Power amplifier circuits, RF front-end components, RF transceiver systems and electronic equipment

Abstract

The present application provides a power amplifier circuit, a radio frequency front-end component, a radio frequency transceiver system and an electronic device, and relates to the field of power amplifier technology. It aims to improve the problem that the power amplifier circuit has limited ability to improve the working efficiency of power points between the power saturation point and the power critical point. The power amplifier circuit includes a power divider, a first power amplifier branch, the first power amplifier branch includes a phase shift network, a second power amplifier branch, the input end of the second power amplifier branch is connected to the power divider, and the input end of the first power amplifier branch is connected to the power divider, wherein the phase shift network is used to adjust the phase difference between the output signal of the first power amplifier branch and the output signal of the second power amplifier branch according to the input signal of the power amplifier circuit, when the power of the input signal is different, the phase difference adjusted by the phase shift network is also different, and the phase shift network can dynamically adjust the phase difference according to the power change of the input signal, thereby optimizing the phase modulation of different power points and improving the working efficiency of the power amplifier circuit.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of power amplifiers, and in particular to a power amplifier circuit, a radio frequency front-end component, a radio frequency transceiver system, and an electronic device. Background Art

[0002] In modern wireless communication systems, the power amplifier (PA) is an important component. In order to improve the working efficiency of the PA in the power back-off state, a load modulated balanced amplifier (LMBA) can be selected. The load modulated balanced amplifier has the advantages of extending the bandwidth and improving the working efficiency in the back-off state.

[0003] Currently, load-modulated balanced power amplifiers have limited ability to improve operating efficiency at power points between the power saturation point and the power critical point. Summary of the invention

[0004] Embodiments of the present application provide a power amplifier circuit, a radio frequency front-end component, a radio frequency transceiver system and an electronic device, which are used to improve the problem that the power amplifier has limited ability to improve the working efficiency of power points between the power saturation point and the power critical point.

[0005] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0006] In a first aspect, the present application provides a power amplifier circuit, which includes a power divider, a first power amplifier branch, and a second power amplifier branch. The first power amplifier branch includes a phase shift network, and the input end of the first power amplifier branch is connected to the power divider. The input end of the second power amplifier branch is connected to the power divider. The phase shift network is used to adjust the phase difference between the output signal of the first power amplifier branch and the output signal of the second power amplifier branch according to the input signal of the power amplifier circuit. The power amplifier circuit inputs an input signal of a first power, and the phase difference is a first phase difference. The power amplifier circuit inputs an input signal of a second power, and the phase difference is a second phase difference. The first phase difference and the second phase difference are different.

[0007] In the above technical solution, the phase shifting network can dynamically adjust the phase difference between the output signal of the first power amplifier branch and the output signal of the second power amplifier branch according to the input signal of the power amplifier circuit, that is, the phase adjustment value provided by the phase shifting network is dynamically changing, that is, each power point between the power critical point and the power saturation point of the main power amplifier branch of the power amplifier circuit has a corresponding phase difference. Compared with the fixed phase difference, the load impedance of the main power amplifier branch of the power amplifier circuit can be optimized, thereby improving the overall working efficiency of the power amplifier circuit between the power critical point and the power saturation point.

[0008] In a feasible implementation of the first aspect, the phase shift network includes a conversion circuit and a first phase shift circuit. The input end of the conversion circuit is connected to the power divider, the output end of the conversion circuit is connected to the controlled end of the first phase shift circuit, the conversion circuit is used to provide a control signal to the first phase shift circuit according to the power of the input signal, and the first phase shift circuit is used to adjust the phase difference between the output signal of the first power amplifier branch and the output signal of the second power amplifier branch according to the control signal.

[0009] In a feasible implementation manner of the first aspect, the first power is a first interval value, the second power is a second interval value, and the first interval value and the second interval value are different.

[0010] In a feasible implementation of the first aspect, the first phase shift circuit includes a plurality of phase shift units, which are connected in series between the input and output ends of the first phase shift circuit, each phase shift unit includes a phase shift sub-circuit, a switch circuit and a comparison circuit, the first input end of the comparison circuit is connected to the controlled end of the first phase shift circuit, the second input end of the comparison circuit is connected to the reference voltage input end, the output end of the comparison circuit is connected to the controlled end of the switch circuit, the first end of the switch circuit is connected to the first end of the phase shift sub-circuit, and the second end of the switch circuit is connected to the second end of the phase shift sub-circuit.

[0011] In the above technical solution, by enabling different phase shifting units in different power intervals, the phase difference can be changed stepwise with the change of the power of the input signal, thereby optimizing the power points in the interval from the power critical point to the power saturation point.

[0012] In a feasible implementation manner of the first aspect, the phase shift subcircuit includes a microstrip line, a lumped capacitor, or a lumped inductor.

[0013] In a feasible implementation manner of the first aspect, the first power is a first value, the second power is a second value, and the first value and the second value are different.

[0014] In a feasible implementation of the first aspect, the first phase shift circuit includes a first coupler, a first varactor capacitor and a second varactor capacitor, the first end of the first coupler is connected to the input end of the phase shift network, the second end of the first coupler is connected to the output end of the phase shift network, the third end of the first coupler is connected to the first end of the first varactor capacitor, the fourth end of the first coupler is connected to the first end of the second varactor capacitor, the second ends of the first varactor capacitor and the second varactor capacitor are connected to the ground end, and the controlled ends of the first varactor capacitor and the second varactor capacitor are connected to the controlled end of the first phase shift circuit.

[0015] In the above technical solution, by dynamically adjusting the capacitance of the capacitor through the control signal, the phase difference provided by the phase shift circuit can continuously change with the power change of the input signal, thereby optimizing all power points in the range from the power critical point to the power saturation point.

[0016] In a possible implementation of the first aspect, the varactor capacitor includes a varactor diode.

[0017] In a feasible implementation of the first aspect, the first phase-shifting circuit includes a second coupler, a first fixed-capacitance capacitor, a second fixed-capacitance capacitor and a transistor, the first end of the second coupler is connected to the input end of the phase-shifting network, the second end of the second coupler is connected to the output end of the phase-shifting network, the third and fourth ends of the second coupler are connected to the first end of the fixed-capacitance capacitor, the second end of the fixed-capacitance capacitor is connected to the first and second ends of the transistor, and the controlled end of the transistor is connected to the controlled end of the first phase-shifting circuit.

[0018] In a feasible implementation of the first aspect, the phase shift network also includes a second phase shift circuit, which is used to adjust the phase difference between the output signal of the first power amplifier branch and the output signal of the second power amplifier branch according to a control signal, the power amplifier circuit inputs an input signal of the first power, and the phase difference is a third phase difference, the power amplifier circuit inputs an input signal of the second power, and the phase difference is a fourth phase difference, and the third phase difference is the same as the fourth phase difference.

[0019] In a feasible implementation manner of the first aspect, the first power amplifier branch is a control signal power amplifier branch, the second power amplifier branch is a main power amplifier branch, and the phase shift network is arranged between the amplifier and the power divider.

[0020] In a feasible implementation manner of the first aspect, the first power amplifier branch is a main power amplifier branch, the second power amplifier branch is a control signal power amplifier branch, and the phase shift network is arranged between the third coupler and the power divider.

[0021] In a feasible implementation manner of the first aspect, the second power amplifier branch includes a fixed phase shift circuit.

[0022] In a second aspect, the present application provides a radio frequency front-end component, including a power amplifier circuit and a low-noise amplifier circuit, wherein the power amplifier circuit is coupled to the low-noise amplifier circuit, wherein the power amplifier circuit is the power amplifier circuit of the aforementioned first aspect.

[0023] In a third aspect, the present application provides a radio frequency transceiver system, including an antenna and a radio frequency front-end component, the antenna and the radio frequency front-end component are coupled, and the radio frequency front-end component includes the radio frequency front-end component of the second aspect mentioned above.

[0024] In a fourth aspect, the present application provides an electronic device, comprising: a power supply and a radio frequency transceiver system, the power supply is used to supply power to the radio frequency transceiver system, and the radio frequency transceiver system includes the radio frequency transceiver system of the third aspect mentioned above.

[0025] The technical effects of the second to fourth aspects refer to the technical effects of the first aspect and any of its embodiments, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application;

[0027] Figure 2 A power-operating efficiency matching curve diagram of a power amplifier provided in an embodiment of the present application;

[0028] Figure 3 A schematic diagram of the structure of a power amplifier provided in an embodiment of the present application;

[0029] Figure 4 Another structural schematic diagram of a power amplifier provided in an embodiment of the present application;

[0030] Figure 5 Another structural schematic diagram of a power amplifier provided in an embodiment of the present application;

[0031] Figure 6 Another structural schematic diagram of a power amplifier provided in an embodiment of the present application;

[0032] Figure 7 Another structural schematic diagram of a power amplifier provided in an embodiment of the present application;

[0033] Figure 8 Another structural schematic diagram of a power amplifier provided in an embodiment of the present application;

[0034] Fig. 9 A phase change schematic diagram provided for an embodiment of the present application;

[0035] Fig.10 A schematic diagram of insertion loss variation provided in an embodiment of the present application;

[0036] Fig.11 A power-operating efficiency matching curve diagram of another power amplifier provided in an embodiment of the present application;

[0037] Fig.12 Another structural schematic diagram of a power amplifier provided in an embodiment of the present application;

[0038] Fig.13A power-operating efficiency matching curve diagram of another power amplifier provided in an embodiment of the present application;

[0039] Fig.14 Another structural schematic diagram of a power amplifier provided in an embodiment of the present application;

[0040] Fig.15 Another schematic diagram of the structure of a power amplifier provided in an embodiment of the present application.

[0041] Figure numerals: 110, radio frequency circuit; 120, memory; 130, input device; 140, display module; 150, sensor; 160, audio circuit; 170, camera module; 180, system chip; 41, input end; 42, power divider; 43, first power amplifier branch; 44, second power amplifier branch; 45, output end; 431, phase shift network; 432, first power amplifier; 441, first coupler; 442, second power amplifier; 443, third power amplifier; 444, third Two couplers; 445, fixed phase shift circuit; 4311, first phase shift circuit; 4312, conversion circuit; 4313, second phase shift circuit; 43111, third coupler; 43112, first variable capacitance capacitor; 43113, second variable capacitance capacitor; 43114, fourth coupler; 43115, first fixed capacitance capacitor; 43116, second fixed capacitance capacitor; 43117, transistor; 43118, phase shift sub-circuit; 43119, switch circuit; 43121, comparison circuit. DETAILED DESCRIPTION

[0042] 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. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0043] In the following, the terms "first", "second", etc. are used only for convenience of description and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more. For example, a plurality of processing units refers to two or more processing units.

[0044] In addition, in the embodiments of the present application, "upper", "lower", "left" and "right" are not limited to being defined relative to the orientation of the components schematically placed in the drawings. It should be understood that these directional terms can be relative concepts, which are used for description and clarification relative to the components, and can change accordingly according to the change in the orientation of the components placed in the drawings. In the drawings, for the sake of clarity, the thickness of the layers and regions is exaggerated, and the size ratio relationship between the parts in the drawings does not reflect the actual size ratio relationship.

[0045] In the embodiments of the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. In addition, the term "electrical connection" can be a direct electrical connection or an indirect electrical connection through an intermediate medium.

[0046] In the embodiments of the present application, the term "module" is generally a functional structure divided according to logic, and the "module" can be implemented by pure hardware, or by a combination of software and hardware. In the embodiments of the present application, "and / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, B exists alone, and A and B exist at the same time.

[0047] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0048] The solution provided in the embodiments of the present application can be applied to an electronic device having one or more integrated circuits, and the electronic device can be a network device or a terminal device. The network equipment includes but is not limited to: evolved NodeB (eNB), radio network controller (RNC), Node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (for example, home evolved NodeB, or home Node B, HNB), baseband unit (BBU), access point (AP) in wireless fidelity (WIFI) system, wireless relay node, wireless backhaul node, transmission point (TRP or transmission point, TP), etc., and can also be 5G, such as gNB in ​​new radio (NR) system, or transmission point (TRP or TP), one or a group of (including multiple antenna panels) antenna panels of a base station in a 5G system, or it can also be a network node constituting a gNB or a transmission point, such as a baseband unit or a distributed unit (DU), etc.

[0049] The terminal device may also be referred to as a user device, an access terminal, a user unit, a user station, a mobile station, a mobile station, a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a wireless communication device, a user agent or a user device. The terminal device in the embodiments of the present application may be a mobile phone, a tablet computer, a computer, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a terminal device in industrial control, a terminal device in self-driving, a terminal device in remote medical, a terminal device in a smart home, etc.

[0050] Taking a mobile phone as an example, Figure 1This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include: a radio frequency (RF) circuit 110, a memory 120, an input device 130, a display module 140, a sensor 150, an audio circuit 160, a camera module 170, and a system on chip (SOC) 180. Figure 1 The following is a detailed introduction to the various components of the electronic device:

[0051] Audio circuitry 160 , speakers, and microphones may provide an audio interface between a user and the electronic device.

[0052] The RF circuit 110 can be used to send and receive information, or receive or send signals during a call. In particular, after receiving the downlink information of the base station, it is sent to the SOC 180 for processing; in addition, the uplink data is sent to the base station. Generally, the RF circuit 110 includes but is not limited to an antenna, at least one power amplifier circuit, a transceiver, a coupler, a low noise amplifier (LNA), a duplexer, etc. In addition, the RF circuit 110 can also communicate with the network and other devices through wireless communication.

[0053] The electronic device may also include a power source, such as a battery, for supplying power to each component. The power source may be logically connected to the processor through a power management system, so that the power management system can manage charging, discharging, power consumption, and other functions.

[0054] Although not shown, the electronic device may also include a wireless fidelity (WiFi) module, a Bluetooth module, etc., which will not be described in detail in the present embodiment. Those skilled in the art will understand that Figure 1 The electronic device structure shown in the figure does not constitute a limitation of the electronic device, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0055] The RF circuit 110 may include but is not limited to an antenna, at least one filter, a switch, a power amplifier, a low noise amplifier (LNA), etc. The RF circuit 110 may receive electromagnetic waves from the antenna, filter, amplify, etc. the received electromagnetic waves, and transmit them to a modulation and demodulation processor for demodulation.

[0056] Modern wireless communication systems usually use modulation signals with a high peak to average power ratio (PAPR) to improve the utilization rate of scarce spectrum resources. This makes more efficient use of spectrum, improves data transmission rate, and meets the growing communication needs. However, in actual applications, in most business scenarios, the business load of terminal equipment is not high, resulting in the power amplifier often being in a power back-off state far higher than the signal peak to average power ratio. In this state, the working efficiency of the power amplifier is relatively low, resulting in a large operating power consumption of the entire RF circuit.

[0057] For example, see Figure 2 , Figure 2 The dotted curve in the figure is the theoretical working efficiency curve of the traditional Class B power amplifier. It can be seen that when the power back-off amount of the power amplifier continues to increase, the working efficiency of the power amplifier gradually decreases. The power back-off amount refers to the difference between the current power of the power amplifier and the maximum power of the power amplifier. Therefore, when the power amplifier is in the power back-off state, the working efficiency of the power amplifier is low. For high peak-to-average ratio signals, when the power back-off amount is large, only a small amount of DC energy of the power amplifier is converted into RF energy, and the rest of the energy is almost converted into heat. Therefore, it is necessary to optimize the working efficiency and performance of the power amplifier.

[0058] In a possible implementation of the related technology, a load-modulated balanced power amplifier circuit can be used to improve the working efficiency of the power amplifier in the power fallback state. The load-modulated balanced power amplifier circuit includes a main power amplifier branch and a control signal power amplifier branch. By adjusting the phase and amplitude of the control signal power amplifier branch, the output impedance of the load-modulated balanced power amplifier circuit is adjusted to achieve load impedance matching and improve working efficiency.

[0059] For example, see Figure 3The circuit diagram of the load-modulated balanced power amplifier circuit shown in the figure comprises a main power amplifier branch and a control signal power amplifier branch, the main power amplifier branch and the control signal power amplifier branch are connected to the input end through a power divider, the main power amplifier branch comprises a power amplifier PA1, a power amplifier PA2, a coupler 1 and a coupler 2, the input end of the main power amplifier branch is connected to the input end of the coupler 1, the first output end of the coupler 1 is connected to the input end of the power amplifier PA1, the second output end of the coupler 1 is connected to the input end of the power amplifier PA2, the output end of the power amplifier PA1 is connected to the first input end of the coupler 2, the output end of the power amplifier PA2 is connected to the second input end of the coupler 2, and the output end of the coupler 2 is connected to the output end of the main power amplifier branch. The control signal power amplifier branch includes a power amplifier PA3 and a phase shift network, the input end of the phase shift network is connected to the input end of the control signal power amplifier branch, the output end of the phase shift network is connected to the input end of the power amplifier PA3, the output end of the power amplifier PA3 is connected to the output end of the control signal power amplifier branch, and the output end of the control signal power amplifier branch is connected to the isolation end (isolator, ISO) of the coupler 2.

[0060] When the load modulation balanced power amplifier circuit is running, the control signal power amplifier branch is configured as a class B or C static working mode, and the main power amplifier branch is configured as a class AB static working mode. When the power of the input signal is small, the input power is insufficient to drive the power amplifier PA3, so the isolation port of the coupler 2 is in an open circuit state. At this time, the power amplifiers PA1 and PA2 of the main power amplifier branch are already in the on state, but the output power is low.

[0061] As the input signal power gradually increases, the control signal amplifier branch will reach the critical state of being turned on, and the load modulation balanced amplifier is at the maximum power back-off point. At this stage, the output impedance of the main amplifier branch is relatively large. To ensure its maximum working efficiency, the isolation port of coupler 2 remains open. When the control signal amplifier branch is turned on, the power entering the isolation port of coupler 2 is superimposed on the output power of the main amplifier, and the output power of the overall amplifier continues to increase.

[0062] As the input signal power increases further, the main power amplifier branch and the control signal power amplifier branch enter the saturation state at the same time, and the overall output power of the load modulation balanced power amplifier circuit also reaches a peak value. At this time, the power amplitude and phase of the control signal power amplifier branch entering the isolation port of coupler 2 will affect the output impedance of the main power amplifier branch, thereby generating load modulation, so that the main power amplifier branch can obtain the best load traction and achieve maximum working efficiency in a certain state.

[0063] Continue reading Figure 2 , Figure 2The solid line curve in is the theoretical working efficiency curve of the load modulation balanced power amplifier circuit. It can be seen that the load modulation balanced power amplifier circuit has two working efficiency peak points. As an example, the two working efficiency peak points can be the peak power point (power saturation point B) and the peak power point back-off -10dB (power critical point A). Compared with the traditional Class B power amplifier, the load modulation balanced power amplifier circuit has a significant improvement in working efficiency in the range from power critical point A to power saturation point B.

[0064] For the phase-shifting network set on the control signal power amplifier branch, its design phase is to ensure that the main power amplifier branch obtains the best load impedance in the saturation state. However, in the process from the control signal power amplifier branch turning on to reaching the saturation state, the optimal phase required by the main power amplifier branch at different power points is not fixed, but changes with the power. If the phase design of the phase-shifting network is fixed, it cannot adapt to this change, resulting in the main power amplifier branch not having the best working efficiency at different back-off powers.

[0065] In order to solve the above problems, the present application embodiment provides a power amplifier circuit. Figure 4 The power amplifier circuit includes an input terminal 41, a power divider 42, a first power amplifier branch 43, a second power amplifier branch 44 and an output terminal 45. The input terminal of the power divider 42 is connected to the input terminal 41 of the power amplifier circuit, the input terminals of the first power amplifier branch 43 and the second power amplifier branch 44 are connected to the output terminal of the power divider 42, the output terminals of the first power amplifier branch 43 and the second power amplifier branch 44 are coupled to the output terminal 45 of the power amplifier circuit, and a phase shift network 431 is arranged on the first power amplifier branch 43. When the power amplifier circuit is working, the phase shift network 431 is used to dynamically adjust the phase difference between the output signal of the first power amplifier branch 43 and the output signal of the second power amplifier branch 44 according to the power of the input signal of the power amplifier circuit. A control signal is output to the phase shift network 431 through the power divider 42, and the phase difference between the output signal of the first power amplifier branch 43 and the output signal of the second power amplifier branch 44 is dynamically adjusted through the control signal.

[0066] As an example, when the power of the input signal of the power amplifier circuit is P1, the phase difference between the output signal of the first power amplifier branch 43 and the output signal of the second power amplifier branch is φ1. When the power of the input signal of the power amplifier circuit is P2, the phase difference between the output signal of the first power amplifier branch 43 and the output signal of the second power amplifier branch is φ2. P1 is different from P2, and the phase difference φ1 is also different from the phase difference φ2.

[0067] It should be noted that when the first power amplifier branch 43 is the main power amplifier branch, the second power amplifier branch 44 is the control signal power amplifier branch, and when the first power amplifier branch 43 is the control signal power amplifier branch, the second power amplifier branch 44 is the main power amplifier branch. The phase shift network can be set on the main power amplifier branch or on the control signal power amplifier branch.

[0068] The specific setting position of the phase shift network 431 can be determined by multiple adjustment factors. For example, the specific setting position of the phase shift network 431 can be determined based on the corresponding relationship between the change trend of the phase adjustment value of the phase shift network 431 and the change trend of the input signal power, and the corresponding relationship between the change trend of the phase adjustment value of the phase shift network 431 and the change trend of the control signal.

[0069] As an example, the control signal can be a voltage control signal. When the phase adjustment value of the phase shift network 431 increases with the increase of the input signal power, and the phase adjustment value of the phase shift network 431 increases with the increase of the voltage control signal, the phase shift network 431 can be set on the control signal power amplifier branch.

[0070] When the phase adjustment value of the phase shift network 431 increases with the increase of the input signal power, and the phase adjustment value of the phase shift network 431 decreases with the increase of the voltage control signal, the phase shift network 431 can be set on the main power amplifier branch.

[0071] When the phase adjustment value of the phase shift network 431 decreases with the increase of the input signal power, and the phase adjustment value of the phase shift network 431 increases with the increase of the voltage control signal, the phase shift network 431 can be set on the main power amplifier branch.

[0072] When the phase adjustment value of the phase shift network 431 decreases with the increase of the input signal power, and the phase adjustment value of the phase shift network 431 decreases with the increase of the voltage control signal, the phase shift network 431 can be set on the control signal power amplifier branch.

[0073] When the first power amplifier branch 43 is a control signal power amplifier branch and the second power amplifier branch 44 is a main power amplifier branch, the phase shift network 431 is arranged on the first power amplifier branch 43. Figure 5The first power amplifier branch 43 may include a phase shift network 431 and a first power amplifier 432, the input end of the phase shift network 431 is connected to the input end of the control signal power amplifier branch, the output end of the phase shift network 431 is connected to the input end of the first power amplifier 432, and the output end of the first power amplifier 432 is connected to the output end of the control signal power amplifier branch. The main power amplifier branch may include a first coupler 441, a second power amplifier 442, a third power amplifier 443, and a second coupler 444, the input end of the second power amplifier branch 44 is connected to the input end of the first coupler 441, the first output end of the first coupler 441 is connected to the input end of the second power amplifier 442, the second output end of the first coupler 441 is connected to the input end of the third power amplifier 443, the output end of the second power amplifier 442 is connected to the first input end of the second coupler 444, the output end of the third power amplifier 443 is connected to the second input end of the second coupler 444, and the output end of the second coupler 444 is connected to the output end of the second power amplifier branch 44. The first coupler 441 and the second coupler 444 may be 3 dB couplers.

[0074] The phase shift network 431 can dynamically adjust the phase difference between the output signal of the first power amplifier branch 43 and the output signal of the second power amplifier branch 44 according to the input signal of the power amplifier circuit, that is, the phase adjustment value provided by the phase shift network 431 changes dynamically, so the main power amplifier branch of the power amplifier circuit has a corresponding phase difference from the power critical point to the power saturation point. Compared with the fixed phase difference, the load impedance of the main power amplifier branch of the power amplifier circuit can be optimized, thereby improving the overall working efficiency of the power amplifier circuit between the power critical point and the power saturation point.

[0075] According to the size of the variation range of the phase shift angle, the phase shift network 431 can be implemented in a variety of ways. When the variation range of the phase shift angle is small, the phase shift network 431 may include a first phase shift circuit, and the first phase shift circuit is used to provide a variable phase difference. When the variation range of the phase shift angle is large, the phase shift network 431 may include a first phase shift circuit and a second phase shift circuit, and the second phase shift circuit is used to provide a fixed phase difference. As an example, when the control signal power amplifier path is just turned on, a phase shift angle of 100° is required, and a phase shift angle of 150° is required when saturation is reached, then the first phase shift circuit can produce a phase variation range of 50°. If the variation range of the first phase shift circuit is 100°~150°, the second phase shift circuit is not required, and if the variation range of the first phase shift circuit is 0°~50°, the second phase shift circuit is required to provide a fixed phase shift angle of 100°. It should be noted that the specific manner in which the first phase shift circuit and the second phase shift circuit are set in the phase shift network 431 can be adjusted according to actual needs, and the embodiments of the present application are not limited to this.

[0076] When the phase shift network 431 includes a first phase shift circuit, refer to Figure 6 The phase shift network 431 may include a first phase shift circuit 4311 and a conversion circuit 4312, wherein the input end of the conversion circuit 4312 is connected to the power divider 42, and the output end of the conversion circuit 4312 is connected to the controlled end of the first phase shift circuit 4311, and the conversion circuit 4312 is used to provide a variable control signal to the first phase shift circuit 4311 according to the control signal input by the power divider.

[0077] As an example, the conversion circuit 4312 can convert a power signal output by the power divider into a DC voltage signal, and then control the phase change of the first phase shift circuit 4311 through the DC voltage signal. The control signal changes with the power change of the input signal of the power amplifier circuit, so that the first phase shift circuit 4311 can dynamically adjust the phase difference between the first power amplifier branch 43 and the second power amplifier branch 44.

[0078] There are multiple implementation methods for the first phase shift circuit 4311 to dynamically adjust the phase difference between the output signal of the first power amplifier branch 43 and the output signal of the second power amplifier branch 44. One adjustment method may be to allow the phase difference to change continuously with the change of the power of the input signal, and another adjustment method may be to allow the phase difference to change in steps with the change of the power of the input signal.

[0079] When the phase difference changes continuously with the power of the input signal, all power points within the range from the power critical point to the power saturation point can be optimized. In a feasible implementation, the first phase shift circuit 4311 can be a continuous phase shift circuit, which can allow the power amplifier circuit to have a corresponding phase difference for each power point from the power critical point to the power saturation point.

[0080] When the control signal output by the conversion circuit 4312 controls the first phase shift circuit 4311 to provide a continuously changing phase adjustment value, this can be achieved by controlling the capacitance change of the capacitor in the first phase shift circuit 4311. One implementation method may be to allow the capacitance of the capacitor itself to change with the change of the control signal, and another implementation method may be to allow the capacitance of the capacitor itself to be fixed, and to achieve the characteristic of controlling the capacitance change by the control signal through other electronic devices.

[0081] When the capacitance of the capacitor itself changes, and the capacitance of the first phase shift circuit 4311 changes with the change of the control signal, refer to Figure 7In the power amplifier circuit shown, the first phase shift circuit 4311 may include a third coupler 43111, a first varactor capacitor 43112 and a second varactor capacitor 43113, the first end of the third coupler 43111 is connected to the input end of the phase shift network 431, the second end of the third coupler 43111 is connected to the output end of the phase shift network 431, the third end of the third coupler 43111 is connected to the first end of the first varactor capacitor 43112, the fourth end of the third coupler 43111 is connected to the first end of the second varactor capacitor 43113, the second ends of the first varactor capacitor 43112 and the second varactor capacitor 43113 are connected to the ground, and the controlled ends of the first varactor capacitor 43112 and the second varactor capacitor 43113 are connected to the controlled end of the first phase shift circuit 4311.

[0082] In a feasible implementation, the first varactor capacitor 43112 and the second varactor capacitor 43113 may be varactor diodes, and the control signal is a voltage control signal. When the voltage control signal applied to the varactor diode is different, the PN junction width of the varactor diode changes, thereby changing the capacitance value of the varactor diode. For example, as the voltage control signal increases, the capacitance value of the varactor diode decreases, and as the voltage control signal decreases, the capacitance value of the varactor diode increases.

[0083] When the capacitance of the capacitor itself remains unchanged and the capacitance of the first phase shift circuit 4311 changes with the change of the control signal, refer to Figure 8 In the power amplifier circuit shown, the first phase shift circuit 4311 may include a fourth coupler 43114, a first fixed-capacitance capacitor 43115, a second fixed-capacitance capacitor 43116 and a transistor 43117, the first end of the fourth coupler 43114 is connected to the input end of the phase shift network 431, the second end of the fourth coupler 43114 is connected to the output end of the phase shift network 431, the third end of the fourth coupler 43114 is connected to the first end of the first fixed-capacitance capacitor 43115, the fourth end of the fourth coupler 43114 is connected to the first end of the second fixed-capacitance capacitor 43116, the second ends of the first fixed-capacitance capacitor 43115 and the second fixed-capacitance capacitor 43116 are connected to the transistor 43117, and the controlled end of the transistor 43117 is connected to the controlled end of the first phase shift circuit 4311.

[0084] Transistor 43117 can be a triode, a field effect transistor or a high electron mobility transistor. As an example, when transistor 43117 is a field effect transistor and is in a cut-off state, the voltage change at the output terminal will cause the electric field between the gate and the source (drain) to change, thereby affecting the input capacitance of the transistor. Since the capacitance value is related to the electric field strength, as the voltage changes, the capacitance value will be adjusted accordingly, showing the characteristics of voltage-controlled capacitance.

[0085] In the above embodiment, in order to ensure that the influence on the signal amplitude is reduced during the phase adjustment process, the third coupler 43111 or the fourth coupler 43114 in the first phase shift circuit 4311 can adopt a 3dB coupler. The use of a 3dB coupler can make the phase of the signal input to the first phase shift circuit 4311 change when the capacitance of the first phase shift circuit 4311 is dynamically adjusted, but the insertion loss remains almost unchanged. As an example, refer to Fig. 9 The phase change diagram and Fig.10 The insertion loss variation diagram shown in Fig. 9 When the capacitance changes, the phase difference between the two ends of the first phase shift circuit 4311 changes from a solid line to a dotted line. Fig.10 , the insertion loss at both ends of the first phase shift circuit 4311 changes from a solid line to a dotted line, but the size remains almost unchanged.

[0086] See also Fig.11 , the solid line portion is a theoretical working efficiency curve of a power amplifier with a fixed phase adjustment value provided by the phase shift network 431, and the dotted line portion is a theoretical working efficiency curve of the power amplifier of the present application. As an example, within the range from the power critical point A to the power saturation point B, the overall working efficiency of the power amplifier can be improved.

[0087] When the phase difference changes in steps with the power of the input signal, the power points in the range from the power critical point to the power saturation point can be optimized. In a feasible implementation, the first phase shift circuit 4311 can be a discrete phase shift circuit, which can allow each individual power point from the power critical point to the power saturation point to have a corresponding phase difference.

[0088] In a feasible implementation, the first phase shift circuit 4311 may include N phase shift units, which are connected in series between the input and output of the first phase shift circuit 4311, the input of the first phase shift unit is connected to the input of the first phase shift circuit 4311, the output of the first phase shift unit is connected to the input of the second phase shift circuit, the output of the N-1th phase shift unit is connected to the input of the Nth phase shift circuit, and the output of the Nth phase shift unit is connected to the output of the first phase shift circuit 4311. Each phase shift unit is used to provide a fixed phase change value.

[0089] It should be noted that the phase change value provided by each phase shift unit may be the same, for example, the phase change value provided by each phase shift unit may be 10°. The phase change value provided by each phase shift unit may also be different, the first phase shift unit provides a phase change value of 10°, and the second phase shift unit provides a phase change value of 15°; or the first phase shift unit provides a phase change value of 15°, and the second phase shift unit provides a phase change value of 10°. The phase change value provided by each phase shift unit may also be negative, for example, the phase change value provided by each phase shift unit may be -10°.

[0090] The phase shift units can be turned on one by one, and the number of phase shift units can match the number of power points to be adjusted. When the number of power points to be adjusted is 4, 4 phase shift units can be set in the discrete phase shift circuit. The more phase shift units there are, the closer the phase modulation effect of the discrete phase shift circuit is to that of the continuous phase shift circuit.

[0091] See also Fig.12 The circuit diagram of the load-modulated balanced power amplifier circuit shown in the figure, each phase shift unit may include a phase shift sub-circuit 43118, a switch circuit 43119 and a comparison circuit 43121, the first input end of the comparison circuit 43121 is connected to the controlled end of the first phase shift circuit 4311, the second input end of the comparison circuit 43121 is connected to the reference voltage input end, the output end of the comparison circuit 43121 is connected to the controlled end of the switch circuit 43119, the first end of the switch circuit 43119 is connected to the first end of the phase shift sub-circuit 43118, and the second end of the switch circuit 43119 is connected to the second end of the phase shift sub-circuit 43118.

[0092] The comparison circuit 43121 can output a corresponding level control signal by comparing the relationship between the signals inputted at the first input terminal and the second input terminal. For example, when the voltage signal V1 is inputted at the first input terminal of the comparison circuit 43121, the voltage signal V2 is inputted at the second input terminal, and V1 is greater than V2, the comparison circuit 43121 can output a low level.

[0093] The switch circuit 43119 may include a through line and a switch device, and the switch device adjusts the on / off state of the through line according to the level control signal output by the comparison circuit 43121. For example, when the switch circuit 43119 receives the high level control signal output by the comparison circuit 43121, the switch circuit 43119 is in the on state, and when the switch circuit 43119 receives the low level control signal output by the comparison circuit 43121, the switch circuit 43119 is in the off state. In order to ensure that the signal amplitude of the switch circuit 43119 does not change significantly before and after the switch circuit 43119 is turned on and off, a resistor may be connected in series in the switch circuit 43119 to match the insertion loss formed by the phase shift subcircuit 43118 through the resistor. The access state of the phase shift subcircuit 43118 may be determined according to the on / off state of the switch circuit 43119. For example, when the switch circuit 43119 is in the on state, the phase shift subcircuit 43118 is in the off state, and when the switch circuit 43119 is in the off state, the phase shift subcircuit 43118 is in the access state.

[0094] See also Fig.13 , in the interval from the power critical point A to the power saturation point B, the solid line portion is the theoretical working efficiency curve of the power amplifier with a fixed phase adjustment value provided by the phase shift network, and the dotted line portion is the theoretical working efficiency curve of the power amplifier of the present application. It can be seen that in the interval from the power critical point A to the power saturation point B, the power amplifier of the present application can optimize the working efficiency of the power amplifier at certain power points, for example, optimizing the working efficiency of the power amplifier at power point C and power point D.

[0095] As an example, the above implementation process is described below. When the number of phase shift units is 3, they include a phase shift unit numbered 1, a phase shift unit numbered 2, and a phase shift unit numbered 3. Each phase shift unit provides a phase change of 10°, and the reference voltage signal input to the phase shift unit gradually increases, that is, the reference voltage signal input to the phase shift unit numbered 1 is smaller than the reference voltage signal input to the phase shift unit numbered 2, and the reference voltage signal input to the phase shift unit numbered 2 is smaller than the reference voltage signal input to the phase shift unit numbered 3.

[0096] When the power of the input signal is the power corresponding to the power critical point (corresponding to power point A), the voltage control signal input to the comparison circuit 43121 of all phase shift units is less than the reference voltage signal input to the reference voltage input terminal, so the switch circuit 43119 of all phase shift units is in the on state, and the phase shift sub-circuit 43118 of all phase shift units is not in effect. When the power of the input signal gradually increases and reaches the power corresponding to the power point C, the voltage control signal input to the comparison circuit 43121 of the phase shift unit numbered 1 is greater than the reference voltage signal input to the reference voltage input terminal, the switch circuit 43119 of the phase shift unit numbered 1 is in the off state, and the phase shift unit numbered 1 is in effect, generating a 10° phase change, thereby improving the working efficiency of the power amplifier at the power point C. When the power of the input signal continues to increase and reaches the power corresponding to the power point D, the voltage control signal of the comparison circuit 43121 of the phase shift unit numbered 1 and 2 is greater than the reference voltage signal input to the reference voltage input terminal, the switch circuit 43119 of the phase shift unit numbered 1 and 2 is in the disconnected state, and the phase shift units numbered 1 and 2 function, resulting in a total phase change of 20°, thereby improving the working efficiency of the power amplifier at the power point D. When the power of the input signal continues to increase and reaches the power corresponding to the power saturation point (corresponding to the power point B), the voltage control signal of the comparison circuit 43121 of all the phase shift units is greater than the reference voltage signal input to the reference voltage input terminal, the switch circuit 43119 of all the phase shift units is in the disconnected state, and all the phase shift units function, resulting in a total phase change of 30°, thereby improving the working efficiency of the power amplifier at the power point B.

[0097] In a feasible implementation, the phase shift subcircuit 43118 can be implemented by any one of microstrip lines, lumped capacitors or lumped inductors. Microstrip lines are a commonly used transmission line structure that can effectively control the phase of signal propagation. By adjusting the length and width of the microstrip line, a specific phase shift can be achieved. Lumped capacitors and lumped inductors can adjust the phase of the signal by configuring in parallel or in series. For example, lumped capacitors introduce phase delays in the signal, while lumped inductors produce phase advances. According to the frequency response characteristics of the circuit, suitable components can be selected to implement the function of the phase shift subcircuit 43118 and achieve the desired phase adjustment effect.

[0098] When the phase shift network 431 includes a first phase shift circuit 4311 and a second phase shift circuit, refer to Fig.14The phase shift network 431 may include a first phase shift circuit 4311, a conversion circuit 4312, and a second phase shift circuit 4313. The input end of the conversion circuit 4312 is connected to the power divider 42, the output end of the conversion circuit 4312 is connected to the controlled end of the first phase shift circuit 4311, the input end of the second phase shift circuit 4313 is connected to the power divider 42, and the output end of the second phase shift circuit 4313 is connected to the input end of the first phase shift circuit 4311. The first phase shift circuit 4311 is used to provide a variable phase difference, and the second phase shift circuit 4313 is used to provide a fixed phase difference. The flexible combination of the first phase shift circuit 4311 and the second phase shift circuit 4313 can improve the design freedom of the entire phase shift network 431.

[0099] As an example, when the phase change is only provided by the second phase shift circuit 4313, when the power of the input signal of the power amplifier circuit is P3, the phase difference between the output signal of the first power amplifier branch 43 and the output signal of the second power amplifier branch is φ3, and when the power of the input signal of the power amplifier circuit is P4, the phase difference between the output signal of the first power amplifier branch 43 and the output signal of the second power amplifier branch is φ4, P3 is different from P4, and the phase difference φ3 is the same as the phase difference φ4.

[0100] When the first power amplifier branch 43 is the main power amplifier branch and the second power amplifier branch 44 is the control signal power amplifier branch, the phase shift network 431 is set in the first power amplifier branch 43. Its specific implementation method can be exactly the same as when the first power amplifier branch 43 is the control signal power amplifier branch and the second power amplifier branch 44 is the main power amplifier branch, so this application will not repeat it. Fig.15 When the phase shift network 431 is arranged in the first power amplifier branch 43, the first power amplifier branch 43 includes the phase shift network 431, the first coupler, the first power amplifier, the second power amplifier and the second coupler, and the phase shift network 431 is arranged between the first coupler and the power divider 42. The second power amplifier branch 44 includes a third power amplifier, and a fixed phase shift circuit 445 may also be arranged on the second power amplifier branch 44.

[0101] The present application also provides a radio frequency front-end component, including a power amplifier circuit and a low-noise amplifier circuit, wherein the power amplifier circuit is coupled to the low-noise amplifier circuit, wherein the power amplifier circuit is any of the aforementioned power amplifier circuits.

[0102] The present application also provides a radio frequency transceiver system, including an antenna and a radio frequency front-end component, the antenna and the radio frequency front-end component are coupled, and the radio frequency front-end component includes the aforementioned radio frequency front-end component.

[0103] The present application also provides an electronic device, comprising: a power supply and a radio frequency transceiver system, the power supply is used to supply power to the radio frequency transceiver system, and the radio frequency transceiver system includes the aforementioned radio frequency transceiver system.

[0104] Those of ordinary skill in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0105] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A power amplifier circuit, characterized in that: The power amplifier circuit is a load-modulated balanced power amplifier circuit, comprising: Power divider; A first power amplifier branch, wherein an input end of the first power amplifier branch is connected to the power divider, and the first power amplifier branch comprises a phase shift network, and the phase shift network is connected to an input end of the first power amplifier branch; a second power amplifier branch, wherein an input end of the second power amplifier branch is connected to the power divider; Wherein, the phase shift network is used to adjust the phase difference between the output signal of the first power amplifier branch and the output signal of the second power amplifier branch according to the input signal of the power amplifier circuit; the power amplifier circuit inputs the input signal of the first power, and the phase difference is the first phase difference; the power amplifier circuit inputs the input signal of the second power, and the phase difference is the second phase difference; the first phase difference and the second phase difference are different; The phase shift network includes a first phase shift circuit and a second phase shift circuit, wherein the first phase shift circuit is used to provide a variable phase difference, and the second phase shift circuit is used to provide a fixed phase difference.

2. The power amplifier circuit according to claim 1, characterized in that: The phase shift network further includes a conversion circuit; an input end of the conversion circuit is connected to the power divider, and an output end of the conversion circuit is connected to a controlled end of the first phase shift circuit; The conversion circuit is used to provide a control signal to the first phase shift circuit according to the power of the input signal; The first phase shift circuit is used to adjust the phase difference between the first power amplifier branch output signal and the second power amplifier branch output signal according to the control signal.

3. The power amplifier circuit according to claim 2, characterized in that: The first power is a first interval value, the second power is a second interval value, and the first interval value and the second interval value are different.

4. The power amplifier circuit according to claim 3, characterized in that: The first phase shift circuit comprises a plurality of phase shift units, the plurality of phase shift units are connected in series between an input end and an output end of the first phase shift circuit, and each of the phase shift units comprises a phase shift subcircuit, a switch circuit and a comparison circuit; The first input end of the comparison circuit is connected to the controlled end of the first phase shift circuit, the second input end of the comparison circuit is connected to the reference voltage input end, the output end of the comparison circuit is connected to the controlled end of the switch circuit, the first end of the switch circuit is connected to the first end of the phase shift sub-circuit, and the second end of the switch circuit is connected to the second end of the phase shift sub-circuit.

5. The power amplifier circuit according to claim 4, characterized in that: The phase shift subcircuit includes a microstrip line, a lumped capacitor or a lumped inductor.

6. The power amplifier circuit according to claim 2, characterized in that: The first power is a first value, the second power is a second value, and the first value and the second value are different.

7. The power amplifier circuit according to claim 6, characterized in that: The first phase shift circuit includes a first coupler, a first varactor capacitor and a second varactor capacitor, wherein a first end of the first coupler is connected to an input end of the phase shift network, a second end of the first coupler is connected to an output end of the phase shift network, a third end of the first coupler is connected to a first end of the first varactor capacitor, a fourth end of the first coupler is connected to a first end of the second varactor capacitor, second ends of the first varactor capacitor and the second varactor capacitor are connected to a ground end, and controlled ends of the first varactor capacitor and the second varactor capacitor are connected to a controlled end of the first phase shift circuit.

8. The power amplifier circuit according to claim 7, characterized in that: The varactor capacitor includes a varactor diode.

9. The power amplifier circuit according to claim 6, characterized in that: The first phase-shifting circuit includes a second coupler, a first fixed-capacitance capacitor, a second fixed-capacitance capacitor and a transistor, wherein the first end of the second coupler is connected to the input end of the phase-shifting network, the second end of the second coupler is connected to the output end of the phase-shifting network, the third and fourth ends of the second coupler are connected to the first end of the fixed-capacitance capacitor, the second end of the fixed-capacitance capacitor is connected to the first and second ends of the transistor, and the controlled end of the transistor is connected to the controlled end of the first phase-shifting circuit.

10. The power amplifier circuit according to any one of claims 1 to 9, characterized in that: The second phase shift circuit is used to adjust the phase difference between the output signal of the first power amplifier branch and the output signal of the second power amplifier branch according to a control signal, the power amplifier circuit inputs the input signal of the first power, and the phase difference is the third phase difference; the power amplifier circuit inputs the input signal of the second power, and the phase difference is the fourth phase difference; the third phase difference is the same as the fourth phase difference.

11. The power amplifier circuit according to any one of claims 1 to 9, characterized in that: The first power amplifier branch is a control signal power amplifier branch, and the second power amplifier branch is a main power amplifier branch; The phase shift network is arranged between the amplifier and the power divider.

12. The power amplifier circuit according to claim 10, characterized in that: The first power amplifier branch is a main power amplifier branch, the second power amplifier branch is a control signal power amplifier branch, and the phase shift network is arranged between the third coupler and the power divider.

13. The power amplifier circuit according to claim 12, characterized in that: The second power amplifier branch includes a fixed phase shift circuit.

14. A radio frequency front end component, characterized in that: It comprises a power amplifier circuit and a low noise amplifier circuit, wherein the power amplifier circuit and the low noise amplifier circuit are coupled, wherein the power amplifier circuit is the power amplifier circuit according to any one of claims 1-13.

15. A radio frequency transceiver system, characterized in that: It comprises an antenna and a radio frequency front-end component, wherein the antenna and the radio frequency front-end component are coupled; the radio frequency front-end component comprises the radio frequency front-end component described in claim 14.

16. An electronic device, characterized in that: It comprises a power supply and a radio frequency transceiver system, wherein the power supply is used to supply power to the radio frequency transceiver system; the radio frequency transceiver system comprises the radio frequency transceiver system according to claim 15.

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