Radio frequency front-end module, radio frequency processing circuit and communication equipment

Abstract

The invention provides a radio frequency front-end module, a radio frequency processing circuit and a communication device, the radio frequency front-end module comprises a first filter circuit and a second filter circuit, the second filter circuit comprises a filter assembly and a radio frequency load element, the filter assembly is connected between the input end of the first filter circuit and the first end of the radio frequency load element, and the first end of the radio frequency load element is connected with the second filter circuit. The second end of the radio frequency load element is connected with the grounding end. Thus, the radio frequency load element can control the impedance in a certain frequency band, so that the impedance in the frequency band can be matched with the in-band impedance of the output end side of the filtering assembly, and then the passband frequency band of the filtering assembly is transmitted to the grounding end, thereby eliminating the reflection at the first transmission end. When the two filter circuits are arranged in the receiving path and the high-power signal in the transmitting path is leaked into the receiving path, the input end of the first filter circuit in the receiving path can be prevented from generating reflection, so that the receiving performance of the radio frequency front-end module is improved.

Description

Technical Field

[0001] This application relates to the field of terminal technology, and in particular to a radio frequency front-end module, radio frequency processing circuit and communication equipment. Background Technology

[0002] Communication equipment generally includes a baseband circuit and a radio frequency (RF) system. Processing received RF signals or transmitting RF signals is achieved through the RF system, which comprises an RF transceiver unit, an RF front-end module, and an antenna device. The baseband circuit is coupled to the RF transceiver unit, which is coupled to the RF front-end module, which is also coupled to the antenna device. The RF front-end module includes a transmit path and a receive path. The transmit path can be used to transmit RF signals of various frequency bands to the antenna device. The receive path can be used to receive RF signals of various frequency bands from the antenna device.

[0003] However, in the RF front-end module, high-power signals in the transmitting path may partially leak into the receiving path, causing reflections at the input of the filter in the receiving path. This can trigger a nonlinear response in the receiving path, leading to performance degradation and making it impossible to effectively process the RF signals received from the antenna device. Summary of the Invention

[0004] This application provides a radio frequency front-end module, a radio frequency processing circuit, and a communication device to prevent high-power signals in the transmitting path of the radio frequency front-end module from leaking into the receiving path and causing reflection in the receiving path, thereby improving the receiving performance of the radio frequency front-end module.

[0005] In a first aspect, embodiments of this application provide a radio frequency (RF) front-end module, comprising: a first filter circuit, the input terminal of which is connected to a first transmission terminal in the RF front-end module, and the output terminal of which is connected to a second transmission terminal in the RF front-end module; and a second filter circuit, comprising a filter component and an RF load element, the filter component being connected between the input terminal of the first filter circuit and a first terminal of the RF load element, and the second terminal of the RF load element being connected to a ground terminal. Thus, the RF load element can control the impedance within a certain frequency band, allowing the impedance within that frequency band to match the in-band impedance at the output terminal of the filter component. When impedance matching occurs, the passband frequency of the filter component can be transmitted to the ground terminal, thereby eliminating reflection at the first transmission terminal. When both filter circuits are located in the receiving path, and a high-power signal in the transmitting path leaks into the receiving path, reflection at the input terminal of the first filter circuit in the receiving path can be avoided, thereby preventing the generation of a nonlinear response in the receiving path and improving the receiving performance of the RF front-end module.

[0006] In this embodiment, the first signal path can be a receiving path and the second signal path can be a transmitting path; alternatively, when there are multiple receiving paths, the first signal path can be one of the receiving paths and the second signal path can be another receiving path; alternatively, the first signal path can be a transmitting path and the second signal path can be a receiving path; or alternatively, when there are multiple transmitting paths, the first signal path can be one of the transmitting paths and the second signal path can be another transmitting path. Whenever a reflected signal appears at the input of the first filter circuit, a second filter circuit can be added to absorb the stopband frequency of the first filter circuit, eliminate reflections at the input of the first filter circuit, and improve the performance of the transmitting and receiving paths. Furthermore, the first signal path can also include a third transmission terminal, with the first transmission terminal located between the third transmission terminal and the second transmission terminal, and the first filter circuit located between the first transmission terminal and the second transmission terminal. In this case, the first signal path can also include other structures well-known to those skilled in the art, such as, but not limited to, amplifiers and duplexers, and these devices can be located between the third transmission terminal and the first transmission terminal. Specific devices can be added according to actual needs, and no specific limitations are made here.

[0007] Furthermore, by setting a second filter circuit, the difference between the in-band impedance and the out-of-band impedance of the first transmission end can be reduced or made approximately the same. This avoids the generation of reflected signals when out-of-band frequencies are incident on the input end of the first filter circuit due to a large difference between the in-band and out-of-band impedances. This prevents the reflected signals from causing intermodulation distortion in the first signal path and degrading its performance, thereby improving the performance of the first signal path. It also allows for control of the in-band and out-of-band impedances. For example, the in-band impedance can be, but is not limited to, 50Ω, while the out-of-band impedance can be, but is not limited to, 40Ω, 45Ω, 50Ω, 55Ω, or other resistance values, and can be set according to actual needs; no specific limitation is made here.

[0008] Optionally, the passband frequency of the first filter circuit is different from that of the filter component. This allows the filter component to absorb the reflected signal at the input end of the first filter circuit, which helps to create a reflection-free state at the first transmission end and improves the performance of the RF front-end module.

[0009] Optionally, the second filter circuit includes a filter component and an RF load element. The filter component is connected between the input terminal of the first filter circuit and the first terminal of the RF load element, and the second terminal of the RF load element is connected to the ground terminal. In this way, the RF load element can provide a matching impedance for the filter component, so that the passband frequency band of the filter component can be transmitted to the ground terminal through the RF load element, thereby absorbing the reflected signal at the input terminal of the first filter circuit to eliminate reflection.

[0010] Alternatively, the implementation of the filtering component can include the following:

[0011] The first type: The filtering component includes a first trapezoidal filter, in which the cascade order of the acoustic resonators is no greater than 20. Further, the cascade order of the acoustic resonators in the first trapezoidal filter is no greater than 10, such as, but not limited to, other values ​​like 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. The specific value can be set according to actual needs and is not limited here.

[0012] The second type: The filtering component includes at least one DMS filter, and the number of at least one DMS filter is no more than 10. Further, the number of at least one DMS filter is no more than 5, for example, but not limited to, cascade orders of 1, 2, 3, 4, 5, etc., which can be set according to actual needs and are not limited here. Furthermore, when multiple DMS filters are set, they are connected in parallel.

[0013] The third type: The filtering component includes a first trapezoidal filter and at least one DMS filter. The number of at least one DMS filter is no more than 10, and the cascade order of the acoustic resonators in the first trapezoidal filter is no more than 20. Further, the number of at least one DMS filter is no more than 5, such as, but not limited to, 1, 2, 3, 4, 5, etc.; further, the cascade order of the acoustic resonators in the first trapezoidal filter is no more than 10, such as, but not limited to, cascade orders of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc., which can be set according to actual needs and are not limited here. Furthermore, when multiple DMS filters are set, each DMS filter is connected in parallel and then in series with the first trapezoidal filter.

[0014] Of course, in addition to the structures described above, the filtering component can also be implemented using other devices known to those skilled in the art that can perform filtering functions, such as, but not limited to, dielectric filters, MEMS resonators, etc., which are not limited here.

[0015] Based on the specific structure of the filtering components described above, the filter can also adopt a similar configuration. For example, the filter may include at least one of a second trapezoidal filter and a DMS filter. When including both a second trapezoidal filter and a DMS filter, the cascade order of the acoustic resonators in the second trapezoidal filter is no greater than 10, the number of DMS filters is no greater than 20, and each DMS filter is connected in parallel and then in series with the second trapezoidal filter. Furthermore, when the filtering components include a first trapezoidal filter and the filter includes a second trapezoidal filter, the cascade order of the acoustic resonators in the second trapezoidal filter is greater than the cascade order of the acoustic resonators in the first trapezoidal filter. In other words, if the filter includes a second trapezoidal filter, it can be considered that the first filtering circuit includes a second trapezoidal filter, the cascade order of the acoustic resonators in the first trapezoidal filter is the first order, and the cascade order of the acoustic resonators in the second trapezoidal filter is the second order, where the second order is greater than the first order. In this way, the first filter circuit can achieve out-of-band suppression and low in-band insertion loss. Since the purpose of the filter component is to absorb signals in the out-of-band frequency band of the first filter circuit, the requirement for in-band insertion loss is low. As a result, the cascade order of the acoustic resonator in the first trapezoidal filter can be set to be smaller, thereby reducing the manufacturing cost of the RF front-end module.

[0016] Optionally, a filter component and an RF load element may be provided, and the filter component and the RF load element are connected in series between the first transmission end and the ground end.

[0017] Alternatively, the second filtering circuit includes multiple filtering components and at least one RF load element. That is, multiple filtering components and at least one RF load element can be provided, with each RF load element connected to at least a portion of the filtering components. Different filtering components have different passband frequencies. The second filtering circuit also includes an impedance matching network located between the RF load element and the connected multiple filtering components. When at least one RF load element is provided, the number of filtering components can be greater than the number of RF load elements, ensuring that each RF load element is connected to at least one filtering component. Furthermore, the passband signal extracted by each filtering component can be transmitted to the ground terminal through the connected RF load element. This reduces the number of RF load elements to some extent, thereby lowering the manufacturing cost of the RF front-end module. Moreover, when the impedance matching network is located between the RF load element and the connected multiple filtering components, the impedance of the RF load element can be matched with the in-band impedance of the output terminals of each connected filtering component. This prevents interference between the passband frequencies of different filtering components when passing through the RF load element, allowing the passband frequencies of multiple filtering components to be transmitted to the ground terminal through the same RF load element, achieving effective absorption of reflected signals. Alternatively, when multiple RF load elements are provided, the number of filter components can be equal to the number of RF load elements, so that each filter component is connected to one RF load element. In other words, the corresponding filter component and RF load element are connected in series to form an absorption branch, and each absorption branch is connected in parallel between the first transmission terminal and the ground terminal. This allows each filter component to be matched with an RF load element, thereby ensuring that the passband signal extracted by each filter component can be transmitted to the ground terminal, avoiding transmission obstruction due to impedance mismatch of the RF load elements, further eliminating reflection at the first transmission terminal, and further improving the performance of the first signal path.

[0018] Optionally, the first filtering circuit includes at least one of a bandpass filter, a low-pass filter, and a high-pass filter; the passband frequency bands of the filtering components, the bandpass frequency bands of the bandpass filter, the low-pass filter, and the high-pass filter are all different. Thus, the relevant frequency band signals can be extracted through the first filtering circuit, achieving the function of the first filtering circuit.

[0019] The first filtering circuit includes filters, which can be any one of the following: bandpass filter, low-pass filter, high-pass filter, and stopband filter. The passband frequency of this filter is the passband frequency of the first filtering circuit. There can be one filter; or, there can be N filters, where N is an integer greater than 1. In this case, the multiple filters can be combined in the following ways: if the filter is a bandpass filter, then there are N bandpass filters, meaning the first filtering circuit includes multiple bandpass filters; or, if the filter is a bandpass filter or a low-pass filter, then there are N-1 bandpass filters and one low-pass filter; or, if the filter is a bandpass filter or a high-pass filter, then there are N-1 bandpass filters and one high-pass filter.

[0020] Furthermore, taking an example where multiple filters are used, each being a bandpass filter, the first filtering circuit includes multiple bandpass filters. When there is only one second transmission terminal, the bandpass filters are connected in parallel, and the passband frequencies of different bandpass filters are different. In this way, the first filtering circuit can transmit signals across multiple frequency bands, and the second filtering circuit can absorb the out-of-band frequencies of the first filter film, thereby eliminating reflected signals at the first transmission terminal and improving the performance of the first signal path. This also reduces the number of second transmission terminals, simplifying the structure of the RF front-end module and lowering its manufacturing cost. Alternatively, when there are multiple second transmission terminals, and the number of second transmission terminals is less than the number of bandpass filters, some bandpass filters are connected to the same second transmission terminal. This not only enables signal transmission but also reduces the number of second transmission terminals to some extent, lowering the manufacturing cost of the RF front-end module. Or, when there are multiple second transmission terminals, and the number of second transmission terminals equals the number of bandpass filters, different bandpass filters are connected to different second transmission terminals, allowing signals from different filters to be output through different ports, achieving precise signal transmission.

[0021] Secondly, embodiments of this application also provide a radio frequency (RF) processing circuit, which may include: an RF circuit and an RF front-end module as described in the first aspect and any of the embodiments described above, wherein the RF circuit is connected to the RF front-end module. Thus, based on the improved performance of the RF front-end module, the performance of the RF processing circuit will also be improved.

[0022] It should be understood that since the principle of this RF processing circuit in solving the problem is similar to that of the aforementioned RF front-end module in solving the problem, the implementation and technical effects of this RF processing circuit can be found in the implementation and technical effects of the aforementioned RF front-end module, and the repetitions will not be repeated.

[0023] Thirdly, embodiments of this application also provide a communication device, which may include: a baseband circuit, an antenna device, and a radio frequency processing circuit as described in the second aspect and any of the embodiments described above; the radio frequency processing circuit is connected to both the baseband circuit and the antenna device. Thus, by improving the performance of the radio frequency processing circuit, the performance of the communication device will also be improved.

[0024] It should be understood that since the principle by which this communication device solves the problem is similar to that of the aforementioned radio frequency processing circuit, the implementation and technical effects of this communication device can be found in the implementation and technical effects of the aforementioned radio frequency processing circuit, and the repetitions will not be repeated. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application;

[0026] Figure 2 This is a schematic diagram of the structure of a radio frequency front-end module in the prior art;

[0027] Figure 3 This is a schematic diagram of the structure of a radio frequency front-end module provided in an embodiment of this application;

[0028] Figure 4 This is a schematic diagram of another radio frequency front-end module provided in an embodiment of this application;

[0029] Figure 5 This is a schematic diagram of another radio frequency front-end module provided in the embodiments of this application;

[0030] Figure 6 This is a schematic diagram of another radio frequency front-end module provided in an embodiment of this application;

[0031] Figure 7 This is a schematic diagram of the structure of a surface acoustic wave resonator provided in an embodiment of this application;

[0032] Figure 8 This is a schematic diagram of the structure of a bulk acoustic resonator provided in an embodiment of this application;

[0033] Figure 9 This is a schematic diagram of another radio frequency front-end module provided in an embodiment of this application;

[0034] Figure 10 This is a schematic diagram of another radio frequency front-end module provided in an embodiment of this application;

[0035] Figure 11 This is a schematic diagram of another radio frequency front-end module provided in an embodiment of this application.

[0036] Figure label:

[0037] 100-Baseband circuit, 200-RF system, 210-RF transceiver unit, 220-RF front-end module, 221-Transmit path, 221a-First filter, 221b-Power amplifier, 222-Receive path, 222a-Duplexer, 222b-Low noise amplifier, 222c-Matching network, 222d-Second filter, 230-Antenna device, 10-First filter circuit, 10a-Filter, 11-Bandpass filter, 20-Second filter circuit, 21-Filter assembly, 22-RF load element, A0-Acoustic resonator, A1-DMS filter, A2-First trapezoidal filter, A2'-Second trapezoidal filter, A3-Absorption branch, L1-First inductor, L2-Second inductor, L3-Third inductor, GND-Ground terminal, N1-First transmission terminal, N2-Second transmission terminal, N3-Third transmission terminal. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the application will now be described in further detail with reference to the accompanying drawings.

[0039] It should be noted that the same reference numerals in the accompanying drawings of this application denote the same or similar structures, and therefore repeated descriptions of them will be omitted. Terms expressing position and direction described in this application are illustrative based on the accompanying drawings, but may be modified as needed, and all such modifications are included within the scope of protection of this application. The accompanying drawings of this application are for illustrating relative positional relationships only and do not represent actual scale.

[0040] The phrase "structure A is connected to structure B" as described in this application means that structure A and structure B can be directly connected, or indirectly connected; where direct connection means that structure A and structure B are in contact and connected, and indirect connection means that structure A is connected to structure B through structure C. Similarly, the phrase "structure A is coupled to structure B" as described in this application means that structure A and structure B can be directly coupled, or indirectly coupled; where direct coupling means that structure A and structure B are in contact and coupled, and indirect coupling means that structure A is coupled to structure B through structure C. The specific configuration can be determined according to actual needs, and this application does not impose any specific limitations.

[0041] To facilitate understanding of the technical solutions provided in the embodiments of this application, the application scenarios will be explained first below.

[0042] The technical solutions provided in this application can be widely applied to various communication devices with radio frequency (RF) functions. For example, these communication devices can be cellular phones, smartphones, handheld wireless devices with or without telephone functionality, wireless tablets, base stations, routers, satellites, etc. Base stations can include various forms of macro base stations, micro base stations, relay stations, access points, or remote radio units. It should be noted that the RF front-end module proposed in this application is intended for application, including but not limited to, in these and any other suitable types of communication devices with RF functions.

[0043] Figure 1 This is a schematic diagram of a communication device provided in an embodiment of this application. (Refer to...) Figure 1 As shown, the communication device may include a baseband circuit 100 and a radio frequency (RF) system 200, with the RF system 200 coupled to the baseband circuit 100. During signal transmission, the baseband circuit 100 can modulate the low-frequency baseband signal to be transmitted into a mid-to-high-frequency digital signal and transmit the mid-to-high-frequency digital signal to the RF system 200; during signal reception, the baseband circuit 100 can demodulate the high-frequency electromagnetic wave signal from the RF system 200 into a low-frequency baseband signal.

[0044] The radio frequency (RF) system 200 includes an RF transceiver unit 210, an RF front-end module 220, and an antenna device 230. A baseband circuit 100 is coupled to the RF transceiver unit 210, which is coupled to the RF front-end module 220. The RF front-end module 220 is also coupled to the antenna device 230. The RF front-end module 220 includes a transmit path 221 and a receive path 222. The number of transmit paths 221 and receive paths 222 can be one or more. The transmit path 221 can be used to transmit RF signals of various frequency bands to the antenna device 230. The receive path 222 can be used to receive RF signals of various frequency bands from the antenna device 230. It should be understood that the RF transceiver unit 210 and the RF front-end module 220 can be considered as an RF processing circuit. Figure 1 The radio frequency processing circuit is not shown in the figure. It is connected to the baseband circuit 100 and the antenna device 230 respectively.

[0045] During signal transmission, the RF transceiver unit 210 modulates the mid-to-high frequency digital signal from the baseband circuit 100 into a high-frequency electromagnetic wave signal (i.e., an RF signal). The RF front-end module 220 performs power amplification and filtering on this high-frequency electromagnetic wave signal, and then radiates the amplified and filtered signal through the antenna device 230. During signal reception, the RF front-end module 220 performs filtering and low-noise amplification on the high-frequency electromagnetic wave signal received by the antenna device 230. The RF transceiver unit 210 demodulates the filtered and low-noise amplified high-frequency electromagnetic wave signal into a mid-to-high frequency digital signal, and then sends the mid-to-high frequency digital signal to the baseband circuit 100.

[0046] Both the transmitting path 221 and the receiving path 222 may include filters, and may also include, but are not limited to, other devices such as power amplifiers, RF switches, and low-noise amplifiers. The specific design can be tailored to actual needs and is not specifically limited here. (Refer to...) Figure 2 As shown, the transmit path 221 includes a power amplifier 221b, a first filter 221a, and a duplexer 222a coupled in sequence. The receive path 222 includes a duplexer 222a, a low-noise amplifier 222b, a matching network 222c, and a second filter 222d coupled in sequence. The duplexer 222a in the transmit path 221 and the receive path 222 can be multiplexed, that is, a duplexer 222a is provided so that the first filter 221a is connected to the antenna device 230 through the duplexer 222a, and the low-noise amplifier 222b is connected to the antenna device 230. The acoustic amplifier 222b is also connected to the antenna device 230 via the duplexer 222a; the output of the second filter 222d is connected to the RF transceiver unit 210; in the receiving path 222, the RF signal received by the antenna device 230 is output to the low-noise amplifier 222b via the duplexer 222a, so that the low-noise amplifier 222b amplifies the RF signal, and after passing through the matching network 222c, it is filtered by the second filter 222d to remove unwanted frequency band signals before being output to the RF transceiver unit 210. However, the high-power signal in the transmitting path 221 will also partially leak into the receiving path 222, and after passing through the low-noise amplifier 222b and the matching network 222c, it will be reflected at the input of the second filter 222d, thereby exciting the nonlinear response of the receiving path 222, causing the performance of the receiving path 222 to deteriorate, and making it impossible to effectively process the RF signal received by the antenna device 230.

[0047] To address this issue, this application provides an RF front-end module that avoids reflections at the input of a filter in the receiving path, thereby improving the performance of the receiving path. Specifically, the RF front-end module provided in this application includes: a first filter circuit, the input of which is connected to a first transmission terminal in the RF front-end module, and the output of which is connected to a second transmission terminal in the RF front-end module; and a second filter circuit, comprising a filter component and an RF load element, the filter component being connected between the input of the first filter circuit and a first terminal of the RF load element, and the second terminal of the RF load element being connected to a ground terminal. Thus, the RF load element can control the impedance within a certain frequency band, allowing the impedance within that band to match the in-band impedance at the output of the filter component. When impedance matching occurs, the passband frequency of the filter component can be transmitted to the ground terminal, thereby eliminating reflections at the first transmission terminal. When two filter circuits are located in the receiving path, and a high-power signal in the transmitting path leaks into the receiving path, reflections at the input of the first filter circuit in the receiving path can be avoided, thus preventing nonlinear responses from being generated in the receiving path and improving the receiving performance of the RF front-end module.

[0048] The radio frequency front-end module will be introduced below with reference to specific embodiments.

[0049] Figure 3 This is a schematic diagram of the structure of a radio frequency front-end module provided in an embodiment of this application, with reference to... Figure 3 As shown, the RF front-end module may include: a first signal path and a second signal path. The connection point between the first signal path and the second signal path can be denoted as the first transmission terminal N1. The first signal path also has a second transmission terminal N2. The first transmission terminal N1 and the second transmission terminal N2 are two different ports within the first signal path. Figure 3In this circuit, the first signal path includes a branch connecting the first transmission terminal N1 and the second transmission terminal N2, and a branch connecting the first transmission terminal N1 and the ground terminal GND. Therefore, the first signal path can be considered as a path including these two branches. At this time, the RF front-end module may include: a first filter circuit 10, whose input terminal is connected to the first transmission terminal N1, and whose output terminal is connected to the second transmission terminal N2 of the first signal path. That is, the first filter circuit 10 is located in the branch connecting the first transmission terminal N1 and the second transmission terminal N2. The first filter circuit 10 is used to: extract the first frequency band signal from the RF signal input from the first transmission terminal N1 and output it to the second transmission terminal N2 of the first signal path; and a second filter circuit 20, whose input terminal is connected to the first transmission terminal N1, and whose output terminal is connected to the ground terminal GND. That is, the second filter circuit 20 is located in the branch connecting the first transmission terminal N1 and the second transmission terminal N2. In the branch between N1 and the ground terminal GND, both the first filter circuit 10 and the second filter circuit 20 are in the first signal path. The second filter circuit 20 is used to extract the third frequency band signal from the radio frequency signal and transmit it to the ground terminal GND. The radio frequency signal at the first transmission terminal N1 may include a first frequency band signal and a second frequency band signal coupled to the first transmission terminal N1. The frequency band of the second frequency band signal is different from that of the first frequency band signal, and the frequency band of the third frequency band signal overlaps with that of the second frequency band signal. Furthermore, the second frequency band signal coupled to the first transmission terminal N1 may be coupled to the first transmission terminal N1 from the second signal path or from the first signal path. In other words, the frequency band of the first frequency band signal can be considered as the passband of the first filter circuit 10, and the frequency band of the third frequency band signal can be considered as the passband of the second filter circuit 20. Therefore, the passband of the second filter circuit 20 is located outside the passband of the first filter circuit 10 (i.e., outside the band or stopband). Furthermore, the frequency band of the third frequency band signal can be exactly the same as or partially the same as the frequency band of the second frequency band signal. In this case, the second filter circuit 20 can transmit at least a portion of the second frequency band signal coupled to the first transmission terminal N1 to the ground terminal GND, improving the signal quality of the second frequency band signal. The reflection generated at the first transmission terminal N1; in other words, the second filter circuit 20 can absorb the signal in the passband outside the frequency band of the first filter circuit 10, so that the reflected signal at the first transmission terminal N1 is absorbed, which is conducive to forming a reflection-free state at the first transmission terminal N1. When the first signal path is the receiving path, the second signal path is the transmitting path, and the high-power signal in the transmitting path leaks into the receiving path, the reflection generated at the input terminal of the first filter circuit 10 in the receiving path can be avoided, thereby avoiding the excitation of nonlinear response in the receiving path, thus improving the receiving performance of the RF front-end module.

[0050] It should be understood that in this embodiment, the first signal path can be a receiving path and the second signal path can be a transmitting path; or, when there are multiple receiving paths, the first signal path can be one of the receiving paths and the second signal path can be another receiving path; or, the first signal path can be a transmitting path and the second signal path can be a receiving path; or, when there are multiple transmitting paths, the first signal path can be one of the transmitting paths and the second signal path can be another transmitting path; as long as a reflected signal appears at the input of the first filter circuit 10, a second filter circuit 20 can be added to absorb the stopband frequency band of the first filter circuit 10, eliminate the reflection at the input of the first filter circuit 10, and improve the performance of the transmitting path and the receiving path. Furthermore, the first signal path may also include a third transmission terminal N3, with the first transmission terminal N1 located between the third transmission terminal N3 and the second transmission terminal N2, and the first filter circuit 10 located between the first transmission terminal N1 and the second transmission terminal N2. In this case, the first signal path may also include other structures known to those skilled in the art, such as, but not limited to, amplifiers, duplexers, etc., and these devices may be located between the third transmission terminal N3 and the first transmission terminal N1. Specifically, relevant devices may be added according to actual needs, and no specific limitations are made here.

[0051] Furthermore, by setting the second filter circuit 20, the difference between the in-band impedance and the out-of-band impedance of the first transmission terminal N1 can be reduced or made approximately the same. This avoids the generation of reflected signals when the out-of-band frequency band is incident on the input terminal of the first filter circuit 10 due to a large difference between the out-of-band impedance and the in-band impedance. This prevents the reflected signals from causing intermodulation distortion in the first signal path and degrading the performance of the first signal path, thereby improving the performance of the first signal path. It also enables the control of the in-band impedance and the out-of-band impedance. For example, the in-band impedance can be, but is not limited to, 50Ω, and the out-of-band impedance can be, but is not limited to, other resistance values ​​such as 40Ω, 45Ω, 50Ω, and 55Ω. Other resistance values ​​can also be set according to actual needs, and are not specifically limited here.

[0052] For example, the first filtering circuit 10 includes a filter, through which a first frequency band signal can be extracted, thus realizing the function of the first filtering circuit 10. Specifically, the filter can be any one of a bandpass filter 11, a low-pass filter, a high-pass filter, and a stopband filter; in this case, the passband frequency band of the filter is the passband frequency band of the first filtering circuit 10. It should be understood that... Figure 3 The example shown is a bandpass filter 11, but this does not mean that the filter can only be a bandpass filter 11.

[0053] The second filtering circuit 20 may include a filtering component 21 and an RF load element 22. The filtering component 21 is connected between the first transmission terminal N1 (and the input terminal of the first filtering circuit 10) and the first terminal of the RF load element 22. The second terminal of the RF load element 22 is connected to the ground terminal GND. The filtering component 21 is used to extract the third frequency band signal from the RF signal and transmit it to the RF load element 22. Therefore, the passband of the filtering component 21 is different from the passband of the first filtering circuit 10. The RF load element 22 is used to transmit the third frequency band signal to the ground terminal GND. One filtering component 21 and one RF load element 22 may be provided. Thus, the filtering component 21 extracts the third frequency band signal, and the RF load element 22 provides a matching impedance to the filtering component 21 so that the third frequency band signal passing through the filtering component 21 can be transmitted to the ground terminal GND, thereby absorbing the third frequency band signal and eliminating reflection at the first transmission terminal N1.

[0054] It is worth noting that the RF load element 22 can be, but is not limited to, an RF load patch or an RF load head, and the RF load element 22 is different from a regular resistor. The RF load element 22 can control the impedance within a certain frequency band (such as the frequency band where the third frequency band signal is located), so that the impedance within this frequency band can be matched with the in-band impedance of the output terminal of the filter component 21. Only when the impedance is matched can the passband of the filter component 21 be transmitted to the ground terminal GND, thereby achieving the absorption of the third frequency band signal and eliminating the reflection at the first transmission terminal N1. If the RF load element 22 is replaced with a regular resistor, since a regular resistor does not have the specification of impedance within a certain frequency band, it cannot match the in-band impedance of the output terminal of the filter component 21. As a result, the resistor cannot transmit the passband of the filter component 21 to the ground terminal GND, but will reflect the passband back to the filter component 21, which may eventually lead to reflection to the input terminal of the first filter circuit 10, thus failing to achieve the purpose of eliminating the reflected signal at the input terminal of the first filter circuit 10. Similarly, if a regular resistor is placed between the input terminal of the first filter circuit 10 and the input terminal of the filter component 21, the resistor cannot match the in-band impedance of the input terminal of the first filter circuit 10. Therefore, the reflected signal cannot be transmitted to the filter component 21, and thus the reflected signal at the input terminal of the first filter circuit 10 cannot be eliminated. Therefore, by setting the filter component 21 and the RF load element 22, the function of the second filter circuit 20 can be realized, achieving the absorption of the third frequency band signal and eliminating the reflection at the first transmission terminal N1.

[0055] For ease of description, the passband of the filter is referred to as the first passband, and the passband of the filter component 21 is referred to as the second passband. The first passband can be smaller than the second passband, or the first passband can be larger than the second passband. In other words, the frequency band of the third frequency band signal can be smaller than the frequency band of the first frequency band signal, or the frequency band of the third frequency band signal can be larger than the frequency band of the first frequency band signal. The specific settings can be made according to actual needs and are not limited here.

[0056] For example, the filter component 21 may include the following configuration forms:

[0057] The filtering component 21 may include a first trapezoidal filter A2, and the cascade order of the acoustic resonator A0 in the first trapezoidal filter A2 is no greater than 20. Further, the cascade order of the acoustic resonator A0 in the first trapezoidal filter A2 is no greater than 10, such as, but not limited to, other values ​​such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. The specific value can be set according to actual needs and is not limited here. Figure 4 In the first trapezoidal filter A2, there are multiple acoustic resonators A0. Some of the acoustic resonators A0 are connected in series, and some are connected in parallel. The number of acoustic resonators A0 connected in series corresponds to the cascade order. Figure 4 Two acoustic resonators A0 are shown in series, so the corresponding cascade order is 2. The node between two adjacent acoustic resonators A0 in series needs to be connected to one end of the other acoustic resonator A0 to achieve the function of the filter component 21. Of course... Figure 4 This is just an example; in actual implementation, the specific cascade order is not limited to this. Figure 4 As shown in the image.

[0058] Alternatively, the filtering component 21 may include at least one DMS filter A1, and the number of DMS filters A1 may not exceed 10. Further, the number of DMS filters A1 may not exceed 5, for example, but not limited to, 1, 2, 3, 4, 5, or other values. The specific number can be set according to actual needs and is not limited here. Furthermore, when multiple DMS filters A1 are configured, they are connected in parallel. Figure 5 As shown in the figure, a DMS filter A1 is illustrated. Figure 5 This is just an example; in actual implementation, the specific number of settings is not limited to this. Figure 5 As shown in the image.

[0059] Alternatively, the filtering component 21 may include a first trapezoidal filter A2 and at least one DMS filter A1. The number of DMS filters A1 is no more than 10, and further, the number of DMS filters A1 is no more than 5, such as, but not limited to, other values ​​like 1, 2, 3, 4, 5, etc. The cascade order of the acoustic resonators in the first trapezoidal filter A2 is no more than 20, and further, the cascade order of the acoustic resonators in the first trapezoidal filter A2 is no more than 10, such as, but not limited to, other values ​​like 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. The specific settings can be configured according to actual needs and are not limited here. Furthermore, when multiple DMS filters A1 are provided, each DMS filter A1 is connected in parallel and then in series with the first trapezoidal filter A2. Figure 6 As shown in the figure, the first trapezoidal filter A2 consists of two DMS filters A1 and a cascaded acoustic resonator of order 3. Figure 6 This is just an example; in actual implementation, the specific cascade order is not limited to this. Figure 6 As shown in the image.

[0060] Of course, in addition to the structures described above, the filter component 21 can also be implemented using other devices known to those skilled in the art that can perform filtering functions, such as, but not limited to, dielectric filters, MEMS resonators, etc., which are not limited here.

[0061] Based on the specific structure of the filter component 21 described above, the filter can also adopt a similar configuration. For example, the filter may include at least one of a second trapezoidal filter A2' and a DMS filter A1. When the filter includes a second trapezoidal filter A2' and a DMS filter A1, the cascade order of the acoustic resonator A0 in the second trapezoidal filter A2' is no greater than 20, the number of DMS filters A1 is no greater than 10, and each DMS filter A1 is connected in parallel and then connected in series with the second trapezoidal filter A2'.

[0062] Furthermore, when the filter component 21 includes a first trapezoidal filter A2 and the filter includes a second trapezoidal filter A2', the cascade order of the acoustic resonators in the second trapezoidal filter A2' is greater than the cascade order of the acoustic resonators in the first trapezoidal filter A2. In other words, the filter including the second trapezoidal filter A2' can be considered as the first filter circuit 10 including the second trapezoidal filter A2', where the cascade order of the acoustic resonators in the first trapezoidal filter A2 is the first order, and the cascade order of the acoustic resonators in the second trapezoidal filter A2' is the second order, and the second order is greater than the first order. This achieves the goal of out-of-band suppression and low in-band insertion loss in the first filter circuit 10. Since the filter component 21 aims to absorb signals in the out-of-band frequency band of the first filter circuit 10, the requirement for in-band insertion loss is low, thus allowing the cascade order of the acoustic resonators in the first trapezoidal filter A2 to be set smaller, thereby reducing the manufacturing cost of the RF front-end module. For example, as... Figure 4 As shown, the filter may include a second trapezoidal filter A2', where the cascade order of the second trapezoidal filter A2' is 4, while the cascade order of the acoustic resonators in the first trapezoidal filter A2 is 2. In this case, the cascade order of the acoustic resonators in the second trapezoidal filter A2' is greater than the cascade order of the acoustic resonators in the first trapezoidal filter A2; of course, this is only an example. Figure 4 The example shown is for illustration only. The cascade order of the acoustic resonator in the trapezoidal filter of the filter and filter component 21 can be set according to actual needs and is not limited here.

[0063] In addition, see Figure 4 As shown, an impedance matching network can also be provided in the first signal path, and the impedance matching network can be located in at least one of the following positions: between the first filter circuit 10 and the first transmission terminal N1, between the first filter circuit 10 and the second transmission terminal N2, between the first transmission terminal N1 and the third transmission terminal N3, between the filter component 21 and the first transmission terminal N1, and between the filter component 21 and the RF load element 22. The impedance matching network can achieve matching of in-band impedance and out-of-band impedance. Figure 4 Only the impedance matching networks between the first filter circuit 10 and the first transmission terminal N1, the first filter circuit 10 and the second transmission terminal N2, and the first transmission terminal N1 and the third transmission terminal N3 are shown. Impedance matching networks at other locations are not shown, but this does not mean that impedance matching networks cannot be set at these locations. Of course, no impedance matching network may be set in the first signal path to meet the needs of different application scenarios; and an impedance matching network may also be set in the second signal path, but... Figure 4The structure of the second signal path is not limited to what is shown in the document. The specific structure of the second signal path can be configured according to actual needs and is not limited herein. It should be understood that the impedance matching network can be, but is not limited to, at least one of an inductor and a capacitor. The specific structure of the impedance matching network can be configured according to actual needs and is not limited herein.

[0064] The acoustic resonator can be a surface acoustic wave (SAW) resonator or a bulk acoustic wave (BAW) resonator. For SAW resonators, the specific structure can include the following:

[0065] like Figure 7 As shown in (a), this figure is a top view of a surface acoustic wave (SAW) resonator. The SAW resonator may include a piezoelectric substrate, and a first electrode and a second electrode disposed on the piezoelectric substrate. The first electrode and the second electrode form interdigitated electrodes. The first electrode can convert radio frequency signals into surface acoustic waves (e.g., ...). Figure 7 (As shown by the dashed arrow in the middle) After that, the surface acoustic wave (SAW) can propagate on the surface of the piezoelectric substrate. The second electrode can convert the SAW into a radio frequency (RF) signal and output it, thereby filtering unnecessary signals and interference and improving signal quality. It should be understood that since the RF signal is an AC signal, the first electrode can convert the RF signal into a SAW and vice versa at different times. The second electrode can do the same, and at the same time, the functions of the first and second electrodes are different. For example, when the first electrode is converting the SAW into an RF signal, the function of the second electrode is also converting the RF signal into a SAW; or, when the first electrode is converting the RF signal into a SAW, the function of the second electrode is also converting the SAW into an RF signal, thus achieving the filtering function and also enabling the transmission of the RF signal.

[0066] Or, such as Figure 7 As shown in (b) of the figure, this figure is a cross-sectional view of a surface acoustic wave (SAW) resonator. The SAW resonator may include: a substrate, and a Bragg reflector layer, a piezoelectric layer, and an electrode layer sequentially disposed on the substrate. The electrode layer includes a first electrode and a second electrode. Figure 7 In (b), the first and second electrodes are not shown. The Bragg reflector layer includes a low acoustic impedance layer and a high acoustic impedance layer stacked together, with the low acoustic impedance layer disposed between the high acoustic impedance layer and the substrate. Figure 7 The internal structure of the Bragg reflector is not shown in (b). This structure can not only filter out unwanted signals, but also reflect the leakage wave incident on the Bragg reflector, thereby improving the quality factor of the surface acoustic wave resonator.

[0067] Of course, the above only uses two structures as examples to illustrate the structure of surface acoustic wave (SAW) resonators. However, this application does not limit the structure of SAW resonators; they can be any structure well-known to those skilled in the art. Furthermore, the DMS filter is essentially a type of SAW filter, and its specific structure is basically the same as that of the SAW resonator. The difference lies in that the DMS filter has more interfaces compared to the SAW resonator. The specific structure of the DMS filter can be configured according to actual needs and is not limited here.

[0068] For bulk acoustic resonators, the specific structures can include the following:

[0069] like Figure 8 As shown in (a), the bulk acoustic wave resonator may include: a substrate, and a functional layer, a first electrode, a piezoelectric layer, and a second electrode sequentially disposed on the substrate. A cavity is provided in the functional layer. The functions of the first and second electrodes are similar to those in the surface acoustic wave resonator described above, and will not be detailed here. Since the first and second electrodes are located on opposite sides of the piezoelectric layer, the generated sound waves pass through the piezoelectric layer, forming bulk acoustic waves. The bulk acoustic waves are as follows: Figure 8 As shown by the dashed arrow in (a); and the cavity can have a reflective effect, thereby improving the quality factor of the bulk acoustic resonator.

[0070] Or, such as Figure 8 As shown in (b), the bulk acoustic wave resonator may include: a substrate, and a Bragg reflector layer, a first electrode, a piezoelectric layer, and a second electrode sequentially disposed on the substrate. The Bragg reflector layer includes: a plurality of low acoustic impedance layers and a plurality of high acoustic impedance layers stacked together, with the low acoustic impedance layers and high acoustic impedance layers alternately disposed. Figure 8 The internal structure of the Bragg reflector is not shown in (b). The leakage wave incident on the Bragg reflector is reflected by the Bragg reflector, thereby improving the quality factor of the surface acoustic wave resonator.

[0071] Of course, the above are just two examples to illustrate the structure of a bulk acoustic resonator. However, the structure of the bulk acoustic resonator is not limited in this application. The bulk acoustic resonator can be any structure known to those skilled in the art.

[0072] Figure 9 This is a schematic diagram of another radio frequency front-end module provided in an embodiment of this application, referring to... Figure 9 As shown, the RF front-end module in this embodiment is similar to that in the aforementioned embodiments. Figures 3 to 8The structures of the RF front-end modules described are basically the same, with the following differences: multiple filter components 21 are provided, and the passband frequency bands of different filter components 21 are different; at least one RF load element 22 is provided, and the number of filter components 21 is greater than the number of RF load elements 22, so that each RF load element 22 is connected to at least one filter component 21. That is, some filter components 21 share a RF load element 22 to transmit signals to the ground terminal GND, and some filter components 21 transmit signals to the ground terminal GND through other RF load elements 22. At this time, for multiple filter components 21 connected to the same RF load element 22, an impedance matching network can be set between the RF load element 22 and the multiple filter components 11 connected to it. Through this impedance matching network, the impedance of the RF load element 22 can be matched with the in-band impedance of the output terminal side of each filter component 11 connected to it, avoiding mutual interference of the passband frequency bands of different filter components 11 when passing through the RF load element 22, so that the passband frequency bands of multiple filter components 11 can be transmitted to the ground terminal GND through the same RF load element 22, and the reflected signal can be effectively absorbed. Furthermore, it can reduce the number of RF load components 22 to some extent, thereby reducing the manufacturing cost of the RF front-end module. Among these, Figure 9 This example illustrates the configuration of three filter components 21 and two RF load elements 22. The filter components 21 and RF load elements 22 are not limited to these configurations. Figure 9 As shown, the specific settings can be adjusted according to actual needs and are not limited here.

[0073] It should be understood that the RF front-end module in this embodiment is different from that in the aforementioned embodiments. Figures 3 to 8 The structural similarities of the RF front-end modules described in the preceding embodiments can be found in the relevant descriptions, and the repeated parts will not be repeated here.

[0074] Figure 10 This is a schematic diagram of another radio frequency front-end module provided in an embodiment of this application, referring to... Figure 10 As shown, the RF front-end module in this embodiment is similar to that in the aforementioned embodiments. Figures 3 to 8The RF front-end modules described herein have a basically the same structure, with the following differences: multiple filter components 21 are provided, each with a different passband frequency band; multiple RF load elements 22 are provided, and the number of filter components 21 is equal to the number of RF load elements 22, so that each filter component 21 is connected to one RF load element 22. In other words, the corresponding filter component 21 and RF load element 22 are connected in series to form an absorption branch A3, and each absorption branch A3 is connected in parallel between the first transmission terminal N1 and the ground terminal GND. This allows each filter component 21 to be matched with one RF load element 22, and thus the impedance of each RF load element 22 can be matched with the in-band impedance of the output terminal of the corresponding filter component 21. This ensures that the passband signal extracted by each filter component 21 can be transmitted to the ground terminal GND, avoiding transmission obstruction due to impedance mismatch of the RF load element 22, thereby further eliminating reflection at the first transmission terminal N1 and further improving the performance of the signal path.

[0075] It should be understood that the RF front-end module in this embodiment is different from that in the aforementioned embodiments. Figures 3 to 8 The structural similarities of the RF front-end modules described in the preceding embodiments can be found in the relevant descriptions, and the repeated parts will not be repeated here.

[0076] Figure 11 This is a schematic diagram of another radio frequency front-end module provided in an embodiment of this application, referring to... Figure 11 As shown, the RF front-end module in this embodiment is similar to that in the aforementioned embodiments. Figures 3 to 10 The structures of any of the RF front-end modules described herein are basically the same, with the following differences: the first filter circuit 10 includes multiple filters 10a. For example, see [link to example]. Figure 11 As shown, the passband frequency bands of different filters 10a are different, and the passband frequency bands of each filter 10a are different from the frequency bands of the second frequency band signal. In this way, the first filter circuit 10 can transmit signals of multiple frequency bands, and the second filter circuit 20 can absorb the out-of-band frequency bands of the first filter film, thereby eliminating the reflected signal at the first transmission end N1 and improving the performance of the first signal path.

[0077] Furthermore, the second transmission terminal N2 of the first signal path can be configured to have one, such as... Figure 11As shown in (a), in this case, each filter 10a is connected in parallel and then connected to the second transmission terminal N2, so that the signals output by each filter 10a are all output through the same port (i.e., N2). Alternatively, multiple second transmission terminals N2 are provided in the first signal path, and the number of second transmission terminals N2 is less than the number of filters 10a (not shown). In this case, each second transmission terminal N2 is connected to at least one filter 10a, so that the signals output by some filters 10a are output through different ports. Or, multiple second transmission terminals N2 are provided in the first signal path, and the number of second transmission terminals N2 is equal to the number of filters 10a, such as... Figure 11 As shown in (b), different filters 10a are connected to different second transmission terminals N2, so that the signals output by different filters 10a are output through different ports.

[0078] Furthermore, when multiple filters 10a are provided, they will have multiple passband frequency bands. For ease of description, the passband frequency band of filter 10a is referred to as the first passband frequency band. At this time, the frequency band of the second frequency band signal can be located between two adjacent first passband frequency bands, so that the nonlinear intermodulation component can avoid falling within the first passband frequency band, thereby avoiding the excitation of the nonlinear response of the first signal path, reducing interference, and improving the performance of the first signal path.

[0079] It is worth noting that when there are N filters 10, and N is an integer greater than 1, the types of filters 10a can include the following: filter 10a is a bandpass filter, in which case there are N bandpass filters; or, filter 10a is a bandpass filter or a low-pass filter, in which case there are N-1 bandpass filters and one low-pass filter; or, filter 10a is a bandpass filter or a high-pass filter, in which case there are N-1 bandpass filters and one high-pass filter.

[0080] It should be understood that the RF front-end module in this embodiment is different from that in the aforementioned embodiments. Figures 3 to 10 The structural similarities of the RF front-end modules described in the preceding embodiments can be found in the relevant descriptions, and the repeated parts will not be repeated here.

[0081] In summary, the first filtering circuit can include at least one of a bandpass filter, a low-pass filter, and a high-pass filter, and the passband frequencies of the filtering components, the bandpass filters, the low-pass filters, and the high-pass filters are all different, thereby eliminating reflected signals at the first transmission end and improving the performance of the first signal path. The specific structures included in the first filtering circuit can be configured according to actual needs and are not specifically limited here. For the number and configuration of the filtering components and RF load elements in the second filtering circuit, please refer to the description in the above embodiments. Furthermore, the configuration of the first and second filtering circuits is not mutually restrictive and can be freely combined to meet the design needs of different application scenarios, thus broadening the application range of the RF front-end module.

[0082] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of the embodiments of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.

Claims

1. A radio frequency front-end module, characterized in that, include: A first filtering circuit, wherein the input terminal of the first filtering circuit is connected to the first transmission terminal in the RF front-end module, and the output terminal of the first filtering circuit is connected to the second transmission terminal in the RF front-end module; The second filtering circuit includes a filtering component and an RF load element. The filtering component is connected between the input terminal of the first filtering circuit and the first terminal of the RF load element, and the second terminal of the RF load element is connected to the ground terminal.

2. The radio frequency front-end module as described in claim 1, characterized in that, The passband frequency band of the first filter circuit is different from that of the filter component.

3. The radio frequency front-end module as described in claim 1 or 2, characterized in that, The second filtering circuit includes a plurality of the filtering components and at least one of the radio frequency load elements, each of the radio frequency load elements being connected to at least a portion of the filtering components, and the passband frequency bands of the different filtering components being different; The second filter circuit further includes an impedance matching network, which is disposed between the RF load element and the plurality of connected filter components.

4. The radio frequency front-end module as described in any one of claims 1-3, characterized in that, The filtering component includes a first trapezoidal filter, wherein the cascade order of the acoustic resonators in the first trapezoidal filter is no greater than 20.

5. The radio frequency front-end module as described in any one of claims 1-3, characterized in that, The filtering component includes at least one DMS filter, and the at least one DMS filter is arranged in parallel, and the number of the at least one DMS filter is no more than 10.

6. The radio frequency front-end module as described in any one of claims 1-3, characterized in that, The filtering component includes a first trapezoidal filter and at least one DMS filter, wherein the at least one DMS filter is connected in parallel and then in series with the first trapezoidal filter; the number of the at least one DMS filter is no more than 10, and the cascade order of the acoustic resonators in the first trapezoidal filter is no more than 20.

7. The radio frequency front-end module as described in claim 4 or 6, characterized in that, The cascade order of the acoustic resonators in the first trapezoidal filter is the first order; The first filter circuit includes a second trapezoidal filter, wherein the cascade order of the acoustic resonators in the second trapezoidal filter is a second order, which is greater than the first order.

8. The radio frequency front-end module as described in any one of claims 1-7, characterized in that, The first filtering circuit includes at least one of a bandpass filter, a low-pass filter, and a high-pass filter; The passband frequency bands of the filtering component, the bandpass filter, the low-pass filter, and the high-pass filter are all different.

9. The radio frequency front-end module as described in claim 8, characterized in that, The first filtering circuit includes multiple bandpass filters, and the passband frequency bands of the different bandpass filters are different.

10. A radio frequency processing circuit, characterized in that, include: The radio frequency circuit, and the radio frequency front-end module as described in any one of claims 1-9, wherein the radio frequency circuit is connected to the radio frequency front-end module.

11. A communication device, characterized in that, include: Baseband circuit, antenna device, and radio frequency processing circuit as described in claim 10; The radio frequency processing circuit is connected to the baseband circuit and the antenna device, respectively.

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