Compact wide-power rectification circuit based on matched filter network and adaptive power selection

Abstract

The invention discloses a compact wide-power rectification circuit based on a matched filter network and adaptive power selection. The compact wide-power rectification circuit comprises a first impedance matching microstrip line, the matched filter network, a low-power impedance compensation branch and a high-power impedance compensation branch. The matched filter network suppresses fundamental wave and second harmonic components of the radio frequency signal output by the first impedance matching microstrip line, and participates in impedance matching at the same time. The low-power impedance compensation branch and the high-power impedance compensation branch have a first impedance compensation value and a second impedance compensation value respectively, the first impedance compensation value is smaller than the second impedance compensation value, and the low-power impedance compensation branch, the high-power impedance compensation branch and the matched filter network are connected to the output end of the first impedance matching microstrip line in parallel. Stable working efficiency can be kept in a wide power range, the applicable power range is widened, the matched filter network is beneficial to reduction of the circuit size, and the compact design of the circuit is achieved. The method is widely applied to the technical field of wireless energy transmission.

Description

Technical Field

[0001] This invention relates to the field of wireless power transfer technology, and in particular to a compact wide-power rectifier circuit based on a matched filter network and adaptive power selection. Background Technology

[0002] With the rapid development of IoT technology in recent years, low-power sensor nodes, wearable devices, and smart terminals are widely used in environmental monitoring, healthcare, and smart cities. However, the power supply of these devices remains one of the core challenges restricting their large-scale deployment. Traditional battery power supply suffers from high maintenance costs, limited lifespan, and environmental pollution. Wireless power transfer technology, on the other hand, receives radio frequency signals of a certain frequency from the transmitter and converts them into DC power using a rectifier circuit, providing a sustainable green energy solution for IoT devices. In this technology, the Schottky diode, a core component of the rectifier circuit, exhibits a non-linear current-voltage characteristic. Therefore, as the frequency and power of the input signal change, the impedance of the Schottky diode changes significantly, easily causing impedance mismatch and resulting in a decrease in rectification efficiency. In practical applications of wireless power transfer, there is often a need for a transmitter to wirelessly transfer power to multiple nodes within a certain range. For different nodes, the received electromagnetic wave energy level will vary significantly due to free space loss and multipath effects along the transmission path from the transmitter to the receiver. For the same mobile node, the received signal power will also differ due to changes in the transmission distance caused by changes in relative position. The various unknown factors in these practical application scenarios can cause nonlinear changes in diode impedance, reducing the circuit's rectification efficiency and significantly degrading the performance of the entire wireless power transfer system. Therefore, a rectifier circuit with a wide power range is essential to adapt to more complex real-world scenarios. Furthermore, as IoT terminal nodes become increasingly miniaturized, achieving a compact circuit design while expanding the power range is particularly important.

[0003] Current rectifier designs for wireless power transfer struggle to balance adaptability to a wide input power range, structural complexity, and compact size, making it particularly difficult to meet the combined demands of IoT terminal nodes for miniaturization, low cost, and high efficiency. Summary of the Invention

[0004] To address the technical problems of current wireless power transfer technologies, such as large circuit size, high additional losses, non-concentrated energy output, and narrow power range, the present invention aims to provide a compact wide-power rectifier circuit based on a matched filter network and adaptive power selection.

[0005] Embodiments of the present invention include a compact wide-power rectifier circuit based on a matched filter network and adaptive power selection, the compact wide-power rectifier circuit based on a matched filter network and adaptive power selection comprising: The first impedance matching microstrip line is used to receive radio frequency signals and perform impedance matching on the radio frequency signals. Matched filter network; the matched filter network is used to suppress the fundamental and second harmonic components of the radio frequency signal output by the first impedance-matched microstrip line, and participates in impedance matching. The output terminal of the matched filter network is connected to the load. A low-power impedance compensation branch; the low-power impedance compensation branch has a first impedance compensation value; A high-power impedance compensation branch; the low-power impedance compensation branch, the high-power impedance compensation branch, and the matching filter network are connected in parallel to the output of the first impedance-matched microstrip line; the high-power impedance compensation branch has a second impedance compensation value; at the operating frequency, the first impedance compensation value is less than the second impedance compensation value.

[0006] Furthermore, the compact wide-power rectifier circuit based on matched filter network and adaptive power selection also includes: A DC blocking capacitor; the input terminal of the DC blocking capacitor is connected to the output terminal of the first impedance matching microstrip line, and the output terminal of the DC blocking capacitor is connected to the parallel connection terminal of the matching filter network, the low-power impedance compensation branch and the high-power impedance compensation branch.

[0007] Furthermore, the matched filter network includes a second impedance-matching microstrip line and a cross-linked coupling line; The input terminal of the second impedance matching microstrip line serves as the input terminal of the matched filter network and is connected to the output terminal of the DC blocking capacitor. The output of the second impedance-matching microstrip line is connected to the input of the cross-linked coupling line; The output of the cross-linked coupling line serves as the output of the matched filter network and is connected to the load.

[0008] Furthermore, the low-power impedance compensation branch includes a first diode and a first grounded microstrip line; The cathode of the first diode is connected to the output terminal of the DC blocking capacitor; The positive terminal of the first diode is connected to one end of the first grounded microstrip line; The other end of the first grounded microstrip line is grounded.

[0009] Furthermore, the high-power impedance compensation branch includes a second diode, a first impedance compensation microstrip line, and a second impedance compensation microstrip line. The cathode of the second diode is connected to the output terminal of the DC blocking capacitor; The positive terminal of the second diode is connected to one end of the first impedance-compensating microstrip line; The other end of the first impedance-compensating microstrip line is connected to a section of the second impedance-compensating microstrip line. The other end of the second impedance-compensated microstrip line is grounded.

[0010] Furthermore, the first diode and the second diode are Schottky diodes of the same type.

[0011] Furthermore, the compact wide-power rectifier circuit based on matched filter network and adaptive power selection also includes: Radio frequency (RF) source; the output terminal of the RF source is connected to the input terminal of the first impedance-matched microstrip line, and the RF source is used to output the RF signal.

[0012] Furthermore, the compact wide-power rectifier circuit based on matched filter network and adaptive power selection also includes: The dielectric substrate; the first impedance matching microstrip line, the matching filter network, the low-power impedance compensation branch and the high-power impedance compensation branch are all fixed on one side of the dielectric substrate by printed circuit technology.

[0013] Furthermore, the compact wide-power rectifier circuit based on matched filter network and adaptive power selection also includes: Floor; the floor is fixed to the other side of the dielectric substrate by a printed circuit process; the dielectric substrate is provided with metallized vias, the metallized vias penetrate both sides of the dielectric substrate, one end of the metallized vias is connected to a ground terminal on one side of the dielectric substrate, and the other end of the metallized vias is connected to the floor.

[0014] Furthermore, the dielectric substrate is made of Rogers R4003C, the thickness of the dielectric substrate is 0.813 mm, and the dielectric constant of the dielectric substrate is 3.38.

[0015] The beneficial effects of the embodiments of the present invention are as follows: The compact wide-power rectifier circuit based on matched filter network and adaptive power selection in the embodiments can compensate for the capacitive impedance generated by the diodes in the high-power impedance compensation branch and the low-power impedance compensation branch, and adjust the ratio of the input impedance magnitudes of the two branches to dynamically change under different input power conditions; when the input power is low, the ratio of the input impedance magnitudes of the high-power impedance compensation branch and the low-power impedance compensation branch is large, so most of the input power flows to the low-power impedance compensation branch; when the input power is high, the ratio of the input impedance magnitudes of the high-power impedance compensation branch and the low-power impedance compensation branch gradually decreases to approximately one, so the input power is concentrated in the low-power impedance compensation branch. The input power flows evenly to the low-power impedance compensation branch and the high-power impedance compensation rectification branch. The high-power impedance compensation branch and the low-power impedance compensation branch can work together, enabling the compact wide-power rectifier circuit to maintain stable operating efficiency over a wide power range. Because the compact wide-power rectifier can adaptively select the power distribution ratio of the signal according to the power variation of the input RF signal, it distributes the signal to the high-power impedance compensation branch and the low-power impedance compensation branch, thereby widening the applicable power range. The matched filter network, combined with the functions of the input impedance matching network and the harmonic suppression network, participates in impedance matching while suppressing the fundamental and second harmonic components of the RF signal, which helps to reduce the circuit size and achieve a compact circuit design. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the circuit principle structure of a compact wide-power rectifier circuit based on a matched filter network and adaptive power selection in the embodiment. Figure 2 is a schematic diagram of the circuit structure of the matched filter network and the compact wide-power rectifier circuit with adaptive power selection in the embodiment; Figure 3 The following is a simulation curve showing the suppression effect of the matched filter network on signals of various frequencies in the embodiment; Figure 4 The Smith chart shows the impedance matching simulation of the rectifier implemented by the matched filter network and the first impedance matching microstrip line in the embodiment. Figure 5 The following is a simulation curve of the input impedance magnitude of the low-power impedance compensation branch and the high-power impedance compensation branch in the embodiment. Figure 6 The figure shows the simulation curves of the input signal power distribution ratio between the low-power impedance compensation branch and the high-power impedance compensation branch in the embodiment. Figure 7 The figure shows the simulation results of the frequency response of the compact wide-power rectifier circuit in the embodiment when the input power is 6, 10 and 14 dBm respectively; Figure 8 The figure shows the measured results of the frequency response of the compact wide-power rectifier circuit in the embodiment when the input power is 6, 10 and 14 dBm respectively; Figure 9 The figure shows the simulation and measured results of the rectification efficiency as a function of the input signal frequency for the compact wide-power rectifier circuit in the embodiment when the input power is 15, 20 and 25 dBm respectively. Figure 10 The figure shows the simulation and measured results of the rectification efficiency as a function of the input signal power for the compact wide-power rectifier circuit in the embodiment, when the input frequencies are 2.4 GHz and 2.45 GHz, respectively. Detailed Implementation

[0017] To address the issue of a narrow power range, the following methods can be considered: The first method involves designing an impedance compression network for the diodes to reduce the impedance variation range under different power levels, thereby improving impedance matching and expanding the circuit's input power range. However, this method only allows the circuit to have an even number of branches, and each branch needs to be identical. When each branch operates at different power levels to adapt to different application scenarios, impedance compression technology becomes unsuitable. The second method involves introducing a power control unit, using field-effect transistors to switch the circuit's operating state, or using couplers, power dividers, circulators, or adaptive power distribution networks to distribute the input signal power to various rectifier branches operating under different input power conditions. This allows low-for-voltage diodes to operate under low input power conditions, and high-for-voltage diodes to operate under high input power levels, thus widening the rectifier's operating power range. The third method is based on time-domain inversion theory, using GaN transistors to design rectifier circuits and widening the power range by selecting appropriate conduction angles for the transistors.

[0018] The methods described above can effectively broaden the power range of rectifiers, but they often require multiple independent sub-rectifiers. These sub-rectifiers need independent impedance matching networks, harmonic suppression networks, and loads. Such circuits suffer from problems such as insufficient concentration of rectified energy output, complex circuit structure, and size severely limited by impedance matching and harmonic suppression networks.

[0019] To address the issue of excessively large circuit size, alternative solutions include using coupled transmission lines as matching networks, employing lumped elements for impedance matching and harmonic suppression networks, utilizing the inherent frequency selectivity of transistors to omit matching networks, and using curved microstrip lines to achieve a more compact circuit layout. However, the compact rectifiers designed using these techniques cannot maintain stable operation under wide input power conditions.

[0020] Based on the above principles, this embodiment provides a compact wide-power rectifier circuit based on a matched filter network and adaptive power selection. The structure of the compact wide-power rectifier circuit based on a matched filter network and adaptive power selection is as follows: Figure 1 As shown in Figure 2, Figure 1 Figure 2 is a schematic diagram of the circuit principle structure. Part (a) of Figure 2 is a schematic diagram of the actual circuit structure, and part (b) of Figure 2 is a schematic diagram of the line width and other dimensional parameters of each component. Figure 2 shows the layout from the side of the dielectric substrate where each component has been fabricated. The positions of each component in Figure 2 are shown in the diagram. Figure 1 The corresponding characters are the same.

[0021] Reference Figure 1 As shown in Figure 2, the compact wide-power rectifier circuit based on a matched filter network and adaptive power selection includes components such as a first impedance-matching microstrip line, a matched filter network, a low-power impedance compensation branch, and a high-power impedance compensation branch. Through the matched filter network, the high-power impedance compensation branch, and the low-power impedance compensation branch, the compact wide-power rectifier circuit based on a matched filter network and adaptive power selection can achieve its basic functions. Further optimization can be achieved by adding components, such as using a DC blocking capacitor to block the DC signal from the radio frequency signal.

[0022] In this embodiment, the components of the compact wide-power rectifier circuit based on the matched filter network and adaptive power selection can be fabricated on a dielectric substrate using printed circuit board (PCB) technology. Rogers R4003C material with a thickness of 0.813 mm and a dielectric constant of 3.38 can be used as the dielectric substrate. On one side of the dielectric substrate, components such as the matched filter network, high-power impedance compensation branch, low-power impedance compensation branch, first impedance matching microstrip line, resistors, RF sources, and DC blocking capacitors are fabricated. On the other side of the dielectric substrate, a ground plane is fabricated as the ground line for the compact wide-power rectifier circuit based on the matched filter network and adaptive power selection. Each component can be connected to the ground plane on the other side of the dielectric substrate through metallized vias penetrating the substrate, thereby achieving grounding of the components in the compact wide-power rectifier circuit based on the matched filter network and adaptive power selection.

[0023] In this embodiment, the radio frequency (RF) source can be part of a compact wide-power rectifier circuit based on a matched filter network and adaptive power selection. In this case, the RF source can be a physical device or a component outside the compact wide-power rectifier circuit based on a matched filter network and adaptive power selection, such as an energy source for wireless power transmission. In this case, the RF source may not correspond to a specific physical device. The RF source can output an RF signal with a specific frequency, such as the operating frequency in this embodiment. In this embodiment, the operating frequency, i.e., the frequency of the RF signal output by the RF source, is 2.4 GHz.

[0024] Reference Figure 1 The input terminal of the first impedance matching microstrip line is connected to the output terminal of the RF source, and the RF signal output by the RF source can enter the first impedance matching microstrip line 1. A DC blocking capacitor can be set between the output terminal of the first impedance matching microstrip line and the parallel input terminals of the matching filter network, the low-power impedance compensation rectifier branch, and the high-power impedance compensation rectifier branch, thereby isolating the DC signal output by the RF source.

[0025] In this embodiment, the first impedance matching microstrip line serves as an impedance matching line.

[0026] In this embodiment, refer to Figure 1 The input terminals of the matched filter network, the low-power impedance compensation branch, and the high-power impedance compensation branch are connected in parallel to form a parallel connection terminal. This parallel connection terminal can be directly connected to the output terminal of the first impedance matching microstrip line, or it can be connected to the output terminal of the first impedance matching microstrip line through a DC blocking capacitor. That is, the output terminal of the first impedance matching microstrip line is connected to the input terminal of the DC blocking capacitor, and the output terminal of the DC blocking capacitor is connected to the parallel connection terminal.

[0027] By setting a DC blocking capacitor, the RF signal output from the first impedance-matched microstrip line can be rectified.

[0028] In this embodiment, refer to Figure 1 As shown in Figure 2, the low-power impedance compensation branch includes a first diode and a first grounded microstrip line. The cathode of the first diode serves as the input terminal of the low-power impedance compensation branch and is connected to the output terminal of the DC blocking capacitor. The anode of the first diode is connected to one end of the first grounded microstrip line, and the other end of the first grounded microstrip line serves as the output terminal of the low-power impedance compensation branch and is grounded.

[0029] In this embodiment, the first grounded microstrip line is essentially a short-circuit transmission line resonant branch, and its equivalent input impedance is: Z in=jZ0tan(βl), where Z0 represents the characteristic impedance of the first grounded microstrip line, β represents the propagation constant, l is the actual length of the first grounded microstrip line, and βl represents the electrical length of the first grounded microstrip line. By adjusting the appropriate electrical length of the first grounded microstrip line, at a power point in the lower power range at the operating frequency (2.45GHz), the capacitive impedance of the first diode in the low-power impedance compensation branch can be compensated to 0. Although there is a small imaginary impedance margin in the vicinity of this region, the input impedance magnitude of this branch can be controlled to be small in the low-power range, and the increase is mostly due to the change of the real impedance of the diode with the input power, and the growth rate is slow. Therefore, the impedance and electrical length of the first grounded microstrip line directly affect the magnitude of the capacitive impedance compensated by the low-impedance compensation branch and the rate at which the input impedance of the low-impedance compensation branch 103 changes with the input power.

[0030] In this embodiment, refer to Figure 1 As shown in Figure 2, the high-power impedance compensation branch includes a second diode, a first impedance compensation microstrip line, and a second impedance compensation microstrip line. The negative terminal of the second diode serves as the input terminal of the high-power impedance compensation branch, connected to the output terminal of the DC blocking capacitor. The positive terminal of the second diode is connected to one end of the first impedance compensation microstrip line, and the other end of the first impedance compensation microstrip line is connected to one end of the second impedance compensation microstrip line. The other end of the second impedance compensation microstrip line serves as the output terminal of the high-power impedance compensation branch, grounded. Similar to the principle of the low-power impedance compensation branch, in the high-power impedance compensation branch, the first and second impedance compensation microstrip lines compensate for the capacitive reactance of the second diode within a higher power range, reducing its capacitance. Since the real impedance of the second diode increases with increasing input power, the input impedance magnitude of the high-power impedance compensation branch decreases and becomes more stable. Therefore, the impedance and electrical length of the first and second impedance compensation microstrip lines directly affect the magnitude of the capacitive impedance compensated by the high-impedance compensation branch and the rate at which the input impedance magnitude of the high-impedance compensation branch changes with input power.

[0031] In this embodiment, both the first diode and the second diode are Schottky diodes, and both are model HSMS2822.

[0032] In this embodiment, the compact wide-power rectifier circuit based on the matched filter network and adaptive power selection can be used for a specific operating frequency, such as an operating frequency of 2.4 GHz.

[0033] In this embodiment, the first grounding microstrip line is fabricated as a low-power impedance compensation branch with a first impedance compensation value, and the first impedance compensation microstrip line and the second impedance compensation microstrip line are fabricated as high-power impedance compensation branches with a second impedance compensation value. At at least one frequency point of the operating frequency (e.g., 2.4 GHz), the first impedance compensation value is less than the second impedance compensation value. That is, at a specific operating frequency, the high-power impedance compensation branch can introduce a larger impedance compensation value, and the low-power impedance compensation branch can introduce a smaller impedance compensation value.

[0034] In this embodiment, the compact wide-power rectifier circuit based on a matched filter network and adaptive power selection includes a matched filter network and a load. (Refer to...) Figure 1 As shown in Figure 2, the input of the matched filter network is connected to the output of the DC blocking capacitor, and the output of the matched filter network 101 is used for load connection.

[0035] Refer to Figure 2 and Figure 3 The matched filter network consists of a cross-toe coupling line and a second impedance matching microstrip line. By adjusting the physical parameters of the cross-toe coupling line of the matched filter network, the fundamental frequency (2.4 GHz) and the second harmonic frequency (4.8 GHz) of the operating frequency can be suppressed.

[0036] In this embodiment, different components can be connected not only directly but also via microstrip lines. For example, referring to Figure 2, the first impedance compensation microstrip line is connected to the DC blocking capacitor, and the cross-linked coupling line is connected to the load via microstrip lines. These microstrip line structures can be routed along an arc trajectory, thereby saving space and improving the compactness of the rectifier circuit. Similarly, components such as the first grounding microstrip line can also be routed along an arc trajectory, further improving the compactness of the rectifier circuit.

[0037] Reference Figure 4 The impedance of the matched filter network directly affects the input impedance of the compact wide-power rectifier circuit based on the matched filter network and adaptive power selection. By adjusting the parameters of the second impedance matching microstrip line, the input impedance of the compact wide-power rectifier circuit based on the matched filter network and adaptive power selection is brought close to the real impedance. Then, impedance matching close to 50Ω can be achieved using the first impedance matching microstrip line. The matched filter network combines the matching network and harmonic suppression network in the traditional rectifier circuit topology, occupying less circuit area and achieving a compact circuit design.

[0038] In this embodiment, the working principle of the compact wide-power rectifier circuit based on the matched filter network and adaptive power selection is as follows: In the low-power impedance compensation branch, the first grounded microstrip line can compensate for the capacitive impedance generated by the first diode, adjusting the rate at which the overall input impedance magnitude of the low-power impedance compensation branch changes with the input power; similarly, in the high-power impedance compensation branch, the first impedance compensation microstrip line and the second impedance compensation microstrip line can compensate for the capacitive impedance generated by the second diode, adjusting the rate at which the overall input impedance magnitude of the high-power impedance compensation branch changes with the input power; since the specific structures of the low-power impedance compensation branch and the high-power impedance compensation branch are different, the impedance compensation values ​​introduced by the low-power impedance compensation branch and the high-power impedance compensation branch are different. Therefore, the change of the input impedance magnitude of the low-power impedance compensation branch with the input power is also different from that of the high-power impedance compensation branch. The differences between them are as follows: Figure 5 As shown; since the low-power impedance compensation branch and the high-power impedance compensation branch are connected in parallel, the RF signal output from the first impedance-matched microstrip line may flow to either the low-power impedance compensation branch or the high-power impedance compensation branch. Let the power of the RF signal output from the first impedance-matched microstrip line be... P in The power flowing to the low-power impedance compensation branch is P in103 The power flowing to the high power impedance compensation branch is P in104 So there are P in = P in103 + P in104 P in103 / P in104 = |Z in104 | / |Z in103 | in Z in104 The overall input impedance after compensation by the second impedance compensation value for the high-power impedance compensation branch. Z in103 The input impedance is the overall impedance after compensation by the low-power impedance compensation branch using the first impedance compensation value. The difference between the low-power impedance compensation branch and the high-power impedance compensation branch will cause the input impedance ratio of the high-power impedance compensation branch to the low-power impedance compensation branch to be higher when the power of the RF signal output from the first impedance-matched microstrip line is low (e.g., below a power threshold). |Z in104| / |Z in103 The larger the impedance, the higher the output power of the first impedance-matched microstrip line. P in Most of the power is concentrated in the low-power impedance compensation branch. When the input power is high (e.g., above the power threshold), the input impedance ratio between the high-power impedance compensation branch and the low-power impedance compensation branch is... |Z in104 | / |Z in103 The impedance gradually decreases until it is approximately equal to 1, therefore the power output of the first impedance-matched microstrip line is... P in The power flows evenly to the low-power impedance compensation branch and the high-power impedance compensation rectifier branch. The input power distribution ratio between the low-power impedance compensation branch and the high-power impedance compensation branch changes with the input power as follows: Figure 6 As shown; therefore, this compact wide-power rectification can adaptively select the power distribution ratio of the signal according to the power variation of the input RF signal, distributing the signal to the low-power impedance compensation branch and the high-power impedance compensation branch, thereby widening the power range. That is, through the synergistic work of the low-power impedance compensation branch and the high-power impedance compensation branch, the compact wide-power rectification circuit can maintain an overall efficiency of more than 50% over a wide range of input power variations. On this basis, the fundamental and second harmonics of the RF signal are suppressed by the matched filter network, which also participates in impedance matching, improving the rectification effect and reducing the circuit size.

[0039] In this embodiment, the aforementioned power threshold is typically equal to the maximum input power that the first diode in the low-power impedance compensation branch can effectively rectify, for example, 25 dBm. That is, if the input power of the RF signal is lower than this power threshold, it falls within the low-power range described herein, and most of the input power flows to the low-power impedance compensation branch; as the input power increases to exceed this power threshold, it falls within the high-power range described herein, causing a decrease in the single-diode performance of the first diode in the low-power impedance compensation branch, while the high-power impedance compensation branch can divert the excess power, thereby co-rectifying with the low-power impedance compensation branch.

[0040] In this embodiment, the compact wide-power rectifier circuit based on a matched filter network and adaptive power selection can be fabricated through the following steps: Step S1: Select a suitable diode based on the application of the circuit and the required frequency and power range; Step S2: Design different high and low power impedance compensation branches and matching filter networks according to the expected power range and operating frequency; Step S3: Connect the impedance compensation branches, matching filter networks, loads and first impedance matching microstrip lines operating at different power levels, wherein each impedance compensation branch and matching filter network is connected in parallel. Step S4: Fine-tune some parameters of the circuit to achieve better impedance matching and efficiency.

[0041] The simulation curves for return loss of a compact wide-power rectifier circuit based on a matched filter network and adaptive power selection, with input power of 6, 10, and 14 dBm, as a function of frequency are shown below. Figure 7 As shown. By Figure 7 It can be seen that when the input power is 6, 10, and 14 dBm, this rectifier circuit achieves good matching around 2.5 GHz. When the input power is 14 dBm, the return loss is less than -10 dB in the range of 2.36 GHz to 2.84 GHz, and less than -20 dB in the range of 2.4 GHz to 2.5 GHz, achieving good impedance matching in this frequency range.

[0042] Figure 8 This figure shows the measured return loss of the compact wide-power rectifier circuit based on a matched filter network and adaptive power selection as a function of frequency when the input power is 6, 10, and 14 dBm. As can be seen from the figure, this rectifier circuit achieves good matching around 2.4 GHz when the input power is 6, 10, and 14 dBm. When the input power is 14 dBm, the return loss is below -10 dB in the range of 2.32 GHz to 2.87 GHz and below -15 dB in the range of 2.35 GHz to 2.43 GHz, achieving good impedance matching within this frequency range.

[0043] Figure 9 The graphs show the simulation and measured results of the rectification efficiency of this circuit as a function of the input signal frequency when the input power is 15, 20, and 25 dBm. The rectifier achieves a maximum measured rectification efficiency of 68% at an input signal frequency of 2.4 GHz. When the input power is 25 dBm, the rectification efficiency is greater than 40% from 2.34 GHz to 3.1 GHz. There are some discrepancies between the actual test results and the simulation results, mainly due to errors in circuit fabrication precision and inaccuracies in the diode simulation model.

[0044] Figure 10The figures show the simulation and measured results of the rectification efficiency of the circuit as a function of input signal power at input frequencies of 2.4 GHz and 2.45 GHz. At an input frequency of 2.4 GHz, the actual measured rectification efficiency reaches a maximum of 68% at a power value of 25 dBm. At an input frequency of 2.4 GHz, the rectification efficiency greater than 50% ranges from 8.5 dBm to 31.5 dBm (power range of 23 dB). At an input frequency of 2.4 GHz, the rectification efficiency greater than 40% ranges from 7 dBm to 31.5 dBm (power range of 24.5 dB). There are some deviations between the actual test results and the simulation results, mainly due to errors in circuit fabrication precision and inaccuracies in the diode simulation model. The above results demonstrate the accuracy and feasibility of the design theory of this invention.

[0045] In summary, this invention proposes a compact wide-power rectifier circuit based on a matched filter network and adaptive power selection. This circuit achieves high- and low-power impedance compensation branches and a matched filter network, connected in parallel, thus realizing efficient rectification over a wide power range while maintaining a compact design. Specifically, the compact wide-power rectifier circuit based on the matched filter network and adaptive power selection includes high-power impedance compensation branches and low-power impedance compensation branches. These branches compensate for the capacitive impedance generated by the diodes within their respective branches and adjust the rate at which the input impedance of each branch changes with the input power. When the input power is low, most of the input power flows to the low-power impedance compensation branch. When the input power is high, the input power flows to the low-power impedance compensation branch and the high-power impedance compensation branch in a balanced proportion. The low-power impedance compensation branch and the high-power impedance compensation branch work together, ensuring that the overall compact wide-power rectifier circuit maintains its operating efficiency. The compact wide-power rectification adaptively selects the signal power allocation ratio according to changes in the input signal power level, guiding the input power to the low-power impedance compensation branch and the high-power impedance compensation branch according to the dynamic power allocation ratio, thereby widening the power range. This invention also incorporates a matched filter network, which, while suppressing the fundamental frequency (2.4 GHz) and second harmonic component (4.8 GHz) of the input signal, participates in the impedance matching of the rectifier, achieving a compact circuit design.

[0046] It should be noted that, unless otherwise specified, when a feature is referred to as "fixed" or "connected" to another feature, it can be directly fixed or connected to the other feature, or indirectly fixed or connected to the other feature. Furthermore, the descriptions of "upper," "lower," "left," and "right" used in this disclosure are only relative to the relative positional relationships of the components of this disclosure in the accompanying drawings. The singular forms "a" and "the" used in this disclosure are also intended to include the plural forms, unless the context clearly indicates otherwise. Moreover, unless otherwise defined, all technical and scientific terms used in this embodiment have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this embodiment specification is only for describing specific embodiments and is not intended to limit the embodiments of the invention. The term "and / or" as used in this embodiment includes any combination of one or more of the associated listed items.

[0047] It should be understood that although the terms first, second, third, etc., may be used to describe various elements in this disclosure, these elements should not be limited to these terms. These terms are only used to distinguish elements of the same type from each other. For example, a first element may also be referred to as a second element without departing from the scope of this disclosure, and similarly, a second element may also be referred to as a first element. The use of any and all instances or exemplary language (“e.g.,” “such as,” etc.) provided in this embodiment is intended only to better illustrate embodiments of the invention and, unless otherwise required, does not impose a limitation on the scope of embodiments of the invention.

[0048] It should be recognized that embodiments of the present invention can be implemented or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable storage medium. The method can be implemented using standard programming techniques—including a non-transitory computer-readable storage medium configured with a computer program, wherein such a storage medium causes the computer to operate in a specific and predefined manner—according to the methods and drawings described in the specific embodiments. Each program can be implemented in a high-level procedural or object-oriented programming language to communicate with the computer system. However, if desired, the program can be implemented in assembly or machine language. In any case, the language can be a compiled or interpreted language. Furthermore, for this purpose, the program can run on a programmed application-specific integrated circuit (ASIC).

[0049] Furthermore, the procedures described in this embodiment can be performed in any suitable order unless otherwise indicated by this embodiment or otherwise obviously contradict the context. The procedures (or variations and / or combinations thereof) described in this embodiment can be executed under the control of one or more computer systems configured with executable instructions, and can be implemented by hardware or a combination thereof as code (e.g., executable instructions, one or more computer programs, or one or more applications) that commonly executes on one or more processors. A computer program includes a plurality of instructions executable by one or more processors.

[0050] Furthermore, the method can be implemented in any suitable type of computing platform, including but not limited to personal computers, minicomputers, mainframes, workstations, networked or distributed computing environments, standalone or integrated computer platforms, or in communication with charged particle tools or other imaging devices, etc. Aspects of embodiments of the invention can be implemented as machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, optical read and / or write storage medium, RAM, ROM, etc., such that it is readable by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the processes described herein. Furthermore, the machine-readable code, or portions thereof, can be transmitted via wired or wireless networks. The invention of this embodiment includes these and other different types of non-transitory computer-readable storage media when such media comprises instructions or programs that implement the steps above in conjunction with a microprocessor or other data processor. Embodiments of the invention also include the computer itself when programmed according to the methods and techniques of embodiments of the invention.

[0051] A computer program can be applied to input data to perform the functions of this embodiment, thereby transforming the input data to generate output data stored in non-volatile memory. The output information can also be applied to one or more output devices, such as a display. In a preferred embodiment of the invention, the transformed data represents physical and tangible objects, including a specific visual depiction of physical and tangible objects generated on the display.

[0052] The above are merely preferred embodiments of the present invention. The embodiments of the present invention are not limited to the above-described implementations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the embodiments of the present invention, as long as they achieve the same technical effects, should be included within the scope of protection of the embodiments of the present invention. Within the scope of protection of the embodiments of the present invention, the technical solutions and / or implementation methods can have various modifications and variations.

Claims

1. A compact wide power rectifier circuit based on a matched filter network and adaptive power selection, characterized by, The compact wide power rectifier circuit based on the matching filter network and adaptive power selection comprises: a first impedance matching microstrip line, which is used to receive a radio frequency signal and perform impedance matching on the radio frequency signal; a matching filter network, which is used to suppress fundamental wave and second harmonic components of the radio frequency signal output by the first impedance matching microstrip line while participating in impedance matching, and has an output end connected to a load; a low-power impedance compensation branch, which has a first impedance compensation value; a high-power impedance compensation branch, which is connected in parallel to the output end of the first impedance matching microstrip line together with the matching filter network and the low-power impedance compensation branch, has a second impedance compensation value, and has the first impedance compensation value smaller than the second impedance compensation value at a working frequency.

2. A compact wide power rectifier circuit based on a matched filter network and adaptive power selection according to claim 1, characterized in that, The compact wide power rectifier circuit based on the matching filter network and adaptive power selection further comprises: a DC blocking capacitor, which has an input end connected to the output end of the first impedance matching microstrip line and an output end connected to the parallel connection end of the matching filter network, the low-power impedance compensation branch, and the high-power impedance compensation branch.

3. The compact wide power rectifier circuit based on the matching filter network and adaptive power selection according to claim 2, wherein: the matching filter network comprises a second impedance matching microstrip line and a stub coupling line; the input end of the second impedance matching microstrip line serves as the input end of the matching filter network and is connected to the output end of the DC blocking capacitor; the output end of the second impedance matching microstrip line is connected to the input end of the stub coupling line; the output end of the stub coupling line serves as the output end of the matching filter network and is connected to the load.

4. The compact wide power rectifier circuit based on the matching filter network and adaptive power selection according to claim 3, wherein: the low-power impedance compensation branch comprises a first diode and a first ground microstrip line; the negative electrode of the first diode is connected to the output end of the DC blocking capacitor; the positive electrode of the first diode is connected to one end of the first ground microstrip line; the other end of the first ground microstrip line is grounded.

5. The compact wide power rectifier circuit based on the matching filter network and adaptive power selection according to claim 4, wherein: the high-power impedance compensation branch comprises a second diode, a first impedance compensation microstrip line, and a second impedance compensation microstrip line; the negative electrode of the second diode is connected to the output end of the DC blocking capacitor; the positive electrode of the second diode is connected to one end of the first impedance compensation microstrip line; the other end of the first impedance compensation microstrip line is connected to one end of the second impedance compensation microstrip line; the other end of the second impedance compensation microstrip line is grounded.

6. The compact wide power rectifier circuit based on the matching filter network and adaptive power selection according to claim 5, wherein: the first diode and the second diode are Schottky diodes of the same type.

7. The compact wide power rectifier circuit based on a matched filter network and adaptive power selection of claim 5, wherein, The compact wide power rectifier circuit based on the matching filter network and adaptive power selection further comprises: A radio frequency source, an output end of the radio frequency source is connected with an input end of the first impedance matching microstrip line, and the radio frequency source is used to output the radio frequency signal.

8. A compact wide power rectifier circuit based on a matched filter network and adaptive power selection according to any of claims 1-7, characterized in that, The compact wide power rectifier circuit based on the matching filter network and adaptive power selection further comprises: A dielectric substrate, the first impedance matching microstrip line, the matching filter network, the low power impedance compensation branch and the high power impedance compensation branch are fixed on one side of the dielectric substrate through a printed circuit process.

9. A compact wide power rectifier circuit based on a matched filter network and adaptive power selection according to claim 8, characterized in that, The compact wide power rectifier circuit based on the matching filter network and adaptive power selection further comprises: A ground plate, the ground plate is fixed on the other side of the dielectric substrate through a printed circuit process, the dielectric substrate is provided with a metalized via, the metalized via penetrates through the two sides of the dielectric substrate, one end of the metalized via is connected with a ground end on one side of the dielectric substrate, and the other end of the metalized via is connected with the ground plate.

10. The compact wide power rectifier circuit based on the matching filter network and adaptive power selection according to claim 8, wherein: The material of the dielectric substrate is Rogers R4003C, the thickness of the dielectric substrate is 0.813 mm, and the dielectric constant of the dielectric substrate is 3.38.

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