Radio frequency power amplifiers, remote radio units, and base stations

Abstract

This application discloses a radio frequency power amplifier, a remote radio unit, and a base station. The radio frequency power amplifier includes three amplifier branches. In this specification, two amplifier branches have narrow operating frequency bands and operate on frequency band A and frequency band B, respectively, and the other amplifier branch is designed to have a wide frequency band and operates on frequency band A+B. The radio frequency power amplifier further includes an inter-frequency power divider circuit and two circulators. The inter-frequency power divider circuit performs inter-frequency power division on the output signal of the wideband amplifier branch to output two narrowband signals, which are output after being power-combined by the circulator. Based on the technical solution of this application, a wideband problem is converted into a narrowband problem, thereby improving power amplification efficiency. In addition, the wideband amplifier branch provides a power distribution function, thereby processing high-power wideband signals. A narrowband isolator is used at a lower level of the circulator, thereby reducing the difficulty of designing the isolator.

Description

[Technical Field]

[0001] This application relates to the field of communications equipment, and more particularly to radio frequency power amplifiers, remote radio units, and base stations. [Background technology]

[0002] Due to the scarce spectrum resources in wireless communications, complex modulation schemes are widely applied in communication systems to improve spectrum utilization. In this case, the peak-to-average ratio of the modulated signal becomes very high. For example, in a 5G communication system, even after peak clipping, the signal's peak-to-average ratio remains as high as 9.5 dB. In such a large power backoff range, conventional power amplifiers (PAs) typically face the problem of low backoff efficiency. Furthermore, in most service scenarios on live networks, the number of user services is low, so PAs typically operate in a larger backoff state. This results in low PA efficiency and high power consumption. This brings new challenges to power amplifiers in base stations. Current and future wireless communication systems urgently require PAs to have higher efficiency under higher power backoff. Furthermore, to meet the requirements of high speed and low latency in current and future communications, signal bandwidths are becoming increasingly wider and the spectrum of wireless communication systems is becoming more fragmented, requiring PAs to support wideband multi-frequency capabilities. Therefore, with the development of wireless communication systems, power amplifiers in base stations need to support ultra-wideband functionality and achieve high efficiency.

[0003] Currently, it is very difficult for base station PAs, especially high-power PAs, to achieve ultra-wideband and high efficiency. In addition to the trade-off between PA bandwidth and backoff, another reason is that increasing the PA's output power leads to an increase in the size of the internal power tube. In this case, the operating bandwidth of the power tube decreases due to factors such as parasitic parameters and impedance transformation ratio.

[0004] Furthermore, isolators, especially those cascaded at the final output of a PA, are a key component of a PA. The function of the final isolator is to ensure that the performance of the PA is not affected by mismatches with antennas and the like. However, in the design of ultra-wideband PAs, for example, the relative bandwidth of 1.8 to 2.7 GHz accounts for about 40% of the total bandwidth, and ultra-wideband isolators usually face problems such as large insertion loss and poor linearity index. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the present invention provides a radio frequency power amplifier, a remote radio unit, and a base station, which are configured to implement ultra-wideband functions and achieve high efficiency, and are particularly suitable for high-power, ultra-wideband, and energy-saving scenarios.

[0006] The radio frequency power amplifier provided in the present application is not particularly limited in the number of input signal paths, and the number may be, for example, N, where N is an integer greater than or equal to 3. The radio frequency power amplifier may include N amplifier branches, N-1 circulators, and at least one inter-frequency power divider circuit. For example, the radio frequency power amplifier may include three amplifier branches, two circulators, and one inter-frequency power divider circuit. The three amplifier branches are configured to input three-path signals, respectively. The output end of the third amplifier branch is connected to the input end of the first inter-frequency power divider circuit. The operating frequency band of the first amplifier branch and the first circulator is frequency band A, the operating frequency band of the second amplifier branch and the second circulator is frequency band B, and the operating frequency bands of the third amplifier branch are frequency band A and frequency band B. The first inter-frequency power divider circuit outputs frequency band A signals and frequency band B signals. The output end of the first amplifier branch and the first output end of the first frequency power divider circuit are respectively connected to different ports of a first circulator, and the first circulator performs power combining on the frequency band A signal output from the first amplifier branch and the frequency band A signal output from the first frequency power divider circuit, and then outputs the combined signal. The output end of the second amplifier branch and the second output end of the first frequency power divider circuit are respectively connected to different ports of a second circulator, and the second circulator performs power combining on the frequency band B signal output from the second amplifier branch and the frequency band B signal output from the first frequency power divider circuit, and then outputs the combined signal.

[0007] The frequency band A and frequency band B described in the above-mentioned embodiments of the present application may be a single frequency band or multiple frequency bands. Also, frequency band A and frequency band B are different frequency bands. In other words, frequency band A and frequency band B do not have overlapping frequency band ranges, i.e., these two frequency bands do not have overlapping frequencies. The frequency of frequency band A may be higher than the frequency of frequency band B, or the frequency of frequency band A may be lower than the frequency of frequency band B.

[0008] In a radio frequency power amplifier, two amplifier branches have narrow operating frequency bands and operate on frequency band A and frequency band B, respectively, while the other amplifier branch is designed to have a wide frequency band and operates on frequency band A+B. The radio frequency power amplifier further includes an inter-frequency power divider circuit and two circulators. The inter-frequency power divider circuit performs inter-frequency power division on the output signal of the wideband amplifier branch to output two narrowband signals, which are then power-combined by the circulator and output. Based on the technical solution of the present application, a wideband problem is converted into a narrowband problem, and a PA with a narrow bandwidth is used for implementation, thereby improving PA efficiency. The wideband amplifier branch also provides a power sharing function, thereby implementing high-power wideband signal processing. Furthermore, a narrowband isolator is used at the lower level of each circulator, eliminating the need for a wideband isolator and reducing the difficulty of isolator design.

[0009] In this application, the type of the circulator port connected to the first inter-frequency power dividing circuit is not particularly limited. In this specification, the type of the circulator port refers to either an isolation port or an input port. The first inter-frequency power dividing circuit may be connected to the isolation port of the circulator or to the input port of the circulator. Several possible embodiments are described below.

[0010] In a possible implementation, the output end of the first amplifier branch is connected to an isolated port of the first circulator. The first output end of the first frequency power divider circuit is connected to an input port of the first circulator. The output end of the second amplifier branch is connected to an isolated port of the second circulator. And, the second output end of the first frequency power divider circuit is connected to an input port of the second circulator. Because the amplifier branches are connected to the isolated ports of the circulators, the output load of the amplifier branches remains unchanged, which facilitates independent design and can provide a relatively wide operating bandwidth.

[0011] In a possible embodiment, the output of the first amplifier branch is connected to the input port of the first circulator. The first output of the first inter-frequency power divider circuit is connected to the isolated port of the first circulator. The output of the second amplifier branch is connected to the input port of the second circulator. And, the second output of the first inter-frequency power divider circuit is connected to the isolated port of the second circulator. Because the first inter-frequency power divider circuit is connected to the isolated port of the circulator, the output load of the first inter-frequency power divider circuit remains unchanged, facilitating independent design of the third amplifier branch and the first inter-frequency power divider circuit.

[0012] In a possible embodiment, the output of the first amplifier branch is connected to the input port of the first circulator, the first output of the first frequency power divider circuit is connected to the isolated port of the first circulator, the output of the second amplifier branch is connected to the isolated port of the second circulator, and the second output of the first frequency power divider circuit is connected to the input port of the second circulator.

[0013] In a possible embodiment, the output of the first amplifier branch is connected to an isolated port of the first circulator, the first output of the first frequency power divider circuit is connected to an input port of the first circulator, the output of the second amplifier branch is connected to an input port of the second circulator, and the second output of the first frequency power divider circuit is connected to an isolated port of the second circulator.

[0014] In this application, the specific implementation of each amplifier branch is not particularly limited. For example, the first amplifier branch, the second amplifier branch, and the third amplifier branch may be any one of the following: a single transistor PA, a Doherty PA, a Chireix PA, a switched-mode regulated Doherty PA, a load modulation balanced amplifier LMBA, or a circulator load modulation amplifier CLMA.

[0015] Some specific implementations of each amplification branch are described below respectively.

[0016] In a first embodiment, the first amplification branch, the second amplification branch, and the third amplification branch each include a single transistor PA, where the single transistor PA included in the first amplification branch is a first carrier PA, the single transistor PA included in the second amplification branch is a second carrier PA, and the single transistor PA included in the third amplification branch is a Peak PA.

[0017] In a second embodiment, the first amplification branch and the second amplification branch each include a Doherty PA, the third amplification branch includes a single transistor PA, and the single transistor PA included in the third amplification branch is a Peak PA.

[0018] In a third embodiment, the first amplification branch, the second amplification branch, and the third amplification branch each include a Doherty PA.

[0019] As described above, three implementations of input signal paths have been described. An implementation for one signal path will be described below. In a possible implementation, the radio frequency power amplifier further includes a second inter-frequency power dividing circuit, a power divider, and a phase compensation network. A first output end of the power divider is connected to an input end of the second inter-frequency power dividing circuit, a first output end and a second output end of the second inter-frequency power dividing circuit are connected to a first amplification branch and a second amplification branch, respectively, a second output end of the power divider is connected to a first end of the phase compensation network, and a second end of the phase compensation network is connected to a third amplification branch.

[0020] Based on the above-described method for one input signal path, an embodiment for one output signal path will be described below. In a possible embodiment, the radio frequency power amplifier further includes a third inter-frequency power dividing circuit, where the output end of the first circulator and the output end of the second circulator are respectively connected to the first input end and the second input end of the third inter-frequency power dividing circuit, and the third inter-frequency power dividing circuit outputs a signal obtained through power combining.

[0021] As described above, a radio frequency power amplifier having three input signal paths has been described. Implementations of the radio frequency power amplifier supporting a larger number of input signal paths will be described below. The number of input signal paths is not particularly limited in this application. In a possible implementation, the radio frequency power amplifier further includes a fourth amplifier branch and a third circulator. The third amplifier branch operates in frequency band A, frequency band B, and frequency band C. The input end of the fourth amplifier branch is configured to connect to the fourth signal path. The output end of the fourth amplifier branch and the third output end of the first inter-frequency power divider circuit are respectively connected to different ports of the third circulator, and the first inter-frequency power divider circuit is further configured to output a frequency band C signal. The third circulator is configured to perform power combining on the frequency band C signal output by the fourth amplifier branch and the frequency band C signal output by the first inter-frequency power divider circuit, and then output.

[0022] The radio frequency power amplifier provided above can operate in both frequency division duplex mode and time division duplex mode. An example of the implementation of the time division duplex mode is described below. Switching between the signal transmission channel and the signal reception channel can be realized by adding two switches.

[0023] In a first embodiment, the radio frequency power amplifier further includes a first switch and a second switch. The antenna port of the first switch is connected to the isolation port of the first circulator, the receive port of the first switch is connected to the corresponding receive channel, and the transmit port of the first switch is connected to the output end of the first amplification branch. The antenna port of the second switch is connected to the isolation port of the second circulator, the receive port of the second switch is connected to the corresponding receive channel, and the transmit port of the second switch is connected to the second amplification branch.

[0024] In a second embodiment, the radio frequency power amplifier further includes a first switch and a second switch, the antenna port of the first switch is connected to the isolation port of the first circulator, the receive port of the first switch is connected to the corresponding receive channel, and the transmit port of the first switch is connected to the first output end of the first inter-frequency power divider circuit, the antenna port of the second switch is connected to the isolation port of the second circulator, the receive port of the second switch is connected to the corresponding receive channel, and the transmit port of the second switch is connected to the second output end of the first inter-frequency power divider circuit.

[0025] The present application further provides a remote radio unit including the radio frequency power amplifier described above, and further including a duplexer, wherein one end of the radio frequency power amplifier is connected to the duplexer.

[0026] Furthermore, the present application provides a base station including the above-described remote radio unit, and further including an antenna, wherein the remote radio unit is connected to the antenna, and the remote radio unit is configured to process received signals and transmitted signals of the antenna.

[0027] The present application has at least the following advantages:

[0028] The radio frequency power amplifier includes three amplifier branches, two of which have narrow operating frequency bands and operate on frequency band A and frequency band B, respectively, and the other amplifier branch is designed to have a wide frequency band and operates on frequency band A+B. That is, the operating frequency bands of the other amplifier branches cover frequency band A and frequency band B. The radio frequency power amplifier further includes an inter-frequency power divider circuit and two circulators. The inter-frequency power divider circuit can perform inter-frequency power division on the output signals of the wideband amplifier branches to output two narrowband signals, which are output after being power combined by the circulators for the output signals of each narrowband amplifier branch. In other words, the technical solution provided in this application converts a wideband problem into a narrowband problem, and some amplifier branches in the radio frequency power amplifier can be implemented by PAs with narrow bandwidths, thereby improving PA efficiency. The wideband amplifier branch provides a power distribution function, and the narrowband circulator, in cooperation with the frequency power divider circuit, performs power synthesis based on each frequency band to output multiple narrowband signal paths, so that the entire RF power amplifier can process high-power wideband signals. Also, narrowband isolators can be used at the lower level of each circulator, which eliminates the need for wideband isolators and reduces the difficulty of isolator design. [Brief explanation of the drawings]

[0029] [Figure 1] FIG. 1 is a diagram illustrating an RRU. [Figure 2] FIG. 1 illustrates a radio frequency power amplifier according to an embodiment of the present application. [Figure 3] FIG. 2 illustrates another radio frequency power amplifier according to an embodiment of the present application. [Figure 4] FIG. 1 illustrates yet another radio frequency power amplifier according to an embodiment of the present application. [Figure 5] FIG. 1 illustrates yet another radio frequency power amplifier according to an embodiment of the present application. [Figure 6] FIG. 1 illustrates yet another radio frequency power amplifier according to an embodiment of the present application. [Figure 7] FIG. 1 illustrates yet another radio frequency power amplifier according to an embodiment of the present application. [Figure 8] FIG. 8 is a diagram showing currents corresponding to FIG. 7 according to an embodiment of the present application. [Figure 9] FIG. 8 is a diagram illustrating voltages corresponding to FIG. 7 according to an embodiment of the present application. [Figure 10] FIG. 8 is a diagram illustrating impedances corresponding to FIG. 7 according to an embodiment of the present application. [Figure 11] FIG. 8 is a curve diagram showing efficiency corresponding to FIG. 7 according to one embodiment of the present application. [Figure 12] FIG. 1 illustrates yet another radio frequency power amplifier according to an embodiment of the present application. [Figure 13] FIG. 13 is a diagram showing currents corresponding to FIG. 12 according to an embodiment of the present application. [Figure 14] 13 is a diagram showing voltages corresponding to FIG. 12 according to one embodiment of the present application. [Figure 15] FIG. 13 is a diagram illustrating impedances corresponding to FIG. 12 according to an embodiment of the present application. [Figure 16] FIG. 13 is a curve diagram showing efficiency corresponding to FIG. 12 according to an embodiment of the present application. [Figure 17] FIG. 1 illustrates yet another radio frequency power amplifier according to an embodiment of the present application. [Figure 18] FIG. 18 is a diagram showing the efficiency corresponding to FIG. 17 according to one embodiment of the present application. [Figure 19] FIG. 1 illustrates a radio frequency power amplifier according to an embodiment of the present application. [Figure 20] FIG. 2 illustrates another radio frequency power amplifier according to an embodiment of the present application. [Figure 21] FIG. 1 illustrates a single-input multiple-output radio frequency power amplifier according to an embodiment of the present application. [Figure 22]FIG. 1 illustrates a single-input single-output radio frequency power amplifier according to an embodiment of the present application. [Figure 23] FIG. 1 illustrates yet another radio frequency power amplifier according to an embodiment of the present application. [Figure 24] FIG. 1 illustrates yet another radio frequency power amplifier according to an embodiment of the present application. [Figure 25] 1 illustrates a base station according to an embodiment of the present application; DETAILED DESCRIPTION OF THE INVENTION

[0030] With reference to the accompanying drawings in the embodiments of the present application, the technical solutions in the embodiments of the present application are described below.

[0031] The terms "first," "second," and the like below are for descriptive purposes only and are not to be understood as an indication or suggestion of relative importance or an implicit indication of the quantity of technical features. As such, features qualified by the terms "first," "second," and the like may explicitly or implicitly include one or more features. In the specification of this application, unless otherwise specified, "plurality" means two or more than two.

[0032] In this application, unless otherwise specified and indicated, the term "connected" should be understood in a broad sense. For example, "connected" may be permanently connected, detachably connected, integral, directly connected, or indirectly connected using an intermediate medium.

[0033] In order to enable those skilled in the art to better understand the technical solutions provided in the embodiments of the present application, the application scenarios of the technical solutions will be first described below with reference to the accompanying drawings.

[0034] The radio frequency power amplifier provided in the embodiment of the present application will be described by using an example applied to a Radio Remote Unit (RRU) in a base station. It should be noted that the radio frequency power amplifier in the embodiment of the present application is not limited to being applied to an RRU.

[0035] The main functions of an RRU include intermediate frequency processing, radio frequency processing, signal duplication, and the like. A radio frequency power amplifier is an important part of an RRU. The radio frequency signal is amplified by the radio frequency power amplifier and then transmitted through an antenna. The embodiments of the present application are particularly related to the radio frequency power amplifier in the RRU. For ease of explanation, the radio frequency power amplifier will be abbreviated as "radio frequency power amplifier" hereinafter.

[0036] FIG. 1 is a diagram illustrating an RRU.

[0037] The RRU 1000 provided in this embodiment of the present application may be applied to a wireless communication base station. In addition to the RRU 1000, the base station may further include other components, such as an antenna feeding system and a baseband unit (BBU). The antenna feeding system may include multiple antennas. Two antennas are listed below as an example. Specifically, a first antenna ANT1 and a second antenna ANT2 are configured to transmit or receive signals.

[0038] The RRU 1000 includes a radio frequency power amplifier, a low noise amplifier (LNA), a duplexer 100, a transmit signal processing unit TX, a receive signal processing unit RX, and a common public radio interface (CPRI).

[0039] The duplexer 100 is connected to an antenna feeding system, and the CPRI interface is connected to a BBU.

[0040] The number of radio frequency power amplifiers may be multiple based on the number of transmission paths, i.e., may include radio frequency power amplifier 201 to radio frequency power amplifier 20m. Similarly, the number of LNAs may be multiple based on the number of reception channels, i.e., may include LNA1 to LNAn.

[0041] In the signal transmission direction of the RRU 1000, the radio frequency signal of the transmitting signal processing unit TX is amplified by the radio frequency power amplifier and then transmitted to the antenna feeding system through the duplexer 100.

[0042] In the signal receiving direction of the RRU 1000, the radio frequency signal received by the antenna in the antenna feeding system is transmitted to the LNA via the duplexer 100, and the signal amplified by the LNA is transmitted to the received signal processing unit RX for processing.

[0043] In practical applications, an isolator needs to be connected to the lower level of a radio frequency power amplifier. When the operating frequency is wide, the radio frequency power amplifier and the isolator connected to the lower level need to support the corresponding operating bandwidth. However, designing a wideband isolator is difficult, especially in ultra-wideband scenarios. Furthermore, designing a wideband radio frequency power amplifier is also difficult and usually suffers from technical problems such as reduced efficiency and other performance degradation.

[0044] To solve the aforementioned problem of difficulty in designing wideband isolators and wideband radio frequency power amplifiers, the technical solution provided in this application converts the wideband problem into a narrowband problem. Some amplification branches in the radio frequency power amplifier are designed for narrowband to improve PA efficiency. Other amplification branches in the radio frequency power amplifier are designed for wideband to provide power sharing. Furthermore, a narrowband circulator, together with an inter-frequency power divider circuit, performs power synthesis on the signals output by the wideband amplification branches and the narrowband amplification branches, and outputs signals based on each frequency band. Narrowband isolators are used at lower levels of each circulator, which eliminates the need for wideband isolators and reduces the difficulty in designing the isolators.

[0045] In order to enable those skilled in the art to better understand the technical solutions provided in the embodiments of the present application, the following specific descriptions are provided with reference to the accompanying drawings.

[0046] The radio frequency power amplifier provided in the embodiment of the present application does not particularly limit the number of input signal paths, and the number may be, for example, N, where N is an integer equal to or greater than 3. The radio frequency power amplifier may include N amplification branches, N-1 circulators, and at least one inter-frequency power division circuit.

[0047] Furthermore, the radio frequency power amplifier provided in the embodiments of the present application may alternatively operate in a scenario with only one input signal path, or in a scenario with only two input signal paths. In order to facilitate understanding of the technical solutions provided in the embodiments of the present application, an example including three input signal paths will be first used for explanation below. Figure 2 is a diagram showing a radio frequency power amplifier according to an embodiment of the present application.

[0048] The radio frequency power amplifier provided in this embodiment includes: a first amplifier branch AmpA, a second amplifier branch AmpB, a third amplifier branch AmpC, a first circulator CircA, a second circulator CircB, and a first inter-frequency power dividing circuit Dipl.

[0049] The input terminal of the first amplification branch AmpA is configured to connect to the first path of the signal Input1, the input terminal of the second amplification branch AmpB is configured to connect to the second path of the signal Input2, and the input terminal of the third amplification branch AmpC is configured to connect to the third path of the signal Input3.

[0050] The output of the third amplifier branch AmpC is connected to the input of the first inter-frequency power dividing circuit Dipl.

[0051] The operating frequency band of the first amplifier branch AmpA is frequency band AB and A, the operating frequency band of the second amplifier branch AmpB is frequency band BB and B, and the operating frequency band of the third amplifier branch AmpC is frequency band A and frequency band B (Band A+B). That is, the operating frequency band of the third amplifier branch AmpC covers both frequency band A and frequency band B. The operating frequency band of the first circulator is frequency band AB and A, and the operating frequency band of the second circulator is frequency band BB and B. The first inter-frequency power division circuit Dipl is configured to: perform inter-frequency power division on the output signal of the third amplifier branch AmpC; and output frequency band A signals and frequency band B signals corresponding to the Band A signals and Band B signals, respectively.

[0052] The output terminal of the first amplifier branch AmpA and the first output terminal of the first inter-frequency power divider circuit Dipl are respectively connected to different ports of a first circulator CircA. The first circulator CircA is configured to perform power combining of the frequency band A signal output from the first amplifier branch AmpA and the frequency band A signal output from the first inter-frequency power divider circuit Dipl, and then output the frequency band A signal from the output terminal Output A.

[0053] The output terminal of the second amplifier branch AmpB and the second output terminal of the first inter-frequency power divider circuit Dipl are respectively connected to different ports of a second circulator CircB. The second circulator CircB is configured to perform power combining of the frequency band B signal output from the second amplifier branch AmpB and the frequency band B signal output from the first inter-frequency power divider circuit Dipl, and then output the frequency band B signal from the output terminal Output B.

[0054] The first circulator CircA and the lower level isolator may be designed as one device to reduce the area and cascaded insertion loss, and similarly, the second circulator CircB and the lower level isolator may be designed as one device to reduce the area and cascaded insertion loss.

[0055] Generally, the characteristic impedance Z0_A of the first circulator CircA and the characteristic impedance Z0_B of the second circulator CircB are both 50 Ω (Ohm).

[0056] In the embodiment of the present application, the type of the circulator port connected to the first inter-frequency power division circuit Dipl is not particularly limited. In this specification, the type of the circulator port refers to an isolation port or an input port. For example, the first inter-frequency power division circuit Dipl may be connected to the isolation port of the circulator or the input port of the circulator.

[0057] 2, based on the radio frequency power amplifier provided in this embodiment of the present application, a three-path signal is input and a two-path signal is output, the bandwidth that can process the input signal is frequency band A+B, and the bandwidth of the two-path output signal is frequency band A and frequency band B, respectively. In this way, an isolator whose operating frequency band is frequency band A can be connected to the lower level of the first circulator, and an isolator whose operating frequency band is frequency band B can be connected to the lower level of the second circulator. In other words, in this application, the fact that the input signal is on frequency band A+B does not mean that an isolator of frequency band A+B needs to be used on the lower level; instead, an isolator with a narrow frequency band can be used to reduce the design difficulty of the isolator.

[0058] The first and second amplifier branches AmpA and AmpB can both be designed as narrow-band PAs, reducing their design difficulty and thereby facilitating higher efficiency. The third amplifier branch AmpC, designed as a wide-band PA, provides a power sharing function.

[0059] The frequency band A and frequency band B described in the above-mentioned embodiments of the present application may be a single frequency band or multiple frequency bands. For example, frequency band A may be frequency band A1+frequency band A2, or frequency band A may be frequency band A1+frequency band A2+frequency band A3. Similarly, frequency band B may be frequency band B1+frequency band B2, or frequency band B may be frequency band B1+frequency band B2+frequency band B3.

[0060] Frequency band A and frequency band B are different frequency bands. In other words, frequency band A and frequency band B do not have overlapping frequency bands. That is, the two frequency bands do not have overlapping frequencies. The frequency of frequency band A may be higher than the frequency of frequency band B, or the frequency of frequency band A may be lower than the frequency of frequency band B. This is not particularly limited in the embodiments of the present application. For ease of explanation, the operating principle of the radio frequency power amplifier provided in the embodiments of the present application will be described below through an example in which the frequency of frequency band A is lower than the frequency of frequency band B.

[0061] When the radio frequency power amplifier operates only in frequency band A, no signal is input to AmpB and AmpB is in a closed state. In this case, only AmpA and AmpC operate, and both AmpA and AmpC operate in frequency band A. A signal in frequency band A is input to both Input1 and Input3, and a signal in frequency band A is output from Output A.

[0062] When the radio frequency power amplifier operates only in frequency band B, no signal is input to AmpA and AmpA is closed. In this case, only AmpB and AmpC operate, and both operate in frequency band B. A signal in frequency band B is input to both Input2 and Input3, and a signal in frequency band B is output from Output B.

[0063] When a radio frequency power amplifier operates in both frequency band A and frequency band B, AmpA, AmpB, and AmpC all operate. AmpA operates in frequency band A, AmpB operates in frequency band B, and AmpC operates in frequency band A+B. Input1 inputs a signal in frequency band A, Input2 inputs a signal in frequency band B, and Input3 inputs a signal in frequency band A+B. Output A outputs a signal in frequency band A, and Output B outputs a signal in frequency band B.

[0064] Furthermore, to improve the performance of the RF power amplifier, Z0_A and / or Z0_B can be optimized. For example, a high-power RF power amplifier can be designed with a low impedance. In this case, impedance transformation circuits only need to be placed at the two circulator output ports, for example, transforming Z0_A to 50 Ω and transforming Z0_B to 50 Ω.

[0065] In Fig. 2, the specific port of the circulator connected to the first inter-frequency power division circuit is not limited. Based on the embodiment in Fig. 2, a specific embodiment will be described with reference to Fig. 3. In Fig. 3, an example in which the input port of the circulator is connected to the first inter-frequency power division circuit will be described.

[0066] FIG. 3 is a diagram illustrating another radio frequency power amplifier according to an embodiment of the present application.

[0067] In this embodiment, the first output end of the first inter-frequency power dividing circuit Dipl is connected to the input port of the first circulator CircA, and the first amplification branch AmpA is connected to the isolation port of the first circulator CircA.

[0068] Similarly, the second output end of the first inter-frequency power dividing circuit Dipl is connected to the input port of the second circulator CircB, and the second amplification branch AmpB is connected to the isolation port of the second circulator CircB.

[0069] Because AmpA and AmpB are connected to the isolated ports of the circulator, the output loads of AmpA and AmpB remain unchanged, which facilitates independent design and can have a relatively wide operating bandwidth.

[0070] 3 illustrates an example in which the first and second amplifier branches are connected to the isolated ports of the circulator. Another embodiment in which the output of the first inter-frequency power dividing circuit is connected to the isolated port of the circulator will be described below.

[0071] FIG. 4 is a diagram illustrating yet another radio frequency power amplifier according to an embodiment of the present application.

[0072] In this embodiment, the first output end of the first inter-frequency power dividing circuit Dipl is connected to the isolation port of the first circulator CircA, and the first amplification branch AmpA is connected to the input port of the first circulator CircA.

[0073] Similarly, the second output end of the first inter-frequency power dividing circuit Dipl is connected to the isolated port of the second circulator CircB, and the second amplification branch AmpB is connected to the input port of the second circulator CircB.

[0074] Since the first inter-frequency power dividing circuit is connected to the isolated port of the circulator, the output load of the first inter-frequency power dividing circuit remains unchanged, which makes it easy to design the third amplifier branch AmpC and the first inter-frequency power dividing circuit independently. Also, when AmpA and AmpB operate first, the insertion loss at low power is relatively small, and the efficiency at low power is relatively high.

[0075] 3 and 4, the port types of the circulators connected to the first and second amplifier branches are the same. Alternatively, it should be understood that the port types of the circulators connected to the first and second amplifier branches may be different. For example, the first amplifier branch is connected to the isolation port of the first circulator, and the second amplifier branch is connected to the input port of the second circulator. This is described in detail below with reference to the accompanying drawings.

[0076] FIG. 5 illustrates yet another radio frequency power amplifier according to an embodiment of the present application.

[0077] In this embodiment, the first output end of the first inter-frequency power dividing circuit Dipl is connected to the input port of the first circulator CircA, and the first amplification branch AmpA is connected to the isolation port of the first circulator CircA.

[0078] The second output end of the first inter-frequency power dividing circuit Dipl is connected to the isolation port of the second circulator CircB, and the second amplification branch AmpB is connected to the input port of the second circulator CircB.

[0079] FIG. 6 is a diagram illustrating yet another radio frequency power amplifier according to an embodiment of the present application.

[0080] In this embodiment, the first output end of the first inter-frequency power dividing circuit Dipl is connected to the isolation port of the first circulator CircA, and the first amplification branch AmpA is connected to the input port of the first circulator CircA.

[0081] The second output end of the first inter-frequency power dividing circuit Dipl is connected to the input port of the second circulator CircB, and the second amplification branch AmpB is connected to the isolation port of the second circulator CircB.

[0082] In the embodiment of the present application, the specific type of PA included in each amplification branch is not particularly limited. The first amplification branch, the second amplification branch, and the third amplification branch are each one of the following types, but are not limited to the following types: These are the single transistor PA, Doherty PA, Kireis PA, switched-mode regulated Doherty PA, load modulated balanced amplifier (LMBA), or circulator load modulated amplifier (CLMA).

[0083] First, with reference to the accompanying drawings, an implementation in which all three amplifier branches are single transistor PAs will be described below.

[0084] FIG. 7 illustrates yet another radio frequency power amplifier according to one embodiment.

[0085] The first amplification branch AmpA includes a single transistor PA, which is called the first carrier PA and is represented by MainA.

[0086] The second amplification branch AmpB includes a single transistor PA, which is called a second carrier PA and is represented by MainB.

[0087] The third amplification branch AmpC includes a single transistor PA, which is called PeakPA and represented by Peak.

[0088] AmpA and AmpB act before AmpC.

[0089] Main A operates on Band A, the Main B PA unit operates on Band B, and Peak operates on Band A+B. Peak provides power sharing functionality.

[0090] When the radio frequency power amplifier operates only on Band A, Main B is in a closed state, no signal is input to Main B, and Main B receives a class C bias. In this case, only Main A and Peak operate, Main A operates in class AB or class B, and Peak operates in class C. The operation mechanism of Main A and Peak is the SCLMA operation mode.

[0091] When the input signal power of the RF power amplifier is low, only Main A operates until the power reaches saturation. Then Peak switches on and Main A remains saturated until both Main A and Peak reach saturation.

[0092] When the radio frequency power amplifier operates only on Band B, Main A is in a closed state, no signal is input to Main A, and Main A receives a class C bias. In this case, Main B and Peak operate, Main B operates in class AB or class B, and Peak operates in class C. In this case, the operation mechanism of Main B and Peak is the same as that described above.

[0093] When the radio frequency power amplifier operates on both Band A and Band B, the curves of current, voltage, impedance, and efficiency of the radio frequency power amplifier are shown in Figures 8 to 11. In each curve, "main" refers to either Main A or Main B. Figures 8 to 11 all correspond to a scenario where the saturated power ratio of Main and Peak is equal to 1:3.

[0094] 8 to 11, the horizontal axis represents normalized voltage (V0 / Vdd), and the normalization method is the ratio of the output voltage V0 to the drain bias voltage Vdd in the PA. The vertical axis in Fig. 8 represents output current (Current), the vertical axis in Fig. 9 represents voltage (Voltage), the vertical axis in Fig. 10 represents impedance (Impedance), and the vertical axis in Fig. 11 represents efficiency (Efficiency).

[0095] In Fig. 8, Imain is the Main output current and Ipeak is the Peak output current. As can be seen from the current diagram shown in Fig. 8, Imain reaches current saturation earlier than IPeak.

[0096] In Figure 9, Vmain is the Main output voltage and Vpeak is the Peak output voltage. As can be seen from the voltage diagram shown in Figure 9, Vmain reaches voltage saturation earlier than Vpeak.

[0097] As can be seen from the impedance curves shown in FIG. 10, the load pull ratio of Main is 1, i.e. the load Zmain of Main remains unchanged.

[0098] In the efficiency curve diagram in FIG. 11, Main reaches saturation at the first high efficiency point, and Main and Peak reach saturation at the second high efficiency point.

[0099] When the radio frequency power amplifier operates on both Band A and Band B, Main A, Main B, and Peak all operate. In this case, Main A and Main B both operate in Class AB or Class B, Peak operates in Class C, Main A operates on Band A, Main B operates on Band B, and Peak operates on both Band A and Band B. After passing through the first inter-frequency power division circuit Dipl, the Peak output individually forms the SCLMA operating mode, including Main A and Main B.

[0100] All the PAs in the three amplifying branches of the radio frequency power amplifier shown in Figure 7 are realized by single transistor PAs. An alternative implementation is described below.

[0101] FIG. 12 is a diagram illustrating yet another radio frequency power amplifier according to an embodiment of the present application.

[0102] In the radio frequency power amplifier provided in this embodiment, the first and second amplification branches are Doherty PAs, and the third amplification branch is a single transistor PA.

[0103] The third amplification branch is called Peak PA and is represented by Peak2.

[0104] All the single transistor PAs in FIG. 7 are replaced with Doherty (DHT for short) PAs, and the rest of the configuration remains unchanged, which will not be described again here.

[0105] 12 is used as an example. The DHT PA includes: a first power divider SplA, a carrier PA Main A, and a Peak PA Peak1 A. Furthermore, the DHT PA includes: a phase compensation network CompA, an impedance inversion network INTA, and a matching network MNA.

[0106] The first path signal Input1 is input to the input port of the first power divider SplA, and after being power-divided by the first power divider SplA, the first path signal Input1 is input to Main A and Peak1 A. Here, the signal output by Main A is processed by INTA and then combined with the signal output by Peak1 A, and then input to the isolation port 3 of the first circulator CircA via MNA.

[0107] In Fig. 12, the architecture of the DHT PA in the second amplification branch is the same as the architecture of the DHT PA in the first amplification branch, and the path of the second path input signal Input2 in Fig. 12 is the same as the path of Input1, and the details will not be described again in this specification.

[0108] If AmpA and AmpB are implemented using the Doherty PA architecture, AmpC is implemented using a single-transistor PA, and AmpA and AmpB operate before AmpC, Input1 is power-divided by SplA and then split into two paths. One path is connected to MainA, and the other path is connected to Peak1A via CompA. MainA and Peak1A are combined by INTA and MNA to form DHT A, which is connected to isolated port 3 of circulator CirA. DHT A operates on Band A.

[0109] Input2 is power-divided by SplB and then split into two paths. One path is connected to Main B, and the other path is connected to Peak1 B via CompB. Main B and Peak1 B are combined by INTB and MNB to form DHT B, which is connected to isolated port 3 of circulator CircB. DHT B operates on Band B.

[0110] Input3 is connected to the input terminal of Peak2. Peak2 operates on both Band A and Band B and provides power sharing function. After power division by Dipl, the two output paths of Dipl output Band A and Band B signals, respectively, and these paths are connected to input port 1 of CircA and input port 1 of CircB. Port 2 of CircA and port 2 of CircB are output ports, and these ports output Band A and Band B signals, respectively.

[0111] When the radio frequency power amplifier operates only on Band A, Main B and Peak1 B are closed, no signal is input to Input2, and Main B and Peak1 B are biased in class C. In this case, only Main A, Peak1 A, and Peak 2 operate. Main A is biased in class AB or class B, Peak1 A is biased in shallow class C, and Peak2 is biased in deep class C.

[0112] When the input signal power is low, only Main A operates until the voltage of Main A saturates. Then Peak1 A starts operating, and load modulation is performed on Main A. Main A maintains voltage saturation until Peak1 A also saturates. In this case, Main A and Peak1 A reach current saturation. This is the mechanism of DHT pull. Then Peak2 starts operating, and Main A and Peak1 A maintain saturation until Peak2 saturates. In this case, the SCLMA operating mode is enabled.

[0113] When the radio frequency power amplifier operates only on Band B, Main A and Peak1 A are closed, no signal is input to Input1, and Main A and Peak1 A are biased under class C. In this case, only Main B, Peak1 B, and Peak2 operate. The operating mechanism is the same as when the radio frequency power amplifier operates only on Band A.

[0114] FIG. 13 is a diagram illustrating currents corresponding to scenarios in which the radio frequency power amplifier in FIG. 12 operates on only Band A or Band B, according to an embodiment of the present application.

[0115] FIG. 14 is a diagram illustrating voltages corresponding to scenarios in which the radio frequency power amplifier in FIG. 12 operates on only Band A or Band B, according to an embodiment of the present application.

[0116] 13 and 14, the horizontal axis represents normalized voltage (V0 / Vdd), the vertical axis in Fig. 13 represents current, and the vertical axis in Fig. 14 represents voltage.

[0117] FIG. 15 is a diagram illustrating impedances corresponding to scenarios in which the radio frequency power amplifier in FIG. 12 operates on only Band A or Band B, according to an embodiment of the present application.

[0118] FIG. 16 is a curve diagram illustrating the efficiency in a scenario in which the radio frequency power amplifier in FIG. 12 operates on only Band A or Band B, according to an embodiment of the present application.

[0119] The horizontal axis in FIG. 15 represents normalized voltage (V0 / Vdd), and the vertical axis in FIG. 15 represents impedance.

[0120] The horizontal axis in FIG. 16 represents output power, and the vertical axis in FIG. 16 represents efficiency.

[0121] 13 to 16, Main refers to Main A or Main B, and Peak1 refers to Peak1 A or Peak1 B. Each curve is a curve when the saturated power ratio is MAiN:Peak1:Peak2=1:1:6.

[0122] As can be seen from FIG. 13, Imain reaches current saturation earlier than Ipeak1, and Ipeak1 reaches current saturation earlier than Ipeak2.

[0123] 14, Main reaches voltage saturation first, then Peak1 reaches voltage saturation, and finally Peak2 reaches voltage saturation. In other words, Vmain reaches voltage saturation earlier than Vpeak1, Vpeak1 reaches voltage saturation earlier than Vpeak2, and finally Vpeak2 reaches voltage saturation.

[0124] Figure 16 is a curve diagram showing the efficiency in a scenario where the saturated power ratio is Main:Peak1:Peak2=100W:100W:600W. As can be seen from the efficiency curve diagram in Figure 16, there are three high efficiency points, which can reduce the size of the lower region.

[0125] As can be seen from FIG. 16, the radio frequency power amplifier can implement a 12 dB back-off design.

[0126] When the radio frequency power amplifier operates on both Band A and Band B, DHT A, DHT B, and Peak2 all operate. In DHT A, Main A receives a Class AB or Class B bias, and Peak1 A receives a shallow Class C bias. In DHT B, Main B receives a Class AB or Class B bias, Peak1 B receives a shallow Class C bias, and Peak2 receives a deep Class C bias. DHT A operates on Band A, DHT B operates on Band B, and Peak2 operates on both Band A and Band B. After passing through the first inter-frequency power division circuit Dipl, the output of Peak2 individually forms the SCLMA operating mode, including DHT A and DHT B.

[0127] 12 uses an example in which the output end of the first inter-frequency power divider circuit is connected to the input port of the circulator. The following description uses another example in which the output end of the first inter-frequency power divider circuit is connected to the isolated port of the circulator, and the PAs in the first amplifying branch, the second amplifying branch, and the third amplifying branch are all Doherty PAs.

[0128] FIG. 17 illustrates yet another radio frequency power amplifier according to an embodiment of the present application.

[0129] In the radio frequency power amplifier provided in this embodiment, the first amplification branch, the second amplification branch, and the third amplification branch are Doherty PAs.

[0130] When AmpA, AmpB, and AmpC are all implemented by DHT PAs and AmpA and AmpB operate before AmpC, Input1 is power-divided by SplA and then split into two paths. One path is connected to MainA, and the other path is connected to Peak1A via a phase compensation network CompA. The output of MainA passes through INTA and is combined with the output of a PA called Peak1A, and then the combined output passes through an impedance transformation network MNA and is connected to input port 1 of the first circulator CircA.

[0131] Input2 is power-divided by SplB and then split into two paths. One path is connected to MainB, and the other path is connected to Peak1B via a phase compensation network CompB. The output of MainB passes through INTB and is combined with the output of Peak1B, and then the combined output passes through an impedance transformation network MNB and is connected to input port 1 of the second circulator CircB.

[0132] Input3 is power-divided by Sp13 and then split into two paths. One path is connected to Peak2C, and the other path passes through a phase compensation network CompC and then connects to Peak3C. The output of Peak2C passes through INTC and is combined with the output of Peak3C. The combined output then passes through an impedance transformation network MNC and is connected to the first inter-frequency power divider circuit Dipl. After passing through the first inter-frequency power divider circuit Dipl, two paths are output, which output the Band A signal and the Band B signal, respectively. The two paths output by Dipl are connected to isolation port 3 of CircA and isolation port 3 of CircB, respectively. Output port 2 of CircA and output port 2 of CircB output the Band A signal and the Band B signal, respectively.

[0133] When the radio frequency power amplifier operates only on Band A, AmpB is closed. In this case, Main B and Peak1 B in AmpB are biased in class C. When AmpA and AmpC are operating, Main A is biased in class AB or class B, and Peak1 A, Peak2 C, and Peak3 C are biased in class C.

[0134] Fig. 18 is a curve diagram showing efficiency when the saturated power ratio of Main A, Peak1 A, Peak2 C, and Peak3 C is 10 W:40 W:53.3 W:106.7 W. The horizontal axis in Fig. 18 represents output power, and the vertical axis in Fig. 18 represents efficiency.

[0135] As can be seen from FIG. 18, the radio frequency power amplifier can achieve a power back-off of approximately 13 dB.

[0136] When the radio frequency power amplifier operates only on Band B, AmpA is closed. In this case, Main A and Peak1 A in AmpA receive Class C bias, and AmpB and AmpC operate. In this case, Main B receives Class AB or Class B bias, and Peak1 B, Peak2 C, and Peak3 C receive Class C bias. The operating mechanism is the same as that described above.

[0137] When the radio frequency power amplifier operates on both Band A and Band B, AmpA, AmpB, and AmpC all operate. Main A and Main B receive Class AB or Class B bias, and the other inputs receive Class C bias. Input 1 inputs the Band A signal, Input 2 inputs the Band B signal, and Input 3 inputs the Band A+B signal. Output A outputs the Band A signal, and Output B outputs the Band B signal.

[0138] In the above-described embodiment, a radio frequency power amplifier having three input signal paths is described. An implementation of a radio frequency power amplifier having a larger number of input signal paths will be described below. In the embodiment of the present application, the number of input signal paths is not particularly limited. For ease of explanation, an example having four input signal paths will be used for description.

[0139] FIG. 19 is a diagram illustrating a radio frequency power amplifier according to an embodiment of the present application.

[0140] The difference between the radio frequency power amplifier provided in this embodiment and the radio frequency power amplifier in FIG. 3 is that the radio frequency power amplifier further includes a fourth amplification branch AmpD and a third circulator CircC.

[0141] The third amplification branch AmpC operates on frequency band A, frequency band B, and frequency band C. Frequency band C is different from either frequency band A or frequency band B. For example, in a possible implementation, the frequencies of frequency band A will be lower than the frequencies of frequency band B, which will be lower than the frequencies of frequency band C.

[0142] The input of the fourth amplification branch AmpD is arranged to be connected to the fourth path of the signal Input4.

[0143] The output terminal of the fourth amplifier branch AmpD and the third output terminal of the first inter-frequency power dividing circuit Dipl are respectively connected to different ports of the third circulator CircC. The first inter-frequency power dividing circuit Dipl is configured to perform inter-frequency power division on the signals output from the third amplifier branch AmpC, and thereafter to divide the signals into frequency band A signals, frequency band B signals, and frequency band C signals, i.e., the Band A signal, the Band B signal, and the Band C signal.

[0144] The third circulator CircC operates on frequency band C.

[0145] The third circulator CircC is configured to perform power combining of the frequency band C signal output from the fourth amplification branch AmpD and the frequency band C signal output from the first inter-frequency power division circuit Dipl, and then output.

[0146] As can be seen by comparing Figure 19 and Figure 3, the first inter-frequency power dividing circuit Dipl includes three output terminals, which respectively output signals of three different frequency bands, and the third amplification branch AmpC can process signals of a wider frequency band.

[0147] A radio frequency power amplifier can input four-path signals and output three different frequency band signals. Each output can be connected to a corresponding isolator, so that the corresponding isolator only needs to ensure that it can process signals of the corresponding frequency band, and the isolator does not need to operate over the entire operating frequency band. This can reduce the design difficulty of the isolator and can be implemented by an isolator with a narrow bandwidth.

[0148] The type of PA in Figure 19 is not particularly limited in the embodiments of the present application. The PA may be a single transistor PA, or may be a Doherty PA, a switched-mode Doherty PA, a Kireis PA, an LMBA, a CLMA, or the like.

[0149] In Fig. 19, the output terminal of the first inter-frequency power divider circuit Dipl is connected to the isolated port of the circulator. That is, the first output terminal of the first inter-frequency power divider circuit Dipl is connected to the isolated port 3 of the first circulator CircA. The second output terminal of the first inter-frequency power divider circuit Dipl is connected to the isolated port 3 of the second circulator CircB. The third output terminal CircA of the first inter-frequency power divider circuit Dipl is connected to the isolated port 3 of the third circulator CircC. This facilitates the independent design of the first inter-frequency power divider circuit Dipl and the third amplifier branch AmpC.

[0150] With reference to the accompanying drawings, an implementation in which the output end of the first inter-frequency power dividing circuit Dipl is connected to the input port of a circulator will be described below.

[0151] FIG. 20 is a diagram illustrating another radio frequency power amplifier according to an embodiment of the present application.

[0152] The difference between Figure 20 and Figure 19 is that in Figure 20, the first output terminal of the first inter-frequency power division circuit Dipl is connected to input port 1 of the first circulator CircA, the second output terminal CircA of the first inter-frequency power division circuit Dipl is connected to input port 1 of the second circulator CircB, and the third output terminal CircA of the first inter-frequency power division circuit Dipl is connected to input port 1 of the third circulator CircC.

[0153] The operation principle in FIGS. 19 and 20 is similar to that of the three input signal paths, and the details will not be described again in this specification.

[0154] The final-level power combining units in the radio frequency power amplifiers described in the above-mentioned embodiments of the present application are all circulators, which are suitable for high-power scenarios and can process signals with high power, so the radio frequency power amplifiers provided in the embodiments of the present application can be applied to high-power ultra-wideband scenarios.

[0155] In the above-mentioned embodiments, the radio frequency power amplifier is described by using the case of having multiple input signal paths and multiple output signal paths as an example. The radio frequency power amplifier provided in the embodiments of the present application can also be applied to a scenario with a single input signal path. The following description will be made with reference to the accompanying drawings.

[0156] FIG. 21 is a diagram illustrating a single-input multiple-output radio frequency power amplifier according to an embodiment of the present application.

[0157] The radio frequency power amplifier provided in this embodiment further includes: a second inter-frequency power dividing circuit Dipl2, a power divider Spl, and a phase compensation network Comp.

[0158] A first output terminal of the power divider Sp1 is connected to an input terminal of a second inter-frequency power dividing circuit Dipl2, a first output terminal and a second output terminal of the second inter-frequency power dividing circuit Dipl2 are connected to a first amplifier branch AmpA and a second amplifier branch AmpB, respectively. A second output terminal of the power divider Sp1 is connected to a first terminal of a phase compensation network Comp, and a second terminal of the phase compensation network Comp is connected to a third amplifier branch AmpC.

[0159] The input signal Input is power-divided by a power divider Spl, one path of which passes through a second inter-frequency power divider circuit Dipl2 and is connected to the input ports of AmpA and AmpB, respectively, and the other path output by the power divider Spl passes through a phase compensation network Comp and is connected to the input port of AmpC. As can be seen from this, this radio frequency power amplifier can also be applied to a scenario having only one input signal path.

[0160] The radio frequency power amplifiers described in the above embodiments are all of the multi-output type. A scenario in which the radio frequency power amplifier provided in the embodiments of the present application can alternatively be applied to a single-output type will be described below.

[0161] FIG. 22 is a diagram illustrating a single-input, single-output radio frequency power amplifier according to an embodiment of the present application.

[0162] Based on the radio frequency power amplifier provided in FIG. 21, the radio frequency power amplifier provided in this embodiment further includes a third inter-frequency power dividing circuit Dipl3.

[0163] The output terminal of the first circulator CircA and the output terminal of the second circulator CircB are connected to a first input terminal and a second input terminal of a third inter-frequency power dividing circuit Dipl3, respectively.

[0164] The third inter-frequency power divider circuit Dipl3 outputs the power-combined signal. Specifically, the output terminal Output of the third inter-frequency power divider circuit Dipl3 outputs the power-combined signal.

[0165] The radio frequency power amplifier provided in the above-mentioned embodiments can operate in Frequency Division Duplexing (FDD) mode and Time Division Duplex (TDD) mode, the TDD mode will be described in detail below with reference to the accompanying drawings.

[0166] FIG. 23 illustrates yet another radio frequency power amplifier according to an embodiment of the present application.

[0167] In FIG. 23, a first switch S1 and a second switch S2 are added based on FIG.

[0168] The antenna port ANTA of the first switch S1 is connected to the isolation port 3 of the first circulator CircA, the receive port RX1 of the first switch S1 is connected to the corresponding receive channel RXA, and the transmit port TX1 of the first switch S1 is connected to the output end of the first amplification branch AmpA.

[0169] The antenna port ANTB of the second switch S2 is connected to the isolation port 3 of the second circulator CircB, the receive port RX2 of the second switch S2 is connected to the corresponding receive channel RXB, and the transmit port TX2 of the second switch S2 is connected to the second amplification branch AmpB.

[0170] It should be noted that the antenna ports of S1 and S2 may alternatively be referred to as static contacts or non-moving ends from another perspective, and the receive and transmit ports of S1 and S2 may alternatively be referred to as moving contacts or moving ends from another perspective.

[0171] In the receive mode, the antenna port ANTA of S1 is connected to the receive port RX1, the antenna port ANTB of S2 is connected to the receive port RX2, the isolation port 3 of the first circulator CircA is connected to the corresponding receive channel RXA, and the isolation port 3 of the second circulator CircB is connected to the corresponding receive channel RXB.

[0172] 23 is explained by using an example in which the isolated port of the circulator is connected to the amplifier branch. The isolated port of the circulator may also be connected to an inter-frequency power dividing circuit. Referring to FIG. 24, the corresponding TDD mode implementation in which the isolated port is connected to an inter-frequency power dividing circuit will be described below.

[0173] FIG. 24 illustrates yet another radio frequency power amplifier according to an embodiment of the present application.

[0174] In FIG. 24, a first switch S1 and a second switch S2 are added based on FIG.

[0175] The antenna port ANTA of the first switch S1 is connected to the isolation port 3 of the first circulator CircA, the receiving port RX1 of the first switch S1 is connected to the corresponding receiving channel RXA, and the transmitting port TX1 of the first switch S1 is connected to the first output end of the first inter-frequency power dividing circuit Dipl.

[0176] The antenna port ANTB of the second switch S2 is connected to the isolation port 3 of the second circulator CircB, the receiving port RX2 of the second switch S2 is connected to the corresponding receiving channel RXB, and the transmitting port TX2 of the second switch S2 is connected to the second output end of the first inter-frequency power dividing circuit Dip1.

[0177] In the receive mode, the antenna port ANTA of S1 is connected to the receive port RX1, the antenna port ANTB of S2 is connected to the receive port RX2, the isolation port 3 of the first circulator CircA is connected to the corresponding receive channel RXA, and the isolation port 3 of the second circulator CircB is connected to the corresponding receive channel RXB.

[0178] Based on the radio frequency power amplifier provided in the above-mentioned embodiment, an embodiment of the present application further provides a remote radio unit. For details, please refer to Fig. 1. Fig. 1 is a diagram showing a remote radio unit according to an embodiment of the present application.

[0179] The remote radio unit provided in this embodiment includes the radio frequency power amplifier described in the above embodiments, and further includes a duplexer 100 .

[0180] One end of the radio frequency power amplifier is connected to the duplexer 100. Specifically, the duplexer 100 is connected between the antenna feed system and the radio frequency power amplifier, and the duplexer 100 is connected between the antenna feed system and the low noise amplifier.

[0181] The RRU 1000 includes a radio frequency power amplifier, a low noise amplifier (LNA), a duplexer 100, a transmit signal processing unit TX, a receive signal processing unit RX, and a common public radio interface (CPRI).

[0182] The remote radio unit provided in this embodiment of the present application includes the radio frequency power amplifier described in the above embodiment. The technical solution provided in this application converts a wideband problem into a narrowband problem. Some amplification branches in the radio frequency power amplifier are designed for narrowband to improve PA efficiency. Some amplification branches in the radio frequency power amplifier are designed for wideband to provide power sharing function. Furthermore, the narrowband circulator, together with the inter-frequency power division circuit, performs power synthesis on the signals output by the wideband amplification branches and the narrowband amplification branches, and outputs based on each frequency band. Narrowband isolators can be used at the lower level of each circulator, thereby eliminating the need for wideband isolators and reducing the design difficulty of the isolators.

[0183] Based on the radio frequency power amplifier and remote radio unit provided in the above-mentioned embodiments, the embodiments of the present application further provide a base station, which is described in detail below with reference to the accompanying drawings.

[0184] FIG. 25 is a diagram illustrating a base station according to one embodiment of the present application.

[0185] An embodiment of the present application further provides a base station 2000 including the remote radio unit 1000 described in the above embodiment and further including an antenna feeding system. The antenna feeding system may include multiple antennas. Two antennas, specifically, a first antenna ANT1 and a second antenna ANT2 configured to transmit or receive signals, are used as an example.

[0186] Furthermore, the base station 2000 may further include a baseband unit (BBU).

[0187] The base station provided in this embodiment of the present application includes the radio frequency power amplifier described in the above embodiment, so that the base station can perform ultra-wideband signal processing. Since signals of multiple frequency bands are output, the signals of each frequency band can be processed by an isolator for the corresponding frequency band. This reduces the design difficulty of the isolator, and an isolator with a narrow bandwidth can be used for implementation. Furthermore, the radio frequency power amplifier can achieve multiple high efficiency points, which reduces the size of the sub-region during backoff and is applicable to high-power scenarios, thereby enabling ultra-wideband high-power signal processing.

[0188] It should be understood that in this application, "at least one (item)" means one or more, and "more than one" means two or more. According to the technical essence of this application, any simple modifications, equivalent changes, and alterations made to the above-mentioned embodiments without departing from the content of the technical solution of this application shall fall within the protection scope of the technical solution of this application.

Claims

1. A radio frequency power amplifier comprising a first amplification branch, a second amplification branch, a third amplification branch, a first circulator, a second circulator, and a first inter-frequency power division circuit, The input terminal of the first amplification branch is configured to connect to the first signal path, the input terminal of the second amplification branch is configured to connect to the second signal path, and the input terminal of the third amplification branch is configured to connect to the third signal path. The output terminal of the third amplification branch is connected to the input terminal of the first interfrequency power divider circuit. The operating frequency band of the first amplification branch and the first circulator is frequency band A, the operating frequency band of the second amplification branch and the second circulator is frequency band B, the operating frequency band of the third amplification branch is frequency band A and frequency band B, and the first inter-frequency power division circuit is configured to output frequency band A signals and frequency band B signals. The output terminal of the first amplification branch and the first output terminal of the first inter-frequency power division circuit are connected to different ports of the first circulator, and the first circulator is configured to perform power summing on the frequency band A signal output by the first amplification branch and the frequency band A signal output by the first inter-frequency power division circuit, and then output the result. The output terminal of the second amplification branch and the second output terminal of the first inter-frequency power division circuit are connected to different ports of the second circulator, and the second circulator is configured to perform power summing on the frequency band B signal output by the second amplification branch and the frequency band B signal output by the first inter-frequency power division circuit, and then output the result. Radio frequency power amplifier.

2. The output terminal of the first amplification branch is connected to the isolation port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the input port of the first circulator. The output terminal of the second amplification branch is connected to the isolation port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the input port of the second circulator. The radio frequency power amplifier according to claim 1.

3. The output terminal of the first amplification branch is connected to the input port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the isolation port of the first circulator. The output terminal of the second amplification branch is connected to the input port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the isolation port of the second circulator. The radio frequency power amplifier according to claim 1.

4. The output terminal of the first amplification branch is connected to the input port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the isolation port of the first circulator. The output terminal of the second amplification branch is connected to the isolation port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the input port of the second circulator. The radio frequency power amplifier according to claim 1.

5. The output terminal of the first amplification branch is connected to the isolation port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the input port of the first circulator. The output terminal of the second amplification branch is connected to the input port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the isolation port of the second circulator. The radio frequency power amplifier according to claim 1.

6. The first amplification branch, the second amplification branch, and the third amplification branch are, respectively, Single-transistor power amplifier, Doherty power amplifier, Chireix power amplifier, switching-adjusted Doherty power amplifier, load-modulated balance amplifier (LMBA), or circulator load-modulated amplifier (CLMA) A radio frequency power amplifier according to any one of claims 1 to 5, wherein the power amplifier is any one of the following:

7. The first amplification branch, the second amplification branch, and the third amplification branch each include a single-transistor power amplifier, The single-transistor power amplifier included in the first amplification branch is a first carrier power amplifier, The single-transistor power amplifier included in the second amplification branch is a second carrier power amplifier, The single-transistor power amplifier included in the third amplification branch is a Peak power amplifier. The radio frequency power amplifier according to claim 6.

8. The radio frequency power amplifier according to claim 6, wherein the first amplification branch and the second amplification branch each include the Doherty power amplifier, and the third amplification branch comprises the single-transistor power amplifier, the single-transistor power amplifier included in the third amplification branch is a Peak power amplifier.

9. The radio frequency power amplifier according to claim 6, wherein the first amplification branch, the second amplification branch, and the third amplification branch each include the Doherty power amplifier.

10. Further comprising a second inter-frequency power division circuit, power distributor, and phase compensation network, A radio frequency power amplifier according to any one of claims 1 to 5, wherein the first output terminal of the power distributor is connected to the input terminal of the second interfrequency power division circuit, the first and second output terminals of the second interfrequency power division circuit are connected to the first amplification branch and the second amplification branch, respectively, the second output terminal of the power distributor is connected to the first terminal of the phase compensation network, and the second terminal of the phase compensation network is connected to the third amplification branch.

11. It further includes a third inter-frequency power division circuit, The output terminals of the first circulator and the second circulator are connected to the first and second input terminals of the third inter-frequency power divider circuit, respectively. The third inter-frequency power division circuit outputs the signal obtained through power synthesis. A radio frequency power amplifier according to any one of claims 1 to 5.

12. Further comprising a first switch and a second switch, The antenna port of the first switch is connected to the isolation port of the first circulator, the receiving port of the first switch is connected to the corresponding receiving channel, and the transmitting port of the first switch is connected to the output terminal of the first amplification branch. The antenna port of the second switch is connected to the isolation port of the second circulator, the receiving port of the second switch is connected to the corresponding receiving channel, and the transmitting port of the second switch is connected to the second amplification branch. A radio frequency power amplifier according to any one of claims 1 to 5.

13. Further comprising a first switch and a second switch, The antenna port of the first switch is connected to the isolation port of the first circulator, the receiving port of the first switch is connected to the corresponding receiving channel, and the transmitting port of the first switch is connected to the first output terminal of the first inter-frequency power division circuit. The antenna port of the second switch is connected to the isolation port of the second circulator, the receiving port of the second switch is connected to the corresponding receiving channel, and the transmitting port of the second switch is connected to the second output terminal of the first inter-frequency power division circuit. A radio frequency power amplifier according to any one of claims 1 to 5.

14. A remote wireless unit comprising a radio frequency power amplifier and a duplexer, wherein one end of the radio frequency power amplifier is connected to the duplexer, The radio frequency power amplifier includes a first amplification branch, a second amplification branch, a third amplification branch, a first circulator, a second circulator, and a first inter-frequency power division circuit. The input terminal of the first amplification branch is configured to connect to the first signal path, the input terminal of the second amplification branch is configured to connect to the second signal path, and the input terminal of the third amplification branch is configured to connect to the third signal path. The output terminal of the third amplification branch is connected to the input terminal of the first interfrequency power divider circuit. The operating frequency band of the first amplification branch and the first circulator is frequency band A, the operating frequency band of the second amplification branch and the second circulator is frequency band B, the operating frequency band of the third amplification branch is frequency band A and frequency band B, and the first inter-frequency power division circuit is configured to output frequency band A signals and frequency band B signals. The output terminal of the first amplification branch and the first output terminal of the first inter-frequency power division circuit are connected to different ports of the first circulator, and the first circulator is configured to perform power summing on the frequency band A signal output by the first amplification branch and the frequency band A signal output by the first inter-frequency power division circuit, and then output the result. The output terminal of the second amplification branch and the second output terminal of the first inter-frequency power division circuit are connected to different ports of the second circulator, and the second circulator is configured to perform power summing on the frequency band B signal output by the second amplification branch and the frequency band B signal output by the first inter-frequency power division circuit, and then output the result. Remote wireless unit.

15. The output terminal of the first amplification branch is connected to the isolation port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the input port of the first circulator. The output terminal of the second amplification branch is connected to the isolation port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the input port of the second circulator. The remote wireless unit according to claim 14.

16. The output terminal of the first amplification branch is connected to the input port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the isolation port of the first circulator. The output terminal of the second amplification branch is connected to the input port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the isolation port of the second circulator. The remote wireless unit according to claim 14.

17. The output terminal of the first amplification branch is connected to the input port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the isolation port of the first circulator. The output terminal of the second amplification branch is connected to the isolation port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the input port of the second circulator. The remote wireless unit according to claim 14.

18. The output terminal of the first amplification branch is connected to the isolation port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the input port of the first circulator. The output terminal of the second amplification branch is connected to the input port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the input port of the second circulator. The remote wireless unit according to claim 14.

19. A base station comprising a remote wireless unit and an antenna, The remote wireless unit is connected to the antenna, The remote wireless unit is configured to process the received and transmitted signals of the antenna. The remote wireless unit includes a radio frequency power amplifier and a duplexer, one end of the radio frequency power amplifier is connected to the duplexer, The radio frequency power amplifier includes a first amplification branch, a second amplification branch, a third amplification branch, a first circulator, a second circulator, and a first inter-frequency power division circuit. The input terminal of the first amplification branch is configured to connect to the first signal path, the input terminal of the second amplification branch is configured to connect to the second signal path, and the input terminal of the third amplification branch is configured to connect to the third signal path. The output terminal of the third amplification branch is connected to the input terminal of the first interfrequency power divider circuit. The operating frequency band of the first amplification branch and the first circulator is frequency band A, the operating frequency band of the second amplification branch and the second circulator is frequency band B, the operating frequency band of the third amplification branch is frequency band A and frequency band B, and the first inter-frequency power division circuit is configured to output frequency band A signals and frequency band B signals. The output terminal of the first amplification branch and the first output terminal of the first inter-frequency power division circuit are connected to different ports of the first circulator, and the first circulator is configured to perform power summing on the frequency band A signal output by the first amplification branch and the frequency band A signal output by the first inter-frequency power division circuit, and then output the result. The output terminal of the second amplification branch and the second output terminal of the first inter-frequency power division circuit are connected to different ports of the second circulator, and the second circulator is configured to perform power summing on the frequency band B signal output by the second amplification branch and the frequency band B signal output by the first inter-frequency power division circuit, and then output the result. Base station.

20. The output terminal of the first amplification branch is connected to the isolation port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the input port of the first circulator. The output terminal of the second amplification branch is connected to the isolation port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the input port of the second circulator. The base station according to claim 19.

21. The output terminal of the first amplification branch is connected to the input port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the isolation port of the first circulator. The output terminal of the second amplification branch is connected to the input port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the isolation port of the second circulator. The base station according to claim 19.

22. The output terminal of the first amplification branch is connected to the input port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the isolation port of the first circulator. The output terminal of the second amplification branch is connected to the isolation port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the input port of the second circulator. The base station according to claim 19.

23. The output terminal of the first amplification branch is connected to the isolation port of the first circulator, and the first output terminal of the first interfrequency power division circuit is connected to the input port of the first circulator. The output terminal of the second amplification branch is connected to the input port of the second circulator, and the second output terminal of the first interfrequency power division circuit is connected to the isolation port of the second circulator. The base station according to claim 19.

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