Broadband amplifying circuit and base station

Abstract

The invention provides a broadband amplification circuit and a base station. The circuit comprises a first main amplifier, a second main amplifier, a first auxiliary amplifier, a second auxiliary amplifier, a third auxiliary amplifier and a first coupler, the output end of the first main amplifier and the output end of the first auxiliary amplifier form a combined circuit and are connected to the first input end of the first coupler; the output end of the second main amplifier and the output end of the second auxiliary amplifier form a combined circuit and are connected to the second input end of the first coupler; the output end of the third auxiliary amplifier is connected to the third input end of the first coupler. The input ends of the first main amplifier and the second main amplifier are connected with a first broadband radio frequency signal; and the input ends of the first auxiliary amplifier, the second auxiliary amplifier and the third auxiliary amplifier are connected with a second broadband radio frequency signal. According to the invention, load traction can be carried out on the first main amplifier and the second main amplifier, so that the rollback efficiency is improved, and the problem that turn-off impedance is introduced into the first auxiliary amplifier and the second auxiliary amplifier when load traction is realized is avoided.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a broadband amplifier circuit and a base station. Background Art

[0002] With the commercialization of the fifth-generation mobile communication technology (5G), the available spectrum of broadband signals is increasing. The use of broadband amplification circuits (also called broadband amplifiers) to achieve multi-band signal coverage of base stations is a future development trend.

[0003] At present, the communication field has high performance requirements for implementing broadband amplifier circuits. How to improve the efficiency of the amplifier in the broadband amplifier circuit is a technical problem to be solved by this application. Summary of the invention

[0004] The purpose of this application is to provide a broadband amplification circuit and a base station, which can actively perform load pulling on the amplifier of the radio frequency power amplifier, thereby improving its back-off efficiency.

[0005] In order to achieve the above purpose, the embodiment of the present application is implemented as follows:

[0006] In the first aspect, a broadband amplifier circuit is provided, including: a first main amplifier, a second main amplifier, a first auxiliary amplifier, a second auxiliary amplifier, a third auxiliary amplifier and a first coupler; the output end of the first main amplifier and the output end of the first auxiliary amplifier form a combined circuit and are connected to the first input end of the first coupler; the output end of the second main amplifier and the output end of the second auxiliary amplifier form a combined circuit and are connected to the second input end of the first coupler; the output end of the third auxiliary amplifier is connected to the third input end of the first coupler. The input ends of the first main amplifier and the second main amplifier are connected to a first broadband radio frequency signal; the input ends of the first auxiliary amplifier, the second auxiliary amplifier and the third auxiliary amplifier are connected to a second broadband radio frequency signal; the first broadband radio frequency signal and the second broadband radio frequency signal each independently control the amplitude and phase.

[0007] In a second aspect, a base station is provided, comprising: the broadband amplifier circuit described in the first aspect.

[0008] Based on the broadband amplification circuit of the present application, the first broadband RF signal transmitted by the base station is split and then subjected to broadband power amplification through the first main amplifier and the second main amplifier, and then combined and output through the first coupler to meet the communication needs of high-power scenarios. In addition, the second broadband RF signal transmitted by the base station is split and then load-pulled on the first main amplifier through the first auxiliary amplifier and the third auxiliary amplifier to improve the fallback efficiency of the first main amplifier, and the second main amplifier is load-pulled through the second auxiliary amplifier and the third auxiliary amplifier to improve the fallback efficiency of the second main amplifier. In addition, the signal isolation between the first main amplifier and the first auxiliary amplifier, and the signal isolation between the second main amplifier and the second auxiliary amplifier to form a combined circuit also avoids the turn-off impedance problem introduced by the first auxiliary amplifier and the second auxiliary amplifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0010] Figure 1 A first structural schematic diagram of a broadband amplifier circuit provided in an embodiment of the present application.

[0011] Figure 2 A second structural schematic diagram of the broadband amplifier circuit provided in an embodiment of the present application.

[0012] Figure 3 A third structural schematic diagram of the broadband amplifier circuit provided in an embodiment of the present application.

[0013] Figure 4 A schematic diagram of the structure of a base station provided in an embodiment of the present application. DETAILED DESCRIPTION

[0014] As mentioned earlier, with the commercialization of 5G, the available spectrum for broadband signals is increasing. Using broadband amplification circuits to achieve multi-band signal coverage of base stations is a future development trend.

[0015] The core component of the broadband amplifier circuit is the power amplifier (PA), hereinafter referred to as the amplifier. In order for the amplifier to meet the performance requirements in the communication field, it is necessary to improve its overall efficiency when the power is backed off, that is, the back-off efficiency.

[0016] Load-Pull Ratio (LPR) is a parameter for evaluating amplifier back-off efficiency. LPR is the ratio of the impedance value of the amplifier at saturation power and back-off power. Since the available LPR for high efficiency is limited, the best amplifier architecture should be one that achieves high efficiency back-off with a smaller LPR. In addition, a smaller LPR is also beneficial to the RF bandwidth and can realize a broadband matching network.

[0017] In view of this, the present application aims to propose a broadband high-efficiency power amplifier solution that can actively reduce the amplifier LPR.

[0018] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this specification.

[0019] On the one hand, if Figure 1 As shown, an embodiment of the present application provides a broadband amplifier circuit, comprising: a first main amplifier Main1, a second main amplifier Main2, a first auxiliary amplifier Peak1, a second auxiliary amplifier Peak2, a third auxiliary amplifier Peak3 and a first coupler QHBC1. The output end of the first main amplifier Main1 and the output end of the first auxiliary amplifier Peak1 form a combined circuit and are connected to the first input end of the first coupler QHBC1; the output end of the second main amplifier Main2 and the output end of the second auxiliary amplifier Peak2 form a combined circuit and are connected to the second input end of the first coupler QHBC1; the output end of the third auxiliary amplifier Peak3 is connected to the third input end of the first coupler QHBC1.

[0020] In this embodiment, the output signals of the first main amplifier Main1 and the second main amplifier Main2 for the first broadband RF signal Pin1 are combined and output through the first coupler QHBC1 to achieve broadband power amplification as the RF output POUT. In addition, the input ends of the first auxiliary amplifier Peak1, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 are connected to the second broadband RF signal Pin2. Under the second broadband RF signal Pin2, the first auxiliary amplifier Peak1 and the third auxiliary amplifier Peak3 can load-pull the first main amplifier Main1 to improve the back-off efficiency of the first main amplifier Main1, and at the same time, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 can load-pull the second main amplifier Main2 to improve the back-off efficiency of the second main amplifier Main2.

[0021] On the basis of the above, the signal isolation between the output ends of the first main amplifier Main1 and the first auxiliary amplifier Peak1 is formed, and the signal isolation between the output ends of the second main amplifier Main2 and the second auxiliary amplifier Peak2 is formed, which can avoid the turn-off impedance problem introduced by the first auxiliary amplifier Peak1 and the second auxiliary amplifier Peak2.

[0022] Based on the above structure, the broadband amplifier circuit of this embodiment is provided with a load modulation mode and a non-load modulation mode.

[0023] When the broadband amplifier circuit is in non-load modulation mode, the first main amplifier Main1 and the second main amplifier Main2 are turned on, and the first auxiliary amplifier Peak1, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 are turned off. At this time, the first broadband RF signal Pin1 is power amplified by the first main amplifier Main1 and the second main amplifier Main2, and then combined and output by the first coupler QHBC1.

[0024] When the broadband amplifier circuit is in load modulation mode, the first main amplifier Main1, the second main amplifier Main2, the first auxiliary amplifier Peak1, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 are turned on at the same time. On the one hand, the first broadband RF signal Pin1 is power-amplified by the first main amplifier Main1 and the second main amplifier Main2, and then output by the first coupler QHBC1; on the other hand, the second broadband RF signal Pin2 is load-pulled to the first main amplifier Main1 under the power amplification of the third auxiliary amplifier Peak3 and the first auxiliary amplifier Peak1, and the second broadband RF signal Pin2 is load-pulled to the second main amplifier Main2 under the power amplification of the third auxiliary amplifier Peak3 and the second auxiliary amplifier Peak2.

[0025] It should be understood that the first broadband RF signal Pin1 and the second broadband RF signal Pin2 are communication signals transmitted by the base station. In this embodiment, the second broadband RF signal Pin2 is used to control the first auxiliary amplifier Peak1, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 to turn on or off, thereby switching between the load modulation mode and the non-load modulation mode.

[0026] That is, when the output power of the first main amplifier Main1 and / or the second main amplifier Main2 does not reach the back-off power, the amplitude of the second broadband radio frequency signal Pin2 is controlled to be at a relatively low level (for example, not less than a preset threshold), and the broadband amplifier circuit is in a non-load modulation mode. When the output power of the first main amplifier Main1 and / or the second main amplifier Main2 reaches the back-off power, the amplitude of the second broadband radio frequency signal Pin2 is controlled to be at a relatively high level (for example, greater than or equal to a preset threshold), and the broadband amplifier circuit is in a load modulation mode, and the load pulling of the first main amplifier Main1 and / or the second main amplifier Main2 is started, so that the impedance of the first main amplifier Main1 and / or the second main amplifier Main2 is pulled toward the saturation power point, and a relatively high efficiency is maintained.

[0027] The broadband amplifier circuit is introduced below with reference to specific examples.

[0028] In this embodiment, a circulator or a coupler may be used to implement signal isolation and combination between the first main amplifier Main1 and the first auxiliary amplifier Peak1 , and signal isolation and combination between the second main amplifier Main2 and the second auxiliary amplifier Peak2 .

[0029] for example Figure 2 As shown, the broadband amplifier circuit of this embodiment also includes: a first circulator Circulator1 and a second circulator Circulator2. The output ends of the first main amplifier Main1 and the first auxiliary amplifier Peak1 are connected to the input end of the first circulator Circulator1, the output end of the first circulator Circulator1 is connected to the first input end of the first coupler QHBC1, and the first main amplifier Main1 and the first auxiliary amplifier Peak1 are signal-isolated and combined through the first circulator Circulator1. At the same time, the output ends of the second main amplifier Main2 and the second auxiliary amplifier Peak2 are connected to the input end of the second circulator Circulator2, the output end of the second circulator Circulator2 is connected to the second input end of the first coupler QHBC1, and the second main amplifier Main2 and the second auxiliary amplifier Peak2 are signal-isolated and combined through the second circulator Circulator2. Figure 2In the structure shown, the first auxiliary amplifier Peak1 load-pulls the first main amplifier Main1 through the first circulator Circulator1, and the third auxiliary amplifier Peak3 load-pulls the first main amplifier Main1 through the first coupler QHBC1; at the same time, the second auxiliary amplifier Peak2 load-pulls the second main amplifier Main2 through the second circulator Circulator2, and the third auxiliary amplifier Peak3 load-pulls the second main amplifier Main2 through the first coupler QHBC1.

[0030] For example Figure 3 As shown, the number of the first main amplifier Main1 and the second main amplifier Main2 of this embodiment can be no less than two (taking two first main amplifiers Main1 and two second main amplifiers Main2 as an example), and the broadband amplifier circuit also includes: a second coupler QHBC2 and a third coupler QHBC3. Among them, the output ends of the first main amplifier Main1 and the first auxiliary amplifier Peak1 are connected to the input end of the second coupler QHBC2, the output end of the second coupler QHBC2 is connected to the first input end of the first coupler QHBC1, and the first main amplifier Main1 and the first auxiliary amplifier Peak1 are signal isolated and combined through the second coupler QHBC2. At the same time, the output ends of the second main amplifier Main2 and the second auxiliary amplifier Peak2 are connected to the input end of the third coupler QHBC3, the output end of the third coupler QHBC3 is connected to the second input end of the first coupler QHBC1, and the second main amplifier Main2 and the second auxiliary amplifier Peak2 are signal isolated and combined through the third coupler QHBC3. Figure 3 In the structure shown, the first auxiliary amplifier Peak1 load-pulls the first main amplifier Main1 through the second coupler QHBC2, and the third auxiliary amplifier Peak3 load-pulls the first main amplifier Main1 through the first coupler QHBC1; at the same time, the second auxiliary amplifier Peak2 load-pulls the second main amplifier Main2 through the third coupler QHBC3, and the third auxiliary amplifier Peak3 load-pulls the second main amplifier Main2 through the first coupler QHBC1.

[0031] Continue to use Figure 3For example, when the number of the first main amplifier Main1 and the second main amplifier Main2 of this embodiment is greater than one, the broadband amplifier circuit further includes: a fourth coupler QHBC4 and a fifth coupler QHBC5. Among them, the input end of the fourth coupler QHBC4 is connected to the first broadband RF signal Pin1, and the output end of the fourth coupler QHBC4 corresponds to each first main amplifier Main1 one by one, and is connected to the corresponding first main amplifier Main1; correspondingly, the first broadband RF signal Pin1 is fed to each first main amplifier Main1 through the fourth coupler QHBC4 branch. Similarly, the input end of the fifth coupler QHBC5 is connected to the first broadband RF signal Pin1, and the output end of the fifth coupler QHBC5 corresponds to each second main amplifier Main2 one by one, and is connected to the corresponding second main amplifier Main2; correspondingly, the first broadband RF signal Pin1 is fed to each second main amplifier Main2 through the fifth coupler QHBC5 branch.

[0032] In addition, reference Figure 2 and Figure 3 As shown, the broadband amplifier circuit further includes: a sixth coupler QHBC6 and a seventh coupler QHBC7. The input end of the sixth coupler QHBC6 is connected to the second broadband RF signal Pin2, the first output end of the sixth coupler QHBC6 is connected to the input end of the third auxiliary amplifier, the second output end of the sixth coupler QHBC6 is connected to the input end of the seventh coupler QHBC7, the first output end of the seventh coupler QHBC7 is connected to the input end of the first auxiliary amplifier Peak1, and the second output end of the seventh coupler QHBC7 is connected to the input end of the second auxiliary amplifier Peak2. That is, the second broadband RF signal Pin2 is fed to the third auxiliary amplifier and the seventh coupler QHBC7 through the sixth coupler QHBC6, and then fed to the first auxiliary amplifier Peak1 and the second auxiliary amplifier Peak2 through the seventh coupler QHBC7.

[0033] In addition, reference Figure 2 and Figure 3 As shown, the broadband amplifier circuit further includes: an eighth coupler QHBC8. The input end of the eighth coupler QHBC8 is connected to the first broadband radio frequency signal Pin1.

[0034] against Figure 2In the broadband amplifier circuit shown, when the first main amplifier Main1 and the second main amplifier Main2 are one, the first output end of the eighth coupler QHBC8 is connected to the input end of the first main amplifier Main1, and the second output end of the eighth coupler QHBC8 is connected to the input end of the second main amplifier Main2, that is, the first broadband RF signal Pin1 is fed to the first main amplifier Main1 and the second main amplifier Main2 through the eighth coupler QHBC8.

[0035] against Figure 3 In the broadband amplifier circuit shown, when the number of the first main amplifier Main1 and the second main amplifier Main2 is greater than one, the broadband amplifier circuit is equipped with a fourth coupler QHBC4 and a fifth coupler QHBC5. In this case, the first output end of the eighth coupler QHBC8 is connected to the input end of the fourth coupler QHBC4, and the second output end of the eighth coupler QHBC8 is connected to the input end of the fifth coupler QHBC5. That is, the first broadband RF signal Pin1 is fed to the fourth coupler QHBC4 and the fifth coupler QHBC5 through the eighth coupler QHBC8, and then fed to each first main amplifier Main1 through the fourth coupler QHBC4, and fed to each second main amplifier Main2 through the fifth coupler QHBC5.

[0036] In practical applications, all couplers of this embodiment may be orthogonal hybrid bridge couplers, and all auxiliary amplifiers may be peak amplifiers. The first RF signal Pin1 and the second RF signal Pin2 may be independently controlled in phase and amplitude.

[0037] by Figure 2Taking the broadband amplifier circuit shown as an example, the working principle is as follows: by setting different gate voltages for the main amplifier and the auxiliary amplifier, when the first broadband RF signal Pin1 is at a small amplitude, the first main amplifier Main1 and the second main amplifier Main2 are turned on first. As the amplitude of the input first broadband RF signal Pin1 increases, when the output power of the first main amplifier Main1 and the second main amplifier Main2 reaches the critical point of the back-off power, the first auxiliary amplifier Peak1, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 are turned on again. At this time, the first auxiliary amplifier Peak1 and the third auxiliary amplifier Peak3 provide peak power and form active load traction for the first main amplifier Main1. The load traction of the first auxiliary amplifier Peak1 and the load traction of the third auxiliary amplifier Peak3 offset each other to reduce or eliminate the LPR of the first main amplifier Main1, ensuring that the first main amplifier Main1 continues to work in a high-efficiency state. At the same time, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 simultaneously form load traction for the second main amplifier Main2, ensuring that the second main amplifier Main2 continues to work in a high-efficiency state. That is, a combination of the first main amplifier Main1 and the first auxiliary amplifier Peak1 and a combination of the second main amplifier Main2 and the second auxiliary amplifier Peak2 form a balanced power amplifier working mode, and are finally combined and outputted through the first coupler QHBC1.

[0038] by Figure 3Taking the broadband amplifier circuit shown in the figure as an example, the working principle is as follows: by setting different gate voltages for the main amplifier and the auxiliary amplifier, when the first broadband RF signal Pin1 is at a small amplitude, all the first main amplifiers Main1 and all the second main amplifiers Main2 are turned on first. As the amplitude of the input first broadband RF signal Pin1 increases, when the output power of all the first main amplifiers Main1 and all the second main amplifiers Main2 reaches the critical point of the back-off power, the first auxiliary amplifier Peak1, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 are turned on. At this time, the first auxiliary amplifier Peak1 and the third auxiliary amplifier Peak3 provide peak power, and form active load traction for each first main amplifier Main1. The load traction of the first auxiliary amplifier Peak1 and the load traction of the third auxiliary amplifier Peak3 offset each other to reduce or eliminate the LPR of the first main amplifier Main1; at the same time, the second auxiliary amplifier Peak2 and the third auxiliary amplifier Peak3 simultaneously form active load traction for each second main amplifier Main2, ensuring that each second main amplifier Main2 continues to work in a high-efficiency state. That is, a combination of the first main amplifier Main1 and the first auxiliary amplifier Peak1 and a combination of the second main amplifier Main2 and the second auxiliary amplifier Peak2 form a balanced power amplifier working mode, and are finally combined and outputted through the first coupler QHBC1.

[0039] On the other hand, Figure 4 As shown, another embodiment of the present application further provides a base station, including a broadband signal transmitter 400. The broadband signal transmitter 400 further includes the above Figures 1 to 3 The broadband amplifier circuit 410 shown in any one of the above.

[0040] It should be understood that based on the above-mentioned broadband amplification circuit 410, the first broadband RF signal transmitted by the broadband signal transmitter 400 is split and then subjected to broadband power amplification through the first main amplifier and the second main amplifier, and then combined and output through the first coupler to meet the communication requirements of high-power scenarios. In addition, the second broadband RF signal transmitted by the broadband signal transmitter 400 is split and then subjected to load pulling of the first main amplifier through the first auxiliary amplifier and the third auxiliary amplifier to improve the back-off efficiency of the first main amplifier, and the second main amplifier is subjected to load pulling of the second auxiliary amplifier and the third auxiliary amplifier to improve the back-off efficiency of the second main amplifier.

[0041] The above are only embodiments of this specification and are not intended to limit this specification. For those skilled in the art, this specification may be subject to various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this specification shall be included in the scope of the claims of this specification. In addition, all other embodiments obtained by ordinary technicians in this field without creative work shall fall within the scope of protection of this document.

Claims

1. A broadband amplifier circuit, characterized in that: include: a first main amplifier, a second main amplifier, a first auxiliary amplifier, a second auxiliary amplifier, a third auxiliary amplifier, and a first coupler; The output end of the first main amplifier and the output end of the first auxiliary amplifier form a combined circuit and are connected to the first input end of the first coupler; the output end of the second main amplifier and the output end of the second auxiliary amplifier form a combined circuit and are connected to the second input end of the first coupler; the output end of the third auxiliary amplifier is connected to the third input end of the first coupler; Among them, the input ends of the first main amplifier and the second main amplifier are connected to the first broadband RF signal; the input ends of the first auxiliary amplifier, the second auxiliary amplifier and the third auxiliary amplifier are connected to the second broadband RF signal; the first broadband RF signal and the second broadband RF signal each independently control the amplitude and phase.

2. The broadband amplifier circuit according to claim 1, characterized in that: Also includes: a first circulator and a second circulator; The output ends of the first main amplifier and the first auxiliary amplifier are connected to the input end of the first circulator, the output end of the first circulator is connected to the first input end of the first coupler, the first auxiliary amplifier performs load pulling on the first main amplifier through the first circulator, and the third auxiliary amplifier performs load pulling on the first main amplifier through the first coupler; The output ends of the second main amplifier and the second auxiliary amplifier are connected to the input end of the second circulator, the output end of the second circulator is connected to the second input end of the first coupler, the second auxiliary amplifier load-pulls the second main amplifier through the second circulator, and the third auxiliary amplifier load-pulls the second main amplifier through the first coupler.

3. The broadband amplifier circuit according to claim 1, characterized in that: Also includes: a second coupler and a third coupler; The output ends of the first main amplifier and the first auxiliary amplifier are connected to the input end of the second coupler, the output end of the second coupler is connected to the first input end of the first coupler, the first auxiliary amplifier performs load pulling on the first main amplifier through the second coupler, and the third auxiliary amplifier performs load pulling on the first main amplifier through the first coupler; The output ends of the second main amplifier and the second auxiliary amplifier are connected to the input end of the third coupler, the output end of the third coupler is connected to the second input end of the first coupler, the second auxiliary amplifier load-pulls the second main amplifier through the third coupler, and the third auxiliary amplifier load-pulls the second main amplifier through the first coupler.

4. The broadband amplifier circuit according to claim 1, characterized in that: The first main amplifiers are at least two, and the broadband amplification circuit further comprises: a fourth coupler; The input end of the fourth coupler is connected to the first broadband radio frequency signal, and the output end of the fourth coupler corresponds to each of the first main amplifiers one by one and is connected to the corresponding first main amplifier.

5. The broadband amplifier circuit according to claim 1, characterized in that: The second main amplifiers are no less than two, and the broadband amplification circuit further comprises: a fifth coupler; The input end of the fifth coupler is connected to the first broadband radio frequency signal, and the output end of the fifth coupler corresponds to each of the second main amplifiers one by one and is connected to the corresponding second main amplifier.

6. The broadband amplifier circuit according to any one of claims 1 to 5, characterized in that: Also includes: a sixth coupler and a seventh coupler; Among them, the input end of the sixth coupler is connected to the second broadband RF signal, the first output end of the sixth coupler is connected to the input end of the third auxiliary amplifier, the second output end of the sixth coupler is connected to the input end of the seventh coupler, the first output end of the seventh coupler is connected to the input end of the first auxiliary amplifier, and the second output end of the seventh coupler is connected to the input end of the second auxiliary amplifier.

7. The broadband amplifier circuit according to any one of claims 1 to 5, characterized in that: When the broadband amplifier circuit is in a non-load modulation mode, the first main amplifier and the second main amplifier are turned on, and the first auxiliary amplifier, the second auxiliary amplifier and the third auxiliary amplifier are turned off; when the broadband amplifier circuit is in a load modulation mode, the first main amplifier, the second main amplifier, the first auxiliary amplifier, the second auxiliary amplifier and the third auxiliary amplifier are turned on.

8. The broadband amplifier circuit according to claim 7, characterized in that: The broadband amplification circuit is in a non-load modulation mode when the output power of the first main amplifier and / or the second main amplifier does not reach the back-off power, and is in the load modulation mode when the output power of the first main amplifier and / or the second main amplifier reaches the back-off power.

9. The broadband amplifier circuit according to any one of claims 1 to 5, characterized in that: The first coupler is an orthogonal hybrid bridge coupler; the first auxiliary amplifier, the second auxiliary amplifier and the third auxiliary amplifier are peak amplifiers.

10. A base station, comprising a broadband signal transmitter, characterized in that: The broadband signal transmitter comprises the broadband amplification circuit as described in any one of claims 1-9.

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