Power amplifier device, remote radio unit and base station

Abstract

The invention discloses a power amplifier device, a remote radio unit and a base station, the power amplifier device can be applied to input of three paths of signals at most, power synthesis is carried out by adopting a hybrid cascade mode of a coupler and a circulator, the coupler can be used as the last-stage power synthesis unit, and the circulator can also be used as the last-stage power synthesis unit. The power amplifier device can generate at least three high-efficiency points, and due to the fact that the number of the high-efficiency points is large, the problem of efficiency pits during large rollback can be solved, and the modulation wave efficiency of the radio frequency power amplifier device is improved. And the working bandwidth of the power amplifier device depends on the working bandwidths of the first power amplifier circuit, the coupler and the circulator, so that the design of ultra wide band and high power can be realized.

Description

Power amplifier device, radio frequency remote unit and base station Technical Field

[0001] The present application relates to the technical field of communication equipment, and in particular to a power amplifier device, a radio remote unit and a base station. Background Art

[0002] Currently, wireless communication systems require wide bandwidth and high spectral efficiency. For example, the 5G NR (5G New Radio) standard defines the N77 frequency band from 3.3 GHz to 4.2 GHz, or 900 MHz of bandwidth, for concurrent broadband signals. Furthermore, even with the use of crest factor reduction (CFR) peak-to-average power ratio (P / A) in the 5G NR high-efficiency spectrum signal waveform, the peak-to-average power ratio (PAPR) remains as high as 9 dB. This high peak-to-average power ratio (PAPR) and wide instantaneous bandwidth pose new challenges to the base station's power amplifier (PA).

[0003] Therefore, with the development of wireless communication systems, the power amplifier of the base station needs to achieve ultra-wideband characteristics while meeting high efficiency.

[0004] Summary of the Invention

[0005] In order to solve the above technical problems, the present application provides a power amplifier device, a radio remote unit and a base station, which can achieve ultra-wideband characteristics while meeting high efficiency.

[0006] The present application provides a power amplifier device, which includes, in addition to the following three power amplifier circuits: a first power amplifier circuit, a second power amplifier circuit, and a third power amplifier circuit, a first coupler and a circulator; wherein the circulator serves as the last-stage power synthesis unit; wherein the input ends of the first power amplifier circuit, the second power amplifier circuit, and the third power amplifier circuit respectively input the first signal, the second signal, and the third signal, the output end of the first power amplifier circuit and the output end of the second power amplifier circuit are both connected to the input end of the first coupler, and the first coupler outputs the power-synthesized signal; the output end of the first coupler and the output end of the third power amplifier circuit are connected to the circulator, and the circulator synthesizes the power of the signal output by the third power amplifier circuit with the signal output by the coupler and outputs the resultant signal.

[0007] The power amplifier device provided in this application is suitable for the input of up to three signals, and adopts a mixed cascade method of a coupler and a circulator for power synthesis. The coupler can be used as the last-stage power synthesis unit, or the circulator can be used as the last-stage power synthesis unit. The power amplifier device can generate at least three high-efficiency points. Since there are many high-efficiency points, the efficiency pit problem during large back-off can be improved, and the modulation wave efficiency of the RF power amplifier device can be improved. Moreover, the operating bandwidth of the power amplifier device depends on the operating bandwidth of the first power amplifier circuit, the coupler, and the circulator, and an ultra-wideband and high-power design can be achieved. Moreover, the last-stage power synthesis unit of the power amplifier is realized by a circulator, which is more suitable for use in scenarios with larger power capacity. Therefore, the power amplifier is suitable for high-power ultra-wideband scenarios.

[0008] The present application also provides a power amplifier device, which includes, in addition to the following three power amplifier circuits: a first power amplifier circuit, a second power amplifier circuit, and a third power amplifier circuit, a first coupler and a circulator; wherein the coupler serves as the last-stage power synthesis unit; wherein the input ends of the first power amplifier circuit, the second power amplifier circuit, and the third power amplifier circuit respectively input the first signal, the second signal, and the third signal, and the output end of the first power amplifier circuit and the output end of the second power amplifier circuit are both connected to the circulator, and the circulator is used to output the power-synthesized signal; the output end of the circulator and the output end of the third power amplifier circuit are connected to the first coupler, and the first coupler is used to synthesize the power of the signal output by the third power amplifier circuit with the signal output by the circulator and output them.

[0009] The present application does not specifically limit the characteristic impedance of the circulator, which may be 50 ohms, for example.

[0010] The present application does not specifically limit the implementation form of the first power amplifier circuit. It can be a single-tube power amplifier or an integrated amplifier. For example, the first power amplifier circuit can include any one of the following: a single-tube power amplifier, a Doherty power amplifier, a Chireix power amplifier, a load modulated balanced amplifier (LMBA, Load Modulated Balanced Amplifier) ​​or a circulator load modulated amplifier (CLMA, Circulator Load Modulated Amplifier) ​​power amplifier.

[0011] The second power amplifier circuit includes a first amplifying branch and a second amplifying branch; the third power amplifier circuit includes a third amplifying branch; the first amplifying branch and the second amplifying branch are identical and are both biased in shallow Class C; the third amplifying branch is biased in deep Class C. For example, the first amplifying branch, the second amplifying branch, and the third amplifying branch can all be peak power amplifiers, referred to as Peak.

[0012] The following is an introduction to the first power amplifier circuit, which is a single-tube power amplifier. When the single-tube power amplifier is biased in Class AB or Class B, it is a carrier power amplifier, referred to as Main. The power amplifier device also includes: a second coupler and a matching circuit; the input end of the carrier power amplifier is used to input the first signal, and the output end of the carrier power amplifier is connected to the isolation port of the first coupler; the first input port of the second coupler is used to input the second signal, and the second input port of the second coupler is connected to a load; the first input port of the second coupler is used to connect the second signal, and the second input port of the second coupler is used to connect the load; the two output ends of the second coupler are respectively connected to the input end of the first amplifying branch and the input end of the second amplifying branch, and the output end of the first amplifying branch and the output end of the second amplifying branch are respectively connected to the two balanced ports of the first coupler; the output port of the first coupler is connected to the first end of the matching circuit, and the second end of the matching circuit is connected to the isolation port of the circulator; the input end of the third amplifying branch is used to input the third signal, the output end of the third amplifying branch is connected to the input port of the circulator, and the output port of the circulator is used to output a signal obtained by combining the signal powers of the isolation port and the input port.

[0013] The load-pull ratio of the first power amplifier circuit is 1, meaning that as the power of the power amplifier device changes, the load of the first power amplifier circuit remains unchanged. Therefore, the operating bandwidth of the power amplifier device depends only on the operating bandwidth of the single-tube power amplifier and the operating bandwidth of the coupler and circulator, and ultra-wideband can be achieved through design. Furthermore, the power amplifier has three high-efficiency points, which can improve the problem of large pits during power reduction. Furthermore, the final power synthesis unit of the power amplifier is implemented by a circulator, which is more suitable for applications with higher power capacity. Therefore, the power amplifier is suitable for high-power ultra-wideband scenarios.

[0014] To achieve miniaturization of the power amplifier, the coupler can be designed using integrated passive components. The circulator can be designed as a three-port circulator. Alternatively, the circulator can be combined with an isolator connected to the output stage to form a four-port circulator.

[0015] The power amplifier device provided in the present application can also input two signals. In addition to the devices included above, it also includes: a first power dividing circuit and a first phase compensation network; the first power dividing circuit is used to output the first signal and the second signal, and the end of the first power dividing circuit outputting the first signal is connected to the input end of the first phase compensation network, the output end of the first phase compensation network is connected to the input end of the carrier power amplifier, and the end of the first power dividing circuit outputting the second signal is connected to the first input port of the second coupler.

[0016] The power amplifier device provided in the present application can also input a signal. In addition to the devices included above, it also includes: a second power division circuit and a second phase compensation network; the two output ends of the second power division circuit are respectively connected to the input end of the first power division circuit and the input end of the second phase compensation network; the output end of the second phase compensation network is connected to the input end of the third amplification branch.

[0017] The first power amplifier circuit is a single-tube power amplifier, which is a carrier power amplifier when biased in class AB or class B; the second power amplifier circuit includes a fourth amplifying branch; the third power amplifier circuit includes a fifth amplifying branch and a sixth amplifying branch; the fourth amplifying branch is biased in shallow class C, and the fifth amplifying branch and the sixth amplifying branch are the same and are both biased in deep class C.

[0018] The following describes a specific implementation method when a circulator is used as the last-stage power combining unit. The power amplifier device also includes: a second coupler, a first matching circuit, and a second matching circuit; the input end of the first power amplifier circuit is used to input the first signal, and the output end of the first power amplifier circuit is connected to the isolated port of the circulator; the input end of the fourth amplifier branch is used to connect to the second signal, the output end of the fourth amplifier branch is connected to the input port of the circulator, the output port of the circulator is connected to the first end of the first matching circuit, and the second end of the first matching circuit is connected to the isolated port of the first coupler; the first input port of the second coupler is used to connect to the third signal, and the second input port of the second coupler is connected to a load; the first input port of the second coupler is used to connect to the third signal, and the second input port of the second coupler is used to connect to the load; the input end of the fifth amplifier branch and the input end of the sixth amplifier branch are respectively connected to the two output ends of the second coupler, and the output end of the fifth amplifier branch and the output end of the sixth amplifier branch are respectively connected to the two balanced ports of the first coupler; the output port of the first coupler is connected to the first end of the second matching circuit, and the output end of the second matching circuit is used to output the power-combined signal.

[0019] In the power amplifier device provided in the present application, the first power amplifier circuit works first, the second power amplifier circuit works later, and the third power amplifier circuit works last. The first power amplifier circuit reaches saturation first, then the second power amplifier circuit reaches protection, and finally the third power amplifier circuit reaches protection.

[0020] Based on the power amplifier device provided above, the present application also provides a radio frequency remote unit, including the power amplifier device introduced above, and also including: a duplexer; one end of the power amplifier device is connected to the duplexer, and the duplexer can both send and receive radio frequency signals.

[0021] Based on the radio remote unit provided above, the present application also provides a base station, including the radio remote unit introduced above, and also including: an antenna; the radio remote unit is connected to the antenna; the radio remote unit is used to process the transmit and receive signals of the antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG1 is a schematic diagram of a remote radio unit (RRU);

[0023] FIG2 is a schematic diagram of a power amplifier device provided in an embodiment of the present application;

[0024] FIG3 is a current diagram of a power amplifier device provided in an embodiment of the present application;

[0025] FIG4 is a voltage diagram of a power amplifier device provided in an embodiment of the present application;

[0026] FIG5 is an impedance diagram of a power amplifier device provided in an embodiment of the present application;

[0027] FIG6 is an efficiency curve corresponding to FIG2 provided in an embodiment of the present application;

[0028] FIG7 is a schematic diagram of a power amplifier corresponding to two signals provided in an embodiment of the present application;

[0029] FIG8 is a schematic diagram of a power amplifier corresponding to one signal provided in an embodiment of the present application;

[0030] FIG9 is a schematic diagram of an efficiency curve provided in an embodiment of the present application;

[0031] FIG10 is a schematic diagram of another power amplifier device provided in an embodiment of the present application;

[0032] FIG11 is a schematic diagram of the efficiency curve corresponding to FIG10;

[0033] FIG12 is a schematic diagram of another power amplifier device provided in an embodiment of the present application;

[0034] FIG13 is a schematic diagram of the efficiency curve corresponding to FIG12;

[0035] FIG14 is a schematic diagram of a base station provided in an embodiment of the present application. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0037] The terms "first," "second," and the like in the following description are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified with "first," "second," and the like may explicitly or implicitly include one or more of such features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0038] In this application, unless otherwise specified or limited, the term "connection" should be understood broadly. For example, "connection" can mean fixed connection, detachable connection, or integration; it can mean direct connection or indirect connection through an intermediate medium. In addition, the term "coupling" can refer to the method of electrical connection for signal transmission. "Coupling" can mean direct electrical connection or indirect electrical connection through an intermediate medium.

[0039] In order to achieve ultra-wideband, high-efficiency power amplification of the input signal, the present application provides a power amplifier device that is suitable for up to three signal inputs. It uses a hybrid cascade of a coupler and a circulator for power synthesis, which can produce three high-efficiency points and solve the problem of efficiency pits during large back-off. The efficiency pit refers to the trough on the efficiency curve when the power is backed off. This power amplifier device is suitable for use in high-power power amplifier scenarios.

[0040] In order to enable those skilled in the art to better understand the technical solution provided by the embodiments of the present application, the application scenarios of the technical solution are first introduced below with reference to the accompanying drawings.

[0041] The power amplifier device provided in the embodiments of the present application is introduced by taking a radio remote unit (RRU) used in a base station as an example.

[0042] An RRU typically includes many radio frequency modules, of which a power amplifier is a key component. Wireless signals are amplified by the power amplifier and then transmitted through the antenna. Because the power amplifier processes radio frequency signals, it is considered an RF power amplifier. The present application embodiment specifically relates to a power amplifier within an RRU. The power amplifier includes a power amplifier. For ease of description, the power amplifier will be referred to as a power amplifier below.

[0043] Refer to FIG1 , which is a schematic diagram of an RRU.

[0044] The RRU 1000 provided in the embodiment of the present application can be applied to a base station for wireless communication. In addition to the RRU 1000 , the base station may also include other components, for example, an antenna Ant, which will not be described in detail here.

[0045] The RRU 1000 includes a power amplifier device 200, a low noise amplifier (LNA) and a duplexer 100. The power amplifier device 200 includes a power amplifier PA.

[0046] The radio frequency signal amplified by the PA is sent to the antenna Ant through the duplexer 100.

[0047] The radio frequency signal received by the antenna Ant is sent to the LNA through the duplexer 100 .

[0048] The power amplifier device 200 provided in the embodiment of the present application can have a final power combining unit which can be a coupler or a circulator, which will be described in detail below with reference to the accompanying drawings.

[0049] The power amplifier device provided in this embodiment includes: a first power amplifier circuit, a second power amplifier circuit, a third power amplifier circuit, a coupler, and a circulator. A first signal and a second signal are respectively amplified by the first power amplifier circuit and the second power amplifier circuit, and then input into the coupler. The coupler combines the power of the first signal into a single output signal. The third signal is amplified by the third power amplifier circuit and then output. The circulator combines the power of the signal output by the third power amplifier circuit and the signal output by the coupler and outputs the combined signal.

[0050] Among them, the first power amplifier circuit works first, the second power amplifier circuit works later, and the third power amplifier circuit works last.

[0051] The first power amplifier circuit may be implemented in various forms, for example, it may include any one of the following: a single-tube power amplifier, a Doherty power amplifier, a Chireix power amplifier, an LMBA, or a CLMA.

[0052] When the first power discharging route is implemented using a single-tube amplifier, the single-tube amplifier is biased in Class AB or Class B and is called a carrier amplifier, also known as a main amplifier, denoted by "Main." The following describes the implementation of the first power discharging route using a single-tube amplifier.

[0053] See FIG2 , which is a schematic diagram of a power amplifier device provided in an embodiment of the present application.

[0054] The first power amplifier circuit is a single-tube power amplifier, called the carrier power amplifier Main, which is also called the main power amplifier.

[0055] The second power amplifier circuit includes a first amplifying branch and a second amplifying branch; the first amplifying branch and the second amplifying branch are identical and are both biased in shallow class C, so they are both represented by Peak1. It should be understood that the amplifying branch provided in the embodiment of the present application may include a peak power amplifier, which is also called an auxiliary power amplifier.

[0056] The third power amplifier circuit includes a third amplifying branch, which is biased in deep class C and is represented by Peak2.

[0057] As shown in FIG2 , the first signal Input1 is input to the input end of the carrier power amplifier Main, and the output end of the carrier power amplifier Main is connected to the isolation port of the first coupler Cou2;

[0058] The second signal Input2 is input to the first input port of the second coupler Cou1, and the second input port of the second coupler Cou1 is connected to the load. After power splitting by the second coupler Cou1, the second signal Input2 is respectively input to the input end of the first amplifying branch Peak1 and the input end of the second amplifying branch Peak1. The output end of the first amplifying branch Peak1 and the output end of the second amplifying branch Peak1 are respectively connected to the two balanced ports of the first coupler Cou2.

[0059] The output port of the first coupler Cou2 is connected to the isolated port 3 of the circulator Cir through the matching circuit MN;

[0060] The third signal Input3 is input to the input end of the third amplifying branch Peak2. The output end of the third amplifying branch Peak2 is connected to the input port 1 of the circulator Cir. The output port 2 of the circulator Cir is used to output the signal after the signal power of the circulator isolation port and the circulator input port is synthesized, that is, the Output outputs the final amplified signal.

[0061] The characteristic impedance of the first coupler Cou2 is Z01. The characteristic impedance of the circulator Cir is Z02. It should be noted that the characteristic impedance Z02 of the circulator is generally 50 ohms.

[0062] The matching resistor MN is used to achieve impedance conversion from Z01 to Z02, thereby achieving impedance matching between the first coupler Cou2 and the circulator Cir.

[0063] When the input signal power is low, since the Main circuit operates in Class AB or Class B, the Main circuit operates first, that is, only the Main circuit operates until the Main circuit reaches saturation. Then the two Peak1 circuits are turned on while Peak2 is still off. The Main circuit remains saturated until the two Peak1 circuits reach saturation. After Peak1 reaches saturation, Peak2 is turned on. The Main circuit and Peak1 remain saturated until the Main circuit, the two Peak1 circuits, and Peak2 reach saturation.

[0064] For example, when Main:Peak1:Peak1:Peak2=1:2:2:10, when the voltage is normalized, the current schematic diagram and voltage schematic diagram of Main, two Peak1s, and Peak2 are respectively shown in FIG3 and FIG4 .

[0065] The horizontal axes in FIG3 and FIG4 are both normalized voltage (V0 / Vdd), the vertical axis in FIG3 represents current (Current), and the vertical axis in FIG4 represents voltage (Voltage).

[0066] As can be seen from the current diagram in Figure 3, Main operates first, then Peak1, and finally Peak2. In Figure 3, Imain reaches current saturation earlier than Ipeak1, and Ipeak1 reaches current saturation earlier than Ipeak2.

[0067] As can be seen from the voltage diagram shown in FIG4 , Main is saturated first, then Peak1 is saturated, and finally Peak2 is saturated. That is, Vmain in FIG3 reaches voltage saturation earlier than Vpeak1, Vpeak1 reaches voltage saturation earlier than Vpeak2, and finally Vpeak2 reaches voltage saturation.

[0068] There is no load pull between Main and Peak1, nor between Main and Peak1 and Peak2; the load pull ratio of the Main circuit is 1. Therefore, the operating bandwidth of the power amplifier device shown in Figure 2 depends only on the operating bandwidth of the single-tube power amplifier and the operating bandwidth of the coupler and circulator.

[0069] FIG5 shows the voltage normalization when Main:Peak1:Peak1:Peak2=1:2:2:10, and a schematic diagram of the impedance relationship between Main, the two Peak1s, and Peak2.

[0070] The horizontal axis of FIG. 5 represents the normalized voltage (V0 / Vdd), and the vertical axis of FIG. 5 represents the impedance (Impedance).

[0071] As can be seen from Figure 5, the impedance Zmain of Main remains constant, that is, a straight line parallel to the horizontal axis, so the load-pull ratio of Main is equal to 1.

[0072] The power amplifier device provided in the embodiment of the present application can achieve three high efficiency points, which are described in detail below in conjunction with the efficiency curve.

[0073] See Figure 6, which is an efficiency curve corresponding to Figure 2 provided in an embodiment of the present application.

[0074] FIG6 continues to introduce the case of Main:Peak1:Peak1:Peak2=1:2:2:10 and voltage normalization. The abscissa of FIG6 is the normalized voltage (V0 / Vdd), and the ordinate of FIG6 represents efficiency (DE).

[0075] Main reaches saturation at the first high efficiency point. Peak1 reaches saturation at the second high efficiency point. At the third high efficiency point, Main, Peak1, and Peak2 all reach saturation. Therefore, the power amplifier provided in the embodiment of the present application can generate three high efficiency points.

[0076] The power amplifier device provided in the embodiment of the present application is in the LMBA working state between the first high efficiency point and the second high efficiency point, and is in the CLMA working state between the second high efficiency point and the third high efficiency point.

[0077] In the power amplifier device provided in this embodiment, since the load-pull ratio of the Main circuit is 1, the bandwidth of the power amplifier is related to the Main circuit, the coupler, and the circulator, enabling ultra-wideband design. Furthermore, the power amplifier device has three high-efficiency points, which can alleviate the problem of large dips during power backoff. Furthermore, the final power combining unit of the power amplifier device is implemented by a circulator, which is more suitable for use in scenarios with higher power capacity. Therefore, the power amplifier device is suitable for high-power ultra-wideband scenarios.

[0078] The characteristic impedance of the above coupler and circulator can be set according to actual needs. For example, when the impedance of the circulator is not 50 ohms, in order to achieve a 50 ohm effect, an impedance transformation network Z02 to 50 ohms can be added at the output end as needed.

[0079] In addition, in order to achieve miniaturization of the power amplifier, the coupler can be designed using an integrated passive device (IPD).

[0080] The circulator shown in Figure 2 is a three-port design.

[0081] The circulator can be designed as a four-port circulator in combination with an isolator connected to the output stage.

[0082] The power amplifier device introduced in FIG2 takes a three-channel signal input power amplifier as an example. It should be understood that the power amplifier device provided in the embodiment of the present application can also be applied to a one-channel signal input or a two-channel signal input scenario. A detailed introduction is given below in conjunction with the accompanying drawings.

[0083] See FIG. 7 , which is a schematic diagram of a power amplifier device corresponding to two signals provided in an embodiment of the present application.

[0084] The input terminal of the power amplifier device provided in this embodiment can be connected to two signals. Comparing FIG2 and FIG7 , it can be found that FIG7 includes, in addition to the components of FIG2 , a first power dividing circuit Sp1 and a first phase compensation network Comp1;

[0085] The first signal and the second signal in FIG2 can be regarded as two signals after power division by the first power divider circuit Sp1. The first signal is connected to the input end of the carrier power amplifier Main through the first phase compensation network Comp1.

[0086] The first phase compensation network Comp1 is used to achieve phase compensation.

[0087] It can be seen that in order to achieve power amplification of two input signals, the power amplifier device provided in the embodiment of the present application adds a first power dividing circuit Sp1 and a first phase compensation network Comp1 on the basis of FIG. 2 .

[0088] In addition, the power amplifier device provided in the embodiment of the present application can also be applied to the scenario of single-channel signal input. On the basis of Figure 7, a second power division circuit and a second phase compensation network are added to achieve power amplification of the single-channel input signal.

[0089] See FIG8 , which is a schematic diagram of a power amplifier device corresponding to one signal provided in an embodiment of the present application.

[0090] Comparing FIG7 and FIG8 , it can be found that the power amplifier device of FIG8 includes, in addition to the components of FIG7 , further including: a second power splitter circuit Sp2 and a second phase compensation network Comp2;

[0091] The third signal is connected to the input end of the third amplifying branch Peak2 through the second phase compensation network Comp2;

[0092] The third signal and the input signal of the first power dividing circuit Sp1 are two signals after power division by the second power dividing circuit Sp2.

[0093] In order to fully understand the high efficiency and back-off amount of the power amplifier device provided in the embodiments of the present application, a detailed introduction is given below with reference to the accompanying drawings.

[0094] See FIG9 , which is a schematic diagram of an efficiency curve provided in an embodiment of the present application.

[0095] FIG9 shows the efficiency Eff of the power amplifier device. In FIG9 , the horizontal axis represents the output power of the power amplifier device, and the vertical axis represents the efficiency DE.

[0096] For example, the three high efficiency points of the power amplifier device provided in this embodiment appear at the full power 0dB, the first power back-off point BO1, and the second power back-off point BO2. The calculations of BO1 and BO2 are shown below:

[0097]

[0098]

[0099] Among them, Psat main Indicates the saturation power of Main, Psat peak1 Indicates the saturation power of Peak1, Psat peak2 Indicates the saturation power of Peak2.

[0100] Assuming Main:Peak1:Peak1:Peak2 = 100w:200w:200w:1000w; then BO1 = 11.76; BO2 = 4.77dB; its efficiency curve is shown in Figure 9, with three high-efficiency points at 61.77dBm, 57dBm, and 50dBm, respectively. That is, the peak position of the curve is the high-efficiency point, and the power back-off amount can reach 11.76dB, that is, the power back-off amount is relatively large and the pit is relatively small.

[0101] The first power amplifier circuit in the power amplifier device described in the above embodiment is implemented by a single-tube power amplifier. The following describes a case where the first power amplifier circuit is implemented by a Doherty power amplifier. It should be understood that in addition to the Doherty power amplifier, the first power amplifier circuit can also be implemented by a Chireix power amplifier, an LMBA power amplifier, or a CLMA power amplifier.

[0102] See FIG. 10 , which is a schematic diagram of another power amplifier device provided in an embodiment of the present application.

[0103] Comparing FIG2 and FIG10 , it can be seen that the Main in FIG2 is replaced by a Doherty (DHT) amplifier, and the rest of the structure remains unchanged and will not be described in detail here.

[0104] The Doherty power amplifier includes: a second coupler Cou3, a carrier power amplifier Main and a peak power amplifier Peak, and also includes an impedance inversion network INT and a matching network DHT_MN.

[0105] The first signal Input1 is input to the first input port of the second coupler Cou3. The second input port of the second coupler Cou3 is connected to the load. After power splitting by the second coupler Cou3, the first signal is input to Main and Peak respectively. The signal output by Main is combined with the signal output by Peak after passing through INT, and then input to the isolation port 4 of the first coupler Cou2 through DHTMN.

[0106] In Figure 10, Main works first, then Peak works, then the two Peak1s work, and finally Peak2 works.

[0107] In this embodiment, the Doherty amplifier is used to replace the Main in Figure 2, which can realize the design of an ultra-large back-off amplifier architecture. Compared with Figure 2, the back-off amount increases the back-off amount of the DHT amplifier, that is, the back-off amount is further increased.

[0108] Compared with the power amplifier device shown in FIG2 , the power amplifier device shown in FIG10 can generate many high efficiency points. FIG2 can generate three high efficiency points, and FIG10 can generate four high efficiency points, thereby further preventing the problem of large pits during power fallback.

[0109] See FIG11 , which is a schematic diagram of the efficiency curve corresponding to FIG10 .

[0110] In FIG11 , the horizontal axis is the output power Pout in dB m, and the vertical axis is the efficiency DE.

[0111] For example, Main:Peak:Peak2:Peak2:Peak3=50w:50w:200w:200w:1000w, which generates four high efficiency points at 61.77dBm, 57dBm, 50dBm, and 44dBm respectively, achieving a back-off of 17.77dB.

[0112] The output power of 44dBm to 50dBm is DHT-pulled, the output power of 50dBm to 57dBm is LMBA-pulled, and the output power of 57dBm to 61.77dBm is CLMA-pulled.

[0113] It should be understood that the power amplifier circuit connected to the isolated port of the first coupler Cou2 can be independently set and can be a single-tube power amplifier; it can also be a DHT, and can also be an asymmetric DHT, a three-way DHT or a four-way DHT, a Chireix power amplifier, an LMBA power amplifier or a CLMA power amplifier, and the corresponding broadband characteristics are further determined by the broadband characteristics of the independently set power amplifier unit.

[0114] The final output signals of the power amplifier devices described in the above embodiments are all synthesized by the circulator. The circulator is more suitable as the final power synthesizer in high-power scenarios and can solve the power capacity problem of high-power broadband power amplifiers.

[0115] The following describes how the final output signal is synthesized by a coupler.

[0116] See Figure 12, which is a schematic diagram of another power amplifier device provided in an embodiment of the present application.

[0117] In the power amplifier device provided in the embodiment of the present application, a circulator first synthesizes two amplified signals, and then a coupler synthesizes the output signal of the circulator with a third amplified signal, and finally outputs a power synthesized signal.

[0118] In the power amplifier device provided in the embodiment of the present application, the first power amplifier circuit is a single-tube power amplifier, which is biased in class AB or class B and is called a carrier power amplifier, i.e., Main; the second power amplifier circuit includes a fourth amplifying branch; and the third power amplifier circuit includes a fifth amplifying branch and a sixth amplifying branch.

[0119] The fourth amplifying branch is biased in the shallow C class and is represented by Peak1. The fifth amplifying branch and the sixth amplifying branch are the same and are both biased in the deep C class, so they are both represented by Peak2.

[0120] The first signal Input1 is input to the input end of the first power amplifier circuit Main, and the output end of the first power amplifier circuit Main is connected to the isolation port of the circulator Cir.

[0121] The second signal Input2 is input to the input end of the fourth amplifying branch Peak1 , the output end of the fourth amplifying branch Peak1 is connected to the input port of the circulator Cir, and the output port of the circulator Cir is connected to the isolation port of the first coupler Cou2 through the matching circuit MN.

[0122] The impedance of the circulator Cir is Z01, the impedance of the first coupler Cou2 is Z02, and the matching circuit MN realizes impedance conversion between Z01 and Z02, so that the impedances of the circulator Cir and the first coupler Cou2 are matched.

[0123] The third signal Input3 is input to the first input port of the second coupler Cou1, and the second input port of the second coupler Cou1 is connected to the load; after power splitting by the second coupler Cou1, the third signal Input3 is respectively input to the input end of the fifth amplifying branch Peak2 and the input end of the sixth amplifying branch Peak2, and the output end of the fifth amplifying branch Peak2 and the output end of the sixth amplifying branch Peak2 are respectively connected to the two balanced ports of the first coupler Cou2.

[0124] The output port of the first coupler Cou2 outputs the power-synthesized signal through the matching circuit Post MN.

[0125] The output port of the first coupler Cou2 is subjected to the matching circuit Post MN to achieve impedance conversion from Z02 to 50 ohms.

[0126] When the power is low, only Main operates until Main is saturated. Peak1 then operates and Main remains in a saturated state until both Main and Peak1 are saturated. Peak2 then operates and Main and Peak1 remain in a saturated state until Main, Peak1, and Peak2 are all saturated. Therefore, the load modulation ratio of Main is equal to 1. The power amplifier device provided in this embodiment can generate three high-efficiency points, which are described in detail below in conjunction with the efficiency curve.

[0127] See FIG13 , which is a schematic diagram of the efficiency curve corresponding to FIG12 .

[0128] For example, taking Main:Peak1:Peak2:Peak2=100w:300w:600w:600w as an example, as shown in FIG13 , three high efficiency points are generated at 62dBm, 56dBm, and 50dBm, respectively, achieving a large back-off of 12dB.

[0129] Similarly, in FIG12 , the first power amplifier circuit can be implemented by a single-tube power amplifier as well as a DHT, Chireix, LMBA, or CLMA power amplifier. The broadband characteristics further depend on the broadband characteristics of the power amplifier connected to the isolation port 3 of the circulator Cir.

[0130] Based on the power amplifier device provided in the above embodiment, the embodiment of the present application further provides a radio remote unit. For details, please continue to refer to Figure 1, which is a schematic diagram of a radio remote unit provided in the embodiment of the present application.

[0131] The radio remote unit provided in this embodiment includes the power amplifier device described in the above embodiment, and further includes: a duplexer 100;

[0132] One end of the power amplifier PA is connected to the duplexer 100. Specifically, the duplexer 100 is connected between the antenna Ant and the base station power amplifier PA, and at the same time, the duplexer 100 is connected between the antenna Ant and the low noise amplifier LNA.

[0133] In addition, referring to FIG1 , the radio remote unit 1000 may further include an LNA, an ADC, and a DAC.

[0134] The radio frequency remote unit provided in the embodiment of the present application includes the power amplifier device described in the above embodiment, which is suitable for the input of up to three signals and uses a mixed cascade of a coupler and a circulator for power synthesis. The coupler can be used as the unit for the last stage of power synthesis, or the circulator can be used as the unit for the last stage of power synthesis. The power amplifier device can generate at least three high-efficiency points. Since there are many high-efficiency points, the efficiency pit problem during large back-off can be improved. Moreover, the operating bandwidth of the power amplifier device depends on the operating bandwidth of the first power amplifier circuit, the coupler, and the circulator, which can realize ultra-wideband high-power signal processing.

[0135] Based on the power amplifier device and radio remote unit provided in the above embodiments, the embodiments of the present application further provide a base station, which will be described in detail below with reference to the accompanying drawings.

[0136] See Figure 14, which is a schematic diagram of a base station provided in an embodiment of the present application.

[0137] The embodiment of the present application further provides a base station 2000, comprising the radio remote unit 1000 described in the above embodiment, and further comprising: an antenna Ant;

[0138] The radio remote unit 1000 is connected to the antenna Ant;

[0139] The radio remote unit 1000 is used to process the transmit and receive signals of the antenna Ant.

[0140] The base station provided in the embodiment of the present application, since it includes the power amplifier device 200 introduced in the above embodiment, can achieve multiple high efficiency points, improve the large pits during fallback, and is suitable for high-power scenarios, and can realize ultra-wideband high-power signal processing.

[0141] It should be understood that in this application, "at least one (item)" means one or more, and "more" means two or more. Any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this application without departing from the content of the technical solution of this application shall still fall within the scope of protection of the technical solution of this application.

Claims

1. A power amplifier device, characterized in that: include: a first power amplifier circuit, a second power amplifier circuit, a third power amplifier circuit, a first coupler, and a circulator; The input end of the first power amplifier circuit is used to connect to the first signal, the input end of the second power amplifier circuit is used to connect to the second signal, the output end of the first power amplifier circuit and the output end of the second power amplifier circuit are both connected to the input end of the first coupler, and the first coupler is used to output the power-synthesized signal; The input end of the third power amplifier circuit is used to connect a third signal, the output end of the first coupler and the output end of the third power amplifier circuit are connected to the circulator, and the circulator is used to synthesize the power of the signal output by the third power amplifier circuit and the signal output by the coupler and then output them.

2. A power amplifier device, characterized in that: include: a first power amplifier circuit, a second power amplifier circuit, a third power amplifier circuit, a first coupler, and a circulator; The input end of the first power amplifier circuit is used to connect to the first signal, the input end of the second power amplifier circuit is used to connect to the second signal, the output end of the first power amplifier circuit and the output end of the second power amplifier circuit are both connected to the circulator, and the circulator is used to output the power-synthesized signal; The input end of the third power amplifier circuit is used to connect to a third signal, the output end of the circulator and the output end of the third power amplifier circuit are connected to the first coupler, and the first coupler is used to combine the power of the signal output by the third power amplifier circuit and the signal output by the circulator and then output them.

3. The power amplifier device according to claim 1, characterized in that: The second power amplifier circuit includes a first amplifying branch and a second amplifying branch; the third power amplifier circuit includes a third amplifying branch; The first amplifying branch and the second amplifying branch are identical and both are biased in shallow class C; The third amplifying branch is biased in deep class C.

4. The power amplifier device according to claim 3, characterized in that: The first power amplifier circuit includes a single-tube power amplifier, which is a carrier power amplifier when biased in class AB or class B; and further includes: a second coupler and a matching circuit; The input end of the carrier power amplifier is used to input the first signal, and the output end of the carrier power amplifier is connected to the isolation port of the first coupler; The first input port of the second coupler is used to input the second signal, and the second input port of the second coupler is connected to a load; the first input port of the second coupler is used to connect the second signal, and the second input port of the second coupler is used to connect the load; the two output ends of the second coupler are respectively connected to the input end of the first amplifying branch and the input end of the second amplifying branch, and the output end of the first amplifying branch and the output end of the second amplifying branch are respectively connected to the two balanced ports of the first coupler; The output port of the first coupler is connected to the first end of the matching circuit, and the second end of the matching circuit is connected to the isolation port of the circulator; The input end of the third amplifying branch is used to input the third signal, the output end of the third amplifying branch is connected to the input port of the circulator, and the output port of the circulator is used to output a signal obtained by synthesizing the signal powers of the isolation port and the input port.

5. The power amplifier device according to claim 3 or 4, characterized in that: The load-pull ratio of the first power amplifier circuit is 1.

6. The power amplifier device according to claims 3-5, characterized in that: Also includes: a first power dividing circuit and a first phase compensation network; The first power dividing circuit is used to output the first signal and the second signal. One end of the first power dividing circuit outputting the first signal is connected to the input end of the first phase compensation network, the output end of the first phase compensation network is connected to the input end of the carrier power amplifier, and one end of the first power dividing circuit outputting the second signal is connected to the first input port of the second coupler.

7. The power amplifier device according to claim 6, characterized in that: Also includes: a second power dividing circuit and a second phase compensation network; The two output ends of the second power dividing circuit are respectively connected to the input end of the first power dividing circuit and the input end of the second phase compensation network; The output end of the second phase compensation network is connected to the input end of the third amplifying branch.

8. The power amplifier device according to claim 2, characterized in that: The first power amplifier circuit is a single-tube power amplifier, which is a carrier power amplifier when biased in class AB or class B; the second power amplifier circuit includes a fourth amplifying branch; the third power amplifier circuit includes a fifth amplifying branch and a sixth amplifying branch; The fourth amplifying branch is biased in shallow C class, and the fifth amplifying branch and the sixth amplifying branch are the same and are both biased in deep C class.

9. The power amplifier device according to claim 2, characterized in that: Also includes: a second coupler, a first matching circuit, and a second matching circuit; The input end of the first power amplifier circuit is used to input the first signal, and the output end of the first power amplifier circuit is connected to the isolation port of the circulator; The input end of the fourth amplifying branch is used to connect to the second signal, the output end of the fourth amplifying branch is connected to the input port of the circulator, the output port of the circulator is connected to the first end of the first matching circuit, and the second end of the first matching circuit is connected to the isolation port of the first coupler; The first input port of the second coupler is used to connect to the third signal, and the second input port of the second coupler is connected to a load; the first input port of the second coupler is used to connect to the third signal, and the second input port of the second coupler is used to connect to a load; the input end of the fifth amplifying branch and the input end of the sixth amplifying branch are respectively connected to the two output ends of the second coupler, and the output end of the fifth amplifying branch and the output end of the sixth amplifying branch are respectively connected to the two balanced ports of the first coupler; The output port of the first coupler is connected to the first end of the second matching circuit, and the output end of the second matching circuit is used to output the power-synthesized signal.

10. The power amplifier device according to claim 1 or 2, characterized in that: The first power amplifier circuit includes any one of the following: a Doherty power amplifier, a Chireix power amplifier, an LMBA power amplifier or a CLMA power amplifier.

11. The power amplifier device according to any one of claims 1 to 4, characterized in that: The first power amplifier circuit works first, the second power amplifier circuit works later, and the third power amplifier circuit works last.

12. A radio remote unit, characterized in that: The power amplifier device according to any one of claims 1 to 11 further comprises: a duplexer; One end of the power amplifier device is connected to the duplexer.

13. A base station, characterized in that: The radio remote unit according to claim 12 further comprises: an antenna; The radio remote unit is connected to the antenna; The radio remote unit is used to process the transmitting and receiving signals of the antenna.

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