A matched filter circuit and a radio frequency circuit

Abstract

The present application is applicable to the field of radio frequency technology, and provides a matched filter circuit and a radio frequency circuit, wherein the matched filter circuit includes a first filter circuit, a first matching circuit, a second filter circuit and a second matching circuit; the input end of the first filter circuit is connected to the first input and output end and the source end of the first matching circuit, and the output end of the first filter circuit is grounded; the second input and output end of the first matching circuit is connected to the input end of the second filter circuit and the first input and output end of the second matching circuit, and the first output end and the second output end of the first matching circuit are grounded; the output end of the second filter circuit is grounded; the second input and output end of the second matching circuit is connected to the load end, and the first output end and the second output end of the second matching circuit are grounded. The present application enables different source ends to use the same matched filter circuit, can solve the problem of spurious and radio frequency performance debugging, has low debugging difficulty, shortens the development cycle and improves the version update speed.

Description

Technical Field

[0001] The present application belongs to the field of radio frequency technology, and in particular relates to a matching filter circuit and a radio frequency circuit. Background Art

[0002] The RF circuits of communication systems generally require impedance matching to ensure effective reception and transmission of the system. For example, in the wireless communication system of the Industrial Internet of Things, there are strict requirements on the size of the transmission power, usually not higher than +20dBm. If good impedance matching cannot be achieved, it will affect the communication distance of the communication system. The most ideal situation for RF circuits is that the equivalent impedance of the source end, transmission line and load end is 50Ω. However, in the design process of RF circuits, different impedance matching circuits need to be designed for different source ends, and the problems of spurious signals and RF performance debugging need to be solved. The debugging is difficult, which prolongs the development cycle and reduces the speed of version updates. Summary of the invention

[0003] The embodiments of the present application provide a matching filter circuit and a radio frequency circuit to solve the problem that different impedance matching circuits need to be designed for different source ends during the design process of the radio frequency circuit, and to solve the problem of spurious and radio frequency performance debugging, which makes debugging difficult, prolongs the development cycle and reduces the speed of version updates.

[0004] A first aspect of an embodiment of the present application provides a matched filter circuit, including a first filter circuit, a first matching circuit, a second filter circuit, and a second matching circuit;

[0005] The input end of the first filter circuit is connected to the first input-output end and the source end of the first matching circuit, and the output end of the first filter circuit is grounded;

[0006] The second input and output end of the first matching circuit is connected to the input end of the second filter circuit and the first input and output end of the second matching circuit, and the first output end and the second output end of the first matching circuit are grounded;

[0007] The output terminal of the second filtering circuit is grounded;

[0008] The second input and output terminals of the second matching circuit are connected to the load terminal, and the first output terminal and the second output terminal of the second matching circuit are grounded.

[0009] In one embodiment, the first filter circuit includes a first inductor unit and a first capacitor unit;

[0010] The input end of the first inductor unit is the input end of the first filter circuit, and the output end of the first inductor unit is connected to the input end of the first capacitor unit;

[0011] The output end of the first capacitor unit is the output end of the first filter circuit.

[0012] In one embodiment, the first inductor unit includes a first inductor, and the first capacitor unit includes a first capacitor;

[0013] The input end and the output end of the first inductor are respectively the input end and the output end of the first inductor unit;

[0014] The input end and the output end of the first capacitor are respectively the input end and the output end of the first capacitor unit.

[0015] In one embodiment, the first matching circuit includes a second capacitor unit, a second inductor unit and a third capacitor unit;

[0016] The input end of the second capacitor unit and the first input and output end of the second inductor unit are connected to form the first input and output end of the first matching circuit, and the output end of the second capacitor unit is the first output end of the first matching circuit;

[0017] The second input-output end of the second inductor unit and the input end of the third capacitor unit are connected to form the second input-output end of the first matching circuit;

[0018] The output end of the third capacitor unit is the second output end of the first matching circuit.

[0019] In one embodiment, the second capacitor unit includes a second capacitor, the second inductor unit includes a second inductor, and the third capacitor unit includes a third capacitor;

[0020] The input end and the output end of the second capacitor are respectively the input end and the output end of the second capacitor unit;

[0021] The first input-output terminal and the second input-output terminal of the second inductor are respectively the first input-output terminal and the second input-output terminal of the second inductor unit;

[0022] The input end and the output end of the third capacitor are respectively the input end and the output end of the third capacitor unit.

[0023] In one embodiment, the second filtering circuit includes a third inductor unit and a fourth capacitor unit;

[0024] The input end of the third inductor unit is the input end of the second filter circuit, and the output end of the third inductor unit is connected to the input end of the fourth capacitor unit;

[0025] The output end of the fourth capacitor unit is the output end of the second filter circuit.

[0026] In one embodiment, the third inductor unit includes a third inductor, and the fourth capacitor unit includes a fourth capacitor;

[0027] The input end and the output end of the third inductor are respectively the input end and the output end of the third inductor unit;

[0028] The input end and the output end of the fourth capacitor are respectively the input end and the output end of the fourth capacitor unit.

[0029] In one embodiment, the second matching circuit includes a fifth capacitor unit, a fourth inductor unit and a sixth capacitor unit;

[0030] The input end of the fifth capacitor unit and the first input and output end of the fourth inductor unit are connected to form the first input and output end of the second matching circuit, and the output end of the fifth capacitor unit is the first output end of the second matching circuit;

[0031] The second input-output end of the fourth inductor unit and the input end of the sixth capacitor unit are connected to form the second input-output end of the second matching circuit;

[0032] The output end of the sixth capacitor unit is the second output end of the second matching circuit.

[0033] In one embodiment, the fifth capacitor unit includes a fifth capacitor, the fourth inductor unit includes a fourth inductor, and the sixth capacitor unit includes a sixth capacitor;

[0034] The input end and the output end of the fifth capacitor are respectively the input end and the output end of the fifth capacitor unit;

[0035] The first input-output terminal and the second input-output terminal of the fourth inductor are respectively the first input-output terminal and the second input-output terminal of the fourth inductor unit;

[0036] The input end and the output end of the sixth capacitor are respectively the input end and the output end of the sixth capacitor unit.

[0037] A second aspect of an embodiment of the present application provides a radio frequency circuit, including a source end, a load end, and the matching filter circuit provided by the first aspect of an embodiment of the present application.

[0038] The first aspect of the embodiment of the present application provides a matched filter circuit, including a first filter circuit, a first matching circuit, a second filter circuit and a second matching circuit; the input end of the first filter circuit is connected to the first input-output end and the source end of the first matching circuit, and the output end of the first filter circuit is grounded; the second input-output end of the first matching circuit is connected to the input end of the second filter circuit and the first input-output end of the second matching circuit, and the first output end and the second output end of the first matching circuit are grounded; the output end of the second filter circuit is grounded; the second input-output end of the second matching circuit is connected to the load end, and the first output end and the second output end of the second matching circuit are grounded, so that different source ends can adopt the matched filter circuit, which can solve the problems of spurious and RF performance debugging, has low debugging difficulty, shortens the development cycle and improves the version update speed.

[0039] It can be understood that the beneficial effects of the second aspect mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 This is a schematic diagram of the first structure of the matched filter circuit provided in the embodiment of the present application;

[0042] Figure 2 This is a second structural schematic diagram of a matched filter circuit provided in an embodiment of the present application;

[0043] Figure 3 is a circuit schematic diagram of a matched filter circuit provided in an embodiment of the present application;

[0044] Figure 4 is an application principle diagram of the first filtering circuit provided in an embodiment of the present application;

[0045] Figure 5 is an application effect diagram of the first filtering circuit provided in an embodiment of the present application;

[0046] Figure 6 is an application principle diagram of a first matching circuit provided in an embodiment of the present application;

[0047] Figure 7 is an application effect diagram of the first matching circuit provided in an embodiment of the present application;

[0048] Figure 8is an application principle diagram of the second filtering circuit provided in an embodiment of the present application;

[0049] Fig. 9 is an application effect diagram of the second filtering circuit provided in an embodiment of the present application;

[0050] Fig.10 is an application principle diagram of a second matching circuit provided in an embodiment of the present application;

[0051] Fig.11 This is an application effect diagram of the second matching circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0052] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0053] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0054] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0055] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0056] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0057] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways. "Multiple" means two or more.

[0058] An embodiment of the present application provides a matching filter circuit, which is applied to a radio frequency circuit, so that the source end of different radio frequency circuits can adopt the matching filter circuit to solve the spurious and radio frequency performance debugging problems. The debugging difficulty is low, the development cycle is shortened and the version update speed is improved.

[0059] like Figure 1 As shown, the matched filter circuit 100 provided in the embodiment of the present application includes a first filter circuit 10, a first matching circuit 20, a second filter circuit 30 and a second matching circuit 40;

[0060] The input end of the first filter circuit 10 is connected to the first input-output end of the first matching circuit 20 and the source end 200, and the output end of the first filter circuit 10 is grounded;

[0061] The second input and output end of the first matching circuit 20 is connected to the input end of the second filter circuit 30 and the first input and output end of the second matching circuit 40, and the first output end and the second output end of the first matching circuit 20 are grounded;

[0062] The output terminal of the second filter circuit 30 is grounded;

[0063] The second input and output terminals of the second matching circuit 40 are connected to the load terminal 300 , and the first output terminal and the second output terminal of the second matching circuit 40 are grounded.

[0064] In applications, the matched filter circuit is applied to the RF circuit. The RF circuit can be any RF circuit including a source end, a matched filter circuit and a load end. The source end can include a RF chip, a transceiver, a switch, a power amplifier, a noise amplifier, etc., and the load end can include a duplexer, a switch, an antenna, etc.

[0065] In application, the first filter circuit, the second filter circuit, the first matching circuit and the second matching circuit can all be realized by means of electronic components such as resistors, inductors and capacitors with certain impedance or filtering functions. The first filter circuit and the second filter circuit can be L-type filter circuits or π-type filter circuits, and the first matching circuit and the second matching circuit can be L-type matching circuits or π-type matching circuits.

[0066] In the application, the first filter circuit is used to suppress the stray interference in the signal output from the source end. In order to improve the filtering effect, the first filter circuit should be set as close to the source end as possible. The first matching circuit is used to solve the impedance discontinuity problem caused by the pad and the wiring structure of the motherboard. The second filter circuit is used to combine with the first filter circuit and the first matching circuit to form a matching circuit to suppress the stray signal caused by the impedance mutation of the transmission line and prevent the stray signal from being transmitted to the load end. The second matching circuit is used to match the impedance of the load.

[0067] like Figure 2 As shown, in one embodiment, the first filter circuit 10 includes a first inductor unit 11 and a first capacitor unit 12;

[0068] The input end of the first inductor unit 11 is the input end of the first filter circuit 10, and the output end of the first inductor unit 11 is connected to the input end of the first capacitor unit 12;

[0069] The output end of the first capacitor unit 12 is the output end of the first filter circuit 10 .

[0070] In application, the first filtering circuit can be an L-type filtering circuit composed of a first inductance unit and a first capacitance unit. The first inductance unit can be implemented by selecting at least one inductance or multiple inductances connected in series according to actual needs, and the first capacitance unit can be implemented by selecting a capacitor or multiple capacitors connected in parallel according to actual needs.

[0071] like Figure 2 As shown, in one embodiment, the first matching circuit 20 includes a second capacitor unit 21, a second inductor unit 22 and a third capacitor unit 23;

[0072] The input end of the second capacitor unit 21 and the first input and output end of the second inductor unit 22 are connected to form the first input and output end of the first matching circuit 20, and the output end of the second capacitor unit 21 is the first output end of the first matching circuit 20;

[0073] The second input-output end of the second inductor unit 22 and the input end of the third capacitor unit 23 are connected to form the second input-output end of the first matching circuit 20;

[0074] An output end of the third capacitor unit 23 is a second output end of the first matching circuit 20 .

[0075] In application, the first matching circuit can be a π-type matching circuit composed of a second capacitor unit, a second inductor unit and a third capacitor unit. The second capacitor unit and the third capacitor unit can select one capacitor or multiple capacitors in parallel according to actual needs, and the second inductor unit can select at least one inductor or multiple inductors in series according to actual needs.

[0076] like Figure 2 As shown, in one embodiment, the second filter circuit 30 includes a third inductor unit 31 and a fourth capacitor unit 32;

[0077] The input end of the third inductor unit 31 is the input end of the second filter circuit 30, and the output end of the third inductor unit 31 is connected to the input end of the fourth capacitor unit 32;

[0078] The output end of the fourth capacitor unit 32 is the output end of the second filter circuit 30 .

[0079] In application, the second filtering circuit can be an L-type filtering circuit composed of a third inductance unit and a fourth capacitance unit. The third inductance unit can be implemented by selecting at least one inductance or multiple inductances in series according to actual needs, and the fourth capacitance unit can be implemented by selecting a capacitor or multiple capacitors in parallel according to actual needs.

[0080] like Figure 2 As shown, in one embodiment, the second matching circuit 40 includes a fifth capacitor unit 41, a fourth inductor unit 42 and a sixth capacitor unit 43;

[0081] The input end of the fifth capacitor unit 41 and the first input-output end of the fourth inductor unit 42 are connected to form the first input-output end of the second matching circuit 40, and the output end of the fifth capacitor unit 41 is the first output end of the second matching circuit 40;

[0082] The second input-output end of the fourth inductor unit 42 and the input end of the sixth capacitor unit 43 are connected to form the second input-output end of the second matching circuit 40;

[0083] The output end of the sixth capacitor unit 43 is the second output end of the second matching circuit 40 .

[0084] In application, the second matching circuit can be a π-type matching circuit composed of a fifth capacitor unit, a fourth inductor unit and a sixth capacitor unit. The fifth capacitor unit and the sixth capacitor unit can be implemented by selecting one capacitor or multiple capacitors in parallel according to actual needs, and the fourth inductor unit can be implemented by selecting at least one inductor or multiple inductors in series according to actual needs.

[0085] like Figure 3As shown, in one embodiment, the first inductor unit 11 includes a first inductor L1, and the first capacitor unit 12 includes a first capacitor C1;

[0086] The input end and the output end of the first inductor L1 are respectively the input end and the output end of the first inductor unit 11;

[0087] The input end and the output end of the first capacitor C1 are the input end and the output end of the first capacitor unit 12 respectively.

[0088] In application, the first inductor and the first capacitor are connected in series to form an L-type filtering circuit. The parameters of the first inductor and the first capacitor can be selected according to actual needs. Specifically, the signal output by the source end can be tested by a network analyzer and a spectrum analyzer, and the parameters of the first inductor and the first capacitor can be continuously changed to debug the signal. Finally, the parameters of the first inductor and the first capacitor that minimize the stray interference in the output signal are selected. For example, the inductance of the first inductor is 1nH, and the capacitance of the first capacitor is 1pF.

[0089] like Figure 3 As shown, in one embodiment, the second capacitor unit 21 includes a second capacitor C2, the second inductor unit 22 includes a second inductor L2, and the third capacitor unit 23 includes a third capacitor C3;

[0090] The input end and the output end of the second capacitor C2 are respectively the input end and the output end of the second capacitor unit 21;

[0091] The first input-output terminal and the second input-output terminal of the second inductor L2 are respectively the first input-output terminal and the second input-output terminal of the second inductor unit 22;

[0092] The input end and the output end of the third capacitor C3 are respectively the input end and the output end of the third capacitor unit 23 .

[0093] In application, the second capacitor and the third capacitor are connected in parallel at both ends of the second inductor to form a π-type matching circuit. The parameters of the second capacitor, the second inductor and the third capacitor can be selected according to actual needs. Specifically, the signal output from the source end can be tested by a network analyzer and a spectrum analyzer, and the parameters of the second capacitor, the second inductor and the third capacitor can be continuously changed to debug the output signal. Finally, the parameters of the second capacitor, the second inductor and the third capacitor are selected so as to solve the impedance discontinuity problem caused by the pad and the wiring structure of the mainboard. For example, the capacitance of the second capacitor is 1.1pF, the inductance of the second inductor is 3.3nH, and the capacitance of the third capacitor is 1.1pF.

[0094] like Figure 3 As shown, in one embodiment, the third inductor unit 31 includes a third inductor L3, and the fourth capacitor unit 32 includes a fourth capacitor C4;

[0095] The input end and the output end of the third inductor L3 are respectively the input end and the output end of the third inductor unit 31;

[0096] The input terminal and the output terminal of the fourth capacitor C4 are respectively the input terminal and the output terminal of the fourth capacitor unit 32 .

[0097] In application, the third inductor and the fourth capacitor are connected in series to form an L-type filtering circuit. The parameters of the third inductor and the fourth capacitor can be selected according to actual needs. Specifically, the signal output by the source end can be tested by a network analyzer and a spectrum analyzer, and the parameters of the third inductor and the fourth capacitor can be continuously changed to debug the signal. Finally, the parameters of the third inductor and the fourth capacitor that minimize the stray interference in the output signal are selected. For example, the inductance of the third inductor is 1nH, and the capacitance of the first capacitor is 1pF.

[0098] like Figure 3 As shown, in one embodiment, the fifth capacitor unit 41 includes a fifth capacitor C5, the fourth inductor unit 42 includes a fourth inductor L4, and the sixth capacitor unit 43 includes a sixth capacitor C6;

[0099] The input end and the output end of the fifth capacitor C5 are respectively the input end and the output end of the fifth capacitor unit 41;

[0100] The first input-output terminal and the second input-output terminal of the fourth inductor L4 are respectively the first input-output terminal and the second input-output terminal of the fourth inductor unit 42;

[0101] The input terminal and the output terminal of the sixth capacitor C6 are respectively the input terminal and the output terminal of the sixth capacitor unit 43 .

[0102] In application, the fifth capacitor and the sixth capacitor are connected in parallel at both ends of the fourth inductor to form a π-type matching circuit. The parameters of the fifth capacitor, the fourth inductor and the sixth capacitor can be selected according to actual needs. Specifically, the signal received at the source end can be tested by a network analyzer and a spectrum analyzer, and the parameters of the fifth capacitor, the fourth inductor and the sixth capacitor can be continuously changed to debug the signal. Finally, the parameters of the fifth capacitor, the fourth inductor and the sixth capacitor that make the signal strength of the received signal the strongest (that is, the most matched with the impedance of the load) are selected. For example, the capacitance of the fifth capacitor is 1.5pF, the inductance of the fourth inductor is 3.3nH, and the capacitance of the sixth capacitor is 1.5pF.

[0103] like Figure 4As shown, an application schematic diagram of the first filter circuit 10 is exemplarily shown, wherein the L-type matching circuit formed by the fifth inductor L5 and the seventh capacitor C7 is an equivalent circuit of the first matching circuit 20, the second filter circuit 30 and the second matching circuit 40, and the first filter circuit 10 and the L-type matching circuit together constitute a matching filter circuit.

[0104] Figure 5 The diagram exemplarily shows the effect of applying the first filter circuit 10 to a 2.4G radio frequency circuit to suppress a 2x frequency signal; wherein the inductance of the first inductor L1 is 1nH, the capacitance of the first capacitor C1 is 1pF, the inductance of the fifth inductor L5 is 3.1nH, and the capacitance of the seventh capacitor C7 is 1pF. The left figure shows the frequency and loss of the 2.4G signal and the frequency and loss of the 2x frequency signal before applying the first filter circuit 10, and the right figure shows the frequency and loss of the 2.4G signal and the frequency and loss of the 2x frequency signal after applying the first filter circuit 10. Compare Figure 5 It can be seen from the middle left and right figures that the 2nd frequency signal is well suppressed.

[0105] like Figure 6 , which exemplarily shows an application principle diagram of the first matching circuit 20 , wherein the capacitance of the second capacitor C2 is 1.1 pF, the inductance of the second inductor L2 is 3.3 nH, and the capacitance of the third capacitor C3 is 1.1 pF.

[0106] Figure 7 The first matching circuit 20 is applied to a 2.4G radio frequency circuit to solve the impedance discontinuity problem. The left figure shows the frequency and loss of the 2.4G signal and the frequency and loss of the double frequency signal before the first matching circuit 20 is applied, and the right figure shows the frequency and loss of the 2.4G signal and the frequency and loss of the double frequency signal after the first matching circuit 20 is applied. Figure 7 It can be seen from the middle left and right pictures that the loss of 2.4G signal is significantly reduced and almost lossless.

[0107] like Figure 8 As shown, an application principle diagram of the second filter circuit 30 is exemplarily shown, wherein the first filter circuit 10, the second inductor L2 in the first matching circuit 20 and the second filter circuit 30 together form a matching filter circuit.

[0108] Fig. 9The diagram exemplarily shows the application effect of the second filter circuit 30 applied to the 2.4G radio frequency circuit to suppress the stray signal caused by the impedance mutation of the transmission line; wherein, the inductance of the first inductor L1 is 1nH, the capacitance of the first capacitor C1 is 1pF, the inductance of the second inductor L2 is 3.3nH, the inductance of the third inductor L3 is 1nH, and the capacitance of the fourth capacitor C4 is 1pF. The left figure shows the frequency and loss of the 2.4G signal and the frequency and loss of the 2x frequency signal before the application of the second filter circuit 20, and the right figure shows the frequency and loss of the 2.4G signal and the frequency and loss of the stray signal after the application of the first filter circuit 10. Compare Fig. 9 It can be seen from the middle left and right pictures that the loss of 2.4G signal is significantly reduced and almost lossless.

[0109] like Fig.10 , which exemplarily shows an application principle diagram of the second matching circuit 40 , wherein the capacitance of the fifth capacitor C5 is 1.5 pF, the inductance of the fourth inductor L4 is 3.3 nH, and the capacitance of the sixth capacitor C6 is 1.5 pF.

[0110] Fig.11 The second matching circuit 40 is applied to a 2.4G radio frequency circuit to match the load impedance. The left figure shows the frequency and loss of the 2.4G signal and the frequency and loss of the double frequency signal before the second matching circuit 40 is applied, and the right figure shows the frequency and loss of the 2.4G signal and the frequency and loss of the stray signal after the second matching circuit 40 is applied. Fig.11 It can be seen from the middle left and right pictures that the loss of 2.4G signal is significantly reduced and almost lossless.

[0111] An embodiment of the present application also provides a radio frequency circuit, including a source end, a load end, and the matching filter circuit in any of the above embodiments.

[0112] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A matched filter circuit, characterized in that: comprising a first filtering circuit, a first matching circuit, a second filtering circuit and a second matching circuit; The input end of the first filter circuit is connected to the first input-output end and the source end of the first matching circuit, and the output end of the first filter circuit is grounded; The second input and output end of the first matching circuit is connected to the input end of the second filter circuit and the first input and output end of the second matching circuit, and the first output end and the second output end of the first matching circuit are grounded; The output terminal of the second filtering circuit is grounded; The second input and output end of the second matching circuit is connected to the load end, and the first output end and the second output end of the second matching circuit are grounded; The first filter circuit includes a first inductor unit and a first capacitor unit; The input end of the first inductor unit is the input end of the first filter circuit, and the output end of the first inductor unit is connected to the input end of the first capacitor unit; The output end of the first capacitor unit is the output end of the first filter circuit; The first matching circuit includes a second capacitor unit, a second inductor unit and a third capacitor unit; The input end of the second capacitor unit and the first input and output end of the second inductor unit are connected to form the first input and output end of the first matching circuit, and the output end of the second capacitor unit is the first output end of the first matching circuit; The second input-output end of the second inductor unit and the input end of the third capacitor unit are connected to form the second input-output end of the first matching circuit; The output end of the third capacitor unit is the second output end of the first matching circuit; The second filtering circuit includes a third inductor unit and a fourth capacitor unit; The input end of the third inductor unit is the input end of the second filter circuit, and the output end of the third inductor unit is connected to the input end of the fourth capacitor unit; The output end of the fourth capacitor unit is the output end of the second filter circuit; The second matching circuit includes a fifth capacitor unit, a fourth inductor unit and a sixth capacitor unit; The input end of the fifth capacitor unit and the first input and output end of the fourth inductor unit are connected to form the first input and output end of the second matching circuit, and the output end of the fifth capacitor unit is the first output end of the second matching circuit; The second input-output end of the fourth inductor unit and the input end of the sixth capacitor unit are connected to form the second input-output end of the second matching circuit; The output end of the sixth capacitor unit is the second output end of the second matching circuit.

2. The matched filter circuit according to claim 1, characterized in that: The first inductor unit includes a first inductor, and the first capacitor unit includes a first capacitor; The input end and the output end of the first inductor are respectively the input end and the output end of the first inductor unit; The input end and the output end of the first capacitor are respectively the input end and the output end of the first capacitor unit.

3. The matched filter circuit according to claim 1, characterized in that: The second capacitor unit includes a second capacitor, the second inductor unit includes a second inductor, and the third capacitor unit includes a third capacitor; The input end and the output end of the second capacitor are respectively the input end and the output end of the second capacitor unit; The first input-output terminal and the second input-output terminal of the second inductor are respectively the first input-output terminal and the second input-output terminal of the second inductor unit; The input end and the output end of the third capacitor are respectively the input end and the output end of the third capacitor unit.

4. The matched filter circuit according to claim 1, characterized in that: The third inductor unit includes a third inductor, and the fourth capacitor unit includes a fourth capacitor; The input end and the output end of the third inductor are respectively the input end and the output end of the third inductor unit; The input end and the output end of the fourth capacitor are respectively the input end and the output end of the fourth capacitor unit.

5. The matched filter circuit according to claim 1, characterized in that: The fifth capacitor unit includes a fifth capacitor, the fourth inductor unit includes a fourth inductor, and the sixth capacitor unit includes a sixth capacitor; The input end and the output end of the fifth capacitor are respectively the input end and the output end of the fifth capacitor unit; The first input-output terminal and the second input-output terminal of the fourth inductor are respectively the first input-output terminal and the second input-output terminal of the fourth inductor unit; The input end and the output end of the sixth capacitor are respectively the input end and the output end of the sixth capacitor unit.

6. A radio frequency circuit, characterized in that: It comprises a source end, a load end and a matching filter circuit as claimed in any one of claims 1 to 5.

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