embodiment of the microwave power receiving device of the present invention. In FIG. 4, two orthogonal microstrip resonator groups 71 and 72 are formed on the surface of a low dielectric substrate 70 with a ground plate disposed on the back surface in the direction of creation with respect to the periphery of the low dielectric substrate 70. will be placed. The output voltages of these microstrip resonator groups 71 and 72 are connected in parallel, and are applied to a driving power source via a low-pass filter 73 to an electric circuit 74 to be driven disposed on the same low dielectric substrate 70. given as. This electric circuit 74 may be provided on the back surface of the low dielectric substrate 70 by partially removing the ground plate provided on the back surface.

In such a configuration, the microstrip resonator group 71
．． Since the DC power converted and output from 72 is applied as a driving power source to the electric circuit 74 disposed on the same low dielectric substrate 70, transmission loss can be minimized. Moreover, since the low dielectric substrate 70 is also used as a substrate for the electric circuit 74, the structure is simple and the space can be reduced, which is suitable for reducing the size and weight of the response device 40.

(Effects of the Invention) Since the microwave power receiving device of the present invention is configured as described above, it produces the effects described below.

2B In the microwave power receiving device according to claim 1,
DC power is efficiently output from circularly polarized waves in either direction of rotation.

Further, in the microwave power receiving device according to claim 2, the component of the resonating circularly polarized wave in the opposite direction in the arrangement direction of the microstrip resonator is rectified by the diode arranged in the opposite direction. It is possible to efficiently convert circularly polarized power into DC power.

Furthermore, in the microwave power receiving device according to claim 3, the output voltage can be increased by connecting diodes arranged in the same direction in series, and the diodes interposed in the microstrip resonator can be connected in series. The output voltage can be easily adjusted by changing the number of series connections.

Further, in the microwave power receiving device according to claim 4, impedance can be easily matched by making the lengths of the microstrip lines connected to the diodes different between the anode side and the cathode side. .

In the microwave power receiving device according to the fifth aspect of the present invention, electric circuits to be driven are arranged on the same low dielectric substrate, thereby reducing power loss for transmission. Moreover, since the structure is rlR41-, the number of parts is small, and it can be constructed at low cost.

Furthermore, a micro power reducing receiver (1j
In the device, the power of the microwave signal is efficiently converted to DC power by the backward diode, and DC power with a large capacity can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the microwave power receiving device of the present invention, FIG. 2 is an equivalent circuit diagram for explaining the operation of the microstrip resonator of FIG. 1, and FIG. FIG. 4 is a block circuit diagram showing an outline of a preferred communication system in which the microwave power receiving device of the present invention is used; FIG. 4 is a plan view of another embodiment of the microwave power receiving device of the present invention; FIG. 5 is a diagram showing an outline of a conventional communication system, and FIG. 6 is a diagram showing an example of an antenna used in FIG. 5. 5+, 52: Microstrip resonator, 53.5
4: Diode, 55, 56, 71, 72: Microstrip resonator group, 70: Low-talk telephone board, 74: Electric circuit.

Claims (6)

[Claims] (1) A microwave power receiving device that receives a microwave signal transmitted by circularly polarized waves from a wireless transmitter and outputs DC power, in which two microstrip lines are arranged in a straight line with an interval between them. At the same time, a diode is interposed between both ends of the interval between the microstrip lines, and the dimension between the ends of the two straight microstrip lines, including the impedance of the diode, is 1 of the wavelength of the microwave signal. /2 to form a microstrip resonator, a plurality of these microstrip resonators are arranged in parallel, and the diodes are electrically connected in series or parallel to form a microstrip resonator group, and this microstrip resonator A microwave power receiving device characterized in that two microstrip resonator groups are arranged in orthogonal directions, and the output power of these microstrip resonator groups are connected in series or in parallel. (2) A plurality of the microstrip resonators are arranged in parallel, and half of the diodes of these microstrip resonators are interposed so as to face in opposite directions, and are electrically connected in series. The microwave power receiving device described above. (3) A plurality of the microstrip resonators are arranged in parallel, and the diodes of these microstrip resonators are interposed so as to face in the same direction, and are electrically connected in series to increase the output voltage. The microwave power receiving device according to claim 1. (4) Any one of claims 1 to 3, wherein the length of each microstrip line to which the anode and cathode are connected differs depending on the difference in impedance when the diode is viewed from the anode side and the cathode side. A microwave power receiving device. (5) An electric circuit driven by DC power output from the microstrip resonator group is disposed on at least one of the front or back surface of the low dielectric substrate on which the microstrip resonator group is arranged. The microwave power receiving device according to any one of claims 1 to 4, characterized by: (6) The microwave power receiving device according to any one of claims 1 to 5, wherein a backward diode is used as the diode.