A radio frequency front-end circuit
By using a circularly polarized antenna module with a design that suppresses mismatched couplers and double-layer surround wiring, the impedance mismatch problem of miniaturized L/S band circularly polarized active antennas in complex environments is solved, improving the output power and reliability of the RF front-end system and ensuring communication stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GUANGZHOU HUIZHI MICROELECTRONICS
- Filing Date
- 2025-11-07
- Publication Date
- 2026-06-26
AI Technical Summary
Miniaturized L/S band circularly polarized active antennas are prone to impedance mismatch due to temperature changes and mechanical vibrations in complex environments, which affects the stability of RF power amplifiers and restricts the reliability of terminal antennas and communication quality.
The circularly polarized antenna module, which employs a mismatch-suppressing coupler and a double-layer surround wiring design, combined with an amplification module and adjustment circuit, suppresses the effects of impedance mismatch and improves reliability through power combining and reflected power absorption.
It significantly improves the output power and reliability of the RF front-end system, prevents RF power amplifier oscillation and burnout, and enhances communication stability and anti-interference capability in complex environments.
Smart Images
Figure CN121124846B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of radio frequency circuit technology, and in particular to a radio frequency front-end circuit. Background Technology
[0002] Currently, satellite communication technology, as a key infrastructure of modern information society, relies heavily on the technical performance of its front-end antenna components. Among these, miniaturized L / S (long-wave / short-wave) band circularly polarized active antenna systems for terminal devices have significant application value in satellite navigation, emergency communication, and the Internet of Things (IoT). However, current miniaturized L / S band circularly polarized active antenna technology still faces multiple challenges, with insufficient environmental adaptability being particularly prominent. Environmental factors such as temperature changes and mechanical vibrations can easily cause significant alterations in antenna impedance characteristics, leading not only to severe impedance mismatch but also to deterioration of the RF power amplifier's operating condition. This, in turn, has a cascading negative impact on the stability of the entire RF front-end system, severely restricting the reliability and communication quality of the terminal antenna in complex environments. Summary of the Invention
[0003] This disclosure provides an embodiment of a radio frequency front-end circuit.
[0004] The technical solution of this disclosure embodiment is implemented as follows:
[0005] This disclosure provides a radio frequency (RF) front-end circuit, comprising: an amplification module configured to receive a first RF signal from an RF source and amplify the first RF signal into a second RF signal; and a circularly polarized antenna module coupled to the output terminal of the amplification module, configured to receive the second RF signal, convert the second RF signal into an electromagnetic wave, and transmit it; the circularly polarized antenna module includes: a mismatch suppression coupler and an antenna; one of the first and second input terminals of the mismatch suppression coupler is connected to the output terminal of the second RF signal, the other input terminal of the first and second input terminals of the mismatch suppression coupler is connected to a ground terminal, and the first and second output terminals of the mismatch suppression coupler are connected to the antenna.
[0006] In some embodiments of this disclosure, the two coupling lines of the mismatch suppression coupler have a double-layer structure and are wired around each other; wherein the upper layer wiring and the lower layer wiring are symmetrical to each other.
[0007] In some embodiments of this disclosure, the circularly polarized antenna module further includes: a first single-pole double-throw (SPD) switch and a second SPD switch; the common terminal of the first SPD switch is connected to the first input terminal of the mismatch suppression coupler, the first throw point of the first SPD switch is connected to the second radio frequency (RF) signal output terminal, and the second throw point of the first SPD switch is connected to the ground terminal; the common terminal of the second SPD switch is connected to the second input terminal of the mismatch suppression coupler, the first throw point of the second SPD switch is connected to the second RF signal output terminal, and the second throw point of the second SPD switch is connected to the ground terminal; when the common terminal of the first SPD switch is connected to the first throw point of the first SPD switch, the common terminal of the second SPD switch is connected to the second throw point of the second SPD switch; when the common terminal of the first SPD switch is connected to the second throw point of the first SPD switch, the common terminal of the second SPD switch is connected to the first throw point of the second SPD switch.
[0008] In some embodiments of this disclosure, the antenna includes: a planar antenna; and a first output terminal and a second output terminal of the mismatch suppression coupler, which are respectively connected to two feed points of the planar antenna.
[0009] In some embodiments of this disclosure, the antenna includes: two linearly polarized antennas; the first output terminal and the second output terminal of the mismatch suppression coupler are respectively connected to the feed points of the two linearly polarized antennas.
[0010] In some embodiments of this disclosure, the two linearly polarized antennas are orthogonally arranged; the first and second output terminals of the mismatch suppression coupler output two orthogonal signals with a phase difference of 90°.
[0011] In some embodiments of this disclosure, the circularly polarized antenna module further includes: a first adjustment circuit and a second adjustment circuit; when the common terminal of the first single-pole double-throw switch is connected to the second throw point of the first single-pole double-throw switch, it is connected to the ground terminal through the first adjustment circuit; when the common terminal of the second single-pole double-throw switch is connected to the second throw point of the second single-pole double-throw switch, it is connected to the ground terminal through the second adjustment circuit.
[0012] In some embodiments of this disclosure, the first adjustment circuit and the second adjustment circuit include: a resistor and a capacitor; the resistor and the capacitor are connected in series, or the resistor and the capacitor are connected in parallel; the values of the capacitor and the resistor are adjustable.
[0013] In some embodiments of this disclosure, the amplification module includes: an input coupler, a first power amplifier, a second power amplifier, and an output coupler; the first input terminal of the input coupler receives a first radio frequency signal, the second input terminal of the input coupler is connected to the ground terminal, the first output terminal of the input coupler is connected to the input terminal of the first power amplifier, and the second output terminal of the input coupler is connected to the input terminal of the second power amplifier; the output terminal of the first power amplifier is connected to the first input terminal of the output coupler, the output terminal of the second power amplifier is connected to the second input terminal of the output coupler, the first output terminal of the output coupler outputs a second radio frequency signal, and the second output terminal of the output coupler is connected to the ground terminal.
[0014] In some embodiments of this disclosure, the second input terminal of the input coupler and the second output terminal of the output coupler are connected to the ground terminal through an impedance-adjustable load circuit.
[0015] Therefore, in this embodiment, the circuit amplifies the received first radio frequency signal into a second radio frequency signal and outputs the second radio frequency signal to the input of the mismatch suppression coupler. The mismatch suppression coupler splits the second radio frequency signal into two signals and transmits them to the antenna. The antenna converts the second radio frequency signal into electromagnetic waves and transmits them. Compared with traditional single-ended amplifiers, the amplification module not only significantly improves the output power through the power combining mechanism of the coupler, but also suppresses the adverse effects of antenna mismatch through the coupler. Simultaneously, the mismatch suppression coupler connected to the output of the amplification module can absorb reflected power, further suppressing the effects of antenna mismatch, improving reliability, and solving problems such as oscillation and burnout of the radio frequency power amplifier caused by impedance mismatch in traditional designs. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:
[0017] Figure 1 Schematic diagram of the radio frequency front-end circuit provided in the embodiments of this application Figure 1 ;
[0018] Figure 2 Schematic diagram of the radio frequency front-end circuit provided in the embodiments of this application Figure 2 ;
[0019] Figure 3 Schematic diagram of the radio frequency front-end circuit provided in the embodiments of this application Figure 3 ;
[0020] Figure 4 A schematic diagram of the structure of the circularly polarized antenna module provided in the embodiments of this application. Figure 1 ;
[0021] Figure 5 This is a schematic diagram of the upper-layer wiring structure of the coupling line of the mismatch suppression coupler provided in the embodiments of this application;
[0022] Figure 6 This is a schematic diagram of the lower-level routing structure of the coupling line of the suppression mismatch coupler provided in an embodiment of this application;
[0023] Figure 7 A schematic diagram of the structure of the circularly polarized antenna module provided in the embodiments of this application. Figure 2 . Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the specific technical solutions of the invention will be further described in detail below with reference to the accompanying drawings of the embodiments of this application. The following embodiments are used to illustrate the embodiments of this application, but are not intended to limit the scope of the embodiments of this application.
[0025] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.
[0026] In the following description, the terms "first, second, third" are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.
[0027] In this document, when a layer / component is referred to as being "above" another layer / component, the layer / component may be directly above the other layer / component, or there may be an intermediate layer / component between them. Furthermore, in one orientation, a layer / component is "above" another layer / component; when the orientation is reversed, the layer / component may be "below" the other layer / component.
[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which embodiments of this application belong. The terminology used herein is for descriptive purposes only and is not intended to limit the scope of embodiments of this application.
[0029] This disclosure provides an embodiment of a radio frequency front-end circuit, referring to... Figure 1 and Figure 2 As shown, the radio frequency front-end circuit includes: an amplification module 10 and a circularly polarized antenna module 20.
[0030] In this embodiment of the disclosure, reference is made to Figure 1 and Figure 2 As shown, the amplification module 10 is configured to receive a first radio frequency signal RF1 from a radio frequency source and amplify the first radio frequency signal RF1 into a second radio frequency signal RF2; the circularly polarized antenna module 20, coupled to the output terminal of the amplification module 10, is configured to receive the second radio frequency signal RF2, convert the second radio frequency signal RF2 into an electromagnetic wave and transmit it.
[0031] It should be noted that, referring to Figure 1 and Figure 2 As shown, the input terminal of the amplification module 10 is the signal input terminal RFIN, which is used to receive the first radio frequency signal RF1. The amplification module 10 amplifies the first radio frequency signal RF1 to obtain the second radio frequency signal RF2, and outputs it through the output terminal of the amplification module 10. The output terminal of the amplification module 10 is coupled to the input terminal of the circularly polarized antenna module 20. After receiving the second radio frequency signal RF2, the circularly polarized antenna module 20 converts the second radio frequency signal RF2 into electromagnetic waves and transmits them.
[0032] In this embodiment of the disclosure, reference is made to Figure 2 and Figure 3 As shown in any figure, the circularly polarized antenna module 20 includes: a mismatch suppression coupler CPL1 and an antenna; wherein, the antenna can be... Figure 2 The flat panel antenna ANT1 shown can also be Figure 3 The two linearly polarized antennas shown are ANT2 and ANT3. One of the first input terminals A and B of the mismatch suppression coupler CPL1 is connected to the second RF signal output terminal RFOUT, and the other input terminal of the first input terminal A and the second input terminal B of the mismatch suppression coupler CPL1 is connected to the ground terminal. The first output terminal C and the second output terminal D of the mismatch suppression coupler CPL1 are connected to the antenna.
[0033] It should be noted that, referring to Figure 2 and Figure 3As shown in any figure, the mismatch suppression coupler CPL1 can be a 90° coupler, capable of distributing the input signal to the first output terminal C and the second output terminal D of the mismatch suppression coupler CPL1, with a fixed phase difference of 90° between the signals at the first output terminal C and the second output terminal D of the mismatch suppression coupler CPL1. Terminal A or B of the mismatch suppression coupler CPL1 can be used as an input terminal, depending on which input terminal of the mismatch suppression coupler CPL1 is connected to the second RF signal output terminal RFOUT. For example, when terminal A of the mismatch suppression coupler CPL1 is connected to the second RF signal output terminal RFOUT, terminal B of the mismatch suppression coupler CPL1 is connected to the ground terminal. In this case, terminal A of the mismatch suppression coupler CPL1 serves as the input terminal, and terminal B of the mismatch suppression coupler CPL1 serves as the isolation terminal. Conversely, when terminal B of the mismatch suppression coupler CPL1 is connected to the second RF signal output terminal RFOUT, terminal A of the mismatch suppression coupler CPL1 is connected to the ground terminal. In this case, terminal B of the mismatch suppression coupler CPL1 serves as the input terminal, and terminal A of the mismatch suppression coupler CPL1 serves as the isolation terminal. Terminals C and D of the mismatch suppression coupler CPL1 are the through terminal and the coupling terminal, respectively.
[0034] It should also be noted that, referring to Figure 2 and Figure 3 As shown in any figure, antenna mismatch generates reflected power. This reflected power flows back through the through-hole and coupling ends into the mismatch suppression coupler CPL1. The reflected power then flows to the isolation end of the mismatch suppression coupler CPL1 and is absorbed and dissipated by the connected second adjustment circuit 22. Therefore, the mismatch suppression coupler CPL1 effectively suppresses the effects of antenna mismatch.
[0035] Understandably, referring to Figure 2 and Figure 3 As shown in any figure, this circuit amplifies the received first RF signal RF1 into a second RF signal RF2, and outputs the second RF signal RF2 to the input of the mismatch suppression coupler CPL1. The CPL1 splits the second RF signal RF2 into two signals, which are then transmitted to the antenna. The antenna converts the second RF signal RF2 into electromagnetic waves and transmits them. Compared with a traditional single-ended amplifier, the amplification module 10 not only significantly improves the output power through the power combining mechanism of the coupler, but also suppresses the adverse effects of antenna mismatch through the coupler. Simultaneously, the mismatch suppression coupler CPL1 connected to the output of the amplification module 10 can absorb reflected power, further suppressing the effects of antenna mismatch, improving reliability, and solving problems such as oscillation and burnout of the RF power amplifier caused by impedance mismatch in traditional designs.
[0036] In some embodiments of this disclosure, Figure 4 Schematic diagram of the structure of circularly polarized antenna module 20 Figure 1The antenna is a flat panel antenna ANT1.
[0037] refer to Figure 4 To suppress the coupling line E of the mismatch coupler CPL1, a two-layer structure can be adopted, wherein... Figure 5 It shows Figure 4 The upper layer wiring structure of the coupling line E, Figure 6 It shows Figure 4 The underlying routing structure of the coupling line E. Combined with... Figure 4 , Figure 5 and Figure 6 As shown, the coupling lines E of the mismatch suppression coupler CPL1 have a double-layer structure and are interconnected; the upper and lower layer wirings are symmetrical to each other. The coupling lines E include: a first coupling line 31 and a second coupling line 32; the first coupling line 31 is divided into two segments, namely a first input segment 311 and a first output segment 312; the second coupling line 32 is divided into two segments, namely a second input segment 321 and a second output segment 322.
[0038] It should be noted that, referring to Figure 4 , Figure 5 and Figure 6 As shown, in the lower layer routing, the end of the first input segment 311 near the edge is connected to the first input terminal A of the mismatch suppression coupler CPL1, the end of the first input segment 311 near the center is connected to the end of the first output segment 312 near the center of the upper layer routing, and the end of the first output segment 312 near the edge is connected to the first output terminal C of the mismatch suppression coupler CPL1; in the upper layer routing, the end of the second input segment 321 near the edge is connected to the second input terminal B of the mismatch suppression coupler CPL1, the end of the second input segment 321 near the center is connected to the end of the second output segment 322 near the center of the lower layer routing, and the end of the second output segment 322 near the edge is connected to the second output terminal D of the mismatch suppression coupler CPL1.
[0039] It should also be noted that, referring to Figure 2 and Figure 3 As shown, the double-layer wrapping design of the coupling line E of the mismatch suppression coupler CPL1 can be used to connect either the planar antenna ANT1 or two orthogonal linearly polarized antennas (ANT2, ANT3). The double-layer wrapping design of the coupling line E reduces the footprint of the mismatch suppression coupler CPL1, achieving a miniaturized design that makes it suitable for modern satellite communication terminal equipment operating in complex environments.
[0040] In some embodiments of this disclosure, reference is made to Figure 2 and Figure 3As shown in any figure, the circularly polarized antenna module 20 further includes: a first single-pole double-throw switch SPDT1 and a second single-pole double-throw switch SPDT2; the common terminal of the first single-pole double-throw switch SPDT1 is connected to the first input terminal A of the mismatch suppression coupler CPL1, the first throw point of the first single-pole double-throw switch SPDT1 is connected to the second radio frequency signal output terminal RFOUT, and the second throw point of the first single-pole double-throw switch SPDT1 is connected to the ground terminal; the common terminal of the second single-pole double-throw switch SPDT2 is connected to the first input terminal B of the mismatch suppression coupler CPL1, and the first throw point of the second single-pole double-throw switch SPDT2 is connected to the ground terminal; The second RF signal output terminal RFOUT is connected to the ground terminal; the second throw point of the second single-pole double-throw switch SPDT2 is connected to the ground terminal; when the common terminal of the first single-pole double-throw switch SPDT1 is connected to the first throw point of the first single-pole double-throw switch SPDT1, the common terminal of the second single-pole double-throw switch SPDT2 is connected to the second throw point of the second single-pole double-throw switch SPDT2; when the common terminal of the first single-pole double-throw switch SPDT1 is connected to the second throw point of the first single-pole double-throw switch SPDT1, the common terminal of the second single-pole double-throw switch SPDT2 is connected to the first throw point of the second single-pole double-throw switch SPDT2.
[0041] Among them, continue to refer to Figure 2 and Figure 3 As shown in any figure, when the circularly polarized antenna module 20 needs to receive a right-hand circularly polarized signal, the common terminal of the first single-pole double-throw switch SPDT1 is connected to the first throw point of the first single-pole double-throw switch SPDT1, and the common terminal of the second single-pole double-throw switch SPDT2 is connected to the second throw point of the second single-pole double-throw switch SPDT2. When the circularly polarized antenna module 20 needs to receive a left-hand circularly polarized signal, the common terminal of the second single-pole double-throw switch SPDT2 is connected to the first throw point of the second single-pole double-throw switch SPDT2, and the common terminal of the first single-pole double-throw switch SPDT1 is connected to the second throw point of the first single-pole double-throw switch SPDT1.
[0042] It should be noted that in practical use, the polarization directions of the transmitting and receiving ends may be mismatched due to equipment differences, installation errors, or link changes. By switching between left-hand and right-hand circular polarization, the polarization direction can be flexibly adjusted to avoid signal attenuation caused by polarization mismatch, significantly improving the power efficiency and stability of the communication link, and also enhancing anti-interference capabilities.
[0043] In some embodiments of this disclosure, reference is made to Figure 2 As shown, the antenna includes: a planar antenna ANT1; and a first output terminal A and a second output terminal B of a mismatch suppression coupler CPL1, which are respectively connected to the two feed points of the planar antenna ANT1.
[0044] It should be noted that, referring to Figure 2As shown, the planar antenna ANT1 includes a double-fed radiating element. A double-fed structure refers to having two independent feed points on the same double-fed radiating element. This double-fed structure is formed by designing two independent feed points at the input port of the double-fed radiating element of the planar antenna ANT1. The mismatch suppression coupler CPL1 and the planar antenna ANT1 work together to generate a circularly polarized wave. Switching between left-hand and right-hand circularly polarized waves is achieved by switching between the first single-pole double-throw switch SPDT1 and the second single-pole double-throw switch SPDT2. The double-fed structure, through the two feed points on the planar antenna ANT1, in conjunction with the first output terminal A and the second output terminal B of the mismatch suppression coupler CPL1, can generate a circularly polarized wave with extremely low axial ratio and high purity. This reduces the impact of environmental factors on system stability and significantly improves reliability in complex application environments.
[0045] In some embodiments of this disclosure, Figure 3 This is a circuit diagram of the radio frequency front-end circuit. Figure 7 Schematic diagram of the structure of the circularly polarized antenna module 20 for the radio frequency front-end circuit. Figure 2 Combining Figure 3 and Figure 7 As shown, the antenna includes: two linearly polarized antennas (ANT2, ANT3); the first output terminal A and the second output terminal B of the mismatch suppression coupler CPL1 are respectively connected to the feed points of the two linearly polarized antennas (ANT2, ANT3).
[0046] In some embodiments of this disclosure, reference is made to Figure 3 and Figure 7 As shown, the two linearly polarized antennas (ANT2, ANT3) are orthogonally arranged; the first output terminal C and the second output terminal D of the mismatch suppression coupler CPL1 output two orthogonal signals with a phase difference of 90°.
[0047] It should be noted that, referring to Figure 3 and Figure 7As shown, an orthogonal dual-polarized antenna is an antenna capable of simultaneously generating (or receiving) two orthogonal linearly polarized signals. It comprises two linearly polarized antennas (ANT2, ANT3), each including a linearly polarized radiating element. These two antennas (ANT2, ANT3) are orthogonally arranged and each has an independent feed point. By orthogonally arranging the two antennas (ANT2, ANT3) and connecting their respective feed points to the first output terminal A and the second output terminal B of the mismatch suppression coupler CPL1, an orthogonal dual-polarized antenna is formed. After being fed 90° by the mismatch suppression coupler CPL1, the two linearly polarized antennas (ANT2, ANT3) achieve circular polarization, generating either left-hand or right-hand circularly polarized waves. Switching between left-hand and right-hand circularly polarized waves is achieved by switching between the first single-pole double-throw switch SPDT1 and the second single-pole double-throw switch SPDT2. The two linearly polarized antennas (ANT2, ANT3) of the orthogonal dual-polarized antenna are independent of each other, with extremely high port isolation, which significantly reduces inter-channel interference, effectively combats multipath fading, and improves link reliability.
[0048] In some embodiments of this disclosure, reference is made to Figure 2 and Figure 3 As shown in any figure, the circularly polarized antenna module 20 further includes: a first adjustment circuit 21 and a second adjustment circuit 22; when the common terminal of the first single-pole double-throw switch SPDT1 is connected to the second throw point of the first single-pole double-throw switch SPDT1, it is connected to the ground terminal through the first adjustment circuit 21; when the common terminal of the second single-pole double-throw switch SPDT2 is connected to the second throw point of the second single-pole double-throw switch SPDT2, it is connected to the ground terminal through the second adjustment circuit 22.
[0049] In some embodiments of this disclosure, reference is made to Figure 2 and Figure 3 As shown in either figure, the first adjustment circuit 21 and the second adjustment circuit 22 include: a resistor and a capacitor; the resistor and capacitor are connected in series, or the resistor and capacitor are connected in parallel; the values of the capacitor and the resistor are adjustable.
[0050] It should be noted that, referring to Figure 2 and Figure 3 As shown in any figure, when the antenna is mismatched, the first adjustment circuit 21 and the second adjustment circuit 22, which are connected to the isolation terminal of the mismatch suppression coupler CPL1, maximize the absorption of reflected power by adjusting the matching impedance. At the same time, the bandwidth can also be adjusted by adjusting the size of the capacitor and the resistor.
[0051] In some embodiments of this disclosure, reference is made to Figure 2 and Figure 3As shown in any figure, the amplification module 10 includes: an input coupler CPL1, a first power amplifier PA_M, a second power amplifier PA_A, and an output coupler CPL2; the first input terminal A of the input coupler CPL1 receives a first radio frequency signal RF1, the second input terminal B of the input coupler CPL1 is connected to the ground terminal, the first output terminal C of the input coupler CPL1 is connected to the input terminal of the first power amplifier PA_M, and the second output terminal D of the input coupler CPL1 is connected to the input terminal of the second power amplifier PA_A; the output terminal of the first power amplifier PA_M is connected to the first input terminal A of the output coupler CPL2, the output terminal of the second power amplifier PA_A is connected to the second input terminal B of the output coupler CPL2, the first output terminal C of the output coupler CPL2 outputs a second radio frequency signal RF2, and the second output terminal D of the output coupler CPL2 is connected to the ground terminal.
[0052] It should be noted that, referring to Figure 2 and Figure 3 As shown in any figure, the amplification module 10 connects the first radio frequency signal RF1 to the first input terminal A of the input coupler CPL1. The input coupler CPL1 splits the first radio frequency signal RF1 into two signals, which are output from the first output terminal C and the second output terminal D of the input coupler CPL1, respectively. These two signals are respectively input to the first power amplifier PA_M and the second power amplifier PA_A to amplify the signals. The amplified two signals are then input to the first input terminal A and the second input terminal B of the output coupler CPL2, respectively. The output coupler CPL2 combines the amplified two signals into a second radio frequency signal RF2, which is output from the first output terminal C of the output coupler CPL2.
[0053] In some embodiments of this disclosure, reference is made to Figure 2 and Figure 3 As shown in any figure, the second input terminal B of the input coupler CPL1 and the second output terminal D of the output coupler CPL2 are connected to the ground terminal through the impedance-adjustable load circuit 11.
[0054] It should be noted that, referring to Figure 2 and Figure 3 As shown in any figure, the load circuit 11 can be a resistor, or a capacitor and a resistor in series, and the values of the resistor and capacitor are adjustable. By adjusting the size of the load circuit 11, the bandwidth range can be widened to cover the 1.6-2.0GHz wideband required by multiple systems such as Beidou and StarNet. It can also control the amplifier's operating frequency, efficiency, and power output to ensure optimal performance across the entire L / S (long wave / short wave) band operating range.
[0055] Understandably, referring to Figure 2 and Figure 3As shown in any figure, during power amplification, when a common-mode signal (such as electromagnetic interference, power supply noise, etc.) is present in the input, since the first power amplifier PA_M and the second power amplifier PA_A are identical, the common-mode signal remains in phase after amplification. Through the combining effect of the output coupler CPL2, the common-mode component is significantly attenuated due to phase cancellation. This mechanism makes the amplifier's anti-interference capability against common-mode interference such as environmental noise and power supply fluctuations far superior to that of a single-ended power amplifier. Furthermore, if one of the power amplifiers fails, the amplification module 10 can still be used, offering higher reliability compared to using a single power amplifier. When the output terminal of the output coupler CPL2 receives a reflected signal, the reflected power is directed to the load circuit 11 at the isolation terminal of the output coupler CPL2 and consumed, further protecting the first power amplifier PA_M and the second power amplifier PA_A.
[0056] It should be understood that in the various embodiments of this application, the sequence numbers of the above-described processes do not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The sequence numbers of the above-described embodiments of this application are merely for description and do not represent the superiority or inferiority of the embodiments. It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.
[0057] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The methods disclosed in the several method embodiments provided in this application can be arbitrarily combined to obtain new method embodiments without conflict. The features disclosed in the several product embodiments provided in this application can be arbitrarily combined to obtain new product embodiments without conflict. The features disclosed in the several method or device embodiments provided in this application can be arbitrarily combined to obtain new method or device embodiments without conflict.
[0058] The above are merely specific implementations of the embodiments of this application, but the protection scope of the embodiments of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the embodiments of this application should be covered within the protection scope of the embodiments of this application.
Claims
1. A radio frequency front-end circuit, characterized in that, The radio frequency front-end circuit includes: An amplification module is configured to receive a first radio frequency signal from a radio frequency source and amplify the first radio frequency signal into a second radio frequency signal. A circularly polarized antenna module, coupled to the output of the amplification module, is configured to receive the second radio frequency signal, convert the second radio frequency signal into electromagnetic waves, and transmit them. The circularly polarized antenna module includes: a mismatch suppression coupler and an antenna; one of the first and second input terminals of the mismatch suppression coupler is connected to the output terminal of the amplification module, the other input terminal of the first and second input terminals of the mismatch suppression coupler is connected to a ground terminal, and the first and second output terminals of the mismatch suppression coupler are connected to the antenna. The circularly polarized antenna module further includes: a first single-pole double-throw switch and a second single-pole double-throw switch; The common terminal of the first single-pole double-throw switch is connected to the first input terminal of the mismatch suppression coupler, the first throw point of the first single-pole double-throw switch is connected to the second radio frequency signal output terminal, and the second throw point of the first single-pole double-throw switch is connected to the ground terminal; the common terminal of the second single-pole double-throw switch is connected to the second input terminal of the mismatch suppression coupler, the first throw point of the second single-pole double-throw switch is connected to the second radio frequency signal output terminal, and the second throw point of the second single-pole double-throw switch is connected to the ground terminal. When the common terminal of the first single-pole double-throw switch is connected to the first throw point of the first single-pole double-throw switch, the common terminal of the second single-pole double-throw switch is connected to the second throw point of the second single-pole double-throw switch; When the common terminal of the first single-pole double-throw switch is connected to the second throw point of the first single-pole double-throw switch, the common terminal of the second single-pole double-throw switch is connected to the first throw point of the second single-pole double-throw switch; The circularly polarized antenna module further includes: a first adjustment circuit and a second adjustment circuit; When the common terminal of the first single-pole double-throw switch is connected to the second throw point of the first single-pole double-throw switch, it is connected to the ground terminal through the first adjustment circuit; When the common terminal of the second single-pole double-throw switch is connected to the second throw point of the second single-pole double-throw switch, it is connected to the ground terminal through the second adjustment circuit.
2. The radio frequency front-end circuit according to claim 1, characterized in that, The two coupling lines of the mismatch suppression coupler have a double-layer structure and are wired around each other; the upper layer wiring and the lower layer wiring are symmetrical to each other.
3. The radio frequency front-end circuit according to claim 1, characterized in that, The antenna includes: a flat panel antenna; The first and second output terminals of the mismatch suppression coupler are respectively connected to the two feed points of the planar antenna.
4. The radio frequency front-end circuit according to claim 1, characterized in that, The antenna includes: two linearly polarized antennas; The first and second output terminals of the mismatch suppression coupler are respectively connected to the feed points of the two linearly polarized antennas.
5. The radio frequency front-end circuit according to claim 4, characterized in that, The two linearly polarized antennas are orthogonally arranged; the first and second output terminals of the mismatch suppression coupler output two orthogonal signals with a phase difference of 90°.
6. The radio frequency front-end circuit according to claim 1, characterized in that, The first adjustment circuit and the second adjustment circuit each include a resistor and a capacitor; the resistor and the capacitor are connected in series, or the resistor and the capacitor are connected in parallel; the values of the capacitor and the resistor are adjustable.
7. The radio frequency front-end circuit according to claim 1, characterized in that, The amplification module includes: an input coupler, a first power amplifier, a second power amplifier, and an output coupler; The first input terminal of the input coupler receives a first radio frequency signal, the second input terminal of the input coupler is connected to the ground terminal, the first output terminal of the input coupler is connected to the input terminal of the first power amplifier, and the second output terminal of the input coupler is connected to the input terminal of the second power amplifier. The output terminal of the first power amplifier is connected to the first input terminal of the output coupler, the output terminal of the second power amplifier is connected to the second input terminal of the output coupler, the first output terminal of the output coupler outputs a second radio frequency signal, and the second output terminal of the output coupler is connected to the ground terminal.
8. The radio frequency front-end circuit according to claim 7, characterized in that, The second input terminal of the input coupler and the second output terminal of the output coupler are connected to the ground terminal through an impedance-adjustable load circuit.