A method and system for improving power amplifier linearity and efficiency

Abstract

The application relates to a method and system for improving the linearity and efficiency of a power amplifier, wherein the method comprises the following steps: obtaining a radio frequency input signal and distributing the radio frequency input signal into a main path signal and an auxiliary path signal; dynamically adjusting the supply voltage of an amplifying device in a main amplifying path and an auxiliary amplifying path according to the instantaneous envelope of the input signal; using the supply voltage to perform main force power amplification on the main path signal to obtain a main amplifying path signal, and using the supply voltage to perform linear compensation and efficiency enhancement auxiliary amplification on the auxiliary path signal to obtain an auxiliary amplifying path signal; detecting the power level of the two amplifying path signals respectively, generating a static working point adjustment instruction based on the power level grading, adjusting the static working point of the amplifying device generating the two amplifying path signals in response to the instruction, and performing power synthesis on the main amplifying path signal and the auxiliary amplifying path signal at the adjusted static working point to output a linearized radio frequency signal, so that general amplification with high efficiency and high linearity in a full power range is realized.

Description

Technical Field

[0001] This invention relates to the field of radio frequency microwave communication technology, and in particular to a method and system for improving the linearity and efficiency of a power amplifier. Background Technology

[0002] In modern wireless communication systems, power amplifiers are core components of the radio frequency (RF) front-end, and their performance directly determines the quality of the communication link, device power consumption, and heat dissipation design. With the development of 5G and 6G mobile communication pre-research towards larger bandwidths, higher frequency bands, and higher-order modulation, the peak-to-average power ratio (PAPR) of RF signals has significantly increased, placing stringent requirements on power amplifiers to simultaneously achieve high efficiency and high linearity. Traditional linear power amplifiers, to ensure distortion-free signals, typically operate in a deep power back-off state, resulting in extremely low additional efficiency, high power consumption, and a heavy heat dissipation burden. The Doherty architecture only achieves high efficiency near peak power, with severe efficiency degradation in the commonly used low-to-medium power range of communication systems, and poor broadband adaptability. While envelope tracking technology alone can improve efficiency, it requires high device linearity and has insufficient linear margin. Static bias or analog linearization techniques alone cannot adapt to dynamic changes in signal power. Digital predistortion technology has complex algorithms, consumes significant computing power, and has high hardware costs, and cannot fundamentally solve the energy efficiency problem. Furthermore, existing architectures are mostly custom-designed for specific frequency bands or specific devices. Changing the application scenario requires redesigning the circuit, resulting in long R&D cycles and low hardware reuse rates. Therefore, there is an urgent need for a general-purpose power amplifier technology solution that can break through the limitations of frequency bands and devices, while achieving high efficiency and high linearity across the entire power range. Summary of the Invention

[0003] The main objective of this invention is to provide a method and system for improving the linearity and efficiency of a power amplifier. Through coordinated control of dual-path signal distribution, envelope tracking power supply dynamic adjustment, output power level detection feedback, and static operating point graded adjustment, the power amplifier can achieve a universal amplification objective that balances high efficiency and high linearity across the entire power range.

[0004] To achieve the above objectives, the present invention provides a method for improving the linearity and efficiency of a power amplifier, comprising the following steps: Acquire radio frequency input signals and allocate the radio frequency input signals to main path signals and auxiliary path signals; Based on the instantaneous envelope of the radio frequency input signal, the power supply voltage of the amplifier devices in the main amplification path and the amplifier devices in the auxiliary amplification path is dynamically adjusted in real time. The adjusted power supply voltage is used to perform main power amplification on the main path signal to obtain the main amplification path signal. The auxiliary path signal is then subjected to auxiliary amplification for linear compensation and efficiency enhancement to obtain the auxiliary amplification path signal. The power levels of the main amplification path signal and the auxiliary amplification path signal are detected respectively, and a static operating point adjustment command is generated based on the power level classification corresponding to the power level. In response to the static operating point adjustment command, the static operating points of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal are adjusted in stages. At the adjusted static operating point, the main amplification path signal and the auxiliary amplification path signal are combined to output a linearized radio frequency signal.

[0005] Further, the step of allocating the radio frequency input signal into a main path signal and an auxiliary path signal includes: Obtain the power level of the radio frequency input signal; Determine the target power allocation ratio between the main amplification path and the auxiliary amplification path based on the power level; The radio frequency input signal is allocated to the main path signal and the auxiliary path signal according to the target power allocation ratio.

[0006] Furthermore, the step of dynamically adjusting the supply voltage of the amplifying devices in the main amplification path and the amplifying devices in the auxiliary amplification path in real time based on the instantaneous envelope of the radio frequency input signal includes: Extract the instantaneous envelope amplitude of the radio frequency input signal; The instantaneous envelope amplitude is compared with a preset voltage mapping relationship to generate a dynamic power supply voltage reference value; Based on the dynamic power supply voltage reference value, a power supply voltage that follows the instantaneous envelope change is output to the amplifying devices in the main amplification path and the amplifying devices in the auxiliary amplification path.

[0007] Further, the step of amplifying the main path signal to obtain the main amplified path signal by increasing its main power includes: Configure the main power amplifier transistor to the first operating mode; The main path signal is input to the main power amplifier tube via the main input matching network for power amplification. The signal amplified by the main power amplifier tube is output through the main output matching network to obtain the main amplification path signal.

[0008] Further, the step of performing auxiliary amplification on the auxiliary path signal for linear compensation and efficiency enhancement to obtain an auxiliary amplified path signal includes: Configure the auxiliary power amplifier tube to the second operating mode; The auxiliary path signal is input to the auxiliary power amplifier tube via an auxiliary input matching network for power amplification. The signal amplified by the auxiliary power amplifier tube is output through the auxiliary output matching network to obtain the auxiliary amplification path signal.

[0009] Further, the step of detecting the power levels of the main amplification path signal and the auxiliary amplification path signal respectively, and generating a static operating point adjustment command based on the power level classification corresponding to the power level, includes: The power detection values ​​of the main amplification path signal and the auxiliary amplification path signal are collected respectively; The power detection value is compared with preset low power threshold and medium power threshold to determine the power range to which the current power level belongs. The power range includes low power range, medium power range and peak power range. Based on the judgment result, a static operating point adjustment command corresponding to the power range is generated.

[0010] Further, the step of adjusting the static operating points of the amplifying device that generates the main amplification path signal and the amplifying device that generates the auxiliary amplification path signal in stages in response to the static operating point adjustment command includes: Obtain the power range corresponding to the static operating point adjustment command; The adjustment level of the bias voltage is determined based on the power range. The bias voltages of the amplifier devices that generate the main amplification path signal and the amplifier devices that generate the auxiliary amplification path signal are adjusted according to the adjustment levels.

[0011] Furthermore, the step of adjusting the bias voltage according to the aforementioned adjustment levels also includes: When the power range is a low power range, reduce the bias voltage of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal. When the power range is the medium power range, the bias voltage is increased; When the power range is the peak power range, the bias voltage is adjusted to the full bias state.

[0012] Further, the step of power combining the main amplification path signal and the auxiliary amplification path signal includes: Detect the phase difference between the main amplification path signal and the auxiliary amplification path signal; The delay compensation amount is determined based on the detected phase difference; The delay compensation is applied to the auxiliary path signal according to the delay compensation amount, so that the main amplification path signal and the auxiliary amplification path signal are phase synchronized during power combining.

[0013] The present invention also provides a system for improving the linearity and efficiency of a power amplifier, comprising: The radio frequency distribution module is used to acquire radio frequency input signals and distribute the radio frequency input signals into main path signals and auxiliary path signals; The radio frequency amplification module is used to dynamically adjust the power supply voltage of the amplification devices in the main amplification path and the amplification devices in the auxiliary amplification path in real time according to the instantaneous envelope of the radio frequency input signal, and to use the adjusted power supply voltage to perform main power amplification on the main path signal to obtain the main amplification path signal, and to perform auxiliary amplification on the auxiliary path signal for linear compensation and efficiency enhancement to obtain the auxiliary amplification path signal. The signal conditioning module is used to detect the power levels of the main amplification path signal and the auxiliary amplification path signal respectively, and generate a static operating point adjustment command based on the power level classification corresponding to the power level. The bias control module is used to adjust the static operating points of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal in stages in response to the static operating point adjustment command. The synthesized output module is used to combine the main amplification path signal and the auxiliary amplification path signal at the adjusted static operating point, and output the linearized radio frequency signal.

[0014] The method and system for improving the linearity and efficiency of power amplifiers provided by this invention have the following beneficial effects: This invention improves upon the problem of low added efficiency in the low-to-medium power back-off range of traditional power amplifiers by dynamically adjusting the supply voltage of the amplifying device in real time based on the instantaneous envelope of the RF input signal through envelope tracking. This allows the amplifying device to maintain high energy conversion efficiency across the entire power range. Through dual-path collaborative amplification, the main amplification path uses Class AB mode to handle the main power output, while the auxiliary amplification path uses Class A mode to handle linear compensation. The two signals cooperate during power combining, effectively reducing the nonlinear distortion components of the output signal and reducing reliance on complex digital predistortion algorithms. Furthermore, the power detection unit collects the power level of the output signal in real time and performs graded adjustment in conjunction with the dynamic bias control module. In the low-power range, the bias voltage is actively reduced to decrease quiescent current and power consumption; in the medium-power range, the bias voltage is moderately increased to enable main-auxiliary collaborative operation; and in the peak power range, the bias voltage is adjusted to full bias to ensure distortion-free signal amplification. This achieves adaptive optimization of the static operating point according to the output power level. Furthermore, this invention adopts a modular design, and the power amplification devices and matching networks in the main amplification link and auxiliary amplification link can be replaced according to the operating frequency band and power level. The same architecture can adapt to a variety of application scenarios in the frequency band range of 300MHz to 100GHz, avoiding the need to design circuits repeatedly for different frequency bands, reducing R&D costs and the difficulty of hardware reuse. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating a method for improving the linearity and efficiency of a power amplifier according to an embodiment of the present invention. Figure 2 This is a structural block diagram of a system for improving the linearity and efficiency of a power amplifier according to an embodiment of the present invention.

[0016] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0018] The technical architecture provided by this invention has good frequency band compatibility, covering an operating frequency band from 300MHz to 100GHz, and can adapt to the RF front-end requirements of wireless local area networks, 5G mobile communications, 6G mobile communication pre-research, satellite communications, and other broadband wireless communication systems. The following embodiments are all based on this wideband architecture.

[0019] Reference Figure 1 This is a flowchart illustrating a method for improving the linearity and efficiency of a power amplifier proposed in this invention, comprising the following steps: S1, acquire the radio frequency input signal, and allocate the radio frequency input signal to the main path signal and the auxiliary path signal; S2, based on the instantaneous envelope of the radio frequency input signal, dynamically adjust the power supply voltage of the amplifier devices in the main amplification path and the amplifier devices in the auxiliary amplification path in real time, and use the adjusted power supply voltage to perform main power amplification on the main path signal to obtain the main amplification path signal, and perform auxiliary amplification on the auxiliary path signal for linear compensation and efficiency enhancement to obtain the auxiliary amplification path signal. S3, detect the power levels of the main amplification path signal and the auxiliary amplification path signal respectively, and generate a static operating point adjustment command based on the power level classification corresponding to the power level; S4, in response to the static operating point adjustment command, the static operating points of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal are adjusted in stages. S5, at the adjusted static operating point, the main amplification path signal and the auxiliary amplification path signal are combined to output a linearized radio frequency signal.

[0020] As described in step S1 above, in the RF transmission link, the power dynamic range of the input signal is large, making it difficult for a single amplification path to simultaneously achieve high efficiency and high linearity. Therefore, this step acquires the RF input signal to be amplified and decomposes it into a main path signal and an auxiliary path signal through power allocation. The main path signal undertakes the primary power amplification task, focusing on efficiency; the auxiliary path signal undertakes the tasks of linear compensation and efficiency enhancement, focusing on linearity. The power allocation ratio of the two signals can be adaptively adjusted according to the power level of the input signal. This dual-path allocation breaks the performance limitations of traditional single-path amplifiers, achieving a preliminary decoupling of efficiency and linearity.

[0021] As described in step S2 above, after obtaining the main path signal and the auxiliary path signal, this step performs parallel operation of dynamic adjustment of the supply voltage and power amplification of the signal. The instantaneous envelope information of the RF input signal is extracted, and a supply voltage that follows the envelope change is generated in real time based on the magnitude of the envelope amplitude. This voltage is then supplied to the amplifying devices in the main amplification path and the auxiliary amplification path, respectively. Envelope tracking makes the supply voltage of the amplifying devices no longer constant, but dynamically adjusted according to the instantaneous power of the input signal: when the signal envelope is small, the supply voltage is reduced accordingly, thereby reducing static power consumption; when the signal envelope is large, the supply voltage is increased accordingly to ensure output power. Compared with the traditional constant voltage supply method, envelope tracking improves amplification efficiency across the entire power range, especially in the low-to-medium power back-off range commonly used in communication systems. Simultaneously, using the dynamically adjusted supply voltage, the two signals are amplified separately: the main path signal undergoes main power amplification to obtain the main amplified path signal; the auxiliary path signal undergoes auxiliary amplification for linear compensation and efficiency enhancement to obtain the auxiliary amplified path signal. The amplifying devices in the main amplification path can be configured to operate in an efficiency-first mode, while the amplifying devices in the auxiliary amplification path can be configured to operate in a linearity-first mode, allowing the auxiliary path to specifically compensate for any nonlinear distortion that may occur in the main amplification path. The two amplification paths work together, with the main path responsible for outputting the primary power and the auxiliary path responsible for optimizing linearity.

[0022] As described in step S3 above, after the main amplification path signal and the auxiliary amplification path signal are generated, real-time power detection is performed on these two amplified signals. The power detection values ​​of the main amplification path signal and the auxiliary amplification path signal are collected respectively, and these detection values ​​are compared with a preset power threshold to determine the power range to which the current power level belongs. Based on the determination result, this step generates a static operating point adjustment command corresponding to the power range. The command carries information about the current output power level and is used to guide subsequent steps in adjusting the static operating point of the amplification device in stages. Through this real-time detection and command generation, the static operating point of the amplification device can adaptively adjust to follow the dynamic changes in output power.

[0023] As described in step S4 above, the static operating point (SOP) of the amplifying devices is adjusted in stages using the generated SOP adjustment command. Since the power level of the RF input signal changes dynamically over time, a fixed SOP cannot simultaneously meet the requirements of efficiency and linearity across the entire power range. This step correlates the SOP adjustment with the currently detected power level, forming a closed-loop feedback control. The SOP adjustment command carries information about the current power level's range (e.g., low power range, medium power range, or peak power range). The SOP adjustment command is parsed, and differentiated bias voltage adjustment strategies are executed according to different power ranges: in the low power range, the goal is to reduce power consumption; in the medium power range, the goal is to achieve synergistic amplification; and in the peak power range, the goal is to ensure linearity. These adjustments directly affect the amplifying devices that generate the main amplification path signal and the amplifying devices that generate the auxiliary amplification path signal, i.e., changing the bias voltage of these amplifying devices, thereby resetting their SOP. Through staged adjustment, the SOP of the amplifying devices can adaptively adjust in real time to follow changes in output power, ensuring that the subsequent input signal amplification processing is always in an optimal operating state. The quiescent operating point adjustment in this step and the supply voltage adjustment in step S2 are independent but work together. The supply voltage adjustment focuses on dynamically optimizing the energy efficiency of the amplifying device based on the instantaneous envelope of the input signal, while the quiescent operating point adjustment focuses on optimizing the linearity of the amplifying device according to the output power level. Both control the amplifying device from the supply domain and the bias domain respectively, together achieving a balance between high efficiency and high linearity across the entire power range.

[0024] As described in step S5 above, after completing the hierarchical adjustment of the static operating point, the final power combining operation is performed. The main amplification path signal and the auxiliary amplification path signal obtained in step S2 are input to the power combining network for combining. To ensure phase synchronization of the two signals during combining, this step detects the phase difference between the main amplification path signal and the auxiliary amplification path signal, determines the delay compensation amount based on the detected phase difference, and performs delay compensation on the auxiliary path signal, so that the two signals are in phase when they arrive at the combining network, thereby achieving efficient power combining. The combined signal is the linearized RF signal, which maintains high linearity and achieves efficiency optimization across the entire power range. The final output RF signal can be directly fed to the antenna for transmission or used as the input signal for subsequent RF modules.

[0025] In one embodiment, step S1, which involves assigning the radio frequency input signal to a main path signal and an auxiliary path signal, includes: Obtain the power level of the radio frequency input signal; Determine the target power allocation ratio between the main amplification path and the auxiliary amplification path based on the power level; The radio frequency input signal is allocated to the main path signal and the auxiliary path signal according to the target power allocation ratio.

[0026] In practical implementation, the power level of the RF input signal is obtained by coupling a power detection circuit at the front end of the power distribution unit. The power detection circuit can use a diode detector or a logarithmic detector to convert the power of the RF input signal into a DC voltage signal. The amplitude of the DC voltage signal has a predetermined functional relationship with the power level of the input signal. After being digitized by an analog-to-digital converter, the power level value of the current input signal is obtained.

[0027] The target power allocation ratio between the main amplification path and the auxiliary amplification path is determined based on the power level. This embodiment uses a Sub-6GHz communication device as an example. The RF input signal is split into two paths by a power divider, with a fixed allocation ratio of 7:3 between the main and auxiliary amplification paths. 70% of the input signal power is allocated to the main amplification path to handle the primary power output; 30% of the input signal power is allocated to the auxiliary amplification path to handle linear compensation. The 7:3 allocation ratio is chosen because the main power amplifier in the main amplification path is configured in Class AB mode, achieving a balance between efficiency and linearity, suitable for handling most signal power. The auxiliary power amplifier in the auxiliary amplification path is configured in Class A mode, offering better linearity than Class AB but with lower efficiency; therefore, allocating a smaller amount of signal power is sufficient for linear compensation. Experiments have verified that the 7:3 ratio maximizes the system's additional efficiency while maintaining overall linearity. However, the power allocation ratio is not fixed. In other application scenarios, the target power allocation ratio between the main amplification path and the auxiliary amplification path can be adjusted in real time according to the power level of the input signal. For example, when the power level of the input signal is low, the allocation ratio of the auxiliary path can be appropriately increased to enhance the linear compensation effect, and when the power level of the input signal is high, the allocation ratio of the main path can be increased to ensure the main power output.

[0028] The RF input signal is allocated to the main path signal and the auxiliary path signal according to the target power distribution ratio. This embodiment uses a 1-to-2 Wilkinson power divider to achieve this function. The two output ports of this power divider are connected to the input terminals of the main amplification link and the auxiliary amplification link, respectively, and the output signals are the main path signal and the auxiliary path signal. An isolation resistor is connected between the two output branches of the Wilkinson power divider, which can effectively suppress mutual coupling interference between the two output ports and ensure the isolation between the two signals. Through the above process, step S1 achieves power distribution of the RF input signal, allowing the main amplification link to receive most of the input signal power to undertake the main amplification task, and the auxiliary amplification link to receive a small portion of the input signal power to undertake the linear compensation task.

[0029] In one embodiment, step S2, which involves dynamically adjusting the supply voltages of the amplifier devices in the main amplification path and the amplifier devices in the auxiliary amplification path in real time based on the instantaneous envelope of the radio frequency input signal, includes: Extract the instantaneous envelope amplitude of the radio frequency input signal; The instantaneous envelope amplitude is compared with a preset voltage mapping relationship to generate a dynamic power supply voltage reference value; Based on the dynamic power supply voltage reference value, a power supply voltage that follows the instantaneous envelope change is output to the amplifying devices in the main amplification path and the amplifying devices in the auxiliary amplification path.

[0030] In practical implementation, the instantaneous envelope amplitude of the RF input signal is extracted by an envelope detection unit. The RF input signal first passes through a broadband coupler, coupling out a small portion of the signal energy, which is then fed into the envelope detection unit. The envelope detection unit extracts the envelope of the input RF signal and outputs a baseband voltage signal proportional to the instantaneous envelope amplitude. The envelope detection unit can employ diode detection circuits or logarithmic detection circuits, and its key performance indicators include detection bandwidth and detection dynamic range. To meet the requirements of broadband communication systems, the signal response bandwidth of the envelope detection unit should be no less than 20MHz. Simultaneously, the output voltage ripple of the envelope tracking power supply module should be controlled within a range of no more than 50mV to ensure the stability of the supply voltage and avoid the introduction of additional spurious components by the ripple, thus ensuring accurate tracking of the envelope changes of the peak-to-average power ratio (PAPR) signal.

[0031] The instantaneous envelope amplitude is compared with a preset voltage mapping relationship to generate a dynamic supply voltage reference value. The baseband voltage signal output from the envelope detection unit is sent to the non-inverting input of the error operational amplifier. A reference voltage, corresponding to the minimum supply voltage required by the amplification device, is connected to the inverting input of the error operational amplifier. The error operational amplifier compares the instantaneous envelope amplitude with the preset voltage mapping relationship to generate a dynamic supply voltage reference value. The mapping relationship is pre-calibrated based on the output characteristic curve of the amplification device. Specifically, for a given instantaneous envelope amplitude, there exists a minimum supply voltage value that allows the amplification device to achieve the target output power and optimal efficiency. The calibration process is completed through experimental measurements during the device selection stage, and the correspondence between the envelope amplitude and the optimal supply voltage is fixed in the feedback network of the error operational amplifier.

[0032] Based on the dynamic supply voltage reference value, a supply voltage that follows the instantaneous envelope change is output to the amplifying devices in the main amplification path and the amplifying devices in the auxiliary amplification path. The dynamic supply voltage reference value output by the error operational amplifier is sent to the subsequent circuit of the envelope tracking power supply module. This subsequent circuit adopts a topology of cascaded switching regulator and LC filter circuit. The switching regulator adjusts its duty cycle according to the reference voltage, converting the DC input power supply into a pulse width modulated switching waveform. The LC filter circuit filters out the high-frequency components in the switching waveform, outputting a smooth DC supply voltage. The switching frequency of the switching regulator needs to be much higher than the envelope change frequency of the RF input signal to ensure that the output supply voltage can follow the change of the reference voltage in real time. This supply voltage is connected to the drain or collector power supply terminals of the amplifying devices in the main amplification path and the drain or collector power supply terminals of the amplifying devices in the auxiliary amplification path, respectively. When the instantaneous envelope amplitude of the RF input signal is small, the dynamic supply voltage reference value decreases accordingly, the switching regulator reduces its duty cycle, the output supply voltage decreases, thereby reducing the static power consumption of the amplifying devices. When the instantaneous envelope amplitude is large, the dynamic supply voltage reference value increases accordingly, the switching regulator increases its duty cycle, and the output supply voltage rises, ensuring that the amplifying device has sufficient voltage swing to output the required peak power. Through the above process, dynamic envelope tracking and adjustment of the supply voltage of the two amplification links is achieved.

[0033] In one embodiment, the step of performing main power amplification on the main path signal to obtain the main amplified path signal includes: Configure the main power amplifier transistor to the first operating mode; The main path signal is input to the main power amplifier tube via the main input matching network for power amplification. The signal amplified by the main power amplifier tube is output through the main output matching network to obtain the main amplification path signal.

[0034] In practical implementation, the main power amplifier transistor is configured in the first operating mode. The main power amplifier transistor operates in Class AB mode. Class AB mode refers to an amplifier with a conduction angle between Class A and Class B, where its static bias point is higher than Class B but lower than Class A, resulting in a small quiescent current when there is no signal input. In the specific circuit implementation, the static bias voltage of the main power amplifier transistor's gate or base is set to ensure that its quiescent current is greater than the zero quiescent current of a Class B amplifier but less than the large quiescent current of a Class A amplifier. The set value of this bias voltage is determined by the threshold voltage or turn-on voltage of the main power amplifier transistor, typically by adding a positive bias to the threshold voltage. Class AB mode allows the main power amplifier transistor to achieve a balance between efficiency and linearity. Compared to Class A mode, Class AB mode significantly reduces static power consumption and has higher overall amplification efficiency; compared to Class B mode, Class AB mode overcomes the crossover distortion generated near the zero crossing point in Class B amplifiers, resulting in better linearity. This operating mode is suitable for undertaking the main power amplification task.

[0035] The main path signal is input to the main power amplifier transistor via the main input matching network for power amplification. The main input matching network is either a π-type or a T-type passive matching network, composed of inductors, capacitors, or microstrip lines. The π-type matching network consists of three reactive elements, shaped like the Greek letter π, and typically includes two parallel branches and one series branch. The T-type matching network consists of three reactive elements, shaped like the letter T, and typically includes two series branches and one parallel branch. Both topologies can achieve impedance transformation; the choice between π-type and T-type depends on the relative magnitudes of the source and load impedances and the required filtering characteristics. The main function of the main input matching network is to transform the output impedance of the preceding power distribution unit into the optimal source impedance of the main power amplifier transistor to achieve maximum power transfer. Power transfer efficiency reaches its maximum when the source impedance and load impedance are conjugate matched. In specific design, the component parameters of the main input matching network are determined based on the input impedance characteristics and operating frequency band of the main power amplifier transistor. After passing through the main input matching network, the main path signal is sent to the input terminal of the main power amplifier tube. The main power amplifier tube uses the dynamic power supply voltage provided in step S2 and its own set static operating point to amplify the power of the main path signal.

[0036] The signal amplified by the main power amplifier tube is output through the main output matching network to obtain the main amplification path signal. The main output matching network also employs a π-type or T-type passive matching network, constructed from inductors, capacitors, or microstrip lines. Unlike the input matching network, the output matching network not only needs to transform the optimal load impedance of the main power amplifier tube to the input impedance of the subsequent power combining network, but also needs to consider harmonic suppression. Specifically, the output matching network should exhibit low-loss transmission characteristics to the fundamental frequency, while exhibiting high or low impedance characteristics to the second and third harmonics, in order to suppress harmonic component radiation or improve the efficiency and linearity of the amplifier. The signal amplified by the main power amplifier tube is then impedance-transformed and harmonic-suppressed by the main output matching network before being output to obtain the main amplification path signal.

[0037] In one embodiment, the step of performing auxiliary amplification on the auxiliary path signal for linear compensation and efficiency enhancement to obtain an auxiliary amplified path signal includes: Configure the auxiliary power amplifier tube to the second operating mode; The auxiliary path signal is input to the auxiliary power amplifier tube via an auxiliary input matching network for power amplification. The signal amplified by the auxiliary power amplifier tube is output through the auxiliary output matching network to obtain the auxiliary amplification path signal.

[0038] In practical implementation, the auxiliary power amplifier tube is configured in the second operating mode. The auxiliary power amplifier tube operates in Class A mode. Class A mode refers to the amplification state where current flows through the amplifying device throughout the entire cycle of the input signal, with a conduction angle of 360 degrees. In the specific circuit implementation, by setting the static bias voltage of the gate or base of the auxiliary power amplifier tube, its quiescent operating point is located near the center point of the load line, resulting in a large and constant quiescent current. The main characteristic of Class A mode is optimal linearity. Because the amplifying device always operates in the active region and does not enter the cutoff or saturation region, the distortion between the output and input signals is minimal, especially the third-order intermodulation component, which is far lower than in other operating modes. The trade-off for Class A mode is lower efficiency, with a theoretical maximum efficiency of only about 50%, and higher quiescent power consumption. Since the auxiliary amplification path only allocates 30% of the input signal power, the additional power consumption brought by Class A mode is within the acceptable range of overall system efficiency, and the high linearity it provides is crucial for compensating for the nonlinear distortion of the main link.

[0039] The auxiliary path signal is input to the auxiliary power amplifier tube via an auxiliary input matching network for power amplification. The topology of the auxiliary input matching network is similar to that of the main input matching network, also employing a π-type or T-type passive matching network, composed of inductors, capacitors, or microstrip lines. The component parameters of the auxiliary input matching network are independently designed based on the input impedance characteristics of the auxiliary power amplifier tube, without replicating the parameter values ​​of the main input matching network. This is because the device size, operating current, and input impedance of the main power amplifier tube and the auxiliary power amplifier tube may differ, requiring separate matching networks to achieve their respective impedance matching conditions. The output terminal of the auxiliary input matching network is connected to the input terminal of the auxiliary power amplifier tube. After passing through the auxiliary input matching network, the auxiliary path signal is fed into the auxiliary power amplifier tube, which amplifies the auxiliary path signal under the dynamic supply voltage provided in step S2 and its own set Class A static operating point. Since the auxiliary power amplifier tube operates in the Class A mode with optimal linearity, the distortion component of its output signal is extremely small.

[0040] The signal amplified by the auxiliary power amplifier tube is output through an auxiliary output matching network to obtain the auxiliary amplification path signal. The auxiliary output matching network is a π-type or T-type passive matching network, composed of inductors, capacitors, or microstrip lines. The auxiliary output matching network transforms the optimal load impedance of the auxiliary power amplifier tube into the input impedance of the subsequent power combining network. Similar to the main output matching network, the auxiliary output matching network can also be designed with harmonic suppression to reduce the impact of harmonic components in the auxiliary amplification path output signal on the combining efficiency. The signal amplified by the auxiliary power amplifier tube is output through the auxiliary output matching network to obtain the auxiliary amplification path signal. This signal has complementary characteristics to the main amplification path signal; its power amplitude is approximately 30% of the input signal, but its linearity is better than the main amplification path signal. When the two signals are combined in subsequent steps, the linear component in the auxiliary amplification path signal interacts with the nonlinear distortion component in the main amplification path signal, producing a linear compensation effect, thereby reducing the overall output signal distortion level. Through main-auxiliary synergy, the overall power amplifier achieves near-Class A amplifier linearity while maintaining high output power.

[0041] In one embodiment, step S3, which involves detecting the power levels of the main amplification path signal and the auxiliary amplification path signal, and generating a static operating point adjustment command based on the power level classification corresponding to the power levels, includes: The power detection values ​​of the main amplification path signal and the auxiliary amplification path signal are collected respectively; The power detection value is compared with preset low power threshold and medium power threshold to determine the power range to which the current power level belongs. The power range includes low power range, medium power range and peak power range. Based on the judgment result, a static operating point adjustment command corresponding to the power range is generated.

[0042] In specific implementation, power detection values ​​of the main amplification path signal and the auxiliary amplification path signal are collected separately. A power detection unit is set at the output end (i.e., the RF output port) of the power combining network. This power detection unit is coupled to the RF output port and extracts power information from the combined RF output signal. Considering the need to obtain the power levels of the main amplification path signal and the auxiliary amplification path signal separately, coupling detection structures are set at the output ends of the main amplification link and the auxiliary amplification link, or detection points are set at the two input ends of the power combining network. The power detection unit uses a power coupling structure to extract part of the signal energy from the main amplification path signal or the auxiliary amplification path signal, and uses a detection circuit to convert the extracted RF signal power into a DC voltage output. The amplitude of this DC voltage has a predetermined functional relationship with the power level of the input signal. Since the power dynamic range is large in practical applications, a logarithmic amplifier circuit is connected after the detection circuit to convert the logarithmic power value into a linear DC voltage output to simplify subsequent comparison and judgment processing. After the above processing, a first DC detection voltage corresponding to the power level of the main amplification path signal and a second DC detection voltage corresponding to the power level of the auxiliary amplification path signal are obtained respectively.

[0043] The detected power value is compared with preset low-power and medium-power thresholds to determine the power range to which the current power level belongs. This embodiment incorporates a voltage comparison circuit within the dynamic bias control module. The preset low-power and medium-power thresholds are predetermined based on the performance requirements of the power amplifier in different power ranges. Specifically, based on the output characteristic curves of the main and auxiliary power amplifier transistors and the target efficiency and linearity requirements, the boundary power values ​​between the low-power and medium-power ranges, as well as the boundary power values ​​between the medium-power and peak-power ranges, are calibrated. The output voltage value of the power detection unit corresponding to the above boundary power values ​​is obtained through offline testing or simulation, and this voltage value is set as the low-power and medium-power thresholds, respectively. These thresholds are pre-stored in the registers or non-volatile memory of the dynamic bias control module. The voltage comparison circuit compares the DC detection voltage output by the power detection unit with the low-power and medium-power threshold voltages, respectively. When the DC detection voltage is lower than the low-power threshold voltage, the current power level is determined to be in the low-power range. When the DC detection voltage is between the low-power and medium-power threshold voltages, the current power level is determined to be in the medium-power range. When the DC detection voltage is higher than the medium power threshold voltage, the current power level is determined to be in the peak power range. Considering that the power levels of the two signals maintain a fixed distribution ratio under normal operating conditions, power level detection can be performed only on the main amplification path signal. Based on this fixed ratio, the power level range of the auxiliary amplification path signal can be calculated, thereby reducing circuit overhead. The power range includes a low power range, a medium power range, and a peak power range, corresponding to the energy-saving mode or small signal transmission scenario of the communication system, the conventional communication service scenario, and the sudden high-power transmission scenario, respectively.

[0044] Based on the judgment result, a static operating point adjustment command corresponding to the power range is generated. The encoding logic circuit inside the dynamic bias control module receives the judgment result output by the voltage comparison circuit and generates the corresponding static operating point adjustment command according to the preset mapping relationship. This command is output in the form of a digital signal or analog voltage, used to instruct the bias voltage adjustment circuit in step S4 to perform the corresponding adjustment operation. In order to improve the system's response speed and control accuracy, a holding circuit is set at the output of the encoding logic circuit. The output adjustment command is only updated when the power level range changes, avoiding frequent command jumps when the power level is near the boundary between two ranges. Through the above process, real-time detection of the output power level, range judgment, and generation of adjustment commands are completed.

[0045] In one embodiment, step S4, which involves adjusting the static operating points of the amplifier device generating the main amplification path signal and the amplifier device generating the auxiliary amplification path signal in stages in response to the static operating point adjustment command, includes: Obtain the power range corresponding to the static operating point adjustment command; The adjustment level of the bias voltage is determined based on the power range. The bias voltages of the amplifier devices that generate the main amplification path signal and the amplifier devices that generate the auxiliary amplification path signal are adjusted according to the adjustment levels.

[0046] In specific implementation, the power range corresponding to the static operating point adjustment command is obtained. The dynamic bias control module internally includes a command parsing circuit. The input of the command parsing circuit is connected to the output of the encoding logic circuit in step S3, receiving the static operating point adjustment command. The static operating point adjustment command can be represented by a two-digit code, such as 00, 01, and 10, corresponding to the low power range, medium power range, and peak power range, respectively. The command parsing circuit decodes the received digital code to identify the power range corresponding to the current static operating point adjustment command. Specifically, the decoding circuit uses simple combinational logic gates: when the input code is 00, the decoding output L is active, representing the low power range; when the input code is 01, the decoding output M is active, representing the medium power range; and when the input code is 10, the decoding output H is active, representing the peak power range. The decoded result serves as the selection control signal for the subsequent bias voltage adjustment circuit.

[0047] The bias voltage adjustment level is determined based on the power range. The dynamic bias control module pre-stores the mapping relationship between the power range and the adjustment level. This mapping relationship is pre-calibrated based on the linearity and efficiency performance requirements of the power amplifier at different output power levels. For the low power range, the communication system has relatively relaxed requirements for linearity but is more sensitive to power consumption; therefore, the bias voltage adjustment level is set to a decreasing level, aiming to reduce quiescent current and thus power consumption. For the medium power range, the system needs to achieve a balance between efficiency and linearity; therefore, the bias voltage adjustment level is set to an increasing level, aiming to moderately increase the quiescent operating point to enable the coordinated operation of the main amplification link and the auxiliary amplification link. For the peak power range, the system has the most stringent requirements for linearity, needing to ensure distortion-free signal amplification; therefore, the bias voltage adjustment level is set to a full bias level, aiming to make the amplifying device operate in a state of optimal linearity. These adjustment levels are stored in the register of the dynamic bias control module in the form of voltage adjustment amounts; for example, a decreasing level corresponds to a negative voltage increment ΔV1, an increasing level corresponds to a positive voltage increment ΔV2, and a full bias level corresponds to the maximum allowable bias voltage Vmax.

[0048] The bias voltages of the amplifier devices generating the main amplification path signal and the amplifier devices generating the auxiliary amplification path signal are adjusted according to the aforementioned adjustment levels. The dynamic bias control module internally includes a bias voltage adjustment circuit. This circuit consists of a digitally controlled potentiometer and a voltage follower, or a digital-to-analog converter and a linear regulator. The input of the bias voltage adjustment circuit receives the reference bias voltage provided in step S2, and its control terminal receives the gating control signal output by the decoding circuit and the corresponding voltage adjustment value. When the decoding output L is active, the bias voltage adjustment circuit adds a negative voltage increment ΔV1 to the reference bias voltage to generate a reduced bias voltage, which is output to the bias input terminals of the amplifier devices in the main amplification path and the auxiliary amplification path, respectively. When the decoding output M is active, the bias voltage adjustment circuit adds a positive voltage increment ΔV2 to the reference bias voltage to generate a boosted bias voltage. When the decoding output H is active, the bias voltage adjustment circuit directly outputs the maximum allowable bias voltage Vmax to both amplifier devices. The aforementioned adjustments directly alter the static bias voltages of the gates or bases of the main and auxiliary power amplifier transistors, thereby resetting the quiescent operating points of the two amplifying devices. Changes in the quiescent operating point immediately affect the amplification characteristics of the devices for subsequent input signals: increasing the bias voltage increases the quiescent current, improving gain and linearity, but also increasing quiescent power consumption; decreasing the bias voltage decreases the quiescent current and power consumption, but correspondingly weakens linearity. The three adjustment modes are low-power energy-saving mode, medium-power collaborative operation mode, and peak power linear compensation mode, respectively. In low-power energy-saving mode, the bias voltage is lowered to reduce quiescent current; in medium-power collaborative operation mode, the bias voltage is moderately increased to enable collaborative amplification of the main and auxiliary links; and in peak power linear compensation mode, the output is at full bias to ensure distortion-free signal amplification. Through graded adjustment, the quiescent operating point can be adjusted according to changes in output power level, ensuring energy saving in the low-power range, a balance between efficiency and linearity in the medium-power range, and optimal linearity in the peak power range.

[0049] In one embodiment, the step of adjusting the bias voltage according to the adjustment levels further includes: When the power range is a low power range, reduce the bias voltage of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal. When the power range is the medium power range, the bias voltage is increased; When the power range is the peak power range, the bias voltage is adjusted to the full bias state.

[0050] In practical implementation, when the power range is low, a low-power energy-saving mode is entered, reducing the bias voltages of the amplifier devices generating the main amplification path signal and the amplifier devices generating the auxiliary amplification path signal. In the low-power range, the peak-to-average power ratio of the RF input signal is relatively low, and the output power requirement is small; communication systems are typically in energy-saving mode or small-signal transmission scenarios. Maintaining a high static bias voltage at this time would cause the quiescent current of the amplifier devices to consume unnecessary DC power, leading to a decrease in overall efficiency. The bias voltage adjustment circuit in the dynamic bias control module responds to the adjustment command in the low-power range by simultaneously adjusting the gate or base bias voltages of the main power amplifier and the auxiliary power amplifier downwards. This reduction in bias voltage is achieved by conducting a pull-down resistor network in parallel with the bias resistor, or by outputting a lower reference voltage to the setting terminal of the linear regulator through a digital-to-analog converter.

[0051] When the power range is in the medium power range, the system enters a medium power cooperative operating mode, increasing the bias voltage. In the medium power range, the power level of the RF input signal increases, leading to a greater output power demand. The main amplification link and the auxiliary amplification link need to enter a cooperative operating state. If the bias voltage remains at a low level in the low power range, the gain of the amplifying devices will be insufficient, and the linearity will decrease, making it difficult to meet the error vector amplitude requirements of the communication system. The bias voltage adjustment circuit in the dynamic bias control module responds to the adjustment command in the medium power range, adjusting the bias voltage of the main power amplifier and the auxiliary power amplifier upwards. This increase in bias voltage can be achieved by disconnecting the pull-down resistor network in parallel with the bias resistor, or by outputting a higher reference voltage through a digital-to-analog converter. After the bias voltage is increased, the quiescent current and transconductance of the two amplifying devices increase, and the gain returns to normal levels. Simultaneously, the higher quiescent bias voltage shifts the operating point of the amplifying devices towards Class A, improving linearity. At this time, both the main amplification path and the auxiliary amplification path are in a suitable working state. The main link outputs the main power, and the auxiliary link outputs the linear compensation signal. The two work together to meet the performance requirements in the medium power range.

[0052] When the power range is the peak power range, the system enters the peak power linear compensation mode, adjusting the bias voltage to full bias. In the peak power range, the peak-to-average power ratio (PAPR) of the RF input signal reaches its maximum, and the output power requirement approaches the saturation output capability of the amplifying devices. At this point, the linearity requirements of the communication system are most stringent; any nonlinear distortion may lead to out-of-band emission exceeding limits or an increase in the bit error rate. The bias voltage adjustment circuit in the dynamic bias control module responds to the adjustment command of the peak power range, adjusting the bias voltages of the main power amplifier and auxiliary power amplifier to full bias. Full bias refers to the maximum recommended static bias voltage of the amplifying devices within the allowable range of the process specifications, typically corresponding to Class A or near-Class A operating modes. After the bias voltage is adjusted to full bias, the static current of both amplifying devices reaches its maximum, and the conduction angle approaches 360 degrees. At this point, the amplifying devices remain in the conducting state throughout the entire input signal cycle, without entering the cutoff region, resulting in minimal distortion of the output signal. Although the static power consumption is highest in the full bias state, the proportion of the peak power range to the total operating time is usually small, and the overall average efficiency remains controllable. Through the above-mentioned graded bias adjustment, the power amplifier can obtain a suitable static operating point in different power ranges, achieving the optimal configuration of performance across the entire power range.

[0053] In one embodiment, step S5, the step of power combining the main amplification path signal and the auxiliary amplification path signal, includes: Detect the phase difference between the main amplification path signal and the auxiliary amplification path signal; The delay compensation amount is determined based on the detected phase difference; The delay compensation is applied to the auxiliary path signal according to the delay compensation amount, so that the main amplification path signal and the auxiliary amplification path signal are phase synchronized during power combining.

[0054] In practical implementation, phase synchronization processing is required between the main amplification path signal and the auxiliary amplification path signal before power combining. Due to the different signal transmission path lengths in the main and auxiliary amplification links, and the differences in phase shifts introduced by the input and output matching networks, a phase difference may exist between the two signals when they reach the input of the power combining network. If this phase difference is not zero, the two signals cannot be superimposed in phase during combining, resulting in decreased combining efficiency, output power less than the sum of the two signal powers, and some energy being dissipated as heat.

[0055] To address this, this embodiment incorporates a delay compensation unit in the auxiliary amplification link. This delay compensation unit is connected in series in the auxiliary amplification link, located before the auxiliary input matching network or after the auxiliary output matching network. Its function is to apply a fixed delay to the auxiliary path signal to compensate for the inherent phase difference between the main amplification link and the auxiliary amplification link.

[0056] During circuit debugging, a network analyzer or oscilloscope is used to measure the phase response of the main amplification link and the auxiliary amplification link to determine the delay compensation amount. Specifically, the phase shift from the input to the output of the main amplification link is denoted as Φ1, and the phase shift from the input to the output of the auxiliary amplification link is denoted as Φ2. The difference between the two, ΔΦ = Φ1 - Φ2, is the phase difference that needs to be compensated. Based on this phase difference, the corresponding delay compensation amount Δt = ΔΦ / (2πf) is calculated, where f is the center frequency of the operating frequency band. For broadband operating scenarios, multiple frequency points within the operating frequency band are selected for measurement, and the average value of the required compensation amount for each frequency point is taken, or the compensation amount is determined based on the main operating frequency point.

[0057] The delay compensation unit is implemented using a fixed-length microstrip transmission line or coaxial cable. When the required delay is small, additional delay is achieved by increasing the serpentine trace length of the microstrip line in the auxiliary amplification link. When the required delay is large, a lumped-parameter LC delay network or a surface acoustic wave delay line is used. Once the delay compensation unit is designed, its delay characteristics remain fixed throughout the entire operating frequency band, requiring no dynamic adjustment during operation.

[0058] After delay compensation, the total phase shift of the auxiliary amplification link approaches the phase shift of the main amplification link, and the two signals are basically in phase when they reach the input of the adaptive power combining network. At this time, the phase-synchronized main amplification path signal and the auxiliary amplification path signal are sent to the adaptive power combining network for power combining. The two signals are superimposed in phase, the combining efficiency reaches its maximum value, and the output is a linearized RF signal.

[0059] Reference Figure 2 Here is a block diagram of a system for improving the linearity and efficiency of a power amplifier according to an embodiment of the present invention, comprising: The radio frequency distribution module is used to acquire radio frequency input signals and distribute the radio frequency input signals into main path signals and auxiliary path signals; The radio frequency amplification module is used to dynamically adjust the power supply voltage of the amplification devices in the main amplification path and the amplification devices in the auxiliary amplification path in real time according to the instantaneous envelope of the radio frequency input signal, and to use the adjusted power supply voltage to perform main power amplification on the main path signal to obtain the main amplification path signal, and to perform auxiliary amplification on the auxiliary path signal for linear compensation and efficiency enhancement to obtain the auxiliary amplification path signal. The signal conditioning module is used to detect the power levels of the main amplification path signal and the auxiliary amplification path signal respectively, and generate a static operating point adjustment command based on the power level classification corresponding to the power level. The bias control module is used to adjust the static operating points of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal in stages in response to the static operating point adjustment command. The synthesized output module is used to combine the main amplification path signal and the auxiliary amplification path signal at the adjusted static operating point, and output the linearized radio frequency signal.

[0060] Specifically, the RF distribution module uses a 1-to-2 Wilkinson power divider, whose input is connected to the RF input port to receive the RF input signal and distribute it into the main path signal and the auxiliary path signal.

[0061] The RF amplification module includes a main amplification link, an auxiliary amplification link, and an envelope tracking power supply module. In the main amplification link, the main power amplifier transistor is configured in Class AB mode and connected sequentially to the main input matching network and the main output matching network. In the auxiliary amplification link, the auxiliary power amplifier transistor is configured in Class A mode and connected sequentially to the auxiliary input matching network and the auxiliary output matching network, with a delay compensation unit connected in series. The envelope tracking power supply module extracts the instantaneous envelope amplitude of the RF input signal and outputs a supply voltage that follows the envelope change to the power supply terminals of the main and auxiliary power amplifier transistors. The main amplification link uses this voltage to perform main power amplification on the main path signal, outputting the main amplified path signal; the auxiliary amplification link uses the same voltage to perform auxiliary amplification on the auxiliary path signal, outputting the auxiliary amplified path signal.

[0062] The signal conditioning module includes two power detection units and a front-end circuit for a dynamic bias control module. The two power detection units are coupled to the outputs of the main amplification link and the auxiliary amplification link, respectively, acquiring the power levels of the signals from the two amplification paths and converting them into DC detection voltages. The front-end circuit of the dynamic bias control module compares the detected voltages with preset low-power and medium-power thresholds to determine whether the current power falls within the low-power, medium-power, or peak-power range, and generates corresponding static operating point adjustment commands.

[0063] The bias control module is the subsequent circuit of the dynamic bias control module. Its instruction parsing unit receives adjustment commands and decodes them to identify the corresponding power range. The bias voltage adjustment unit adjusts the bias voltage according to the power range: in the low power range, the bias voltage is reduced to decrease quiescent current; in the medium power range, the bias voltage is increased to enable main-auxiliary collaborative operation; and in the peak power range, it is adjusted to full bias to ensure linearity. The adjusted bias voltages are output to the bias terminals of the main power amplifier and the auxiliary power amplifier, respectively. The main power amplifier and the auxiliary power amplifier can be any of the following RF devices: GaN, GaAs, CMOS, or SiC. The specific selection is determined based on a comprehensive consideration of the operating frequency band, output power requirements, and manufacturing costs.

[0064] The output combining module employs an adaptive power combining network, with its two inputs connected to the outputs of the main output matching network and the auxiliary output matching network, respectively. The adaptive power combining network can be implemented using a Wilkinson power combiner or a 3dB bridge. The power combining network features adaptive impedance adjustment, dynamically adjusting the impedance matching state of the combining nodes based on the power ratio of the two signals to optimize combining efficiency. The delay compensation unit in the auxiliary amplification link pre-sets a fixed delay based on the inherent phase difference between the main and auxiliary amplification links to compensate for the phase difference between the two signals. After phase synchronization, the power combining network combines the main amplification path signal and the auxiliary amplification path signal, and its output is connected to the RF output port, outputting a linearized RF signal.

[0065] Of the five modules mentioned above, the RF distribution module, RF amplification module, and synthesized output module constitute the forward signal amplification path, while the signal conditioning module and bias control module constitute the reverse feedback control path, forming a closed-loop system to achieve adaptive adjustment of the static operating point according to the output power level.

[0066] For the specific implementation of each module in the above device example, please refer to the above method embodiments, which will not be repeated here.

[0067] In summary, this invention acquires an RF input signal and allocates it as a main path signal and an auxiliary path signal; dynamically adjusts the supply voltage of the amplifying devices in the main and auxiliary amplifying paths based on the instantaneous envelope of the input signal; uses the supply voltage to amplify the main path signal to obtain the main amplified path signal, and performs linear compensation and efficiency enhancement on the auxiliary path signal to obtain the auxiliary amplified path signal; detects the power levels of the two amplified path signals respectively, and generates static operating point adjustment commands based on the power level classification; adjusts the static operating point of the amplifying devices that generate the two amplified path signals in response to the commands; and combines the main amplified path signal and the auxiliary amplified path signal at the adjusted static operating point to output a linearized RF signal, thereby achieving the goal of universal amplification that balances high efficiency and high linearity across the entire power range.

[0068] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for improving the linearity and efficiency of a power amplifier, characterized in that, Includes the following steps: Acquire radio frequency input signals and allocate the radio frequency input signals to main path signals and auxiliary path signals; Based on the instantaneous envelope of the radio frequency input signal, the power supply voltage of the amplifier devices in the main amplification path and the amplifier devices in the auxiliary amplification path is dynamically adjusted in real time. The adjusted power supply voltage is used to perform main power amplification on the main path signal to obtain the main amplification path signal. The auxiliary path signal is then subjected to auxiliary amplification for linear compensation and efficiency enhancement to obtain the auxiliary amplification path signal. The power levels of the main amplification path signal and the auxiliary amplification path signal are detected respectively, and a static operating point adjustment command is generated based on the power level classification corresponding to the power level. In response to the static operating point adjustment command, the static operating points of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal are adjusted in stages. At the adjusted static operating point, the main amplification path signal and the auxiliary amplification path signal are combined to output a linearized radio frequency signal.

2. The method for improving the linearity and efficiency of a power amplifier according to claim 1, characterized in that, The step of allocating the radio frequency input signal into a main path signal and an auxiliary path signal includes: Obtain the power level of the radio frequency input signal; Determine the target power allocation ratio between the main amplification path and the auxiliary amplification path based on the power level; The radio frequency input signal is allocated to the main path signal and the auxiliary path signal according to the target power allocation ratio.

3. The method for improving the linearity and efficiency of a power amplifier according to claim 1, characterized in that, The step of dynamically adjusting the power supply voltage of the amplifier devices in the main amplification path and the amplifier devices in the auxiliary amplification path in real time based on the instantaneous envelope of the radio frequency input signal includes: Extract the instantaneous envelope amplitude of the radio frequency input signal; The instantaneous envelope amplitude is compared with a preset voltage mapping relationship to generate a dynamic power supply voltage reference value; Based on the dynamic power supply voltage reference value, a power supply voltage that follows the instantaneous envelope change is output to the amplifying devices in the main amplification path and the amplifying devices in the auxiliary amplification path.

4. The method for improving the linearity and efficiency of a power amplifier according to claim 1, characterized in that, The step of amplifying the main path signal to obtain the amplified main path signal includes: Configure the main power amplifier transistor to the first operating mode; The main path signal is input to the main power amplifier tube via the main input matching network for power amplification. The signal amplified by the main power amplifier tube is output through the main output matching network to obtain the main amplification path signal.

5. The method for improving the linearity and efficiency of a power amplifier according to claim 4, characterized in that, The step of performing auxiliary amplification on the auxiliary path signal for linear compensation and efficiency enhancement to obtain an auxiliary amplified path signal includes: Configure the auxiliary power amplifier tube to the second operating mode; The auxiliary path signal is input to the auxiliary power amplifier tube via an auxiliary input matching network for power amplification. The signal amplified by the auxiliary power amplifier tube is output through the auxiliary output matching network to obtain the auxiliary amplification path signal.

6. The method for improving the linearity and efficiency of a power amplifier according to claim 1, characterized in that, The step of detecting the power levels of the main amplification path signal and the auxiliary amplification path signal respectively, and generating a static operating point adjustment command based on the power level classification corresponding to the power level, includes: The power detection values ​​of the main amplification path signal and the auxiliary amplification path signal are collected respectively; The power detection value is compared with preset low power threshold and medium power threshold to determine the power range to which the current power level belongs. The power range includes low power range, medium power range and peak power range. Based on the judgment result, a static operating point adjustment command corresponding to the power range is generated.

7. The method for improving the linearity and efficiency of a power amplifier according to claim 6, characterized in that, The step of adjusting the static operating points of the amplifier device generating the main amplification path signal and the amplifier device generating the auxiliary amplification path signal in stages in response to the static operating point adjustment command includes: Obtain the power range corresponding to the static operating point adjustment command; The adjustment level of the bias voltage is determined based on the power range. The bias voltages of the amplifier devices that generate the main amplification path signal and the amplifier devices that generate the auxiliary amplification path signal are adjusted according to the adjustment levels.

8. The method for improving the linearity and efficiency of a power amplifier according to claim 7, characterized in that, The steps of adjusting the bias voltage according to the aforementioned adjustment levels also include: When the power range is a low power range, reduce the bias voltage of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal. When the power range is the medium power range, the bias voltage is increased; When the power range is the peak power range, the bias voltage is adjusted to the full bias state.

9. The method for improving the linearity and efficiency of a power amplifier according to claim 1, characterized in that, The step of power combining the main amplification path signal and the auxiliary amplification path signal includes: Detect the phase difference between the main amplification path signal and the auxiliary amplification path signal; The delay compensation amount is determined based on the detected phase difference; The delay compensation is applied to the auxiliary path signal according to the delay compensation amount, so that the main amplification path signal and the auxiliary amplification path signal are phase synchronized during power combining.

10. A system for improving the linearity and efficiency of a power amplifier, characterized in that, include: The radio frequency distribution module is used to acquire radio frequency input signals and distribute the radio frequency input signals into main path signals and auxiliary path signals; The radio frequency amplification module is used to dynamically adjust the power supply voltage of the amplification devices in the main amplification path and the amplification devices in the auxiliary amplification path in real time according to the instantaneous envelope of the radio frequency input signal, and to use the adjusted power supply voltage to perform main power amplification on the main path signal to obtain the main amplification path signal, and to perform auxiliary amplification on the auxiliary path signal for linear compensation and efficiency enhancement to obtain the auxiliary amplification path signal. The signal conditioning module is used to detect the power levels of the main amplification path signal and the auxiliary amplification path signal respectively, and generate a static operating point adjustment command based on the power level classification corresponding to the power level. The bias control module is used to adjust the static operating points of the amplifier device that generates the main amplification path signal and the amplifier device that generates the auxiliary amplification path signal in stages in response to the static operating point adjustment command. The synthesized output module is used to combine the main amplification path signal and the auxiliary amplification path signal at the adjusted static operating point, and output the linearized radio frequency signal.

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