rectifier

Abstract

A rectifier (10) comprises: a rectifier circuit (11) that is configured utilizing a plurality of diodes (201 to 204) and that on receiving input of a rectified wave generates a DC component; and a plurality of line elements connected to the rectifier circuit (11). The plurality of diodes (201-204) contains a first diode (201), a second diode (202), a third diode (203), and a fourth diode (204). The plurality of line elements are each an even-order short-circuit element (301-304) the impedance of which goes to zero at at least one among even-order harmonics of the rectified wave, thereby smoothing the output of the rectifier circuit. The plurality of line elements include: a first element, one end of which is connected to the first diode and the other end of which is open; a second element, one end of which is connected to the second diode and the other end of which is open; a third element, one end of which is connected to the third diode and the other end of which is open; and a fourth element, one end of which is connected to the fourth diode and the other end of which is open.

Description

Technical Field

[0001] The present disclosure relates to a rectifier that converts high frequency to direct current.

Background Art

[0002] As a rectifier that converts high frequency in the microwave band to direct current, a bridge rectifier in which four diodes are arranged in a bridge configuration is known. As such a bridge rectifier, there is one that uses a shunt capacitor that becomes a short-circuit state for even harmonics (for example, Patent Document 1). The shunt capacitor is arranged between the output side of the diodes connected in bridge and the ground, and is a plurality of capacitors each connected in shunt.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the frequency band of the fundamental wave in the wave to be rectified exceeds 20 GHz, it becomes difficult for the chip capacitor connected to the output side of the diodes connected in bridge to become a short-circuit state for even harmonics due to the influence of the inductive component. Also, in a high frequency band, the performance of the capacitor is greatly affected by variations. As a result, the performance difference between rectifiers becomes large, and the quality of the rectifier deteriorates.

[0005] [[ID=,38]] The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a rectifier that can obtain high conversion efficiency with a simple circuit configuration and suppress variations in performance.

Means for Solving the Problems

[0006] To achieve the above objective, the rectifier according to this disclosure comprises a rectifier circuit and a plurality of line members. The rectifier circuit is configured using a plurality of diodes and receives the wave to be rectified as input to generate a DC component. The plurality of diodes include a first diode and a third diode, whose anode is connected to the input side of the rectifier circuit and whose cathode is connected to the output side of the rectifier circuit, and a second diode and a fourth diode, whose cathode is connected to the input side of the rectifier circuit and whose anode is connected to the output side of the rectifier circuit. Each of the plurality of line members is an even-order short-circuit member that has zero impedance in at least one of the even-order harmonics of the wave to be rectified and smooths the output of the rectifier circuit, with one end connected to a diode and the other end open. [Effects of the Invention]

[0007] According to this disclosure, each of the multiple line members has zero impedance in at least one even-order harmonic of the rectified wave, smoothing the output of the rectifier circuit. This allows for high conversion efficiency with a simple circuit configuration and suppresses variations in performance. [Brief explanation of the drawing]

[0008] [Figure 1] A diagram showing an example of the configuration of a rectifier according to Embodiment 1. [Figure 2] This figure shows the operating state and current path of the diode in the rectifier circuit of the rectifier according to Embodiment 1. [Figure 3] This figure shows another operating state and current path of the diode in the rectifier circuit of the rectifier according to Embodiment 1. [Figure 4] This figure shows the time waveform of the current flowing through the diode in the rectifier according to Embodiment 1. [Figure 5] This figure shows the time waveform of the current flowing through the diode in the rectifier according to Embodiment 1. [Figure 6] A diagram showing the current path of even-order harmonics in a rectifier according to Embodiment 1. [Figure 7] A diagram showing the current path of even-order harmonics in a rectifier according to Embodiment 1. [Figure 8] A diagram showing an example configuration of a rectifier according to Embodiment 1. [Figure 9] A diagram showing another example configuration of the rectifier according to Embodiment 1. [Figure 10] A diagram showing yet another configuration example of the rectifier according to Embodiment 1. [Figure 11] A diagram showing an example of the rectifier configuration according to Embodiment 2. [Figure 12] Diagram illustrating the problems in the rectifier according to Embodiment 1. [Figure 13] A diagram showing another configuration example of the rectifier according to Embodiment 2. [Figure 14] A diagram showing yet another configuration example of the rectifier according to Embodiment 2. [Figure 15] A diagram showing an example of the configuration of a rectifier according to Embodiment 3. [Figure 16] A diagram showing another configuration example of the rectifier according to Embodiment 3. [Modes for carrying out the invention]

[0009] The rectifier according to the embodiment of this disclosure will be described below. In the figures, the same or equivalent parts are denoted by the same reference numerals.

[0010] Embodiment 1. FIG. 1 shows a configuration example of a rectifier 10 according to Embodiment 1 of the present disclosure. The rectifier 10 includes a rectifier circuit 11 using diodes, and a plurality of even-order short-circuit means 301 to 304 connected to the rectifier circuit 11. The rectifier 10 also includes input terminals 100 and 101, and an output terminal 500. The input terminals 100 and 101 are high-frequency input terminals to which a high-frequency signal is differentially input. The rectifier circuit 11 has four diodes 201 to 204 arranged in a bridge configuration as a plurality of diodes. The diode 201 is the first diode in the rectifier circuit 11. The diode 202 is the second diode in the rectifier circuit 11. The diode 203 is the third diode in the rectifier circuit 11. The diode 204 is the fourth diode in the rectifier circuit 11. The rectifier circuit 11 converts a high-frequency rectified wave input to the input terminals 100 and 101 to generate a DC component. The output terminal 500 outputs single-phase DC. In the rectifier circuit 11, single-phase DC is output between the output terminal 500 and the ground GND. Therefore, the ground side connected to the ground GND is also the output side of the rectifier circuit 11.

[0011] When a high-frequency rectified wave is input to the input terminals 100 and 101 and is full-wave rectified by the rectifier circuit 11, the even-order short-circuit means 301 to 304 become short-circuited (impedance is zero) in at least one of the even-order harmonics of the rectified wave generated by the full-wave rectification. The even-order short-circuit means 301 to 304 also have a smoothing function for smoothing the output of the rectifier circuit 11. Note that the harmonics of the rectified wave are signal waves included in the rectified signal and having a frequency that is an integer multiple of the frequency of the rectified wave.

[0012] In the rectifier circuit 11, the connections of diodes 201 to 204 are determined considering the board wiring layout. For example, the anode of diode 201 is connected to input terminal 100 on the input side of the rectifier circuit 11. The cathode of diode 201 is connected to connection point 510 via transmission line 401 on the output side of the rectifier circuit 11. The anode of diode 203 is connected to input terminal 101 on the input side of the rectifier circuit 11. The cathode of diode 203 is connected to connection point 510 via transmission line 403 on the output side of the rectifier circuit 11. Connection point 510 is connected to output terminal 500 via transmission line 410. The rectifier 10 outputs DC from output terminal 500. The anode of diode 202 is connected to connection point 511 via transmission line 402 on the ground side of the rectifier circuit 11. The cathode of diode 202 is connected to input terminal 100 on the input side of rectifier circuit 11. The anode of diode 204 is connected to connection point 511 via transmission line 404 on the ground side of rectifier circuit 11. The cathode of diode 204 is connected to input terminal 101 on the input side of rectifier circuit 11. Connection point 511 is grounded by being connected to ground GND on the back of the circuit board via via 411.

[0013] Rectifier 10 is applicable to a rectenna. A rectenna is an antenna with a rectifier that converts high-frequency microwaves received by an antenna to direct current. This conversion from high frequency to direct current is also called RF-DC conversion. Rectennas are used in the power receiving section of wireless power transmission (WPT). To obtain a highly efficient transmission system, the rectifier constituting the rectenna is required to have high efficiency in RF-DC conversion. To achieve high efficiency in microwave rectifiers, appropriate processing of harmonics is necessary. Harmonics in a rectifier are generated by the switching between on and off states of the diode. Rectifier 10 achieves high efficiency in RF-DC conversion with a simple circuit configuration.

[0014] Next, regarding the four diodes 201 to 204 included in the rectifier circuit 11, the operating state and current path when a high-frequency rectified wave is input to the input terminals 100 and 101 will be described. The rectifier circuit 11 is a bridge rectifier circuit configured using a plurality of diodes 201 to 204 as bridge-connected diodes. Such a bridge rectifier circuit is included in a full-wave rectifier circuit. The rectifier circuit 11 generates a DC component when a high-frequency rectified wave is input.

[0015] FIG. 2 shows the operating state and current path of the diodes 201 to 204 in the rectifier circuit 11 when the input terminal 100 side is at a positive voltage in the AC voltage supplied to the input terminals 100 and 101. In the positive half cycle of the high-frequency signal supplied to the input terminals 100 and 101, the diodes 201 and 204 are forward-biased. At this time, the operating state of the diode 201 is the on state 201S1. The operating state of the diode 204 is the on state 204S1. On the other hand, the diodes 202 and 203 are reverse-biased. At this time, the operating state of the diode 202 is the off state 202S1. The operating state of the diode 203 is the off state 203S1. Arrow A01 indicates the current flowing from the input terminal 100 into the rectifier circuit 11. This current flows out from the rectifier circuit 11 to the output terminal 500 as the current indicated by arrow A02 through the diode 201, transmission line 401, connection point 510, and transmission line 410. Arrow A03 indicates the current flowing from the ground GND into the rectifier circuit 11. This current flows out from the rectifier circuit 11 to the input terminal 101 as the current indicated by arrow A04 through the connection point 511, transmission line 404, and diode 204.

[0016] Figure 3 shows the operating states and current paths of diodes 201-204 in the rectifier circuit 11 when the AC voltage supplied to input terminals 100 and 101 is negative on the input terminal 100 side. During the negative half-period of the high-frequency signal supplied to input terminals 100 and 101, diodes 201 and 204 are biased in the reverse direction. At this time, the operating state of diode 201 is the off state 201S2. The operating state of diode 204 is the off state 204S2. On the other hand, diodes 202 and 203 are biased in the forward direction. At this time, the operating state of diode 202 is the on state 202S2. The operating state of diode 203 is the on state 203S2. Arrow A11 indicates the current flowing from input terminal 101 to the rectifier circuit 11. This current flows out of the rectifier circuit 11 to the output terminal 500 as the current indicated by arrow A12, via diode 203, transmission line 403, connection point 510, and transmission line 410. Arrow A13 indicates the current flowing from ground GND into the rectifier circuit 11. This current flows out of the rectifier circuit 11 to the input terminal 100 as the current indicated by arrow A14, via connection point 511, transmission line 402, and diode 202.

[0017] Figure 4 shows the time waveform of the current flowing through diodes 201 and 203. In Figure 4, the direction of the current is positive from the anode to the cathode for both diodes 201 and 203. The current flowing through each diode 201 and 203 has a half-wave rectified waveform. In this case, the half-wave rectified waveform includes a DC component, even-order harmonic components, and odd-order harmonic components. At the output side of the rectifier circuit 11, the sum of the currents flowing through diodes 201 and 203 flows out. This sum of currents has a full-wave rectified waveform. The full-wave rectified waveform includes a DC component and even-order harmonic components, but does not include odd-order harmonic components. Therefore, the odd-order harmonics of the rectified wave do not flow out from the rectifier circuit 11 to the output terminal 500.

[0018] The currents flowing through diodes 202 and 204, like those through diodes 201 and 203, have a half-wave rectified waveform. The sum of the currents flowing through diodes 202 and 204 flows through the ground side of the rectifier circuit 11. This sum of currents has a full-wave rectified waveform. A full-wave rectified waveform contains a DC component and even-order harmonic components, but does not contain odd-order harmonic components. Therefore, odd-order harmonics of the rectified wave do not flow from ground GND into the rectifier circuit 11.

[0019] Figure 5 shows the time waveforms of the currents flowing through diodes 201 and 202. In Figure 5, the direction of the current is positive from cathode to anode for diode 201, while for diode 202, the direction is positive from anode to cathode. In this case, the sum of the currents flowing through diodes 201 and 202 will be positive when flowing from the rectifier circuit 11 to the input terminal 100. This sum of currents can be expressed using an odd function. The sum of the currents flowing through diodes 201 and 202 does not contain even-order harmonic components.

[0020] For diode 203, the positive direction of the current is defined as the direction from cathode to anode. For diode 204, the positive direction of the current is the direction from anode to cathode. Therefore, the sum of the currents flowing through diodes 203 and 204 will be a positive value when the current flows from the rectifier circuit 11 to the input terminal 101. The sum of the currents flowing through diodes 203 and 204 can also be expressed using an odd function, similar to the case of diodes 201 and 202.

[0021] When even-order short-circuiting means 301-304 are not present, the rectifier circuit 11, acting as a bridge rectifier, converts half of each waveform cycle into a DC signal containing pulsations. The full-wave rectifier rectifies both the positive and negative voltage sides of the waveform, resulting in two pulses per cycle. This causes the frequency of the pulsations to be twice the frequency of the input signal. The output terminal 500 outputs the DC converted by the rectifier circuit 11.

[0022] The connection point 510, where the cathodes of diode 201 and diode 203 are connected, is the output of the rectifier 10. When even-order short-circuiting means 301 to 304 are not provided, the output waveform at output terminal 500 includes a DC component and an even-order harmonic component. Leakage of even-order harmonics to the output side reduces the efficiency of RF-DC conversion. In addition, if even-order harmonics are present, it becomes impossible or difficult to adequately smooth the DC output of the rectifier 10. When the rectified wave is a high frequency exceeding 20 GHz, the even-order harmonics will exceed 40 GHz. In this case, the influence of the inductive component of the capacitor becomes large, making it difficult to short-circuit the output side of the bridged diodes with the capacitor at the even-order harmonics.

[0023] The rectifier 10 according to Embodiment 1 includes a plurality of even-order short-circuiting means 301 to 304, each having one end connected to the output side or ground side of a bridged diode and the other end open. The rectifier 10 can smooth the output by preventing leakage of even-order harmonics to the output side. The even-order short-circuiting means 301 is a first member as a first even-order short-circuiting member connected to the cathode of the diode 201 and short-circuiting even-order harmonics on the output side of the rectifier circuit 11. The even-order short-circuiting means 302 is a second member as a second even-order short-circuiting member connected to the anode of the diode 202 and short-circuiting even-order harmonics on the ground side of the rectifier circuit 11. The even-order short-circuiting means 303 is a third member as a third even-order short-circuiting member connected to the cathode of the diode 203 and short-circuiting even-order harmonics on the output side of the rectifier circuit 11. The even-order short-circuiting means 304 is connected to the anode of the diode 204 and is a fourth even-order short-circuiting member that short-circuits even-order harmonics on the ground side of the rectifier circuit 11. Short-circuiting with respect to even-order harmonics is also called an even-order short-circuit.

[0024] Even-order short-circuiting means 301 short-circuits even-order harmonics at the cathode of diode 201 (making the impedance zero). Even-order short-circuiting means 302 short-circuits even-order harmonics at the anode of diode 202. Even-order short-circuiting means 303 short-circuits even-order harmonics at the cathode of diode 203. Even-order short-circuiting means 304 short-circuits even-order harmonics at the anode of diode 204. By generating these even-order short-circuits, the rectifier 10 equipped with even-order short-circuiting means 301 to 304 prevents leakage of even-order harmonics to the output side and smooths the output.

[0025] Figure 6 shows the current path of even-order harmonics in the rectifier 10, including even-order short-circuit means 301-304, when the high-frequency signal supplied to input terminals 100 and 101 is in a positive half-period. At this time, diode 201 is in operating state 201S3, and diode 204 is in operating state 204S3. The multiple arrows drawn in the squares at the positions of diodes 201 and 204 indicate that even-order harmonic currents such as DC current, 2nd harmonic current, 4th harmonic current, and 6th harmonic current are flowing from left to right. The direction of the currents other than DC current may not coincide with the actual direction. On the other hand, diode 202 is in the off state 202S3, and diode 203 is in the off state 203S3. In operating state 201S3, the anode and cathode of diode 201 are short-circuited. Furthermore, the even-order harmonics generated in diode 201 are absorbed by the even-order short-circuit means 301. Therefore, even-order harmonics generated in diode 201 are confined within diode 201. In operating state 204S3, the anode and cathode of diode 204 are short-circuited. Furthermore, even-order harmonics generated in diode 204 are absorbed by the even-order short-circuiting means 304. Therefore, even-order harmonics generated in diode 204 are confined within diode 204.

[0026] Figure 7 shows the current path of even-order harmonics in the rectifier 10, including even-order short-circuit means 301-304, when the high-frequency signal supplied to input terminals 100 and 101 is in a negative half-period. At this time, diode 202 is in operating state 202S4, and diode 203 is in operating state 203S4. The multiple arrows drawn in the squares at the positions of diodes 202 and 203 indicate that even-order harmonic currents such as DC current, 2nd harmonic current, 4th harmonic current, and 6th harmonic current are flowing from left to right. The direction of the currents other than DC current may not coincide with the actual direction. On the other hand, diode 201 is in off state 201S4, and diode 204 is in off state 204S4. In operating state 202S4, the anode and cathode of diode 202 are short-circuited. Furthermore, the even-order harmonics generated in diode 202 are absorbed by the even-order short-circuit means 302. Therefore, even-order harmonics generated in diode 202 are confined within diode 202. In operating state 203S4, the anode and cathode of diode 203 are short-circuited. Furthermore, even-order harmonics generated in diode 203 are absorbed by the even-order short-circuiting means 303. Therefore, even-order harmonics generated in diode 203 are confined within diode 203.

[0027] In each cycle of the high-frequency signal, each diode 201-204 switches between an on state and an off state. Each even-order short-circuiting means 301-304, positioned corresponding to each diode 201-204, short-circuits at least one even-order harmonic on the output side or ground side of the rectifier circuit 11. Therefore, the even-order harmonics generated by the switching of each diode 201-204 can be confined to the terminals to which each diode 201-204 is connected. In this way, the rectifier 10 can achieve high efficiency in RF-DC conversion by preventing leakage of even-order harmonics to the output side. Furthermore, due to the smoothing function of the even-order short-circuiting means 301-304, a DC output with suppressed pulsation caused by even-order harmonics is output at the output terminal 500.

[0028] Figure 8 shows an example configuration of the rectifier 10. In Figure 8, the even-order short-circuit means 301 to 304 are each a single open stub using a transmission line. The even-order short-circuit means 301 is composed of a line member 311 having an electrical length L1 of one-quarter wavelength with respect to the second harmonic of the wave being rectified. The even-order short-circuit means 302 is composed of a line member 312 having an electrical length L1 of one-quarter wavelength with respect to the second harmonic of the wave being rectified. The even-order short-circuit means 303 is composed of a line member 313 having an electrical length L1 of one-quarter wavelength with respect to the second harmonic of the wave being rectified. The even-order short-circuit means 304 is composed of a line member 314 having an electrical length L1 of one-quarter wavelength with respect to the second harmonic of the wave being rectified.

[0029] In the even-order short-circuit means 301, which is arranged in correspondence with diode 201, one end of the line member 311 is connected to the cathode of diode 201 and the other end is open. In the even-order short-circuit means 302, which is arranged in correspondence with diode 202, one end of the line member 312 is connected to the anode of diode 202 and the other end is open. In the even-order short-circuit means 303, which is arranged in correspondence with diode 203, one end of the line member 313 is connected to the cathode of diode 203 and the other end is open. In the even-order short-circuit means 304, which is arranged in correspondence with diode 204, one end of the line member 314 is connected to the cathode of diode 204 and the other end is open. In the configuration shown in Figure 8, the line members 311 and 313 located on the output side of the rectifier circuit 11, and the line members 312 and 314 located on the ground side of the rectifier circuit 11, short-circuit the second harmonic of the rectified wave.

[0030] When the bridged diodes in a full-wave rectifier circuit are switched between the on and off states, the lower the harmonic order, the higher the harmonic level. A lower harmonic order has a greater impact on the efficiency of RF-DC conversion. The rectifier 10 shown in Figure 8 prevents leakage of the second harmonic, which has the greatest impact on the efficiency of RF-DC conversion, to the output side.

[0031] Each even-order short-circuiting means 301-304 in Figure 8 is an even-order short-circuiting member constructed using a single transmission line member. The output of the rectifier circuit 11 can be smoothed by the even-order short-circuiting means 301-304, and as a result, a capacitor is not required as a smoothing element. This allows for high conversion efficiency with a simple circuit configuration when rectifying high frequencies exceeding 20 GHz. Furthermore, the rectifier 10 without a capacitor can reduce performance variations. The simple configuration that prevents leakage of second harmonics to the output side enables miniaturization of the device.

[0032] Figure 9 shows another configuration example of the rectifier 10. In Figure 9, the even-order short-circuit means 301 to 304 each include a number of open stubs corresponding to the even-order harmonics (2nd, 4th, 6th, etc.) of the wave being rectified. The even-order short-circuit means 301 includes line members 321 and 331 in addition to line member 311. Line member 321 has an electrical length L2 of one-quarter wavelength for the 4th harmonic of the wave being rectified. Line member 331 has an electrical length L3 of one-quarter wavelength for the 6th harmonic of the wave being rectified. The even-order short-circuit means 302 includes line members 322 and 332 in addition to line member 312. Line member 322 has an electrical length L2 of one-quarter wavelength for the 4th harmonic of the wave being rectified. Line member 332 has an electrical length L3 of one-quarter wavelength for the sixth harmonic of the rectified wave. The even-order short-circuit means 303 includes line members 323 and 333 in addition to line member 313. Line member 323 has an electrical length L2 of one-quarter wavelength for the fourth harmonic of the rectified wave. Line member 333 has an electrical length L3 of one-quarter wavelength for the sixth harmonic of the rectified wave. The even-order short-circuit means 304 includes line members 324 and 334 in addition to line member 314. Line member 324 has an electrical length L2 of one-quarter wavelength for the fourth harmonic of the rectified wave. Line member 334 has an electrical length L3 of one-quarter wavelength for the sixth harmonic of the rectified wave. Each of the even-order short-circuiting means 301 to 304 may include an open stub having an electrical length of one-quarter wavelength for even-order harmonics of the 8th order or higher. Each of the even-order short-circuiting means 301 to 304 may include two open stubs, each having an electrical length of one-quarter wavelength for the 2nd and 4th even-order harmonics, respectively. Each of the even-order short-circuiting means 301 to 304 may include multiple open stubs, each having an electrical length of one-quarter wavelength for each of a plurality of even-order harmonics.

[0033] In Figure 9, the line members 311 to 314 are short-circuited for the second harmonic, similar to the configuration in Figure 8. In the even-order short-circuit means 301, which is arranged in correspondence with diode 201, one end of line members 321 and 331 is connected to the cathode of diode 201 and the other end is open. In the even-order short-circuit means 302, which is arranged in correspondence with diode 202, one end of line members 322 and 332 is connected to the anode of diode 202 and the other end is open. In the even-order short-circuit means 303, which is arranged in correspondence with diode 203, one end of line members 323 and 333 is connected to the cathode of diode 203 and the other end is open. In the even-order short-circuit means 304, which is arranged in correspondence with diode 204, one end of line members 324 and 334 is connected to the anode of diode 204 and the other end is open. In the configuration shown in Figure 9, the line members 321 and 323 located on the output side of the rectifier circuit 11, and the line members 322 and 324 located on the ground side of the rectifier circuit 11, are short-circuited with respect to the fourth harmonic of the rectified wave. In the configuration shown in Figure 9, the line members 331 and 333 located on the output side of the rectifier circuit 11, and the line members 332 and 334 located on the ground side of the rectifier circuit 11, are short-circuited with respect to the sixth harmonic of the rectified wave. In addition, each even-order short-circuiting means 301 to 304 may include line members that short-circuit with respect to any even-order harmonic.

[0034] Each even-order short-circuiting means 301 to 304 in Figure 9 is an even-order short-circuiting member composed of multiple line members. In the case of Figure 9, the rectifier 10 has a larger circuit size than in the case of Figure 8. On the other hand, the rectifier 10 in Figure 9 is highly effective in preventing leakage of even-order harmonics to the output side. Therefore, the rectifier 10 having the configuration of Figure 9 has higher RF-DC conversion efficiency than the configuration of Figure 8.

[0035] Figure 10 shows yet another configuration example of the rectifier 10. In Figure 10, the rectifier circuit 11 is connected from connection point 511 to output terminal 501 via transmission line 412. Output terminals 500 and 501 are DC output terminals that output DC differentially.

[0036] In the configuration of Figure 10, the connection point 511, which is connected to the anode of diode 202 and the anode of diode 204, provides the output of the rectifier 10. The anode of diode 202 is connected to the connection point 511 via the transmission line 402 on the output side of the rectifier circuit 11. The anode of diode 204 is connected to the connection point 511 via the transmission line 404 on the output side of the rectifier circuit 11. The connection point 511 is connected to the output terminal 501 via the transmission line 412. In the configuration of Figure 10, the configuration in which the anode of diode 201 and the cathode of diode 202 are connected to the input terminal 100, the configuration in which the anode of diode 202 and the cathode of diode 204 are connected to the input terminal 101, and the configuration of the cathode side of diodes 201 and 203 are the same as in the configuration of Figure 1.

[0037] The rectifier 10 in Figure 10 includes a plurality of even-order short-circuiting means 301 to 304, each having one end connected to the output side of a bridged diode and the other end open. The even-order short-circuiting means 301 is connected to the cathode of diode 201 and is a first even-order short-circuiting member that short-circuits even harmonics on the output side of the rectifier circuit 11. The even-order short-circuiting means 302 is connected to the anode of diode 202 and is a second even-order short-circuiting member that short-circuits even harmonics on the output side of the rectifier circuit 11. The even-order short-circuiting means 303 is connected to the cathode of diode 203 and is a third even-order short-circuiting member that short-circuits even harmonics on the output side of the rectifier circuit 11. The even-order short-circuiting means 304 is connected to the anode of diode 204 and is a fourth even-order short-circuiting member that short-circuits even harmonics on the output side of the rectifier circuit 11.

[0038] In Figure 10, each even-order short-circuiting means 301 to 304 is an even-order short-circuiting member composed of one or more line members. Each even-order short-circuiting means 301 to 304 may include a line member that short-circuits for any even-order harmonic. In the configuration of Figure 10, the output of the rectifier circuit 11 can be smoothed by the even-order short-circuiting means 301 to 304, and as a result, the rectifier 10 does not require a capacitor as a smoothing element. This allows the rectifier 10 to achieve high conversion efficiency with a simple circuit configuration. Furthermore, a rectifier 10 without a capacitor can suppress variations in performance.

[0039] As described above, the rectifier 10 comprises a rectifier circuit 11 composed of a plurality of diodes 201 to 204, and even-order short-circuit means 301 to 304 connected to the rectifier circuit 11. The rectifier circuit 11 receives the wave to be rectified as input and generates a DC component. The even-order short-circuit means 301 to 304 include a plurality of line members, such as line members 311 to 314. Each of the line members included in the even-order short-circuit means 301 to 304 is an even-order short-circuit member that smooths the output of the rectifier circuit 11 by having zero impedance (short circuit) in at least one of the even-order harmonics of the wave to be rectified. One end is connected to one of the diodes 201 to 204, and the other end is open. As a result, the rectifier 10 has a simple circuit configuration that does not require a capacitor as a smoothing element, and high conversion efficiency can be obtained while suppressing performance variations. Note that a capacitor may be connected to the output terminal of the rectifier 10.

[0040] Embodiment 2. Figure 11 shows an example configuration of a rectifier 20 according to Embodiment 2 of the present disclosure. Similar to the rectifier 10, the rectifier 20 comprises a rectifier circuit 11, input terminals 100 and 101, a plurality of even-order short-circuiting means 301 to 304, and an output terminal 500. Unlike the rectifier 10, the rectifier 20 has a transmission line 420 inserted between a connection point 511 included in the rectifier circuit 11 and a via 411. The transmission line 420 has an electrical length L1 of one-quarter wavelength with respect to the second harmonic of the rectified wave. By generating even-order short circuits by the even-order short-circuiting means 301 to 304, the rectifier 20 can prevent leakage of even-order harmonics to the output side and smooth the output.

[0041] Figure 12 illustrates the problems in the rectifier 10. In the rectifier 10 of Embodiment 1 shown in Figure 8, the effect of even-order short circuits may be reduced if there are variations in the circuit board wiring pattern. In the rectifier 10, connection point 511 is connected to ground GND via via 411. The transmission line passing through via 411 can be replaced by an equivalent circuit EC1 including an inductor Le1. Therefore, connection point 511 is equivalently represented by a circuit loaded with inductor Le1.

[0042] The line member 312 in the even-order short-circuit means 302 and the line member 314 in the even-order short-circuit means 304 have an electrical length L1 of one-quarter wavelength with respect to the second harmonic of the rectified wave. However, due to variations in the substrate wiring pattern, it is assumed that the electrical lengths of the line members 312 and 314 will be shorter than one-quarter wavelength of the second harmonic. In this assumption, the line member 312 can be replaced by an equivalent circuit EC2 including a capacitor Ce1, and the line member 314 can be replaced by an equivalent circuit EC3 including a capacitor Ce2. Therefore, the line member 312 is equivalently represented as a circuit loaded with a capacitor Ce1, and the line member 314 is equivalently represented as a circuit loaded with a capacitor Ce2.

[0043] In equivalent circuits EC1 to EC3, parallel resonance at the second harmonic may occur between inductor Le1 and capacitors Ce1 and Ce2. When this parallel resonance occurs, the combined impedance viewed from the connection point of the anodes of diode 202 and diode 204 becomes open (infinite) with respect to the second harmonic. Therefore, since line members 312 and 314 are equivalently considered unconnected, the effect of even-order short circuits is reduced.

[0044] The rectifier 20 shown in Figure 11 has a configuration in which a transmission line 420 is placed between the connection point 511 and the via 411. The transmission line 420 is connected to the ground side of the rectifier circuit 11 and is a ground-side transmission line member having an electrical length L1 of one-quarter wavelength with respect to the second harmonic of the rectified wave. In this configuration, the impedance on the via 411 side as seen from the connection point 511 is set to open in the second harmonic. Via 411 is equivalently unconnected with respect to the second harmonic. In other words, via 411 can be treated as not existing with respect to the second harmonic. Since the connection point 511 of the rectifier circuit 11 is not connected to via 411 in the second harmonic, the equivalent capacitor Ce1 of transmission line member 312 and the equivalent capacitor Ce2 of transmission line member 314 do not generate parallel resonance with the equivalent inductor Le1 of via 411 in the second harmonic. In this way, the rectifier 20 on which the transmission line 420 is arranged can prevent performance degradation due to variations in the circuit board wiring pattern.

[0045] Figure 13 shows another configuration example of the rectifier 20. The even-order short-circuiting means 301 to 304 in Figure 13 each include multiple open stubs corresponding to the even-order harmonics (2nd, 4th, 6th, etc.) of the wave being rectified. The rectifier 20 in Figure 13 has a different configuration from the rectifier 10 in Figure 9 due to the transmission line 420 placed between the connection point 511 and the via 411. Since the transmission line 420 has an electrical length L1 of one-quarter wavelength with respect to the 2nd harmonic of the wave being rectified, the connection point 511 of the rectifier circuit 11 is not connected to the via 411 in the 2nd harmonic. Therefore, the capacitors Ce1 and Ce2 of the line members 312 and 314 do not generate parallel resonance with the inductor Le1 of the via 411 in the 2nd harmonic.

[0046] Figure 14 shows yet another configuration example of the rectifier 20. The rectifier 20 in Figure 14 has a configuration in which a transmission line 421 is placed between the connection point 511 and the via 411. The transmission line 421 is a line member having an electrical length L2 of one-quarter wavelength for the fourth harmonic of the rectified wave. In this configuration, the impedance on the via 411 side as seen from the connection point 511 is set to open at the fourth harmonic. The connection point 511 of the rectifier circuit 11 is not connected to the via 411 at the fourth harmonic. Therefore, the equivalent capacitor of line member 322 and the equivalent capacitor of line member 324 do not generate parallel resonance with the equivalent inductor of via 411 at the fourth harmonic. Alternatively, the transmission line connected between the rectifier circuit 11 and the via 411 may have an electrical length of one-quarter wavelength for any even-order harmonic, so that the connection point 511 with the rectifier circuit 11 is not connected to the via 411 for any even-order harmonic.

[0047] Embodiment 3. Figure 15 shows an example configuration of a rectifier 30 according to Embodiment 3 of the present disclosure. Similar to the rectifier 10 in Figure 1, the rectifier 30 comprises a rectifier circuit 11, input terminals 100 and 101, a plurality of even-order short-circuiting means 301 to 304, and an output terminal 500. Unlike the rectifier 10 in Figure 1, the rectifier 30 has a capacitor 600 connected between connection point 510 and connection point 511 included in the rectifier circuit 11. The connection point 510 shown in Figure 15 is connected to the output terminal 500 via a transmission line 410. The connection point 511 shown in Figure 15 is grounded by being connected to the ground GND on the back of the substrate via a via 411. One end of the capacitor 600 is connected to connection point 510 on the output side of the rectifier circuit 11, and the other end is connected to connection point 511 on the ground side of the rectifier circuit 11. Thus, the rectifier 30 in Figure 15 includes a capacitor 600, one end of which is connected to the output side of the rectifier circuit 11, and the other end of which is connected to the ground side of the rectifier circuit 11.

[0048] Figure 16 shows another configuration example of the rectifier 30. In Figure 16, the rectifier circuit 11 included in the rectifier 30 is connected to the output terminal 501 via the transmission line 412 from the connection point 511, similar to the rectifier 10 in Figure 10. The output terminals 500 and 501 are DC output terminals that output DC differentially. Unlike the rectifier 10 in Figure 10, the rectifier 30 has a capacitor 600 connected between the connection point 510 included in the rectifier circuit 11 and the connection point 511. The connection point 510 shown in Figure 16 is connected to the output terminal 500 via the transmission line 410. The connection point 511 shown in Figure 16 is connected to the output terminal 501 via the transmission line 412. On the output side of the rectifier circuit 11, one end of the capacitor 600 is connected to the connection point 510 corresponding to one side of the differential output, and the other end is connected to the connection point 511 corresponding to the other side of the differential output. Thus, the rectifier 30 in Figure 16 includes a capacitor 600, one end of which is connected to one side of the differential output and the other end of which is connected to the other side of the differential output.

[0049] In the configurations shown in Figures 15 and 16, the capacitor 600 prevents low-frequency noise, which is noise with a frequency lower than the fundamental wave that flows into the rectifier 30, from leaking to the output side. As a result, the rectifier 30 can suppress the noise contained in the output. The capacitance value of the capacitor 600 can be determined to any value so as to suppress the leakage of low-frequency noise. The capacitance value of the capacitor 600 should be determined based on the radio wave environment in which the rectifier 30 is installed.

[0050] In the rectifier 30, the even-order short-circuiting means 301 to 304 prevent the leakage of even-order harmonics to the output side by generating even-order short circuits, thereby enabling output smoothing. The capacitor 600 is for suppressing low-frequency noise, and its purpose differs from that of smoothing capacitors included in conventional rectifiers. The rectifier 30 can achieve high efficiency in RF-DC conversion through harmonic processing and smoothing in the even-order short-circuiting means 301 to 304. In addition, the rectifier circuit 30 can achieve improved immunity to low-frequency noise with the help of the capacitor 600.

[0051] In the configurations shown in Figures 11, 13, and 14, a capacitor 600 may be connected between connection point 510 and connection point 511. In the rectifiers 20 of Figures 11 and 13, a transmission line 420 is inserted between connection point 511, which is included in the rectifier circuit 11, and via 411. The transmission line 420 has an electrical length L1 of one-quarter wavelength with respect to the second harmonic of the rectified wave. In the rectifiers 20 of Figure 14, a transmission line 421 is inserted between connection point 511 and via 411. The transmission line 421 has an electrical length L2 of one-quarter wavelength with respect to the fourth harmonic of the rectified wave. In these cases as well, the capacitor 600 is for suppressing low-frequency noise and has a different purpose than the smoothing capacitor included in conventional rectifiers. The rectifier 20 shown in Figures 11, 13, and 14 achieves high efficiency in RF-DC conversion through harmonic processing and smoothing in even-order short-circuit means 301-304. The transmission lines 420 and 421 prevent parallel resonance in harmonics, thus preventing performance degradation due to variations in the circuit board wiring pattern. Furthermore, the rectifier 20 with the added capacitor 600 achieves improved immunity to low-frequency noise.

[0052] This disclosure allows for various embodiments and modifications without departing from the broad spirit and scope of the technical idea. Furthermore, the embodiments described above are for illustrative purposes only and do not limit the scope of this disclosure. In other words, the scope of this disclosure is indicated by the claims, not by the embodiments. Various modifications made within the scope of the claims and the equivalent meaning of the technical idea are considered to be within the scope of this disclosure.

[0053] This application is based on Japanese Patent Application No. 2023-070750, filed on 24 April 2023. The entire specification, claims, and drawings of Japanese Patent Application No. 2023-070750 are incorporated herein by reference. [Explanation of Symbols]

[0054] 10, 20, 30 Rectifiers, 11 Rectifier circuits, 100, 101 Input terminals, 201-204 Diodes, 301-304 Even-order short-circuiting means, 311-314, 321-324, 331-334 Line components, 401-404, 410, 412, 420, 421 Transmission lines, 411 Vias, 500, 501 Output terminals, 510, 511 Connection points, 600 Capacitors

Claims

1. A rectifier circuit, which is composed of multiple diodes and generates a DC component when a wave to be rectified is input, The rectifier circuit comprises a plurality of line members connected to the rectifier circuit, The aforementioned plurality of diodes A first diode whose anode is connected to the input side of the rectifier circuit and whose cathode is connected to the output side of the rectifier circuit, A second diode whose cathode is connected to the input side of the rectifier circuit and whose anode is connected to the output side of the rectifier circuit, A third diode, whose anode is connected to the input side of the rectifier circuit and whose cathode is connected to the output side of the rectifier circuit, A fourth diode is included, the cathode of which is connected to the input side of the rectifier circuit and the anode of which is connected to the output side of the rectifier circuit. The aforementioned plurality of track members are Each of these is an even-order short-circuit member that smooths the output of the rectifier circuit by making the impedance zero in at least one of the even-order harmonics of the rectified wave. A first member having one end connected to the cathode of the first diode and the other end open, A second member having one end connected to the anode of the second diode and the other end open, A third member having one end connected to the cathode of the third diode and the other end open, A fourth member having one end connected to the anode of the fourth diode and the other end open, rectifier.

2. The output side of the rectifier circuit is provided with an output terminal that outputs single-phase DC, The rectifier according to claim 1.

3. The ground side of the rectifier circuit is grounded via a via. The rectifier according to claim 2.

4. The rectifier circuit is provided with a ground-side line member positioned between the ground side and the via, The grounding line member has an electrical length of one-quarter wavelength with respect to any even-order harmonic of the rectified wave, and the connection point of the rectifier circuit is not connected to the via in respect to any even-order harmonic of the rectified wave. The rectifier according to claim 3.

5. A capacitor is provided, with one end connected to the output side of the rectifier circuit and the other end connected to the ground side of the rectifier circuit. The rectifier according to claim 1.

6. The output side of the rectifier circuit is provided with an output terminal that outputs DC differentially, The rectifier according to claim 1.

7. A capacitor is provided, with one end connected to one side of the differential output and the other end connected to the other side of the differential output. The rectifier according to claim 6.

8. Each of the aforementioned line members is an open stub having an electrical length of one-quarter wavelength with respect to the second harmonic of the wave being rectified. A rectifier according to any one of claims 1 to 7.

9. Each of the aforementioned line members is a plurality of open stubs, each having an electrical length of one-quarter wavelength for each of the plurality of even-order harmonics of the wave being rectified. A rectifier according to any one of claims 1 to 7.

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