Radio frequency isolation module and communication system

Abstract

The present application provides a radio frequency isolation module and a communication system, which can support the output of multi-band signals and has isolation capabilities to prevent reflected signals from affecting a power amplifier circuit or power amplifier module. The radio frequency isolation module has lower insertion loss and reduces intermodulation distortion. The radio frequency isolation module may include a dividing circuit, an isolation circuit, and a combining circuit. The isolation circuit includes at least one isolation branch. The dividing circuit includes an input end and N output ends. The N output ends correspond one-to-one to the N frequency bands, with one output end coupled to one isolation branch, and each output end configured to output a signal in the frequency band corresponding to the coupled isolation branch. Each isolation branch is configured to transmit a signal provided by one output end of the dividing circuit coupled to the combining circuit and to prevent a signal generated in the combining circuit from being transmitted to the input end coupled to the isolation branch. The combining circuit is coupled to an antenna and configured to combine signals transmitted over the isolation branches in the isolation circuit.

Description

[Technical Field]

[0001] The present application relates to the field of wireless communication technologies, and in particular to radio frequency isolation modules and communication systems. [Background technology]

[0002] Currently, a remote radio unit generally supports a radio frequency signal of one frequency band. The remote radio unit includes a power amplifier module and an isolator. The power amplifier module performs power amplification processing on the radio frequency signal. The function of the isolator is generally to transmit the power-amplified signal to an antenna and isolate the reflected signal generated at the antenna to prevent the reflected signal from affecting the power amplifier module.

[0003] If the remote radio unit supports radio frequency signals of multiple frequency bands, the power amplifier module in the remote radio unit also needs to support more frequency bands and has the ability to output higher power, and the isolator in the remote radio unit also needs to operate at higher power and can support multiple frequency bands.

[0004] The performance parameters of an isolator generally include insertion loss and intermodulation distortion. The insertion loss of an isolator generally refers to the signal loss created when the isolator is inserted into a communication system and can be understood as signal attenuation. When two or more signals with different frequencies are applied to the same nonlinear circuit, the signals are intermodulated to create a signal with a new frequency. If the new frequency falls exactly within the bandwidth of the channel in which the receiver operates, interference to the receiver occurs. This interference is commonly referred to as intermodulation distortion.

[0005] However, an isolator that can support multiple frequency bands has a relatively large insertion loss and a relatively large intermodulation distortion, which causes a relatively large insertion loss and a relatively large intermodulation distortion of a remote radio unit that supports multiple frequency bands, and affects the quality of a transmission signal of a transmitter in a communication system, making it difficult to apply an isolator to a communication system. Summary of the Invention

[0006] The embodiments of the present application provide a radio frequency isolation module and a communication system, which can support the output of multi-band signals and have isolation capabilities to prevent reflected signals from affecting a power amplifier circuit or a power amplifier module. The radio frequency isolation module has lower insertion loss and reduces intermodulation distortion.

[0007] According to a first aspect, the present application provides a radio frequency isolation module configured to transmit a target radio frequency signal provided by a power amplification module to an antenna. The operating frequency band of the radio frequency isolation module covers the operating frequency band of the power amplification module, and the operating frequency band of the radio frequency isolation module includes N frequency bands, where N is an integer greater than 1. The radio frequency isolation module may include a dividing circuit, an isolation circuit, and a combining circuit. The isolation circuit includes at least one isolation branch. The divider circuit includes an input terminal and N output terminals. The input terminal is coupled to the power amplifier module and configured to receive a target radio frequency signal. The target radio frequency signal includes signals in S frequency bands, where S is an integer equal to or less than N. The N output terminals correspond one-to-one to the N frequency bands. One output terminal is coupled to one isolation branch, and each output terminal is configured to output a signal in a frequency band corresponding to the coupled isolation branch. The divider circuit is configured to divide the target radio frequency signal into signals in each frequency band included in the S frequency bands and output the signals using the output terminal corresponding to each frequency band. Each isolation branch is coupled to a combiner circuit and configured to transmit a signal provided by one output terminal of the divider circuit coupled to the combiner circuit and prevent a signal generated in the combiner circuit from being transmitted to the input terminal coupled to the isolation branch. The combiner circuit is coupled to an antenna and configured to combine signals transmitted by the isolation branches in the isolation circuit and output a combined signal to the antenna.

[0008] In this embodiment of the present application, the dividing circuit in the radio frequency isolation module can divide the target radio frequency signal and output S signals by using S output terminals of the dividing circuit. The S signals correspond one-to-one to the S frequency bands, and one output terminal of the dividing circuit outputs a signal including one frequency band. The S signals can be separately sent to the combining circuit by using coupled isolation branches. In this way, the requirements for the operating frequency band of the isolation branches in the isolation circuit can be reduced, and isolators or circulators with lower insertion loss and smaller intermodulation distortion can be used, and each isolation branch further has the function of separating the signals generated in the combining circuit to protect the power amplification module.

[0009] In a possible design, the isolation circuit includes N isolation branches, each of which corresponds one-to-one with the N output terminals. The operating frequency band of an isolation branch covers a frequency band corresponding to the output terminal coupled to the isolation branch. In such a design, the operating frequency band of each isolation branch includes one frequency band, which reduces the requirements of the isolation branch for the operating frequency band. Therefore, the isolation branch may use an isolator or circulator with lower insertion loss and smaller intermodulation distortion.

[0010] In a possible design, the isolation circuit includes M isolation branches, where M is an integer less than N, and one of the M isolation branches is coupled to at least one of the output ends, and the operating frequency bands of the isolation branches cover frequency bands corresponding to at least one of the output ends coupled to the isolation branches. In such a design, the operating frequency band of each isolation branch includes a frequency band corresponding to the output end coupled to the isolation branch, and the operating frequency band of each isolation branch may not need to include N frequency bands. This reduces the requirements of the isolation branches for the operating frequency band, and therefore the isolation branches may use isolators or circulators with lower insertion loss and smaller intermodulation distortion.

[0011] In any one of the above possible designs, the splitting circuit may include at least one splitter. In any one of the above possible designs, the isolation branch may include a circulator.

[0012] In any one of the above possible designs, the combining circuit may include a multi-band combiner. Optionally, the combining circuit may further include at least one filter, where the at least one filter may correspond one-to-one with the at least one isolation branch. Each isolation branch may be coupled to the multi-band combiner using a corresponding filter. The operating frequency band of each filter covers the operating frequency band of the isolation branch coupled to the filter. Each filter may be configured to perform filtering on the signal provided by the coupled isolation branch, for example, to filter out noise signals.

[0013] Optionally, the operating frequency band of the radio frequency isolation module may cover at least two of the following frequency bands: a 758 MHz to 960 MHz frequency band, a 1.8 GHz frequency band, a 2.1 GHz frequency band, or a 2.6 GHz frequency band. The operating frequency band of the radio frequency isolation module is not particularly limited in this application and is described only as an example for the purposes of explanation herein.

[0014] According to a second aspect, an embodiment of the present application provides a communication system including a transmitter, a power amplifier module, and a radio frequency isolation module provided in any one of the first aspect and possible designs thereof. The transmitter is configured to generate a first radio frequency signal. The power amplifier module is separately coupled to the transmitter and the radio frequency isolation module and configured to amplify the first radio frequency signal to obtain a second radio frequency signal and output the second radio frequency signal to the radio frequency isolation module. The radio frequency isolation module is configured to be coupled to an antenna, and the radio frequency isolation module is configured to transmit the second radio frequency signal to the antenna.

[0015] In this embodiment of the present application, the radio frequency isolation module in the communication system has lower insertion loss and reduces intermodulation distortion. Furthermore, the radio frequency isolation module is disposed between the antenna and the power amplifier module, and separates the antenna from the power amplifier module to prevent signals at the antenna from affecting the power amplifier module.

[0016] In one possible design, the power amplification module includes a power splitter, multiple power amplification circuits, and a first combiner. The power splitter is coupled to each power amplification circuit and configured to perform power allocation on the first radio frequency signal and output a third radio frequency signal to each power amplification circuit, where the sum of the powers of all the third radio frequency signals output by the power splitter is equal to the power of the first radio frequency signal. Each power amplification circuit is coupled to the first combiner and configured to perform power amplification on the received third radio frequency signal and output the third radio frequency signal to the combiner. The combiner is coupled to the radio frequency isolation module and configured to combine the signals separately output by the multiple power amplification circuits to obtain a second radio frequency signal and output the second radio frequency signal to the radio frequency isolation module.

[0017] In such a design, multiple power amplifier circuits are arranged in a power amplifier module, and the signals output by the multiple power amplifier circuits are combined into a single path signal by using a first combiner for output, so that the power amplifier module can output a single path radio frequency signal with higher power, thereby improving the power of the radio frequency signal transmitted by the communication system. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a diagram of an application scenario for a remote radio unit. [Figure 2] FIG. 2 is a diagram of the structure of a remote radio unit. [Figure 3] 1 is a diagram of the structure of a communication system according to an embodiment of the present application; [Figure 4] 1 is a diagram of a specific structure of a power amplifier module. [Figure 5] FIG. 1 is a diagram of a structure of a radio frequency isolation module according to an embodiment of the present application. [Figure 6A] FIG. 1 is a diagram of the structure of a split circuit. [Figure 6B]1 is a diagram of a particular structure of a splitter circuit; [Figure 6C] FIG. 10 is a diagram of a specific structure of another split circuit. [Figure 6D] FIG. 10 is a diagram of a specific structure of yet another split circuit. [Figure 7A] 1 is a diagram of a specific structure of a radio frequency isolation module according to an embodiment of the present application; [Figure 7B] FIG. 10 is a diagram of a specific structure of another radio frequency isolation module according to an embodiment of the present application. [Figure 8] FIG. 10 is a diagram of yet another radio frequency isolation module structure according to an embodiment of the present application. [Figure 9] FIG. 10 is a diagram of yet another radio frequency isolation module structure according to an embodiment of the present application. [Figure 10] FIG. 10 is a diagram of yet another radio frequency isolation module structure according to an embodiment of the present application. [Figure 11] FIG. 10 is a diagram of yet another radio frequency isolation module structure according to an embodiment of the present application. [Figure 12] FIG. 10 is a diagram of yet another radio frequency isolation module structure according to an embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0019] In the embodiment of the present application, "or" represents an association relationship between related objects, and indicates that two relationships may exist. For example, A or B may represent the following cases: only A exists, and only B exists, and A and B may be singular or plural.

[0020] The term "coupled" in this application represents a connection relationship between two objects, and may represent two connection relationships. For example, "A is connected to B" may represent the following cases: A is directly connected to B, and A is connected to B through C.

[0021] In the embodiments of this application, terms such as "for example," "in some embodiments," "in another embodiment," and the like are used to denote providing an example, illustration, or explanation. Any embodiment or design solution described in this application as an "example" should not be described as being preferred or having more advantages than another embodiment or design solution. Rather, the use of the word "example" is intended to present concepts in a particular way.

[0022] An "antenna" in embodiments of the present application may include any suitable configuration, structure, and / or arrangement of one or more antenna elements, components, units, assemblies, and / or arrays. In some examples, an antenna may implement transmit and receive functions using separate transmit and receive antenna elements.

[0023] A "power amplification module" in embodiments of the present application may include any suitable configuration, structure, and / or arrangement of one or more power amplifiers, components, units, and assemblies.

[0024] A "transmitter" in embodiments of the present application may include appropriate components for implementing a transmitting function, such as a digital signal processor, a digital-to-analog converter, a baseband filter, a radio frequency (RF) modulator, a filter, an RF separator, and a switch. In some examples, a "transmitter" may be a transceiver, and may separately implement a transmitting function and a receiving function. A transceiver may include appropriate components for implementing a transmitting function, such as a digital signal processor, a digital-to-analog converter, a baseband filter, a radio frequency (RF) modulator, a filter, an RF separator, and a switch. Alternatively, a transceiver may include appropriate components for implementing a receiving function, such as a combiner, a demodulator, a baseband filter, and an analog-to-digital converter.

[0025] In embodiments of the present application, a "path" may be a transmission path, a transmission channel, or a transmission line. A "path" may refer to a transmission path, a transmission channel, or a transmission line. Multiple "paths" may refer to multiple transmission paths, transmission channels, or transmission lines. A signal of a "path" may refer to a signal transmitted through a transmission path, a transmission channel, or a transmission line. In some examples, "D" sending a signal of a path may mean that the signal sent by "D" is transmitted through a transmission path, a transmission channel, or a transmission line. "D" receiving a signal of a path may mean that "D" can receive a signal transmitted through a transmission path, a transmission channel, or a transmission line. "D" receiving signals of multiple paths may mean that "D" can receive signals transmitted through multiple transmission paths, transmission lines, or transmission lines.

[0026] In the embodiment of the present application, E corresponds to F one-to-one, and one E corresponds to one F, and one F corresponds to one E. It should be noted that in the embodiment of the present application, words such as "first" and "second" are not used for the purpose of distinguishing between descriptions, and cannot be understood as an indication or implication of relative importance or an indication or implication of sequence.

[0027] The radio frequency isolation module provided in the embodiments of the present application may be applied to multiple communication systems, such as a global system for mobile communications (GSM), a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) system, a general packet radio service (GPRS), a long term evolution (LTE) system, an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD), a universal mobile telecommunications system (UMTS), a worldwide interoperability for microwave access (WiMAX) communication system, or a fifth-generation (5G) mobile communication technology. It should be noted that the specific communication system is not limited in the embodiments of the present application.

[0028] In embodiments of the present application, a "frequency band" may be a frequency band divided into divided frequency bands and / or future version frequency bands. For example, a "frequency band" may be a frequency band divided according to existing cellular specifications and / or protocols (e.g., 3rd generation partnership project (3GPP) protocol or LTE protocol), or a frequency band divided according to future version cellular specifications and / or protocols, or a frequency band divided according to a wireless fidelity (Wi-Fi) protocol in a wireless local area network, or a frequency band divided according to a Bluetooth protocol.

[0029] FIG. 1 is a diagram of a communication system architecture to which an embodiment of the present application is applicable. As shown in FIG. 1, the communication system architecture may include a baseband processing unit and a remote radio unit (RRU). The baseband processing unit may be disposed in an equipment room, and the RRU may be disposed near an antenna, for example, on a communication tower where the antenna is located. The baseband processing unit, RRU, and antenna shown in FIG. 1 are only used to describe the communication system architecture by using an example and do not indicate the amount of antennas and RRUs in the communication system. Generally, the communication system may be implemented as a base station. The base station may include a base station processing unit, at least one antenna, and at least one RRU. The baseband processing unit may be connected to at least one RRU.

[0030] Existing RRUs support single-band radio frequency signals. To enable a communication system to support radio frequency signals of multiple frequency bands, at least two RRUs may be installed in the communication system, and the at least two RRUs occupy a larger space. Alternatively, at least two power amplifier modules supporting different frequency bands may be installed in a single RRU, and thus the single RRU occupies more space. Alternatively, power amplifier modules supporting multiple frequency bands may be installed in a single RRU, and have higher power. FIG. 2 is a diagram of the structure of an RRU supporting multiple frequency bands. The RRU includes a transmitter (TX), a power amplifier circuit, a radio frequency isolation module, and a filter. The transmitter may be capable of providing multi-band signals. The signal provided by the transmitter may include multiple frequency bands. For example, the signal provided by the transmitter includes a signal of a first frequency band and a second frequency band. The power amplifier circuit in the RRU may support power amplification for the multi-band signals and output the multi-band signals to an isolator. The function of an isolator is generally to send a power amplified signal to a filter and isolate reflected signals generated at the filter or antenna to prevent the reflected signals from affecting the power amplification circuitry.

[0031] In some scenarios, the first and second frequency bands may be any two of the following frequency bands: 1.8 GHz, 2.1 GHz, or 2.6 GHz. Accordingly, the isolator in the RRU must operate in a frequency band between 1805 MHz and 2690 MHz. An isolator that can support multiple frequency bands in this way is sometimes called an ultra-wideband isolator.

[0032] The performance parameters of an isolator in a communication system generally include insertion loss and intermodulation distortion. The insertion loss of an isolator generally refers to the signal loss generated when the isolator is inserted into a communication system and can be understood as signal attenuation. When two or more signals with different frequencies are applied to the same nonlinear circuit, the signals are intermodulated to generate a signal with a new frequency. If the new frequency falls exactly within the bandwidth of the channel in which the receiver operates, interference to the receiver occurs. This interference is generally called intermodulation distortion. Intermodulation distortion in a communication system also affects the quality of signals transmitted by the transmitter. The insertion loss of an isolator operating in the 1805 MHz to 2690 MHz frequency band is generally greater than 0.5 dB. An isolator has a maximum power parameter, which represents the maximum power at which a signal can be transmitted. The smaller the power of the signal transmitted by the isolator, the smaller the isolator's intermodulation distortion. When the power of a signal transmitted by an isolator in the 1805 MHz to 2690 MHz frequency band is the maximum power parameter, the intermodulation distortion of the isolator is generally greater than -60 dBc. However, in existing communication systems, the intermodulation distortion is generally required to be less than -70 dBc. In existing communication systems, the power of a signal transmitted by an isolator in the 1805 MHz to 2690 MHz frequency band must be less than the maximum power parameter of the isolator, which means that the isolator cannot operate at full power in the 1805 MHz to 2690 MHz frequency band.

[0033] To reduce the insertion loss of an RRU and improve the intermodulation distortion of the RRU, an embodiment of the present application provides a radio frequency isolation module, which can support the output of multi-band signals and has isolation capabilities to prevent reflected signals from affecting a power amplifier circuit or a power amplifier module. The radio frequency isolation module has lower insertion loss and reduces intermodulation distortion. It should be noted that the embodiment of the present application may be applied to, but is not limited to, an RRU and may further be applied to a unit in a communication system, such as an active antenna unit (AAU). Application scenarios of the radio frequency isolation module are not limited in this application. An embodiment of the present application further provides a communication system, which may include the radio frequency isolation module provided in this application. The following provides a detailed description with reference to the accompanying drawings. It should be noted that the specific frequency bands described in this application are used only as examples for explanation and are not used as specific limitations on the frequency bands applicable to the radio frequency isolation module provided in this application.

[0034] 3 is a diagram of the structure of a communication system according to an embodiment of the present application. The communication system 10 may include a transmitter 100, a power amplification module 101, and a radio frequency isolation module 102 provided in an embodiment of the present application. The transmitter 100, the power amplification module 101, and the radio frequency isolation module 102 are coupled in series. In this embodiment of the present application, all signals processed by the modules in the communication system 10 are radio frequency signals, which will be simply referred to as signals hereinafter.

[0035] The transmitter 100 is connected to the input side of the power amplifier module 101, and may output a signal of one path, the signal including at least one frequency band signal. The operating frequency band of the transmitter 100 includes at least one frequency band. The transmitter 100 may have the ability to output a signal of at least one frequency band. For example, the transmitter may have the ability to output a signal of a first frequency band, and the signal of one path output by the transmitter 100 may include a signal of the first frequency band. In another example, the transmitter may have the ability to output a signal of the first frequency band or may have the ability to output a signal of a second frequency band. The signal of the path output by the transmitter 100 may include a signal of the first frequency band, or the signal of the path output by the transmitter 100 may include a signal of the second frequency band, or the signal of the path output by the transmitter 100 may include a signal of the first frequency band and a signal of the second frequency band.

[0036] In the communication system 10, the operating frequency band of the power amplifier module 101 may include or cover the operating frequency band of the transmitter 100. The frequency band into which the signal output by the power amplifier module 101 enters is the same as the frequency band into which the signal received by the power amplifier module 101 enters, i.e., the power amplifier module 101 does not change the frequency band of the signal. The power amplifier module 101 may amplify signals of at least one frequency band provided by the transmitter 100. For example, if a signal of one path provided by the transmitter 100 includes a signal of a first frequency band, the power amplifier module 101 may amplify the signal of the first frequency band. In another example, if a signal of one path provided by the transmitter 100 includes a signal of a first frequency band and a signal of a second frequency band, the power amplifier module 101 may amplify the signal of the first frequency band and the signal of the second frequency band.

[0037] The operating frequency band of the radio frequency isolation module 102 may include or cover the operating frequency band supported by the power amplification module 101. Since the operating frequency band of the power amplification module 101 includes or covers the operating frequency band of the transmitter 100, it can be understood that the operating frequency band supported by the radio frequency isolation module 102 also includes or covers the operating frequency band of the transmitter 100. The radio frequency isolation module 102 has signal transmission capability and isolation capability. The radio frequency isolation module 102 provided in this embodiment of the present application can support high-power signal transmission and has lower insertion loss and lower intermodulation distortion. The radio frequency isolation module 102 can isolate signals at the antenna 103 from the power amplification module 101 and prevent signals at the antenna 103 from being transmitted to the power amplification module 101, thereby protecting the power amplification module 101.

[0038] For example, the power amplifier module 101 may include a power splitter 101A, a plurality of power amplifier circuits, and a first combiner 101B. Figure 4 is a diagram of a specific structure of the power amplifier module according to an exemplary embodiment. The power amplifier module 101 may include the power splitter 101A, d power amplifier circuits, and a first combiner 101B, where d is an integer greater than 1.

[0039] The input side of the power splitter 101A may include one first input terminal, and the output side of the power splitter 101A may include d first output terminals. The d first output terminals of the power splitter 101A correspond one-to-one to the d power amplifier circuits. One first output terminal corresponds to one power amplifier circuit, and one power amplifier circuit corresponds to one first output terminal. The power splitter 101A may split a signal of one path received by the first input terminal into d signals and output the d signals to the power amplifier circuits corresponding to the first output terminals by using the d first output terminals. The operating frequency band of the power amplifier module 101 may include one or more frequency bands. The operating frequency band of each power amplifier circuit may be the same as the operating frequency band of the power amplifier module 101. In the d power amplifier circuits of the power amplifier module 101, each power amplifier circuit may amplify a received signal.

[0040] The input side of the first combiner 101B may include d second input terminals, and the output side of the first combiner 101B may include one second output terminal. The d second input terminals may correspond one-to-one to the d power amplifier circuits, with one second input terminal corresponding to one power amplifier circuit and one power amplifier circuit corresponding to one second input terminal. The power amplifier circuit outputs an amplified signal to the corresponding second input terminal. The first combiner 101B may combine the signals received by the second input terminals and output a combined signal by using the second output terminal. For example, the combined signal may be output to the radio frequency isolation module 102. It may be seen that the power amplifier module 101 in the communication system 10 outputs a signal of one path to the radio frequency isolation module 102.

[0041] The power amplification module 101 in the communication system 10 provided in this embodiment of the present application can output higher power. The radio frequency isolation module 102 provided in this embodiment of the present application can support the transmission of signals with higher power. The following describes the radio frequency isolation module 102 provided in this embodiment of the present application.

[0042] 5 shows a radio frequency isolation module according to one embodiment of the present application. The radio frequency isolation module 102 may be coupled to a power amplification module 101. Optionally, the power amplification module 101 may have the structure shown in FIG. 4. Alternatively, the power amplification module 101 may use another structure, which is not particularly limited in this embodiment of the present application.

[0043] The radio frequency isolation module 102 may include a dividing circuit 201, an isolation circuit 202, and a combining circuit 203. The isolation circuit 202 may include at least one isolation branch.

[0044] The dividing circuit 201 may include an input terminal and N output terminals, where the input terminal is coupled to the power amplification module 101 and configured to receive a target radio frequency signal. The target radio frequency signal may include signals of S frequency bands, where S is an integer less than or equal to N. The N output terminals correspond one-to-one to the N frequency bands, one output terminal is coupled to one of the isolation branches, and each output terminal is configured to output a signal of the frequency band corresponding to the coupled isolation branch. The dividing circuit 201 may be configured to divide the target radio frequency signal into signals of each frequency band included in the S frequency bands and output the signals by using the output terminal corresponding to each frequency band.

[0045] Each isolation branch is coupled to a combining circuit 203, and each isolation branch may be configured to transmit a signal provided by one of the output ends of the dividing circuit coupled to the combining circuit 203 and to prevent a signal generated in the combining circuit 203 from being transmitted to the input end coupled to the isolation branch.

[0046] The combining circuit 203 is coupled to the antenna 103 and configured to combine the signals transmitted by the isolation branches in the isolation circuit 202 and output a combined signal to the antenna 103 .

[0047] First, the dividing circuit 201 will be described. The dividing circuit 201 may have frequency dividing capability. When a signal of one path received by the dividing circuit 201 includes signals of multiple frequency bands, the dividing circuit 102 may divide the signal of one path into signals of multiple paths, and each of the signals of the multiple paths obtained through the division includes a signal of a single frequency band. That is, the dividing circuit 201 may divide the signal of one path including signals of multiple frequency bands into signals of multiple paths including signals of a single frequency band for output.

[0048] In one example, a signal of one path received by the splitting circuit 201 includes a signal of a first frequency band and a signal of a second frequency band. The splitting circuit 201 may split the received signal into signals of two paths. The two path signals obtained through the splitting are respectively referred to as a first path signal and a second path signal. The first path signal includes a signal of the first frequency band, and the second path signal includes a signal of the second frequency band. In another example, a signal of one path received by the splitting circuit 201 includes a signal of a first frequency band, a signal of a second frequency band, and a signal of a third frequency band. The splitting circuit 201 may split the received signal into signals of three paths. Of the three signals obtained through the splitting, the first path signal includes a signal of the first frequency band, the second path signal includes a signal of the second frequency band, and the third path signal includes a signal of the third frequency band. In a possible scenario, when the signal of one path received by the splitting circuit 201 includes a signal of one frequency band, the splitting circuit 201 may output the received signal of one path.

[0049] The input side of the divider circuit 201 is coupled to the power amplifier module 101. The input side of the divider circuit 201 has one input end. The input end of the divider circuit 201 may be configured to receive a signal of one path provided by the power amplifier module 101. For example, the input end of the divider circuit 201 may receive the signal provided by the power amplifier module 101. The signal provided by the power amplifier module 101 may include a signal of at least one frequency band.

[0050] The output side of the dividing circuit 201 is coupled to the isolation circuit 202. The output side of the dividing circuit 201 includes a plurality of output terminals. The operating frequency band of the dividing circuit 201 includes N frequency bands, and the output side of the dividing circuit 201 includes N output terminals, where N is an integer greater than 1. The N output terminals correspond one-to-one to the N frequency bands, with one output terminal corresponding to one frequency band and one frequency band corresponding to one output terminal. Each of the N output terminals is configured to output a signal of one path, and the output signal of one path includes a signal of the frequency band corresponding to the output terminal. The plurality of output terminals of the dividing circuit 201 are respectively connected to the isolation circuit 202.

[0051] 6A is a diagram of the structure of a divider circuit according to an exemplary embodiment. The input side of the divider circuit 201 may have one input terminal Z1. The output side of the divider circuit 201 may have N output terminals P, each output terminal outputting a signal of one path. In this case, the N output terminals output signals of N paths. N may be an integer greater than or equal to X. For ease of explanation, the i-th output terminal of the N output terminals is denoted as output terminal Pi, where i can be a value from 1 to N, and the frequency band corresponding to output terminal Pi is denoted as frequency band mi.

[0052] For example, in a scenario where the splitter circuit 201 has three output terminals and the splitter circuit 201 has frequency division processing capability for three frequency bands, that is, when X is 3 and N is 3, the frequency band corresponding to the output terminal P1 is frequency band m1, the frequency band corresponding to the output terminal P2 is frequency band m2, and the frequency band corresponding to the output terminal P3 is frequency band m3.

[0053] The above-described functions of the splitting circuit 201 can be implemented by using one or more splitters. In one example, the splitting circuit 201 can include one splitter. As shown in FIG. 6B, the splitting circuit 201 can include a first splitter. The input side of the first splitter has one input end, and the output side has N output ends. The N output ends of the first splitter can be implemented as the N output ends of the splitting circuit 201.

[0054] In another example, the splitter circuit 201 may include multiple splitters. In the multiple splitters, each splitter may have multiple output ends. As shown in FIG. 6C, the multiple splitters may include a second splitter and at least one third splitter. The input end of the second splitter is the input end of the splitter circuit 201, and the second splitter has multiple output ends. Some output ends may be used as output ends of the splitter circuit 201, and other output ends may be coupled to input ends of at least one third splitter. All output ends of the at least one third splitter may also be used as output ends of the splitter circuit 201.

[0055] As shown in Figure 6D, the multiple splitters may include a second splitter and multiple third splitters. The input end of the second splitter is the input end of the splitting circuit 201, and the second splitter has multiple output ends, and the multiple output ends of the second splitter correspond one-to-one to the multiple third splitters, and one output end of the second splitter is coupled to the input end of the corresponding third splitter. All output ends of the multiple third splitters are used as output ends of the splitting circuit 201.

[0056] In the above example, the specific structure of the splitter circuit 201 shown in Figures 6B to 6D is used only as an example for explanation, which is not limiting in this application.

[0057] The operating frequency band of the radio frequency isolation module 102 provided in the embodiment of the present application includes N frequency bands. In other words, the radio frequency isolation module 102 can support N frequency bands. The operating frequency band of the dividing circuit 201 can cover or include the operating frequency band of the radio frequency isolation module 102.

[0058] In one possible scenario, the operating frequency band of the radio frequency isolation module 102 is the same as the operating frequency band of the split circuit 201. In another possible scenario, the operating frequency band of the split circuit 201 covers the operating frequency band of the radio frequency isolation module 102, and the range of the operating frequency band of the split circuit 201 is greater than the range of the operating frequency band of the radio frequency isolation module 102. For example, the operating frequency band of the radio frequency isolation module 102 may include N frequency bands, and the output side of the split circuit 102 may include X output terminals, and the X output terminals may include the above-mentioned N output terminals. In this case, X is greater than N. That is, the X frequency bands supported by the split circuit 102 include the N frequency bands supported by the radio frequency isolation module 102. In this case, the N output terminals of the X output terminals of the split circuit 201 may correspond one-to-one to the N frequency bands supported by the radio frequency isolation module 102.

[0059] Still referring to FIG. 5 , the isolation circuit 202 is coupled to the input side of the combining circuit 203, and may have the ability to transmit signals unidirectionally. The isolation circuit 202 transmits signals of at least one path provided by the dividing circuit 201 to the combining circuit 203, and may separate signals generated in the combining circuit 203 from the dividing circuit 201. Since the signal of one path output by the dividing circuit 201 includes only signals of a single frequency band, and different output ends output signals of different frequency bands, the isolation circuit 202 transmits signals of at least one path provided by the dividing circuit 201 to the combining circuit 203, and the isolation circuit 202 transmits signals of at least one frequency band to the combining circuit 203.

[0060] The output side of the combining circuit 203 is coupled to the antenna 103, and the combining circuit 203 may have filtering and inter-frequency combining functions. The combining circuit 203 combines multiple path signals of different frequency bands on the input side of the dividing circuit 201 into one path signal and outputs the path signal to the antenna 103. Alternatively, the combining circuit 203 may be configured to perform inter-frequency combining on the multiple path signals transmitted by the isolation circuit 202 and output the one path signal to the antenna 103. The path signal output by the combining circuit 203 to the antenna 103 includes signals of at least two frequency bands.

[0061] 6A, among the N output terminals of the dividing circuit 201, it is assumed that the output terminal P1 corresponds to a first frequency band and the output terminal P2 corresponds to a second frequency band. In one example, a signal of one path provided by the power amplifier module 101 to the dividing circuit 201 includes a signal of the first frequency band and a signal of the second frequency band. After frequency division processing is performed on the signal that can be received by the dividing circuit 201, the signal of the first frequency band is output by using the output terminal P1, and the signal of the second frequency band is output by using the output terminal P2. The isolation circuit 202 may transmit the signal of the first frequency band provided by the output terminal P1 and the signal of the second frequency band provided by the output terminal P2 to the combining circuit 203. The combining circuit 203 may combine the signal in the first frequency band provided by the output terminal P1 and the signal in the second frequency band provided by the output terminal P2, i.e., combine the signals of the two paths into a signal of one path, and provide the combined signal to the antenna 103. In this case, the signal of one path output by the combining circuit 203 to the antenna includes the signal in the first frequency band and the signal in the second frequency band.

[0062] The operating frequency band of the isolation circuit 202 can be the same as the operating frequency band of the radio frequency isolation module 102, or the operating frequency band of the isolation circuit 202 can cover the operating frequency band of the radio frequency isolation module 102. In a possible design, the output side of the dividing circuit 201 has N output ends, and the isolation circuit 202 includes N isolation branches. In other words, the number of isolation branches in the isolation circuit 202 is the same as the number of output ends of the dividing circuit 201. The number of isolation branches in the isolation circuit 202 is the same as the number of input ends of the combining circuit 203. The following provides separate explanations using examples.

[0063] In a possible design, Figure 7A is an example diagram of a specific structure of a radio frequency isolation module. The radio frequency isolation module 102 may be coupled to a power amplification module 101. Optionally, the power amplification module 101 may have the structure shown in Figure 4. Alternatively, the power amplification module 101 may use another structure, which is not particularly limited in this embodiment of the present application.

[0064] In the radio frequency isolation module 102, the dividing circuit 201 may have N output ends, and the isolation circuit 202 may include N isolation branches. The N isolation branches may correspond one-to-one to the N output ends P of the dividing circuit 201. One isolation branch corresponds to one output end, and one output end corresponds to one isolation branch, and the isolation branch is coupled to the output end P corresponding to the isolation branch. For ease of explanation, the isolation branch corresponding to the output end Pi is denoted as the isolation branch Qi, where i can be a value from 1 to N. The operating frequency band of the isolation branch Qi may include the frequency band corresponding to the output end Pi. For example, the frequency band corresponding to the output end P1 is frequency band m1, and the operating frequency band of the isolation branch Q1 includes or covers frequency band m1. In some examples, the operating frequency band of the isolation branch Qi is the same as the frequency band corresponding to the output end Pi. In some other examples, the operating frequency band of the isolation branch Qi may include the frequency band corresponding to the output end Pi, or the operating frequency band of the isolation branch Qi covers the frequency band corresponding to the output end Pi.

[0065] The input side of the combining circuit 203 may have N input terminals, which correspond one-to-one to the N isolation branches. One isolation branch corresponds to one input terminal, and one input terminal corresponds to one isolation branch, and the isolation branch is coupled to the corresponding input terminal. For ease of explanation, the i-th input terminal of the N input terminals of the combining circuit 203 is denoted as input terminal Ki.

[0066] The signal output by the output end Pi of the dividing circuit 201 can be transmitted to the input end Ki of the combining circuit 203 through the isolation branch Qi. The output ends of the dividing circuit 201 are each transmitted to the combining circuit 203 using one path of the isolation branch. It can be seen that any isolation branch Qi can separate a reflected signal generated in the combining circuit 203 and prevent the reflected signal from affecting the power amplifier module 101. Any isolation branch Qi can include an isolator or a circulator. Such a design can reduce the requirement for the isolation branch Qi relative to the operating frequency band range, and an isolator or circulator with a smaller operating frequency band range can be used to reduce the insertion loss and intermodulation distortion range of the radio frequency isolation module 102. The intermodulation distortion generated by an isolator or circulator with a smaller operating frequency band range when the transmission signal power is at its maximum power can meet the communication system's requirements for intermodulation distortion. An isolator or circulator with a small operating frequency band range can operate at full power, and therefore the radio frequency isolation module 102 can support higher power.

[0067] In some scenarios, the combining circuit 203 may include a multi-band combiner, a first side of which may be coupled to an input end of the combining circuit 203, and a second side of which may be coupled to the antenna 103.

[0068] In some other scenarios, the combining circuit 203 may include a multi-band combiner and at least one filter. The at least one filter may correspond one-to-one with at least one input terminal of the combining circuit 203. In other words, the at least one filter in the combining circuit 203 may correspond one-to-one with at least one isolation branch in the isolation circuit 202. The input terminal of each filter may be coupled to the corresponding input terminal, or the input terminal of each filter may be used as an input terminal of the combining circuit 203 and coupled to the corresponding isolation branch. The output terminal of each filter is coupled to the multi-band combiner. Each filter may have a filtering function, for example, to filter out noise signals. The operating frequency band of each filter may be the same as the operating frequency band of the isolation branch to which it is coupled. Each filter may perform filtering on the signal provided by the isolation branch to which it is coupled and then output the signal to the multi-band combiner. In some cases, multiple filters provide signals to the multi-band combiner. The multi-band combiner may perform inter-frequency synthesis processing on the signals provided by the multiple filters and then output a signal of one path, which is sent to the antenna 103 for transmission. In another possible case, one filter may provide a signal to the multi-band combiner, which may also output the signal provided by the filter to the antenna 103 for transmission.

[0069] 7A , as shown in FIG. 7B , the radio frequency isolation module 102 may further include N functional circuits, where the N isolation branches in the isolation circuit 202 correspond one-to-one to the N functional circuits. The functional circuit corresponding to the isolation branch Qi may be indicated as a functional circuit Wi, where i may be a value from 1 to N. The isolation branch Qi is coupled to the input end Ki of the combining circuit 203 by using the functional circuit Wi. In one example, the functional circuit Qi may be configured to perform impedance matching for the signal transmitted by the isolation branch Qi.

[0070] In one example, Figure 8 is a diagram of a specific structure of the radio frequency isolation module 102. The radio frequency isolation module 102 may be coupled to the power amplification module 101. Optionally, the power amplification module 101 may have the structure shown in Figure 4. Alternatively, the power amplification module 101 may use another structure, which is not particularly limited in this embodiment of the present application.

[0071] The operating frequency band of the radio frequency isolation module 102 may include two frequency bands, designated as a first frequency band and a second frequency band, respectively. The dividing circuit 201 may include two output terminals. The output terminal P1 corresponds to the first frequency band, and the output terminal P2 corresponds to the second frequency band. The isolation circuit 202 may include two isolation branches, designated as an isolation branch Q1 and an isolation branch Q2, respectively. The isolation branch Q1 is coupled to the output terminal P1, and the isolation branch Q2 is coupled to the output terminal P2. The combining circuit 203 has two input terminals, designated as an input terminal K1 and an input terminal K2, respectively. The input terminal K1 is coupled to the isolation branch Q1, and the input terminal K2 is coupled to the isolation branch Q2.

[0072] The dividing circuit 201 may perform inter-frequency division processing on the received signal. If the signal received by the dividing circuit 201 includes a signal of a first frequency band, the dividing circuit 201 may output the signal of the first frequency band by using the output terminal P1. If the signal received by the dividing circuit 201 includes a signal of a second frequency band, the dividing circuit 201 may output the signal of the second frequency band by using the output terminal P2. If the signal received by the dividing circuit 201 includes a signal of the first frequency band and a signal of the second frequency band, after performing inter-frequency division processing on the received signal, the dividing circuit 201 outputs the signal of the first frequency band by using the output terminal P1 and outputs the signal of the second frequency band by using the output terminal P2.

[0073] The isolation branch Q1 may transmit a signal of a first frequency band provided by the output terminal P1 to the input terminal K1 of the combining module and may prevent a reflected signal generated in the combining circuit 203 from being transmitted to the output terminal P1. The isolation branch Q2 may transmit a signal of a second frequency band provided by the output terminal P2 to the input terminal K2 of the combining circuit 203 and may prevent a reflected signal generated in the combining circuit 203 from being transmitted to the output terminal P2. The combining circuit 203 may perform inter-frequency synthesis on the signal of the first frequency band and the signal of the second frequency band provided by the isolation branch Q1 and the isolation branch Q2, respectively, to combine the signals into a signal of one path and output the combined signal to the antenna 103.

[0074] In the above embodiment, the first frequency band may be the 758 MHz to 960 MHz frequency band and the second frequency band may be the 1.8 GHz frequency band. Alternatively, the first frequency band may be the 758 MHz to 960 MHz frequency band and the second frequency band may be the 2.1 GHz frequency band. Alternatively, the first frequency band may be the 758 MHz to 960 MHz frequency band and the second frequency band may be the 2.6 GHz frequency band. Alternatively, the first frequency band may be the 1.8 GHz frequency band and the second frequency band may be the 2.1 GHz frequency band. Alternatively, the first frequency band may be the 1.8 GHz frequency band and the second frequency band may be the 2.6 GHz frequency band. Alternatively, the first frequency band may be the 2.6 GHz frequency band and the second frequency band may be the 2.1 GHz frequency band.

[0075] In another example, Figure 9 is a diagram of a specific structure of a radio frequency isolation module. The radio frequency isolation module 102 may be coupled to a power amplification module 101. Optionally, the power amplification module 101 may have the structure shown in Figure 4. Alternatively, the power amplification module 101 may use another structure, which is not particularly limited in this embodiment of the present application.

[0076] The radio frequency isolation module 102 may support three frequency bands, which are respectively referred to as a first frequency band, a second frequency band, and a third frequency band. The splitter circuit 201 may include three output terminals. The output terminal P1 corresponds to the first frequency band, the output terminal P2 corresponds to the second frequency band, and the output terminal P3 corresponds to the third frequency band.

[0077] The isolation circuit 202 may include three isolation branches: isolation branch Q1 coupled to output terminal P1, isolation branch Q2 coupled to output terminal P2, and isolation branch Q3 coupled to output terminal P3. The combining circuit 203 has three input terminals: input terminal K1 coupled to isolation branch Q1, input terminal K2 coupled to isolation branch Q2, and output terminal K3 coupled to isolation branch Q3.

[0078] The dividing circuit 201 may perform inter-frequency division processing on the received signal. If the signal received by the dividing circuit 201 includes a signal in a first frequency band, the dividing circuit 201 may output the signal in the first frequency band by using the output terminal P1. If the signal received by the dividing circuit 201 includes a signal in a second frequency band, the dividing circuit 201 may output the signal in the second frequency band by using the output terminal P2. If the signal received by the dividing circuit 201 includes a signal in a third frequency band, the dividing circuit 201 may output the signal in the third frequency band by using the output terminal P3. If the signal received by the dividing circuit 201 includes a signal in the first frequency band and a signal in the second frequency band, after performing inter-frequency division processing on the received signal, the dividing circuit 201 outputs the signal in the first frequency band by using the output terminal P1 and outputs the signal in the second frequency band by using the output terminal P2. When the signal received by the division circuit 201 includes a signal of a first frequency band and a signal of a third frequency band, after performing inter-frequency division processing on the received signal, the division circuit 201 outputs the signal of the first frequency band by using the output terminal P1 and outputs the signal of the third frequency band by using the output terminal P3. When the signal received by the division circuit 201 includes a signal of a second frequency band and a signal of a third frequency band, after performing inter-frequency division processing on the received signal, the division circuit 201 outputs the signal of the second frequency band by using the output terminal P2 and outputs the signal of the third frequency band by using the output terminal P3. When the signal received by the division circuit 201 includes a signal of a first frequency band, a signal of a second frequency band, and a signal of a third frequency band, after performing inter-frequency division processing on the received signal, the division circuit 201 outputs the signal of the first frequency band by using the output terminal P1, outputs the signal of the second frequency band by using the output terminal P2, and outputs the signal of the third frequency band by using the output terminal P3.

[0079] The isolation branch Q1 may transmit a signal of a first frequency band to the input terminal K1 of the combining circuit 203 and may prevent a reflected signal generated in the combining circuit 203 from being transmitted to the output terminal P1. The isolation branch Q2 may transmit a signal of a second frequency band to the input terminal K2 of the combining circuit 203 and may prevent a reflected signal generated in the combining circuit 203 from being transmitted to the output terminal P2. The isolation branch Q3 may transmit a signal of a third frequency band to the input terminal K3 of the combining circuit 203 and may prevent a reflected signal generated in the combining circuit 203 from being transmitted to the output terminal P3. The combining circuit 203 may perform inter-frequency synthesis on the signals of the first frequency band, the second frequency band, and the third frequency band provided by the isolation branch Q1, the isolation branch Q2, and the isolation branch Q3, respectively, and may combine the signals into a signal of one path and then output the combined signal to the antenna.

[0080] In the above embodiment, the first frequency band may be the 758 MHz to 960 MHz frequency band, the second frequency band may be the 1.8 GHz frequency band, and the third frequency band may be the 2.1 GHz frequency band. Alternatively, the first frequency band may be the 758 MHz to 960 MHz frequency band, the second frequency band may be the 2.1 GHz frequency band, and the third frequency band may be the 2.6 GHz frequency band. Alternatively, the first frequency band may be the 758 MHz to 960 MHz frequency band, the second frequency band may be the 2.6 GHz frequency band, and the third frequency band may be the 1.8 GHz frequency band. Alternatively, the first frequency band may be the 1.8 GHz frequency band, the second frequency band may be the 2.1 GHz frequency band, and the third frequency band may be the 2.6 GHz frequency band.

[0081] In another possible implementation, the quantity of the output ends of the dividing circuit 201 can be greater than the quantity of the isolation branches in the isolation circuit 202, and the quantity of the isolation branches in the isolation circuit 202 is the same as the quantity of the input ends of the combining circuit 203. The following provides an explanation separately by using an example. In this implementation, the isolation circuit 202 can include M isolation branches, where M is an integer smaller than N.

[0082] In a possible design, FIG. 10 is an example diagram of a specific structure of a radio frequency isolation module. The radio frequency isolation module 102 may be coupled to a power amplification module 101. Optionally, the power amplification module 101 may have the structure shown in FIG. 4. Alternatively, the power amplification module 101 may use another structure, which is not particularly limited in this embodiment of the present application. For the division circuit 201 in the radio frequency isolation module, please refer to the related description of the division circuit 201 shown in FIG. 4. The details will not be described again here.

[0083] In the isolation circuit 202 of the radio frequency isolation module 102, the M isolation branches are M first isolation branches, which are respectively indicated as first isolation branch Mr-1, first isolation branch Mr-2, ..., first isolation branch Mr-M. For the dividing circuit 201 in the radio frequency isolation module, please refer to the related description of the dividing circuit 201 shown in Figure 6A. Details will not be described again here.

[0084] One output end of the dividing circuit 201 is coupled to only one of the M first isolation branches. In the M first isolation branches, the input side of any first isolation branch Mr may be coupled to multiple output ends of the dividing circuit 201, or any first isolation branch Mr may be coupled to at least two output ends of the dividing circuit 201, and the first isolation branch Mr may receive signals provided by the at least two output ends. The output side of any first isolation branch Mr is coupled to the input end of the combining circuit 203.

[0085] For example, the first isolation branch Mr-1 is coupled to the output terminal P1 and the output terminal P2 of the splitter circuit 201 and to the input terminal K1 of the combiner circuit 203. The operating frequency band of the first isolation branch Mr-1 may include the frequency band corresponding to the output terminal P1 and the frequency band corresponding to the output terminal P2. The first isolation branch Mr-1 may transmit signals provided by the output terminal P1 and the output terminal P2 to the input terminal K1 of the combiner circuit 203 and may prevent reflected signals generated in the combiner circuit 203 from being transmitted to the output terminal P1 and the output terminal P2 of the splitter circuit 201.

[0086] Similarly, the first isolation branch Mr-2 is coupled to the output terminal P3 and the output terminal P4 of the splitter circuit 201 and to the input terminal K2 of the combiner circuit 203. The operating frequency band of the first isolation branch Mr-2 may include the frequency band corresponding to the output terminal P3 and the frequency band corresponding to the output terminal P4. The first isolation branch Mr-2 may transmit signals provided by the output terminal P3 and the output terminal P4 to the input terminal K2 of the combiner circuit 203 and may prevent reflected signals generated in the combiner circuit 203 or the antenna 103 from being transmitted to the output terminal P3 and the output terminal P4 of the splitter circuit 201.

[0087] Note that in some scenarios, the amount of output ends of the divider circuit 201 coupled to the first isolation branches may be the same. For example, in the above example, both the first isolation branch Mr-1 and the first isolation branch Mr-2 are connected to two input ends. In other words, the amount of frequency bands covered by the operating frequency bands of the first isolation branches may be the same. The first isolation branch Mr-1 covers two frequency bands, which are the frequency bands corresponding to the output ends P1 and P2, respectively. The first isolation branch Mr-2 covers two frequency bands, which are the frequency bands corresponding to the output ends P3 and P4, respectively.

[0088] In some other scenarios, the amount of output ends connected to the first isolation branch may be different, or the amount of the frequency band covered by the operating frequency band of the first isolation branch may be different, which is not limited in the embodiments of the present application.

[0089] In another possible design, the M isolation branches include at least one first isolation branch Mr and at least one second isolation branch Ms. One output end of the splitting circuit 201 is coupled to only one isolation branch among the M isolation branches, or one output end of the splitting circuit 201 is coupled to one first isolation branch or one second isolation branch.

[0090] In this design, the input side of any first isolation branch Mr among the M isolation branches may be coupled to multiple output ends of the splitter circuit 201, or the first isolation branch Mr may be coupled to at least two output ends of the splitter circuit 201, and the first isolation branch Mr may receive signals provided by the at least two output ends. The output side of any first isolation branch Mr is coupled to one input end of the combiner circuit 203. Optionally, the output end of any first isolation branch Mr may be coupled to one input end of the combiner circuit 203 by using a functional circuit, and the functional circuit coupled to the output end of the first isolation branch Mr may be configured to perform impedance matching for the signal provided by the output end of the first isolation branch Mr.

[0091] An input side of any second isolation branch Ms among the M isolation branches may be coupled to one output end of the splitting circuit 201, and the second isolation branch Ms may receive a signal provided by the output end. An output side of the second isolation branch Ms is coupled to one input end of the combining circuit 203. Optionally, the output end of any second isolation branch Ms may be coupled to one input end of the combining circuit 203 by using a functional circuit, and the functional circuit coupled to the output end of the second isolation branch Ms may be configured to perform impedance matching for the signal provided by the output end of the second isolation branch Ms.

[0092] In such a design, among the M isolation branches, a first isolation branch may include an isolator or a circulator, and a second isolation branch may include an isolator or a circulator, and the amount of the frequency band covered by the operating frequency band of the first isolation branch may be equal to or greater than the amount of the frequency band covered by the operating frequency band of the second isolation branch.

[0093] 11 is an example of a diagram of a specific structure of a radio frequency isolation module. A radio frequency isolation module 102 may be coupled to a power amplification module 101. Optionally, the power amplification module 101 may have the structure shown in FIG. 4. Alternatively, the power amplification module 101 may use another structure, which is not particularly limited in this embodiment of the present application. For the division circuit 201 in the radio frequency isolation module, please refer to the related description of the division circuit 201 shown in FIG. 4. Details will not be described again here.

[0094] The isolation circuit 202 includes M isolation branches. The M isolation branches may include z first isolation branches Mr and x second isolation branches Ms, where z is an integer greater than or equal to 1, x is an integer greater than or equal to 1, and the sum of z and x is M. Note that although the isolation circuit 202 in FIG. 11 shows a case where z is 2, this is not used as a specific limitation on the value of z.

[0095] For example, still refer to FIG. 11. The M isolation branches include two first isolation branches and x second isolation branches, where the value of x is M-2. The two first isolation branches are denoted as first isolation branch Mr-1 and first isolation branch Mr-2, respectively. The x second isolation branches are denoted as second isolation branch Ms-1, ..., and second isolation branch Ms-x, respectively.

[0096] The first isolation branch Mr-1 is coupled to the output terminals P1 and P2 of the splitter circuit 201 and to the input terminal K1 of the combiner circuit 203. The operating frequency band of the first isolation branch Mr-1 may include the frequency band corresponding to the output terminal P1 and the frequency band corresponding to the output terminal P2. The first isolation branch Mr-1 may transmit signals provided by the output terminals P1 and P2 to the input terminal K1 of the combiner circuit 203 and may prevent reflected signals generated in the combiner circuit 203 from being transmitted to the output terminals P1 and P2 of the splitter circuit 201.

[0097] Similarly, the first isolation branch Mr-2 is coupled to the output terminal P3 and the output terminal P4 of the splitter circuit 201 and to the input terminal K2 of the combiner circuit 203. The operating frequency band of the first isolation branch Mr-2 may include the frequency band corresponding to the output terminal P3 and the frequency band corresponding to the output terminal P4. The first isolation branch Mr-2 may transmit signals provided by the output terminal P3 and the output terminal P4 to the input terminal K2 of the combiner circuit 203 and may prevent reflected signals generated in the combiner circuit 203 or the antenna 103 from being transmitted to the output terminal P3 and the output terminal P4 of the splitter circuit 201.

[0098] The second isolation branch Ms-1 is coupled to the output terminal P5 of the splitter circuit 201 and to the output terminal K3 of the combiner circuit 203. The operating frequency band of the second isolation branch Ms-1 may include the frequency band corresponding to the output terminal P5. The second isolation branch Ms-1 may transmit a signal provided by the output terminal P5 to the input terminal K3 of the combiner circuit 203 and prevent a reflected signal generated in the combiner circuit 203 from being transmitted to the output terminal P5 of the splitter circuit 201.

[0099] Similarly, the second isolation branch Ms-x is coupled to the output end PN of the splitter circuit 201 and to the output end KM of the combiner circuit 203. The operating frequency band of the second isolation branch Ms-x may include the frequency band corresponding to the output end PN. The second isolation branch Ms-x may transmit the signal provided by the output end PN to the input end KM of the combiner circuit 203 and prevent the reflected signal generated in the combiner circuit 203 from being transmitted to the output end PN of the splitter circuit 201.

[0100] It can be seen from the above description that the signal output by the output terminal Pi of the dividing circuit 201 can be transmitted to the combining circuit 203 by using an isolation branch coupled to the output terminal Pi. Furthermore, the isolation branch coupled to the output terminal Pi can separate the reflected signal generated in the combining circuit 203 and prevent the reflected signal from affecting the power amplifier module. Each isolation branch can include an isolator or a circulator. Such a design can reduce the requirement of each isolation branch for the range of the operating frequency band, and an isolator or circulator with a small operating frequency band range can be used to reduce the insertion loss and intermodulation distortion range of the radio frequency isolation module. Furthermore, the radio frequency isolation module can support higher power.

[0101] In another example, Figure 12 is a diagram of a specific structure of a radio frequency isolation module. The radio frequency isolation module 102 can be coupled to the power amplification module 101. Optionally, the power amplification module 101 can have the structure shown in Figure 4. Alternatively, the power amplification module 101 can use another structure, which is not particularly limited in this embodiment of the present application. For the division circuit 201 in the radio frequency isolation module, please refer to the related description of the division circuit 201 shown in Figure 4. Details will not be described again here.

[0102] The radio frequency isolation module 102 may support three frequency bands, which are designated as a first frequency band, a second frequency band, and a third frequency band, respectively. The dividing circuit 201 may include three output terminals. The output terminal P1 corresponds to the first frequency band, the output terminal P2 corresponds to the second frequency band, and the output terminal P3 corresponds to the third frequency band. The isolation circuit 202 includes two isolation branches, which are designated as a first isolation branch Mr-1 and a second isolation branch Ms-1, respectively.

[0103] The first isolation branch Mr-1 is coupled to output terminals P1 and P2, and the second isolation branch Ms-1 is coupled to output terminal P3. The combining circuit 203 has two input terminals, input terminal K1 is coupled to the first isolation branch Mr-1, and input terminal K2 is coupled to the second isolation branch Ms-1.

[0104] The dividing circuit 201 may perform inter-frequency division processing on the received signal. If the signal received by the dividing circuit 201 includes a signal in a first frequency band, the dividing circuit 201 may output the signal in the first frequency band by using the output terminal P1. If the signal received by the dividing circuit 201 includes a signal in a second frequency band, the dividing circuit 201 may output the signal in the second frequency band by using the output terminal P2. If the signal received by the dividing circuit 201 includes a signal in a third frequency band, the dividing circuit 201 may output the signal in the third frequency band by using the output terminal P3. If the signal received by the dividing circuit 201 includes a signal in the first frequency band and a signal in the second frequency band, after performing inter-frequency division processing on the received signal, the dividing circuit 201 outputs the signal in the first frequency band by using the output terminal P1 and outputs the signal in the second frequency band by using the output terminal P2. When the signal received by the dividing circuit 201 includes a signal of a first frequency band and a signal of a third frequency band, after performing inter-frequency division processing on the received signal, the dividing circuit 201 may output the signal of the first frequency band by using the output terminal P1 and output the signal of the third frequency band by using the output terminal P3. When the signal received by the dividing circuit 201 includes a signal of a second frequency band and a signal of a third frequency band, after performing inter-frequency division processing on the received signal, the dividing circuit 201 may output the signal of the second frequency band by using the output terminal P2 and output the signal of the third frequency band by using the output terminal P3. When the signal received by the division circuit 201 includes a signal of a first frequency band, a signal of a second frequency band, and a signal of a third frequency band, after performing inter-frequency division processing on the received signal, the division circuit 201 outputs the signal of the first frequency band by using the output terminal P1, outputs the signal of the second frequency band by using the output terminal P2, and outputs the signal of the third frequency band by using the output terminal P3.

[0105] The first isolation branch Mr-1 may transmit a signal in a first frequency band provided by the output terminal P1 to the input terminal K1 of the combining circuit 203, and may transmit a signal in a second frequency band provided by the output terminal P2 to the input terminal K1 of the combining circuit 203, and may prevent a reflected signal generated in the combining circuit 203 from being transmitted to the output terminals P1 and P2. The second isolation branch Ms-1 may transmit a signal in a third frequency band provided by the output terminal P3 to the input terminal K3 of the combining circuit 203, and may prevent a reflected signal generated in the combining circuit 203 from being transmitted to the output terminal P3. The combining circuit 203 may perform inter-frequency combining on the signal in the first frequency band and the signal in the second frequency band provided by the first isolation branch Mr-1 and the signal in the third frequency band provided by the second isolation branch Ms-1, combine the signals into a signal of one path, and then output the combined signal to the antenna 103.

[0106] In the above embodiment, the first frequency band may be the 758 MHz to 960 MHz frequency band, the second frequency band may be the 1.8 GHz frequency band, and the third frequency band may be the 2.1 GHz frequency band. Alternatively, the first frequency band may be the 758 MHz to 960 MHz frequency band, the second frequency band may be the 2.1 GHz frequency band, and the third frequency band may be the 2.6 GHz frequency band. Alternatively, the first frequency band may be the 758 MHz to 960 MHz frequency band, the second frequency band may be the 2.6 GHz frequency band, and the third frequency band may be the 1.8 GHz frequency band. Alternatively, the first frequency band may be the 1.8 GHz frequency band, the second frequency band may be the 2.1 GHz frequency band, and the third frequency band may be the 2.6 GHz frequency band.

[0107] It is obvious that those skilled in the art can make various modifications and changes to the present application without departing from the scope of protection of the present application. In this case, if the modifications and changes of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also includes the modifications and changes.

Claims

1. a radio frequency isolation module configured to transmit a target radio frequency signal provided by a power amplification module to an antenna, an operating frequency band of the radio frequency isolation module covering an operating frequency band of the power amplification module, the operating frequency band of the radio frequency isolation module comprising N frequency bands, N being an integer greater than 1; the radio frequency isolation module comprising a dividing circuit, an isolation circuit, and a combining circuit, the isolation circuit comprising at least one isolation branch; the dividing circuit has an input terminal and N output terminals, the input terminal is coupled to the power amplification module and configured to receive the target radio frequency signal, the target radio frequency signal comprising signals of S frequency bands, S being an integer equal to or less than N, the N output terminals corresponding one-to-one to the N frequency bands, one output terminal being coupled to one isolation branch, each output terminal being configured to output a signal of a frequency band corresponding to the coupled isolation branch, the dividing circuit being configured to divide the target radio frequency signal into signals of each frequency band comprised in the S frequency bands, and output the signals by using the output terminal corresponding to each frequency band; each isolation branch is coupled to the combining circuit and configured to transmit a signal provided by an output end of one of the dividing circuits coupled to the combining circuit and to prevent a signal generated in the combining circuit from being transmitted to an input end coupled to the isolation branch; The combining circuit is coupled to the antenna and configured to combine signals transmitted by isolation branches in the isolation circuit and output a combined signal to the antenna.

2. the isolation circuit includes N isolation branches, the N isolation branches corresponding one-to-one to the N output terminals; 2. The module of claim 1, wherein the operating frequency band of the isolation branch covers a frequency band corresponding to the output end coupled to the isolation branch.

3. the isolation circuit comprises M isolation branches, where M is an integer less than N, one of the M isolation branches being coupled to at least one of the output ends; 2. The module of claim 1, wherein the operating frequency band of the isolation branch covers a frequency band corresponding to each of the at least one output end coupled to the isolation branch.

4. 4. The module of claim 1, wherein the splitting circuit comprises at least one splitter.

5. 5. The module of claim 1, wherein the isolation branch comprises an isolator.

6. 5. The module of claim 1, wherein the isolation branch comprises a circulator.

7. 7. The module of claim 1, wherein the combining circuit comprises a multi-band combiner.

8. 8. The module of claim 7, wherein the combining circuit comprises at least one filter, the at least one isolation branch having a one-to-one correspondence with the at least one filter, each isolation branch being coupled to the multi-band combiner by using a corresponding filter, and an operating frequency band of each filter being the same as an operating frequency band of the coupled isolation branch.

9. A communication system comprising a transmitter, a power amplifier module, and the radio frequency isolation module according to any one of claims 1 to 7, the transmitter is configured to generate a first radio frequency signal; the power amplification module is separately coupled to the transmitter and the radio frequency isolation module, and is configured to amplify the first radio frequency signal to obtain a second radio frequency signal, and output the second radio frequency signal to the radio frequency isolation module; The communication system, wherein the radio frequency isolation module is configured to be coupled to an antenna, and the radio frequency isolation module is configured to transmit the second radio frequency signal to the antenna.

10. the power amplifier module includes a power splitter, a plurality of power amplifier circuits, and a first combiner; the power splitter is coupled to each power amplifier circuit and configured to perform power allocation on the first radio frequency signals and output third radio frequency signals to each power amplifier circuit, wherein a sum of powers of all third radio frequency signals output by the power splitter is equal to a power of the first radio frequency signal; each power amplifier circuit is coupled to the first combiner and configured to perform power amplification on the received third radio frequency signal and output the third radio frequency signal to the combiner; 10. The system of claim 9, wherein the combiner is coupled to the radio frequency isolation module and configured to combine the signals separately output by the plurality of power amplification circuits to obtain the second radio frequency signal and output the second radio frequency signal to the radio frequency isolation module.

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