Antenna matching circuit and radio frequency circuit

Abstract

The utility model provides an antenna matching circuit and a radio frequency circuit, and relates to the technical field of radio frequency circuits. In the antenna matching circuit, the output end of a signal generation circuit is connected with the input end of a link module, an antenna is respectively connected with the output end of the link module and a coupling circuit, and a control circuit is respectively connected with the coupling circuit and the signal generation circuit; after receiving the test instruction of the control circuit, the signal generation circuit sends a test signal to a transmitting link connected with the coupling circuit; the coupling circuit sends a reflection signal corresponding to the test signal to the control circuit; the control circuit is used for triggering and outputting a link opening instruction for instructing the link module to open a transmitting link to the link module after receiving the reflected signal; and the link module is used for opening a transmitting link corresponding to the link opening instruction. According to the embodiment of the invention, the bandwidth of the radio frequency circuit is effectively expanded, the radio frequency circuit can adapt to different antennas conveniently, and the compatibility of the radio frequency circuit is enhanced.

Description

Technical Field

[0001] This application relates to the technical field of radio frequency circuits. Specifically, this application relates to an antenna matching circuit and a radio frequency circuit. Background Art

[0002] With the progress of wireless communication technology, wireless communication products have been widely used in daily life, and radio frequency circuits are one of the most important circuits in wireless communication products.

[0003] In the prior art, different antennas are matched at different frequencies. To improve the performance of radio frequency circuits, corresponding links need to be designed according to the characteristics of the antennas, resulting in that the links can only adapt to signals in a fixed frequency band and specific antennas for transmitting such signals, making the compatibility of radio frequency circuits poor and difficult to adapt to different antennas. Utility Model Content

[0004] Embodiments of this application provide an antenna matching circuit and a radio frequency circuit, which can solve the problems of poor compatibility of existing radio frequency circuits and difficulty in adapting to different frequency signals and different antennas. To achieve this purpose, the embodiments of this application provide the following several solutions.

[0005] According to one aspect of the embodiments of this application, an antenna matching circuit for a radio frequency circuit is provided. The antenna matching circuit includes: a signal generation circuit, a coupling circuit, an antenna, a control circuit, and a link module having at least one transmission link. The output end of the signal generation circuit is connected to the input end of the link module. The antenna is respectively connected to the output end of the link module and the coupling circuit. The control circuit is respectively connected to the coupling circuit and the signal generation circuit;

[0006] The signal generation circuit is configured to send a test signal to a transmission link connected to the coupling circuit after receiving a test instruction from the control circuit;

[0007] The coupling circuit is configured to send the test signal transmitted by the transmission link to the antenna and send the reflection signal corresponding to the test signal to the control circuit. The reflection signal is generated by the coupling circuit based on the reverse coupling of the antenna;

[0008] The control circuit is configured to trigger a link opening instruction indicating that the link module opens the transmission link to the link module after receiving the reflection signal;

[0009] The link module is configured to open the transmission link corresponding to the link opening instruction and close other transmission links to form a signal transmission path with the antenna through the transmission link corresponding to the link opening instruction.

[0010] In a possible implementation, the coupling circuit includes a directional coupler. The output end of the directional coupler is connected to the antenna and the first output end of the transmitting link in the link module. The coupled end and the isolation end of the directional coupler are both connected to the control circuit, and the input end of the directional coupler is connected to the second output end of a transmitting link in the link module.

[0011] In a possible implementation, the control circuit includes a first switch circuit, a detector, an analog-to-digital converter, and a controller connected in sequence. The input end of the first switch circuit is connected to the coupling circuit, and the controller is connected to the signal generation circuit and the link module respectively.

[0012] In a possible implementation, the link module includes at least one link switching switch. The output end of each transmitting link is correspondingly connected to a link switching switch, and each link switching switch is connected to the antenna, the controller, and the coupling circuit.

[0013] In a possible implementation, the link module includes a first transmitting link and a second transmitting link. The link switching switches include a first switching switch and a second switching switch. The control ends of the first switching switch and the second switching switch are connected to the controller;

[0014] The output end of the first transmitting link is connected to the input end of the first switching switch. The first output end of the first switching switch is connected to the antenna, and the second output end of the first switching switch is connected to the coupling circuit;

[0015] The output end of the second transmitting link is connected to the input end of the second switching switch. The first output end of the second switching switch is connected to the antenna.

[0016] In a possible implementation, the circuit structures of the first transmitting link and the second transmitting link are the same, and the parameters of at least some components in the first transmitting link and the second transmitting link are different.

[0017] In a possible implementation, the first transmission link includes a tenth capacitor, an eleventh capacitor, a seventh inductor, a thirteenth capacitor, an eighth inductor, a twelfth capacitor, and a fifth resistor. The first end of the tenth capacitor is connected to the first signal output terminal of the signal generation circuit. The second end of the tenth capacitor is connected to the first end of the seventh inductor and the first end of the twelfth capacitor. The second end of the seventh inductor is grounded. The second end of the twelfth capacitor is connected to the first end of the fifth resistor and the second end of the eighth inductor. The first end of the eighth inductor is connected to the first end of the thirteenth capacitor and the second end of the eleventh capacitor. The second end of the thirteenth capacitor is grounded. The first end of the eleventh capacitor is connected to the second signal output terminal of the signal generation circuit.

[0018] In a possible implementation, the first switch circuit includes a first RF switch, a first inductor, a first capacitor, and a second inductor. The first end of the first inductor is connected to the first end of the first capacitor and the coupling circuit. The second end of the first inductor is grounded. The second end of the first capacitor is connected to the first end of the second inductor and the signal receiving terminal of the first RF switch. The second end of the second inductor is grounded. The control terminal of the first RF switch is connected to the controller. The signal output terminal of the first RF switch is connected to the detector.

[0019] In a possible implementation, the detector includes an RF detector, a third capacitor, a fourth capacitor, a first resistor, a third resistor, and a fourth resistor. The second end of the fourth capacitor is grounded, and the first end is connected to the output terminal of the first switch circuit and the first end of the third capacitor. The second end of the third capacitor is connected to the first end of the first resistor and the signal receiving terminal of the RF detector. The second end of the first resistor is grounded. The signal output terminal of the RF detector is connected to the first end of the fourth resistor and the second end of the third resistor. The first end of the third resistor is connected to the voltage setting terminal of the RF detector. The second end of the fourth resistor is connected to the analog-to-digital converter.

[0020] According to one aspect of the embodiments of the present application, a radio frequency circuit is provided, and the radio frequency circuit includes the antenna matching circuit as described above.

[0021] The beneficial effects brought by the technical solutions provided by the embodiments of the present application are:

[0022] In the antenna matching circuit provided by the present application, the output end of the signal generation circuit is connected to the input end of the link module, the antenna is respectively connected to the output end of the link module and the coupling circuit, and the control circuit is respectively connected to the coupling circuit and the signal generation circuit; the signal generation circuit is configured to send a test signal to the transmitting link connected to the coupling circuit after receiving a test instruction from the control circuit; the coupling circuit is configured to send the test signal transmitted by the transmitting link to the antenna and send the reflection signal corresponding to the test signal to the control circuit; the control circuit is configured to receive the reflection signal and trigger and output a link opening instruction to the link module to indicate that the link module opens the transmitting link; the link module is configured to open the transmitting link corresponding to the link opening instruction and close other transmitting links to form a signal transmission path with the antenna through the transmitting link corresponding to the link opening instruction. The embodiments of the present application can quickly detect the transmitting link corresponding to the frequency band matched with the antenna and control the operation of the transmitting link, effectively expand the bandwidth of the radio frequency circuit and facilitate the radio frequency circuit to adapt to different antennas, enhancing the compatibility of the radio frequency circuit. Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments of the present application.

[0024] Figure 1 Structural diagram of the antenna matching circuit provided by the embodiments of the present application;

[0025] Figure 2 Circuit diagram of the controller provided by the embodiments of the present application;

[0026] Figure 3 Circuit diagram of the signal generation circuit, the link module and the coupling circuit provided by the embodiments of the present application;

[0027] Figure 4 Circuit diagram of the first switch circuit provided by the embodiments of the present application;

[0028] Figure 5 Circuit diagram of the detector provided by the embodiments of the present application;

[0029] Figure 6 Circuit diagram of the analog-to-digital converter provided by the embodiments of the present application;

[0030] Figure 7 Structural diagram of the radio frequency circuit provided by the embodiments of the present application.

[0031] Label description: U4, transmitting chip; X1, directional coupler; U3, analog-to-digital converter; U7, controller; U5, first switching switch; U6, second switching switch; C10, tenth capacitor; C11, eleventh capacitor; L7, seventh inductor; C13, thirteenth capacitor; L8, eighth inductor; C12, twelfth capacitor; R5, fifth resistor; C17, seventeenth capacitor; L10, tenth inductor; C15, fifteenth capacitor; R6, sixth resistor; L9, ninth inductor; C14, fourteenth capacitor; C16, sixteenth capacitor; U1, first RF switch; L1, first inductor; C1, first capacitor; L2, second inductor; U2, RF detector; C3, third capacitor; C4, fourth capacitor; R1, first resistor; R3, third resistor; R4, fourth resistor; L4, fourth inductor; C2, second capacitor; L3, third inductor. Detailed implementation

[0032] The embodiments of the present application will be described below with reference to the drawings in the present application. It should be understood that the embodiments described below in conjunction with the drawings are exemplary descriptions for explaining the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions of the embodiments of the present application.

[0033] Those skilled in the art of the present technology can understand that, unless specifically stated otherwise, the singular forms "a", "an", "the", and "said" used herein may also include the plural forms. It should be further understood that the terms "including" and "comprising" used in the embodiments of the present application mean that the corresponding features can be implemented as the presented features, information, data, steps, operations, elements, and / or components, but do not exclude the implementation of other features, information, data, steps, operations, elements, components, and / or their combinations supported by the art of the present technology. It should be understood that when we say an element is "connected" or "coupled" to another element, the one element can be directly connected or coupled to the other element, or it can mean that the one element and the other element establish a connection relationship through an intermediate element. In addition, the "connection" or "coupling" used here can include wireless connection or wireless coupling. The term "and / or" used here indicates at least one of the items defined by the term, for example, "A and / or B" indicates being implemented as "A", or being implemented as "B", or being implemented as "A and B".

[0034] To make the purpose, technical solutions, and advantages of the present utility model clearer, the embodiments of the present utility model will be described in further detail below with reference to the drawings.

[0035] The technical solutions of the embodiments of the present utility model and the technical effects generated by the technical solutions of the present utility model will be described below through the description of several exemplary embodiments. It should be noted that the following embodiments can be referred to, learned from, or combined with each other. For the same terms, similar features, and similar implementation steps in different embodiments, they will not be described repeatedly.

[0036] The antenna matching circuit and the radio frequency circuit provided in the present application are intended to solve at least one technical problem existing in the prior art.

[0037] An antenna matching circuit is provided in an embodiment of the present application, as Figures 1-6 shown, for a radio frequency circuit. The antenna matching circuit includes: a signal generation circuit, a coupling circuit, an antenna, a control circuit, and a link module having at least one transmission link. The output end of the signal generation circuit is connected to the input end of the link module. The antenna is respectively connected to the output end of the link module and the coupling circuit. The control circuit is respectively connected to the coupling circuit and the signal generation circuit. The signal generation circuit is configured to send a test signal to a transmission link connected to the coupling circuit after receiving a test instruction from the control circuit. The coupling circuit is configured to send the test signal transmitted by the transmission link to the antenna and send the reflection signal corresponding to the test signal to the control circuit. The reflection signal is generated by the coupling circuit based on the reverse coupling of the antenna. The control circuit is configured to trigger and output a link opening instruction for indicating that the link module opens the transmission link after receiving the reflection signal. The link module is configured to open the transmission link corresponding to the link opening instruction and close other transmission links to form a signal transmission path with the antenna through the transmission link corresponding to the link opening instruction.

[0038] Optionally, the signal generation circuit includes a transmitting chip U4. The control circuit sends a test signal through the transmitting chip U4, as Figure 3 shown. The model of the transmitting chip U4 can be BK9535. The frequency band of the test signal sent by the transmitting chip U4 can be the frequency band matched by a certain transmission link in the link module. And the control circuit can send multiple test signals through the transmitting chip U4. Each test signal corresponds to the frequency band matched by a transmission link. The frequency band matched by the currently connected antenna is detected through the multiple test signals (when the antenna matches the frequency band corresponding to the test signal, the power of the reflection signal is low).

[0039] Optionally, the antenna matching circuit can be arranged in the signal transmitting circuit of the radio frequency circuit. The radio frequency circuit sends wireless signals through the antenna matching circuit, or can be arranged in the signal receiving circuit of the radio frequency circuit to receive wireless signals through the antenna matching circuit.

[0040] Optionally, there may be multiple antennas in the antenna matching circuit, where different antennas match different signal frequencies, and the user can select the link module and the antenna connected to the coupling circuit according to their own needs.

[0041] Optionally, the coupling circuit includes a directional coupler X1. The output end of the directional coupler X1 is connected to the antenna and the first output end of the transmitting link in the link module. The coupling end and the isolation end of the directional coupler X1 are both connected to the control circuit, and the input end of the directional coupler X1 is connected to the second output end of a transmitting link in the link module.

[0042] In one embodiment, as Figure 3 shown, the model of the directional coupler X1 is DBTC-17-5+. The third port and the fourth port of the directional coupler X1 are connected to the link module, and the first port and the sixth port are connected to the control circuit.

[0043] Optionally, the control circuit includes a first switch circuit, a detector, an analog-to-digital converter U3, and a controller U7 connected in sequence. The input end of the first switch circuit is connected to the coupling circuit, and the controller U7 is respectively connected to the signal generation circuit and the link module.

[0044] Optionally, the controller U7 may include a comparison circuit and an instruction generation circuit. The comparison circuit receives the signal output by the analog-to-digital converter U3, compares the power intensity of the signal with a predetermined intensity range. If the intensity is lower than a certain predetermined intensity value, that is, the current antenna matches the frequency band corresponding to the predetermined intensity value, then the corresponding signal is output. The corresponding signal is output to the instruction generation circuit, and the instruction generation circuit generates a link activation instruction based on the corresponding signal. In this way, the corresponding transmitting link can be activated according to the antenna, realizing the matching of different transmitting links with the corresponding antennas, and each transmitting link operates in its corresponding frequency band, improving the performance of the antenna matching circuit.

[0045] In one embodiment, as Figure 2 shown, the controller U7 can be a single-chip microcomputer, and its model can be N32L406CBL7. The model of the analog-to-digital converter U3 can be ADS7229IPW. The analog-to-digital converter U3 collects the analog signal output by the detector and converts the analog signal into a digital signal and outputs it to the controller U7.

[0046] Optionally, the link module includes at least one link switching switch. The output end of each transmitting link is correspondingly connected to a link switching switch, and each link switching switch is connected to the antenna and the controller U7. The coupling circuit is connected to one link switching switch. Among them, different transmitting links match different signal frequencies.

[0047] Optionally, the link module includes a first transmission link and a second transmission link. The link switching switch includes a first switching switch U5 and a second switching switch U6. The control ends of the first switching switch U5 and the second switching switch U6 are connected to the controller U7. The output end of the first transmission link is connected to the input end of the first switching switch U5. The first output end of the first switching switch U5 is connected to the antenna, and the second output end of the first switching switch U5 is connected to the coupling circuit. The output end of the second transmission link is connected to the input end of the second switching switch U6, and the first output end of the second switching switch U6 is connected to the antenna. Among them, both the first switching switch U5 and the second switching switch U6 are RF switches.

[0048] In one embodiment, as Figure 3 shown, the models of both the first switching switch U5 and the second switching switch U6 are PE4259-63. The fourth ports of the first switching switch U5 and the second switching switch U6 are connected to the controller U7. The first switching switch U5 and the second switching switch U6 perform operations of whether to transmit signals to the antenna and the coupling circuit according to the instructions transmitted through the fourth ports.

[0049] Optionally, the circuit structures of the first transmission link and the second transmission link are the same. Both are provided with the same number and the same types of components, and at least some of the parameters of the components in the first transmission link and the second transmission link are different.

[0050] In one embodiment, the first transmission link includes a tenth capacitor C10, an eleventh capacitor C11, a seventh inductor L7, a thirteenth capacitor C13, an eighth inductor L8, a twelfth capacitor C12, and a fifth resistor R5. The first end of the tenth capacitor C10 is connected to the first signal output end of the signal generation circuit. The second end of the tenth capacitor C10 is connected to the first end of the seventh inductor L7 and the first end of the twelfth capacitor C12. The second end of the seventh inductor L7 is grounded. The second end of the twelfth capacitor C12 is connected to the first end of the fifth resistor R5 and the second end of the eighth inductor L8. The first end of the eighth inductor L8 is connected to the first end of the thirteenth capacitor C13 and the second end of the eleventh capacitor C11. The second end of the thirteenth capacitor C13 is grounded. The first end of the eleventh capacitor C11 is connected to the second signal output end of the signal generation circuit.

[0051] In one embodiment, the signal generation circuit transmits a test signal to the first transmission link, and the first transmission link transmits the signal to the first switching switch U5. The fifth port of the first switching switch U5 is connected to the first transmission link, the fourth port is connected to the controller U7, and when the fourth port and the sixth port of the first switching switch U5 are at high level, the fifth port is connected to the first port. When the sixth port is at high level and the fourth port is at low level, the fifth port is connected to the third port. The first port of the first switching switch U5 is connected to the antenna and the output end of the directional coupler X1, and the third port is connected to the input end of the directional coupler X1. When the first transmission link transmits the test signal, the controller U7 transmits a low-level signal to the fourth port of the first switching switch U5, and the test signal is transmitted from the fifth port to the third port, that is, to the input end of the directional coupler X1. The directional coupler X1 outputs signals through the output end and the coupling end.

[0052] The second transmission link includes the seventeenth capacitor C17, the tenth inductor L10, the fifteenth capacitor C15, the sixth resistor R6, the ninth inductor L9, the fourteenth capacitor C14, and the sixteenth capacitor C16. The first end of the seventeenth capacitor C17 is connected to the first signal output end of the signal generation circuit, the second end of the seventeenth capacitor C17 is connected to the first end of the tenth inductor L10 and the first end of the fifteenth capacitor C15, the second end of the tenth inductor L10 is grounded, the second end of the fifteenth capacitor C15 is connected to the first end of the sixth resistor R6 and the second end of the ninth inductor L9, the second end of the sixth resistor R6 is connected to the second switching switch U6, the first end of the ninth inductor L9 is connected to the first end of the fourteenth capacitor C14 and the second end of the sixteenth capacitor C16, the second end of the fourteenth capacitor C14 is grounded, and the first end of the sixteenth capacitor C16 is connected to the second signal output end of the signal generation circuit.

[0053] Optionally, the first switch circuit includes the first radio frequency switch U1, the first inductor L1, the first capacitor C1, and the second inductor L2. The first end of the first inductor L1 is connected to the first end of the first capacitor C1 and the coupling circuit, the second end of the first inductor L1 is grounded, the second end of the first capacitor C1 is connected to the first end of the second inductor L2 and the signal receiving end of the first radio frequency switch U1, the second end of the second inductor L2 is grounded, the control end of the first radio frequency switch U1 is connected to the controller U7, and the signal output end of the first radio frequency switch U1 is connected to the detector.

[0054] In one embodiment, as Figure 4As shown, the model of the first RF switch U1 is HMC547ALP3E, which is a non-reflective RF switch. The maximum frequency of the system is 1 GHz, while the frequency of the switch is 0 - 28 GHz, meeting the usage requirements of the RF circuit. The first RF switch U1 transmits signals to the detector through the third port. Among them, the first switch circuit further includes a fourth inductor L4, a second capacitor C2, and a third inductor L3. The first end of the fourth inductor L4 is connected to the fourteenth port of the first RF switch U1 and the first end of the second capacitor C2. The second end of the fourth inductor L4 is grounded. The second end of the second capacitor C2 is connected to the first end of the third inductor L3 and the sixth port of the directional coupler X1. The second end of the third inductor L3 is grounded. The working principle of the first RF switch U1 is as follows: When the eleventh port and the tenth port of the first RF switch U1 are at high level and low level respectively, the third port of the first RF switch U1 is connected to the seventh port, and the fourteenth port is connected to the 50Ω resistor inside the first RF switch U1. When the eleventh port and the tenth port are at low level and high level respectively, the third port is connected to the fourteenth port, and the seventh port is connected to the 50Ω resistor inside the first RF switch U1. At this time, the controller U7 outputs high level and low level to the eleventh port and the tenth port respectively. The fourteenth port is connected to the 50-ohm resistor inside the first RF switch U1, that is, the coupling end is connected to the 50-ohm resistor, and the third port is connected to the detector. The reflected signal output from the coupling pin of the directional coupler X1 is transmitted to the detector through the third port of the first RF switch U1.

[0055] Optionally, the detector includes an RF detector U2, a third capacitor C3, a fourth capacitor C4, a first resistor R1, a third resistor R3, and a fourth resistor R4. The second end of the fourth capacitor C4 is grounded, and the first end is connected to the output end of the first switch circuit and the first end of the third capacitor C3. The second end of the third capacitor C3 is connected to the first end of the first resistor R1 and the signal receiving end of the RF detector U2. The second end of the first resistor R1 is grounded. The signal output end of the RF detector U2 is connected to the first end of the fourth resistor R4 and the second end of the third resistor R3. The first end of the third resistor R3 is connected to the voltage setting end of the RF detector U2. The second end of the fourth resistor R4 is connected to the analog-to-digital converter U3.

[0056] In one embodiment, as Figure 5As shown, the model of the RF detector U2 is ADL5513ACPZ-R7. There is a relationship between the received power intensity and the output voltage. After the detector receives the reflected signal, it outputs a signal with a corresponding voltage value according to the power of the reflected signal. This signal is transmitted to the analog-to-digital converter U3 through the signal output terminal (the twelfth port). The third port of the analog-to-digital converter U3 is connected to the RF detector U2. The analog-to-digital converter U3 receives the analog signal transmitted by the RF detector U2, converts it into a digital signal, and transmits it to the controller U7 through the SPI protocol. The controller U7 outputs a link activation instruction based on this digital signal. Among them, if the transmitting link with antenna matching is already working, the link switching switch corresponding to this transmitting link is controlled by this link activation instruction to directly transmit the signal to the antenna.

[0057] Specifically, as Figure 6 shown, the model of the analog-to-digital converter U3 can be ADS7229IPW. After the controller U7 receives the digital signal from the analog-to-digital converter U3, it analyzes this digital signal based on the internal circuit. When the test signal is a single-carrier signal and the frequency of the single-carrier signal is 500 MHz, the controller U7 detects that the voltage of the digital signal is 1.6 V, that is, the power value of the reflected signal is -10 to -15 dbm. This power is greater than the predetermined power value (used to indicate the power value matching the current signal frequency and the antenna), that is, the power reflected by the antenna is relatively large and the frequency is mismatched; if it is less than this predetermined power value (unknown), it means that the power reflected by the antenna is very small, then the frequency matching this antenna is 500 MHz. The controller U7 sends an instruction indicating the activation of the corresponding transmitting link based on the comparison result. Among them, if the frequency band matched by the antenna is the A frequency band, the first transmitting link corresponding to the A frequency band can be activated and the second transmitting link can be closed. If the frequency band matched by the antenna is the B frequency band, the second transmitting link corresponding to the B frequency band can be activated and the first transmitting link can be closed.

[0058] In the embodiment of the present application, the antenna is connected through a directional coupler. The directional coupler outputs the reflected signal, and the reflected signal is then output to the controller through a detector and an analog-to-digital converter for analysis, so as to complete the judgment of the frequency band matched by the antenna, and then switch to the corresponding transmitting link. The present application has a high fault tolerance rate, a simple implementation method and low cost.

[0059] According to one aspect of the embodiment of the present application, a radio frequency circuit is further provided, as Figure 7 shown, this radio frequency circuit includes the antenna matching circuit as described in the above embodiment.

[0060] The terms "first", "second", "third", "fourth", "1", "2", etc. (if any) in the description, claims and the above-mentioned drawings of this application are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of this application described herein can be implemented in an order other than that shown or described in words.

[0061] It should be understood that although the flowchart of the embodiments of this application indicates each operation step by an arrow, the execution order of these steps is not limited to the order indicated by the arrow. Unless there is a clear description in this article, in some implementation scenarios of the embodiments of this application, the implementation steps in each flowchart can be executed in other orders according to requirements. In addition, some or all of the steps in each flowchart may include multiple sub-steps or multiple stages based on the actual implementation scenario. Some or all of these sub-steps or stages can be executed at the same time, and each sub-step or stage in these sub-steps or stages can also be executed at different times respectively. In the scenario where the execution times are different, the execution order of these sub-steps or stages can be flexibly configured according to requirements, and the embodiments of this application do not limit this.

[0062] The above are only optional implementation manners of some implementation scenarios of this application. It should be noted that for those of ordinary skill in the art, without departing from the technical concept of the solution of this application, adopting other similar implementation means based on the technical idea of this application also belongs to the protection scope of the embodiments of this application.

Claims

1. An antenna matching circuit, characterized in that, For a radio frequency circuit, the antenna matching circuit includes: a signal generation circuit, a coupling circuit, an antenna, a control circuit, and a link module having at least one transmission link. The output end of the signal generation circuit is connected to the input end of the link module. The antenna is respectively connected to the output end of the link module and the coupling circuit. The control circuit is respectively connected to the coupling circuit and the signal generation circuit; The signal generation circuit is configured to send a test signal to a transmission link connected to the coupling circuit after receiving a test instruction from the control circuit; The coupling circuit is configured to send the test signal transmitted by the transmission link to the antenna and send the reflection signal corresponding to the test signal to the control circuit. The reflection signal is generated by the coupling circuit based on the reverse coupling of the antenna; The control circuit is configured to, after receiving the reflection signal, trigger and output a link activation instruction to the link module to indicate that the link module activates the transmission link; The link module is configured to activate the transmission link corresponding to the link activation instruction and deactivate other transmission links to form a signal transmission path with the antenna through the transmission link corresponding to the link activation instruction.

2. The antenna matching circuit according to claim 1, wherein The coupling circuit includes a directional coupler. The output end of the directional coupler is connected to the antenna and the first output end of the transmission link in the link module. The coupling end and the isolation end of the directional coupler are both connected to the control circuit, and the input end of the directional coupler is connected to the second output end of a transmission link in the link module.

3. The antenna matching circuit according to claim 1, characterized in that The control circuit includes a first switch circuit, a detector, an analog-to-digital converter, and a controller connected in sequence. The input end of the first switch circuit is connected to the coupling circuit. The controller is respectively connected to the signal generation circuit and the link module.

4. The antenna matching circuit according to claim 3, wherein The link module includes at least one link switching switch. The output end of each transmission link is correspondingly connected to a link switching switch, and each link switching switch is connected to the antenna, the controller, and the coupling circuit.

5. The antenna matching circuit according to claim 4, wherein The link module includes a first transmission link and a second transmission link. The link switching switch includes a first switching switch and a second switching switch. The control ends of the first switching switch and the second switching switch are connected to the controller; The output end of the first transmission link is connected to the input end of the first switching switch. The first output end of the first switching switch is connected to the antenna. The second output end of the first switching switch is connected to the coupling circuit; The output end of the second transmission connection is connected to the input end of the second switching switch. The first output end of the second switching switch is connected to the antenna.

6. The antenna matching circuit according to claim 5, wherein The circuit structures of the first transmission link and the second transmission link are the same, and at least some of the parameters of the components in the first transmission link and the second transmission link are different.

7. The antenna matching circuit according to claim 6, wherein The first transmission link includes a tenth capacitor, an eleventh capacitor, a seventh inductor, a thirteenth capacitor, an eighth inductor, a twelfth capacitor, and a fifth resistor. The first end of the tenth capacitor is connected to the first signal output end of the signal generation circuit. The second end of the tenth capacitor is connected to the first end of the seventh inductor and the first end of the twelfth capacitor. The second end of the seventh inductor is grounded. The second end of the twelfth capacitor is connected to the first end of the fifth resistor and the second end of the eighth inductor. The first end of the eighth inductor is connected to the first end of the thirteenth capacitor and the second end of the eleventh capacitor. The second end of the thirteenth capacitor is grounded. The first end of the eleventh capacitor is connected to the second signal output end of the signal generation circuit.

8. The antenna matching circuit according to claim 3, wherein The first switching circuit includes a first RF switch, a first inductor, a first capacitor, and a second inductor. The first end of the first inductor is connected to the first end of the first capacitor and the coupling circuit. The second end of the first inductor is grounded. The second end of the first capacitor is connected to the first end of the second inductor and the signal receiving end of the first RF switch. The second end of the second inductor is grounded. The control end of the first RF switch is connected to the controller. The signal output end of the first RF switch is connected to the detector.

9. The antenna matching circuit according to claim 3, wherein The detector includes an RF detector, a third capacitor, a fourth capacitor, a first resistor, a third resistor, and a fourth resistor. The second end of the fourth capacitor is grounded, and the first end is connected to the output end of the first switching circuit and the first end of the third capacitor. The second end of the third capacitor is connected to the first end of the first resistor and the signal receiving end of the RF detector. The second end of the first resistor is grounded. The signal output end of the RF detector is connected to the first end of the fourth resistor and the second end of the third resistor. The first end of the third resistor is connected to the voltage setting end of the RF detector. The second end of the fourth resistor is connected to the analog-to-digital converter.

10. A radio frequency circuit, characterized in that, The RF circuit includes the antenna matching circuit according to any one of claims 1-9.

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