Doherty power amplifier

Abstract

The embodiment of the invention discloses a Doherty power amplifier, which is characterized in that an adjusting power supply circuit at the output end of a main power amplification circuit is arranged on a main circuit in the Doherty power amplifier, and an adjusting power supply circuit at the output end of an auxiliary power amplification circuit is arranged on an auxiliary circuit. Adjacent channel leakage ratio (ACLR) of the primary path or the secondary path is adjusted to improve linearity of the Doherty power amplifier.

Description

Technical Field

[0001] The present application relates to the field of power amplifiers, and in particular to a Doherty power amplifier. Background Art

[0002] With the rapid construction of communication networks, the demand for mobile communication base stations has increased significantly. The bandwidth of instantaneous communication signals that communication base stations need to process has expanded dramatically, so as to provide faster download rates. For example, the power consumption required for the fifth-generation (5G) communication base station will be 3 to 4 times that of the fourth-generation (4G) communication network. Therefore, the high power consumption of communication base stations has become one of the main obstacles to the large-scale deployment of communication networks.

[0003] As the bandwidth of communication signals increases, the bandwidth performance of power amplifiers in communication base stations, such as single-carrier 100 megahertz (MHz) or dual-carrier 100 MHz carrier configurations, faces higher linearity requirements. The Doherty power amplifier, a low-power and high-efficiency solution widely used in communication base stations, will show obvious limitations when facing bandwidth requirements. This problem is more prominent when communication base stations pursue miniaturization, high efficiency and standardization. In other words, when the communication system adopts a small resource digital system, there are often not many digital resources for linearization correction.

[0004] Due to the above-mentioned shortcomings of the Doherty power amplifier, it exhibits obvious performance bottlenecks when processing signals in communication networks. Therefore, it is urgent to improve it to meet the requirements of high integration, standardization, high bandwidth and high efficiency of base stations. Summary of the invention

[0005] The embodiment of the present application provides a Doherty power amplifier capable of improving linearity.

[0006] The embodiment of the present application discloses a Doherty power amplifier, comprising:

[0007] The input signal is divided into a main signal and an auxiliary signal by a signal distribution circuit 1, and transmitted to the main signal and the auxiliary signal respectively; in the main signal, the main signal is transmitted to a synthesis circuit 8 after being input impedance matched by a main input matching circuit 2, amplified by a main power amplifier circuit 3, and output impedance matched by a main output matching circuit 4; in the auxiliary signal, the auxiliary signal is transmitted to the synthesis circuit 8 after being input impedance matched by an auxiliary input matching circuit 5, amplified by an auxiliary power amplifier circuit 6, and output impedance matched by an auxiliary output matching circuit 7; the synthesis circuit 8 synthesizes the processed main signal and the auxiliary signal and outputs them; the Doherty power amplifier also includes:

[0008] A regulating power supply circuit 14 is connected to the output end of the main power amplifier circuit between the main power amplifier circuit 3 and the main output matching circuit 4, and adjusts the adjacent channel leakage ratio ACLR of the main circuit while supplying power to the main circuit;

[0009] A regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit is connected between the auxiliary power amplifier circuit 6 and the auxiliary output matching circuit 7 to regulate the ACLR of the auxiliary circuit while supplying power to the auxiliary circuit.

[0010] The embodiment of the present application further includes: a main pre-matching circuit 10 connected in series between the main power amplifier circuit 3 and the main output matching circuit 4, providing harmonic impedance for the second harmonic of the signal after power amplification processing of the main path, and a regulating power supply circuit 14 at the output end of the main power amplifier circuit is connected between the main pre-matching circuit 10 and the main output matching circuit 4;

[0011] The auxiliary pre-matching circuit 12 connected in series between the auxiliary power amplifier circuit 6 and the auxiliary output matching circuit 7 provides harmonic impedance for the second harmonic of the signal after power amplification processing of the auxiliary circuit, and the regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit is connected between the auxiliary pre-matching circuit 12 and the auxiliary output matching circuit 7.

[0012] In the embodiment of the present application, the regulating power supply circuit 14 at the output end of the main power amplifier circuit or the regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit includes: an ACLR balancing subcircuit 501 and a power supply peripheral subcircuit 502, wherein:

[0013] The power supply peripheral sub-circuit 502 is connected between the main power amplifier circuit 3 and the main output matching circuit 4, or between the auxiliary power amplifier circuit 6 and the auxiliary output matching circuit 7, and loads the power supply after RF isolation and load impedance on the main circuit or the auxiliary circuit;

[0014] An ACLR balancing subcircuit 501 is connected between two inductance elements in the power supply peripheral subcircuit 502 to adjust the ACLR of the main circuit or the ACLR of the auxiliary circuit.

[0015] In the embodiment of the present application, the power supply peripheral sub-circuit 502 includes:

[0016] The inductor (L502-1) and the inductor (L502-2) connected in series are connected to the power supply terminal (VDD) to supply power to the main circuit or the auxiliary circuit, and provide load impedance for the main circuit or the auxiliary circuit;

[0017] A radio frequency bypass capacitor C502-1 is connected between the inductor L502-1 and the inductor L502-2 to provide radio frequency isolation for the power supply;

[0018] A decoupling capacitor C502 - 2 is connected between the inductor L502 - 2 and the power supply terminal VDD to decouple the power supply.

[0019] In the embodiment of the present application, the ACLR balancing subcircuit 501 includes:

[0020] The capacitor C101 and the variable resistor RH101 are connected in series and then grounded, and a pull-up resistor R101 is connected between the capacitor C101 and the variable resistor RH101;

[0021] Alternatively, the capacitor C102, the resistor R102 and the variable capacitor VC101 are connected in series and then grounded, and a pull-up resistor R103 is connected between the resistor R102 and the variable capacitor VC101;

[0022] Alternatively, capacitor C103, variable resistor RH102 and variable capacitor VC102 are connected in series and then grounded, a pull-up resistor R104 is provided between capacitor C103 and variable resistor RH102, and a pull-up resistor R105 is provided between variable resistor RH102 and variable capacitor VC102;

[0023] Alternatively, the capacitor C104 and the variable resistor RH103 are connected in series and then grounded, a pull-up resistor R106 is connected between the capacitor C104 and the variable resistor RH103, and the variable resistor RH103 is connected in parallel with the capacitor C105;

[0024] Alternatively, capacitor C106, variable resistor RH104 and variable capacitor VC103 are connected in series and then grounded, a pull-up resistor R107 is connected between capacitor C106 and variable resistor RH104, a pull-up resistor R108 is connected between variable resistor RH104 and variable capacitor VC103, and variable resistor RH104 is connected in parallel with capacitor C107;

[0025] Alternatively, capacitor C108 and resistor R109 are connected in series and then grounded;

[0026] Alternatively, the resistor R110 and the capacitor C109 are connected in series and then grounded;

[0027] Alternatively, the inductor L101, the capacitor C110 and the resistor R111 are connected in series and then grounded;

[0028] Alternatively, the capacitor C111, the inductor L102, and the resistor R112 are connected in series and then grounded.

[0029] In the embodiment of the present application, the synthesis circuit 8 includes: a phase adjustment circuit, which adjusts the phase of the auxiliary signal after output impedance matching to be aligned with the phase of the main signal after output impedance matching, wherein the adjusted signal and the phase-aligned signal are output through the same node;

[0030] Alternatively, the phase of the main signal after output impedance matching is adjusted to be aligned with the phase of the auxiliary signal after output impedance matching.

[0031] Further, the synthesis circuit 8 includes: a phase compensation line element, used to adjust the phase of the auxiliary signal after output impedance matching to be aligned with the phase of the main signal after output impedance matching; or, used to adjust the phase of the main signal after output impedance matching to be aligned with the phase of the auxiliary signal after output impedance matching, and an impedance transformer, used to perform impedance transformation on the main signal before or after phase adjustment;

[0032] Alternatively, impedance transformation is performed on the auxiliary signal before or after phase adjustment, wherein the adjusted signal and the phase-aligned signal are output via the same node.

[0033] As can be seen above, the embodiment of the present application sets a regulating power supply circuit at the output end of the main power amplifier circuit in the main circuit of the Doherty power amplifier, and sets a regulating power supply circuit at the output end of the auxiliary power amplifier circuit in the auxiliary circuit. While supplying power to the main circuit or the auxiliary circuit, the adjacent channel leakage ratio (ACLR) of the main circuit or the auxiliary circuit is adjusted, thereby improving the linearity of the Doherty power amplifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of the basic structure of a Doherty power amplifier provided in an embodiment of the present application;

[0035] Figure 2-1a A structural diagram of a specific implementation example 1 of the signal distribution circuit 1 provided in an embodiment of the present application;

[0036] Figure 2-1b A structural diagram of a specific implementation example 2 of the signal distribution circuit 2 provided in an embodiment of the present application;

[0037] Figure 2-2 A structural diagram of a specific implementation example of the main input matching circuit 2 or the auxiliary input matching circuit 5 provided in an embodiment of the present application;

[0038] Figure 2-3 A structural diagram of a specific implementation example of the main output matching circuit 4 or the auxiliary output matching circuit 7 provided in an embodiment of the present application;

[0039] Figure 2-4 A structural diagram of a specific implementation example of the main pre-matching circuit 10 or the auxiliary pre-matching circuit 12 provided in an embodiment of the present application;

[0040] Figure 2-5 A schematic diagram of a structure of a specific implementation example of a power supply circuit 11 at the output end of a main power amplifier circuit or a power supply circuit 13 at the output end of an auxiliary power amplifier circuit provided in an embodiment of the present application;

[0041] Figure 3 A schematic diagram of the structure of an example 1 of a Doherty power amplifier provided in an embodiment of the present application;

[0042] Figure 4 A schematic diagram of the structure of Example 2 of the Doherty power amplifier provided in an embodiment of the present application;

[0043] Figure 5 A structural diagram of a specific implementation example of a regulating power supply circuit 14 at the output end of a main power amplifier circuit or a regulating power supply circuit 15 at the output end of an auxiliary power amplifier circuit provided in an embodiment of the present application;

[0044] Figure 6-1 to Figure 6-9 Nine specific implementation circuit structure diagrams of the ACLR balancing sub-circuit 501 provided in the embodiments of the present application;

[0045] Figure 7 A schematic diagram of a structure of a specific implementation of a Doherty power amplifier provided in an embodiment of the present application;

[0046] Figure 8 A schematic diagram of the structure of the Doherty power amplifier provided in the embodiment of the present application;

[0047] Fig. 9 A schematic diagram of the structure of a Doherty power amplifier according to an embodiment of the present application;

[0048] Fig.10 This is a schematic diagram of the structure of Example 5 of the Doherty power amplifier provided in an embodiment of the present application. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0050] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0051] The technical solution of the present application is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0052] The present application embodiment first briefly describes the structure of the existing Doherty power amplifier. Figure 1 As shown, Figure 1 A schematic diagram of the basic structure of a Doherty power amplifier provided in an embodiment of the present application, wherein the Doherty power amplifier comprises:

[0053] A signal distribution circuit 1, which divides the input signal to be amplified into a main channel signal and an auxiliary channel signal, and transmits the main channel signal to the main channel and transmits the auxiliary channel signal to the auxiliary channel;

[0054] In the main path, the main path signal is transmitted to the synthesis circuit 8 after being input impedance matched by the main input matching circuit 2, amplified by the main power amplifier circuit 3, and output impedance matched by the main output matching circuit 4;

[0055] In the auxiliary path, the auxiliary path signal is transmitted to the synthesis circuit 8 after the input impedance matching of the auxiliary input matching circuit 5, the amplification of the auxiliary power amplifier circuit 6, and the output impedance matching of the auxiliary output matching circuit 7;

[0056] The main signal after the power amplification processing of the main path and the auxiliary signal after the power amplification processing of the auxiliary path are synthesized by the synthesis circuit 8 and output.

[0057] The main power amplifier circuit 3 is a class AB power amplifier circuit, and the auxiliary power amplifier circuit 6 is a class C power amplifier circuit.

[0058] The peripheral circuit of the Doherty power amplifier further includes: a back-end impedance circuit 9 for performing impedance transformation on the synthesized signal output by the synthesizing circuit 8. Specifically, the back-end impedance circuit 9 can be implemented by an impedance converter 91.

[0059] Here, the signal distribution circuit 1 includes: a power divider or coupler 11, and a first phase adjustment circuit 12, wherein the power divider or coupler 11 divides the input signal into two signals, one is a main signal, and the other is an auxiliary signal; the first phase adjustment circuit 12 adjusts the phase of the auxiliary signal to a certain degree and inputs it into the auxiliary signal, and the adjustment setting degree can be delayed by 90 degrees or advanced by 90 degrees, which is not limited here; or, the first phase adjustment circuit 12 adjusts the phase of the main signal to a certain degree and inputs it into the main signal, and the adjustment setting degree can be delayed by 90 degrees or advanced by 90 degrees. The above two access methods are as follows: Figure 2-1a and Figure 2-1b In the following description, Figure 2-1b The signal distribution circuit 1 shown is described for a specific embodiment. It is understandable that the embodiment of the present application can also be used as Figure 2-1a The implementation of the signal distribution circuit 1 shown is not limited in the embodiment of the present application.

[0060] The main input matching circuit 2 or the auxiliary input matching circuit 5 can be composed of a capacitor and an inductor, as shown in the specific example. Figure 2-2 As shown, Figure 2-2 The schematic diagram of the structure of the main input matching circuit 2 or the auxiliary input matching circuit 5 provided in the embodiment of the present application includes: a capacitor C21 and an inductor L21 connected in series, a grounding capacitor C22 is connected between the capacitor C21 and the inductor L21, and a grounding capacitor C23 is connected at the output end of the inductor L21. Among them, the capacitor C21 is used for RF coupling and DC bias isolation, and also acts as a part of the input impedance matching when necessary. The inductor L21, the grounding capacitor C22 and the grounding capacitor C23 are used to match the input impedance of the main signal or the auxiliary signal. The implementation method of the inductor L21 includes the use of distributed devices such as microstrip lines or strip lines connected in series, and the implementation method of the grounding capacitor C22 and the grounding capacitor C23 includes the use of distributed devices such as open microstrip line branches and open strip lines in parallel.

[0061] The main power amplifier circuit 3 or the auxiliary power amplifier circuit 6 includes a metal oxide semiconductor field effect transistor (MOS), which may be specifically a gallium nitride (GaN) MOS.

[0062] The input end of the main power amplifier circuit 3 or the auxiliary power amplifier circuit 6 can also be pulled up to the bias voltage 1 or the bias voltage 2 through the pull-up impedance converter 91, thereby improving the input signal performance of the main power amplifier circuit 3 or the auxiliary power amplifier circuit 6 while providing power supply.

[0063] The main output matching circuit 4 or the auxiliary output matching circuit 7 can be composed of an impedance converter 91 connected in series with a capacitor C41. Figure 2-3 shown.

[0064] The synthesis circuit 8 at least includes: a second phase adjustment circuit 81, which adjusts the phase of the auxiliary signal after output impedance matching to align with the phase of the main signal after output impedance matching. Here, the phase adjustment of the auxiliary signal after output impedance matching can be advanced by 90 degrees.

[0065] In the main path of the Doherty power amplifier, a main pre-matching circuit 10 is connected in series between the main power amplification circuit 3 and the main output matching circuit 4 to provide a suitable harmonic impedance for the second harmonic of the signal after power amplification processing in the main path.

[0066] In the auxiliary circuit of the Doherty power amplifier, an auxiliary pre-matching circuit 12 is also connected in series between the auxiliary power amplification circuit 6 and the auxiliary output matching circuit 7 to provide a suitable harmonic impedance for the second harmonic of the signal after power amplification processing in the auxiliary circuit.

[0067] The specific implementation examples of the main pre-matching circuit 10 or the auxiliary pre-matching circuit 12 are as follows: Figure 2-4 As shown, it includes: an inductor L11 connected in series between the main power amplifier circuit 3 and the main output matching circuit 4, or between the auxiliary power amplifier circuit 6 and the auxiliary output matching circuit 7, and the inductor L11 is pulled down to ground through the series inductor L12 and capacitor C11 to provide suitable harmonic impedance for the second harmonic of the signal after power amplification processing of the main circuit or the auxiliary circuit.

[0068] In the main circuit of the Doherty power amplifier, a power supply circuit 11 at the output end of the main power amplifier circuit is connected between the main pre-matching circuit 10 and the main output matching circuit 4 to provide power supply to the main circuit and drive the load impedance of the main circuit.

[0069] In the auxiliary circuit of the Doherty power amplifier, a power supply circuit 13 at the output end of the auxiliary power amplifier circuit is connected between the auxiliary pre-matching circuit 12 and the auxiliary output matching circuit 7 to provide power supply to the auxiliary circuit and drive the load impedance of the auxiliary circuit.

[0070] The specific implementation example of the power supply circuit 11 at the output end of the main power amplifier circuit or the power supply circuit 13 at the output end of the auxiliary power amplifier circuit is as follows: Figure 2-5 As shown, it includes: equivalent inductor L1111, decoupling capacitor C1111 and RF bypass capacitor C1112. The power supply terminal VDD is connected between the main pre-matching circuit 10 and the main output matching circuit 4, or between the auxiliary pre-matching circuit 12 and the auxiliary output matching circuit 7 through the equivalent inductor L1111, the power supply is loaded into the main circuit or the auxiliary circuit, and load impedance is provided for the main circuit or the auxiliary circuit; the decoupling capacitor C1111 and the RF bypass capacitor C1112 are connected in parallel between the power supply VDD and the equivalent inductor L1111 to provide RF isolation for the power supply.

[0071] Combined with the above Figure 1 ,and Figure 2-1b , Figure 2-3 - Figure 2-5 The structure described above forms Figure 3 The schematic diagram of the structure of the Doherty power amplifier is shown in FIG. Of course, the Doherty power amplifier can also be implemented in other forms. Figure 3 As an example, the implementation of the present application is described in detail.

[0072] Figure 3 In the Doherty power amplifier shown, impedance adaptation problems are prone to occur between the main power amplifier circuit 3 and the power supply circuit 11 at the output end of the main power amplifier circuit, or between the auxiliary power amplifier circuit 6 and the power supply circuit 13 at the output end of the power amplifier circuit, and as the bandwidth increases, the frequency change between the frequencies will cause the adjacent channel spectrum to change, thereby causing the ACLR of the Doherty power amplifier to deteriorate and affecting the linearity of the Doherty power amplifier. In some applications, there may even be stability problems, such as the formation of self-excited oscillation.

[0073] Furthermore, when the frequency and power in the band change, the output parasitic capacitance of the main power amplifier circuit 3 or the auxiliary power amplifier circuit 6 in the Doherty power amplifier will also change. These changes will deteriorate the ACLR, further exacerbating the nonlinear distortion problem of the Doherty power amplifier in broadband applications.

[0074] Among them, ACLR is used to measure the degree of power leakage of communication base stations on adjacent channels. In wireless communication systems, communication base stations need to send signals on specific frequencies, but inevitably generate a certain degree of power leakage on adjacent channels. This leakage may interfere with communications on adjacent channels. ACLR is an important performance indicator because it is directly related to whether the wireless communication system can effectively avoid interference between channels. A lower ACLR means that the power of the communication base station is more concentrated on the main channel, causing less interference to adjacent channels. This is crucial to ensuring the quality and efficiency of wireless communications.

[0075] The applicant has found that in the Doherty power amplifier, the main power amplifier circuit 3 or the auxiliary power amplifier circuit 6, the main input matching circuit 2 or the auxiliary input matching circuit 5, and the output matching circuit 4 or the auxiliary output matching circuit 7 can all be improved to adjust the ACLR. However, since the above-mentioned circuits must also take into account radio frequency indicators such as power and efficiency when the Doherty power amplifier is in operation, it is impossible to improve the circuit only for ACLR. Therefore, the embodiment of the present application improves the power supply circuit 11 at the output end of the main power amplifier circuit and the power supply circuit 13 at the output end of the power amplifier circuit to reduce their negative impact on the Doherty power amplifier during power supply, and adjusts the ACLR to avoid deterioration of the ACLR, thereby improving the linearity of the Doherty power amplifier.

[0076] Figure 4 The second structural diagram of the Doherty power amplifier provided in the embodiment of the present application is as follows: Figure 4 As shown, Benshen Figure 3 In the structure of the Doherty power amplifier shown in the figure, a regulating power supply circuit 14 at the output end of the main power amplifier circuit and a regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit are provided to replace the power supply circuit 11 at the output end of the main power amplifier circuit and the power supply circuit 13 at the output end of the auxiliary power amplifier circuit, wherein:

[0077] The regulating power supply circuit 14 at the output end of the main power amplifier circuit adjusts the ACLR of the main circuit while supplying power to the main circuit.

[0078] The regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit adjusts the ACLR of the auxiliary circuit while supplying power to the auxiliary circuit.

[0079] In the embodiment of the present application, in the Doherty power amplifier, an adjustment power supply circuit 14 at the output end of the main power amplifier circuit is connected between the main power amplifier circuit 3 and the main output matching circuit 4, and while supplying power to the main circuit, the ACLR of the adjacent channel power spectrum of the main circuit is adjusted;

[0080] A regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit is connected between the auxiliary power amplifier circuit 6 and the auxiliary output matching circuit 7 to regulate the ACLR of the auxiliary circuit while supplying power to the auxiliary circuit.

[0081] Specifically, in the Doherty power amplifier, the regulating power supply circuit 14 at the output end of the main power amplifier circuit is connected between the main pre-matching circuit and the main output matching circuit 4;

[0082] The regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit is connected between the auxiliary pre-matching circuit 12 and the main output matching circuit 14 .

[0083] In the embodiment of the present application, the regulating power supply circuit 14 at the output end of the main power amplifier circuit and the regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit have the same structure, and their specific structures are as follows: Figure 5 As shown, it includes an ACLR balancing sub-circuit 501 and a power supply peripheral sub-circuit 502, wherein:

[0084] A power supply peripheral sub-circuit 502 is connected between the main power amplifier circuit 3 and the main output matching circuit 4, or between the auxiliary power amplifier circuit 6 and the auxiliary output matching circuit 7, and the power supply after radio frequency isolation and load impedance is loaded on the main circuit or the auxiliary circuit;

[0085] An ACLR balancing subcircuit 501 is connected between two inductance elements in the power supply external network subcircuit 502 to adjust the ACLR of the main circuit or the auxiliary circuit.

[0086] Specifically, the power supply peripheral sub-circuit 502 includes:

[0087] The main power amplifier circuit 3 and the main output matching circuit 4 are connected to the power supply terminal VDD via the inductor L502-1 and the inductor L502-2 connected in series, supplying power to the main circuit or the auxiliary circuit, and providing load impedance for the main circuit or the auxiliary circuit;

[0088] A radio frequency bypass capacitor C502-1 is connected between the inductor L502-1 and the inductor L502-2 to provide radio frequency isolation for the power supply;

[0089] A decoupling capacitor C502-2 is connected between the inductor L502-2 and the power supply terminal VDD to decouple the power supply.

[0090] An ACLR balancing sub-circuit 501 is also connected between the inductor L502 - 1 and the inductor L502 - 2 to adjust the ACLR of the power supply.

[0091] In this way, since the power supplies of the main circuit and the auxiliary circuit of the Doherty power amplifier are ACLR regulated, they will not cause the ACLR of the Doherty power amplifier to deteriorate in the working state, thereby improving the linearity of the Doherty power amplifier.

[0092] In the embodiment of the present application, the ACLR balancing sub-circuit 501 is composed of at least one capacitor and one resistor. In specific implementation, there are 9 implementation methods of the ACLR balancing sub-circuit 501. Figure 6-1 to Figure 6-9 These are nine specific implementation circuit structure diagrams of the ACLR balancing sub-circuit 501 provided in the embodiments of the present application, which are described below respectively.

[0093] Figure 6-1 In the first implementation method shown, the ACLR balancing subcircuit 501 includes:

[0094] The capacitor C101 and the variable resistor RH101 are connected in series and then grounded, and a pull-up resistor R101 is connected between the capacitor C101 and the variable resistor RH101.

[0095] Figure 6-2 In the second implementation method shown, the ACLR balancing subcircuit 501 includes:

[0096] The capacitor C102, the resistor R102 and the variable capacitor VC101 are connected in series and then grounded, and a pull-up resistor R103 is connected between the resistor R102 and the variable capacitor VC101.

[0097] Figure 6-3In the third implementation method shown, the ACLR balancing sub-circuit 501 includes:

[0098] Capacitor C103, variable resistor RH102 and variable capacitor VC102 are connected in series and then grounded. A pull-up resistor R104 is provided between capacitor C103 and variable resistor RH102, and a pull-up resistor R105 is provided between variable resistor RH102 and variable capacitor VC102.

[0099] Figure 6-4 In the fourth implementation method shown, the ACLR balancing sub-circuit 501 includes:

[0100] The capacitor C104 and the variable resistor RH103 are connected in series and then grounded, a pull-up resistor R106 is connected between the capacitor C104 and the variable resistor RH103, and the variable resistor RH103 is connected in parallel with the capacitor C105.

[0101] Figure 6-5 In the fifth implementation method shown, the ACLR balancing subcircuit 501 includes:

[0102] Capacitor C106, variable resistor RH104 and variable capacitor VC103 are connected in series and then grounded, a pull-up resistor R107 is connected between capacitor C106 and variable resistor RH104, a pull-up resistor R108 is connected between variable resistor RH104 and variable capacitor VC103, and variable resistor RH104 is connected in parallel with capacitor C107.

[0103] Figure 6-6 In the sixth implementation method shown, the ACLR balancing subcircuit 501 includes:

[0104] Capacitor C108 and resistor R109 are connected in series and then grounded.

[0105] Figure 6-7 In the seventh implementation method shown, the ACLR balancing subcircuit 501 includes:

[0106] The resistor R110 and the capacitor C109 are connected in series and then grounded.

[0107] Figure 6-8 In the eighth implementation method shown, the ACLR balancing subcircuit 501 includes:

[0108] The inductor L101, the capacitor C110 and the resistor R111 are connected in series and then grounded.

[0109] Figure 6-9 In the ninth implementation method shown, the ACLR balancing subcircuit 501 includes:

[0110] The capacitor C111, the inductor L102, and the resistor R112 are connected in series and then grounded.

[0111] In the present embodiment, Figure 5 The structure shown is applied in Figure 4 In the Figure 7 The structure diagram of a specific implementation of the Doherty power amplifier is shown.

[0112] In the embodiments of the present application, Figure 3 The structure of the example 1 of the Doherty power amplifier shown is an implementation of the Doherty power amplifier. The structure of the Doherty power amplifier can be varied, and these varied structures include a regulating power supply circuit 14 at the output end of the main power amplifier circuit and a regulating power supply circuit 15 at the output end of the auxiliary power amplifier circuit.

[0113] Figure 8 The third structural diagram of the Doherty power amplifier provided in the embodiment of the present application is shown in FIG. Figure 4 or Figure 7 Compared with the above, the connection mode of the synthesis circuit 8 is different. The second phase adjustment circuit 81 included therein is used to adjust the phase of the main signal after output impedance matching to be aligned with the phase of the auxiliary signal after output impedance matching. Here, the phase adjustment of the main signal after output impedance matching can be delayed by 90 degrees. The auxiliary signal, i.e., the phase-aligned signal, and the main signal after phase alignment, i.e., the adjusted signal, are input to the back-end impedance circuit 9 through the same node and output after the back-end impedance circuit 9, wherein the phase-aligned signal and the adjusted signal are superimposed at the node.

[0114] Fig. 9 The fourth structural diagram of the Doherty power amplifier provided in the embodiment of the present application is shown in FIG. Figure 4 or Figure 7 Compared with the above, the structure of the synthesis circuit 8 is different. Fig. 9 The synthesis circuit 8 includes: an impedance converter and a phase compensation line element, wherein the phase compensation line element is used to adjust the phase of the auxiliary signal after output impedance matching to be aligned with the phase of the main signal after output impedance matching; the impedance converter is used to perform impedance conversion on the auxiliary signal before phase adjustment. The main signal, i.e., the phase-aligned signal, and the auxiliary signal after phase alignment, i.e., the adjusted signal, are input to the back-end impedance circuit 9 through the same node and output after the back-end impedance circuit 9, wherein the phase-aligned signal and the adjusted signal are superimposed at the node.

[0115] Fig.10 The fifth structural diagram of the Doherty power amplifier provided in the embodiment of the present application is shown in FIG. Figure 4 or Figure 7 Compared with the above, the structure of the synthesis circuit 8 is different. Fig.10The synthesis circuit 8 shown includes: an impedance converter and a phase compensation line element, wherein the phase compensation line element is used to adjust the phase of the main signal after output impedance matching to be aligned with the phase of the auxiliary signal after output impedance matching, where the phase adjustment of the main signal after output impedance matching can be delayed by 90 degrees; the impedance converter is used to perform impedance transformation on the main signal before phase adjustment. The auxiliary signal, i.e., the phase-aligned signal, and the main signal after phase alignment, i.e., the adjusted signal, are input to the back-end impedance circuit 9 through the same node and output after the back-end impedance circuit 9, wherein the phase-aligned signal and the adjusted signal are superimposed at the node.

[0116] In practical applications, the positions of the phase compensation line element and the impedance transformer can be exchanged, so that the impedance transformer can be used to perform impedance transformation on the phase-adjusted signal.

[0117] Those skilled in the art will appreciate that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations or combinations are not explicitly described in the present application. In particular, without departing from the spirit and teachings of the present application, the features described in the various embodiments and / or claims of the present application may be combined and / or combined in a variety of ways, and all of these combinations and / or combinations fall within the scope disclosed in the present application.

[0118] Specific embodiments are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core ideas of the present application, and is not used to limit the present application. For those skilled in the art, changes can be made in the specific implementation methods and application scopes according to the ideas, spirits and principles of the present application, and any modifications, equivalent substitutions, improvements, etc. made by them should be included in the scope of protection of the present application.

Claims

1. A Doherty power amplifier, comprising: The input signal is divided into a main signal and an auxiliary signal by a signal distribution circuit (1), and transmitted to the main channel and the auxiliary channel respectively; In the main path, the main path signal is transmitted to a synthesis circuit (8) after being input impedance matched by a main input matching circuit (2), amplified by a main power amplifier circuit (3), and output impedance matched by a main output matching circuit (4); in the auxiliary path, the auxiliary path signal is transmitted to the synthesis circuit (8) after being input impedance matched by an auxiliary input matching circuit (5), amplified by an auxiliary power amplifier circuit (6), and output impedance matched by an auxiliary output matching circuit (7); the synthesis circuit (8) synthesizes the processed main path signal and the auxiliary path signal and outputs them; It is characterized by further comprising: A regulating power supply circuit (14) is connected to the output end of the main power amplifier circuit between the main power amplifier circuit (3) and the main output matching circuit (4), and adjusts the adjacent channel leakage ratio (ACLR) of the main circuit while supplying power to the main circuit; A regulating power supply circuit (15) is connected between the auxiliary power amplifier circuit (6) and the auxiliary output matching circuit (7) to adjust the ACLR of the auxiliary circuit while supplying power to the auxiliary circuit.

2. The Doherty power amplifier according to claim 1, wherein: Also includes: A main pre-matching circuit (10) connected in series between the main power amplifier circuit (3) and the main output matching circuit (4) provides harmonic impedance for the second harmonic of the signal after power amplification processing of the main path, and a regulating power supply circuit (14) at the output end of the main power amplifier circuit is connected between the main pre-matching circuit (10) and the main output matching circuit (4); An auxiliary pre-matching circuit (12) connected in series between the auxiliary power amplifier circuit (6) and the auxiliary output matching circuit (7) provides harmonic impedance for the second harmonic of the signal after power amplification processing of the auxiliary circuit, and a regulating power supply circuit (15) at the output end of the auxiliary power amplifier circuit is connected between the auxiliary pre-matching circuit (12) and the auxiliary output matching circuit (7).

3. The Doherty power amplifier according to claim 1, wherein: The regulating power supply circuit (14) at the output end of the main power amplifier circuit or the regulating power supply circuit (15) at the output end of the auxiliary power amplifier circuit comprises: an ACLR balancing subcircuit (501) and a power supply peripheral subcircuit (502), wherein: The power supply peripheral subcircuit (502) is connected between the main power amplifier circuit (3) and the main output matching circuit (4), or between the auxiliary power amplifier circuit (6) and the auxiliary output matching circuit (7), and loads the power supply after radio frequency isolation and load impedance onto the main circuit or the auxiliary circuit; An ACLR balancing subcircuit (501) is connected between two inductance elements in the power supply peripheral subcircuit (502) to adjust the ACLR of the main circuit or the ACLR of the auxiliary circuit.

4. The Doherty power amplifier according to claim 3, wherein: The power supply peripheral sub-circuit (502) comprises: The inductor (L502-1) and the inductor (L502-2) connected in series are connected to the power supply terminal (VDD) to supply power to the main circuit or the auxiliary circuit, and provide load impedance for the main circuit or the auxiliary circuit; A radio frequency bypass capacitor (C502-1) is connected between the inductor (L502-1) and the inductor (L502-2) to provide radio frequency isolation for the power supply; A decoupling capacitor (C502-2) is connected between the inductor (L502-2) and the power supply terminal (VDD) to decouple the power supply.

5. The Doherty power amplifier according to claim 3, wherein: The ACLR balancing subcircuit (501) comprises: A capacitor (C101) and a variable resistor (RH101) are connected in series and then grounded, and a pull-up resistor (R101) is provided between the capacitor (C101) and the variable resistor (RH101); Alternatively, the capacitor (C102), the resistor (R102) and the variable capacitor (VC101) are connected in series and then grounded, and a pull-up resistor (R103) is provided between the resistor (R102) and the variable capacitor (VC101); Alternatively, the capacitor (C103), the variable resistor (RH102) and the variable capacitor (VC102) are connected in series and then grounded, a pull-up resistor (R104) is provided between the capacitor (C103) and the variable resistor (RH102), and a pull-up resistor (R105) is provided between the variable resistor (RH102) and the variable capacitor (VC102); Alternatively, the capacitor (C104) and the variable resistor (RH103) are connected in series and then grounded, a pull-up resistor (R106) is connected between the capacitor (C104) and the variable resistor (RH103), and the variable resistor (RH103) is connected in parallel with the capacitor (C105); Alternatively, the capacitor (C106), the variable resistor (RH104) and the variable capacitor (VC103) are connected in series and then grounded, a pull-up resistor (R107) is connected between the capacitor (C106) and the variable resistor (RH104), a pull-up resistor (R108) is connected between the variable resistor (RH104) and the variable capacitor (VC103), and the variable resistor (RH104) is connected in parallel with the capacitor (C107); Alternatively, the capacitor (C108) and the resistor (R109) are connected in series and then grounded; Alternatively, the resistor (R110) and the capacitor (C109) are connected in series and then grounded; Alternatively, the inductor (L101), the capacitor (C110) and the resistor (R111) are connected in series and then grounded; Alternatively, the capacitor (C111), the inductor (L102), and the resistor (R112) are connected in series and then grounded.

6. The Doherty power amplifier according to any one of claims 1 to 5, characterized in that: The synthesis circuit (8) comprises: a phase adjustment circuit, which adjusts the phase of the auxiliary signal after output impedance matching to be aligned with the phase of the main signal after output impedance matching; Alternatively, the phase of the main signal after output impedance matching is adjusted to be aligned with the phase of the auxiliary signal after output impedance matching; The adjusted signal and the phase-aligned signal are output via the same node.

7. The Doherty power amplifier according to any one of claims 1 to 5, characterized in that: The synthesis circuit (8) comprises: A phase compensation line element is used to adjust the phase of the auxiliary signal after output impedance matching to align with the phase of the main signal after output impedance matching; or to adjust the phase of the main signal after output impedance matching to align with the phase of the auxiliary signal after output impedance matching, The impedance converter is used to perform impedance conversion on the signal before or after phase adjustment; wherein the adjusted signal and the phase-aligned signal are output via the same node.

Images