Compensating circuit of radio frequency power amplifier module
By introducing a temperature sensor and detector into the RF power amplifier module to detect changes in temperature and output power, a VTB1 signal is generated. Combined with a superposition module to compensate for the gate voltage at the RF input, the problem of static operating point offset caused by power transistor heating is solved, and more accurate gate voltage compensation is achieved.
Patent Information
- Application Number
- CN202511514446.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-22
- Publication Date
- 2026-02-03
AI Technical Summary
In existing RF power amplifier modules, the temperature rises due to the heat generated by the power transistors, affecting the static operating point. This causes the gate voltage compensation to not match the offset of the static operating point, and the existing compensation method is not effective in nonlinear situations.
Temperature and output power changes are detected by temperature sensors and detectors. VTB1 signal is generated by fitting through multiplier module and controller. Combined with superposition module to compensate gate voltage at RF input, a temperature and output power fitting compensation path is formed to make up for the deviation of temperature compensation path.
It achieves improved static operating point of RF power amplifier module to target state under both online and non-linear temperature offset conditions, and more accurate and stable gate voltage compensation effect.
Smart Images
Figure CN121461900A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of radio frequency circuit, in particular to a compensation circuit of a radio frequency power amplifier module. BACKGROUND
[0002] At present, in the radio frequency power amplifier module, the power transistor will generate serious heat in the use process, which leads to temperature rise, affects the electron mobility inside the radio frequency power amplifier module, and causes the static operating point to deviate. At this time, it is necessary to dynamically adjust the (gate) gate voltage of the radio frequency power amplifier module (usually through voltage compensation radio frequency input end) to maintain the stability of the gain and output power of the radio frequency power amplifier module.
[0003] At present, the compensation gate voltage is usually detected by NTC thermistor in real time, and then the detection signal of NTC thermistor is converted into compensation voltage for compensating the gate voltage. However, the temperature change curve of NTC thermistor and the deviation curve of static operating point with temperature cannot completely coincide linearly, which leads to poor performance of this compensation method in nonlinear compensation. SUMMARY
[0004] In view of the above defects, the purpose of the present application is to provide a compensation circuit of a radio frequency power amplifier module, which solves the problem that the gate voltage compensation of the radio frequency power amplifier module does not match the static operating point deviation of the radio frequency power amplifier module.
[0005] In order to achieve this purpose, the present application adopts the following technical scheme: A compensation circuit of a radio frequency power amplifier module, comprising a temperature sensor, a detector, a multiplication module, a controller and a superposition module; the temperature sensor is used for detecting the temperature of the radio frequency power amplifier module, generating a VTA signal which is transmitted to the multiplication module and the controller respectively; the VTA signal is transmitted to the superposition module after being amplified by the multiplication module; The detector detects the radio frequency output end of the radio frequency power amplifier module, generates a VTB signal which is transmitted to the multiplication module; the VTB signal is transmitted to the controller after being amplified by the multiplication module; The controller generates a VTB1 signal according to the changes of the VTA signal and the VTB signal, and transmits the VTB1 signal to the superposition module; The superposition module superimposes the VTA signal and the VTB signal to generate a VgA signal, and compensates the radio frequency input end of the radio frequency power amplifier module.
[0006] Further, the controller stores a compensation data table, and the compensation data table records the convergence factor μ corresponding to different VTB signals under different VTA signals; The controller substitutes the VTA signal and the VTB signal into the compensation data table to obtain a corresponding convergence factor μ, and the VTB1 signal is generated by fitting the convergence factor μ and the change amount of the VTA signal.
[0007] Further, the formula for generating the VTB1 signal by fitting the convergence factor μ and the change amount of the VTA signal is: VTB1=μ×|(T-T0)|; Wherein VTB1 is the VTB1 signal, T is the VTA signal at this time, and T0 is the VTA signal at the last time.
[0008] Further, the temperature sensor is composed of an analog output temperature sensor chip U1 and its peripheral circuit, and the output end of the analog output temperature sensor chip U1 is coupled to the first input end of the multiplication module and the first input end of the controller through its peripheral circuit.
[0009] Further, the detector is composed of a radio frequency detector chip U3 and its peripheral circuit, and the input end of the radio frequency detector chip U3 is coupled to the radio frequency output end of the radio frequency power amplifier module through its peripheral circuit, and the output end of the radio frequency detector chip U3 is coupled to the second input end of the multiplication module through its peripheral circuit.
[0010] Further, the input end of the radio frequency detector chip U3 and the radio frequency output end of the radio frequency power amplifier module are coupled with an attenuation network and at least one direct current blocking capacitor.
[0011] Further, the multiplication module is composed of an operational amplifier chip U5 with double channels and its peripheral circuit, the input end of the first amplification channel of the operational amplifier chip U5 is used as the first input end of the multiplication module, the output end of the first amplification channel of the operational amplifier chip U5 is used as the first output end of the multiplication module, the input end of the second amplification channel of the operational amplifier chip U5 is used as the second input end of the multiplication module, and the output end of the second amplification channel of the operational amplifier chip U5 is used as the second output end of the multiplication module. The first output end and the second output end of the multiplication module are coupled with the first input end and the second input end of the superposition module respectively.
[0012] Further, the superposition module is a summer with three input ends, the first input end and the second input end of the summer are used as the first input end and the second input end of the superposition module respectively, the third input end of the summer is externally connected with a gate voltage supply voltage VGS, and the output end of the summer is coupled to the radio frequency input end of the radio frequency power amplifier module.
[0013] Furthermore, the temperature sensor and the radio frequency power amplifier module are located in the same heat dissipation path.
[0014] The technical solution provided by this invention can include the following beneficial effects: the gate voltage compensation of the RF power amplifier module is expanded from the current single path of temperature sensor feedback compensation to a joint compensation path of temperature compensation and temperature and output power fitting supplementary path. Specifically, the temperature compensation path directly compensates through the temperature sensor and gain multiplier module; the temperature and output power fitting supplementary path involves the temperature sensor and detector feeding back the VTA signal (representing temperature change) and the VTB signal (representing output power change) to the controller (e.g., MCU, FPGA, etc.), respectively. The controller then uses an algorithm to combine the changes in temperature and output power to fit and generate a VTB1 signal for compensation. The joint compensation of the two paths is achieved by a superimposed circuit, which generates a VgA signal, which is then applied to the RF input terminal of the RF power amplifier module. Thus, the temperature and output power fitting supplementary path compensates for the deviation of the temperature compensation path, and regardless of whether the static operating point of the RF power amplifier module shifts linearly or non-linearly with temperature rise, the gate voltage compensation can improve the static operating point to the target state. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of a compensation circuit for a radio frequency power amplifier module according to one embodiment of the present invention.
[0016] Figure 2 Is it like this? Figure 1 The circuit diagram of the temperature sensor is shown.
[0017] Figure 3 Is it like this? Figure 1 The circuit diagram of the detector is shown.
[0018] Figure 4 Is it like this? Figure 1 The circuit diagram of the RF power amplifier module is shown.
[0019] Figure 5 Is it like this? Figure 1 The circuit diagram of the multiplier module is shown.
[0020] Figure 6 Is it like this? Figure 1 The circuit diagram of the superposition module is shown.
[0021] The components include: temperature sensor 1, detector 2, multiplier module 3, controller 4, superposition module 5, and RF power amplifier module 6. Detailed Implementation
[0022] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.
[0023] In the description of embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.
[0024] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.
[0025] The following is combined Figures 1 to 6 This describes a compensation circuit for an RF power amplifier module according to an embodiment of the present invention.
[0026] A compensation circuit for an RF power amplifier module includes a temperature sensor 1, a detector 2, a multiplier module 3, a controller 4, and a superposition module 5. The temperature sensor 1 is used to detect the temperature of the RF power amplifier module 6 and generate a VTA signal, which is transmitted to the multiplier module 3 and the controller 4 respectively. After being amplified by the multiplier module 3, the VTA signal is transmitted to the superposition module 5. Detector 2 detects the RF output of RF power amplifier module 6 and generates a VTB signal which is transmitted to multiplier module 3. After being amplified by multiplier module 3, the VTB signal is transmitted to controller 4. Controller 4 generates VTB1 signal based on the changes in VTA and VTB signals and transmits it to superposition module 5; The superposition module 5 superimposes the VTA signal and the VTB1 signal to generate the VgA signal, which compensates the RF input terminal of the RF power amplifier module 6.
[0027] In a preferred embodiment of the compensation circuit for an RF power amplifier module, the present invention provides, for example... Figure 1As shown, the gate voltage compensation of the RF power amplifier module 6 has been expanded from the current single path of temperature sensor feedback compensation to a combined compensation path of temperature compensation and temperature and output power fitting. Specifically, the temperature compensation path directly compensates through the gain multiplier module 3 of the temperature sensor 1; the temperature and output power fitting supplementary path involves the temperature sensor 1 and detector 2 feeding back the VTA signal (representing temperature change) and the VTB signal (representing output power change) to the controller 4 (e.g., MCU, FPGA, etc.). The controller 4 then uses an algorithm to combine the temperature and output power changes to fit and generate the VTB1 signal for compensation. The combined compensation of the two paths is achieved by the superimposed unit 5, which generates the VgA signal, which is then applied to the RF input of the RF power amplifier module 6. Thus, the temperature and output power fitting supplementary path compensates for the deviation of the temperature compensation path, ensuring that regardless of whether the static operating point of the RF power amplifier module 6 shifts linearly or non-linearly with temperature rise, the gate voltage compensation can improve the static operating point to the target state.
[0028] Furthermore, the controller 4 stores a compensation data table, which records the convergence factor μ corresponding to different VTB signals under different VTA signals; The controller 4 substitutes the VTA signal and the VTB signal into the compensation data table to obtain the corresponding convergence factor μ. The VTB1 signal is then generated by fitting the change in the VTA signal with the convergence factor μ.
[0029] In this embodiment, based on the characteristic that the output power can directly reflect the change of the static operating point of the RF power amplifier module 6, a compensation data table is obtained from the experiment, which records the convergence factor μ corresponding to different output powers at different temperatures. The convergence factor μ is used to fit the change in temperature and generate the VTB1 signal. Then, the VTB1 signal is superimposed on the VTA signal through the superposition module 5 to correct the deviation of the VTA signal.
[0030] Furthermore, the formula for fitting the convergence factor μ and the change in the VTA signal to generate the VTB1 signal is as follows: VTB1 = μ × |(T-T0)|; Where VTB1 is the VTB1 signal, T is the VTA signal at this time, and T0 is the previous VTA signal.
[0031] In this embodiment, the method of fitting the convergence factor μ and the change in the VTA signal to generate the VTB1 signal can be implemented in the controller 4 using the formula VTB1 = μ × |(T-T0)|. For example, if the compensation data table shows that the convergence factor μ is 1mV, it means that the bias voltage resolution is at the 1mV level, corresponding to a 0.1dB power change. By fitting the temperature change, the amount of correction required for the VTA signal can be determined.
[0032] Furthermore, the temperature sensor 1 is composed of an analog output temperature sensor chip U1 and its peripheral circuits. The output terminal of the analog output temperature sensor chip U1 is coupled to the first input terminal of the multiplier module 3 and the first input terminal of the controller 4 through its peripheral circuits.
[0033] In this embodiment, because the VTA signal output by temperature sensor 1, after being amplified by multiplier module 3, needs to directly compensate for the gate voltage at the RF input terminal of RF power amplifier module 6, temperature sensor 1 needs to be composed of analog output temperature sensor chip U1 (e.g., NST20H-DSCR model) and its peripheral circuitry (the peripheral circuitry can be freely designed according to the circuit recommended in the chip manual, and so on). Figure 2 As shown, the analog voltage (i.e., VTA signal) is directly output to compensate for the gate voltage.
[0034] Furthermore, detector 2 is composed of radio frequency detector chip U3 and its peripheral circuits. The input terminal (such as RFIN terminal) of radio frequency detector chip U3 is coupled to the radio frequency output terminal of radio frequency power amplifier module 6 through its peripheral circuits, and the output terminal (such as VENV terminal) of radio frequency detector chip U3 is coupled to the second input terminal of multiplier module 3 through its peripheral circuits.
[0035] In this embodiment, detector 2 is composed of radio frequency detector chip U3 (e.g., ADL5511 model) and its peripheral circuitry, such as... Figure 3 As shown, it is coupled to the RF output terminal of the RF power amplifier module 6 via the RF terminal, as follows: Figure 4 As shown.
[0036] Furthermore, an attenuation network and at least one DC blocking capacitor are coupled between the input terminal of the RF detector chip U3 and the RF output terminal of the RF power amplifier module 6.
[0037] In this embodiment, to protect the RF detector chip U3 during detection, an attenuation network and at least one DC blocking capacitor need to be coupled between the input terminal of the RF detector chip U3 and the RF output terminal of the RF power amplifier module 6. For example Figure 3 As shown, resistors R15, R16, and R17 form a -3dBm attenuation network used to attenuate radio frequency signals; for example... Figure 3 The capacitors C16 and C18 shown are DC blocking capacitors, used to filter out ripple.
[0038] Furthermore, the multiplier module 3 is composed of an operational amplifier chip U5 with dual channels and its peripheral circuits. The input terminal of the first amplification channel of the operational amplifier chip U5 is used as the first input terminal of the multiplier module 3, the output terminal of the first amplification channel of the operational amplifier chip U5 is used as the first output terminal of the multiplier module 3, the input terminal of the second amplification channel of the operational amplifier chip U5 is used as the second input terminal of the multiplier module 3, and the output terminal of the second amplification channel of the operational amplifier chip U5 is used as the second output terminal of the multiplier module 3. The first and second output terminals of the multiplication module 3 are coupled to the first and second input terminals of the superposition module 5, respectively.
[0039] In this embodiment, the multiplication module 3 is essentially a voltage multiplier, such as... Figure 5 As shown, it is preferably composed of a dual-channel operational amplifier chip U5 (such as the SGM8052 model) and its peripheral circuits. The chip integrates two operational amplifiers (i.e., the first amplification channel and the second amplification channel), which are used to amplify the VTA signal and the VTB signal, respectively.
[0040] Furthermore, the superposition module 5 is an adder with three input terminals. The first and second input terminals of the adder are used as the first and second input terminals of the superposition module 5, respectively. The third input terminal of the adder is connected to the gate voltage supply voltage VGS. The output terminal of the adder is coupled to the RF input terminal of the RF power amplifier module 6.
[0041] In this embodiment, the superposition module 5 is essentially an adder, used to add the VTA signal (i.e., VTA1, written as VTA1 for circuit labeling), the VTB1 signal, and the gate voltage VGS that originally powered the RF input terminal of the RF power amplifier module 6. Therefore, an adder with three input terminals is selected; and the circuit configuration of this adder is not limited, for example... Figure 6 As shown, a dual-channel voltage amplifier chip U4 (such as the SGM8052 model) can be connected via the VTAB terminal to connect the two internal operational amplifiers, forming an adder with three input terminals.
[0042] It is important to note that, such as Figure 4 As shown, there are several ways to connect the VgA terminal to the RF input terminal, which are not limited here. For example, the output terminal of the adder (i.e., the VgA terminal) can be electrically connected to the RF input terminal through a series of parallel capacitors and resistor R14 (equivalent to a feed inductor); or the output terminal of the adder can be electrically connected to the RF input terminal through a microstrip line, an attenuation network, and a feed inductor (for example, if the product power is too high and needs to be reduced). In addition, capacitor C11 is provided to prevent the VgA signal from interfering with the front side of the RF input terminal.
[0043] Furthermore, the temperature sensor 1 and the RF power amplifier module 6 are located in the same heat dissipation path.
[0044] In this embodiment, in order to ensure that the temperature sensor 1 accurately detects the temperature rise of the RF power amplifier module 6, the temperature sensor 1 and the RF power amplifier module 6 are preferably located in the same heat dissipation path; for example, if the RF power amplifier module 6 uses a fan for forward airflow cooling, the temperature sensor 1 should be adjacent to the RF power amplifier module 6 and face the fan at the same time; or if the RF power amplifier module 6 uses a heat sink for cooling, the temperature sensor 1 should be adjacent to the RF power amplifier module 6 and placed on the same heat sink.
[0045] Other configurations and operations of the compensation circuit of an RF power amplifier module according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.
[0046] In the description of this specification, references to terms such as "embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0047] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.
Claims
1. A compensation circuit for an RF power amplifier module, characterized in that: It includes a temperature sensor, a detector, a multiplier module, a controller, and a superposition module; the temperature sensor is used to detect the temperature of the RF power amplifier module and generate a VTA signal, which is transmitted to the multiplier module and the controller respectively; the VTA signal is amplified by the multiplier module and then transmitted to the superposition module. The detector detects the RF output of the RF power amplifier module and generates a VTB signal, which is transmitted to the multiplier module. The VTB signal is then amplified by the multiplier module and transmitted to the controller. The controller, based on the changes in the VTA signal and the VTB signal, fits and generates a VTB1 signal, which is then transmitted to the overlay module. The superposition module superimposes the VTA signal and the VTB signal to generate the VgA signal, which compensates the RF input terminal of the RF power amplifier module.
2. The compensation circuit for an RF power amplifier module according to claim 1, characterized in that: The controller stores a compensation data table, which records the convergence factor μ corresponding to different VTB signals under different VTA signals; The controller substitutes the VTA signal and the VTB signal into the compensation data table to obtain the corresponding convergence factor μ, and then uses the convergence factor μ and the change in the VTA signal to fit and generate the VTB1 signal.
3. The compensation circuit for an RF power amplifier module according to claim 2, characterized in that: The formula for fitting the convergence factor μ and the change in the VTA signal to generate the VTB1 signal is as follows: VTB1 = μ × |(T-T0)|; Where VTB1 is the VTB1 signal, T is the VTA signal at this time, and T0 is the previous VTA signal.
4. The compensation circuit for an RF power amplifier module according to claim 1, characterized in that: The temperature sensor consists of an analog output temperature sensor chip U1 and its peripheral circuits. The output terminal of the analog output temperature sensor chip U1 is coupled to the first input terminal of the multiplication module and the first input terminal of the controller via its peripheral circuits.
5. The compensation circuit for an RF power amplifier module according to claim 4, characterized in that: The detector is composed of an RF detector chip U3 and its peripheral circuits. The input terminal of the RF detector chip U3 is coupled to the RF output terminal of the RF power amplifier module through its peripheral circuits, and the output terminal of the RF detector chip U3 is coupled to the second input terminal of the multiplier module through its peripheral circuits.
6. The compensation circuit for an RF power amplifier module according to claim 5, characterized in that: An attenuation network and at least one DC blocking capacitor are coupled between the input terminal of the RF detector chip U3 and the RF output terminal of the RF power amplifier module.
7. The compensation circuit for an RF power amplifier module according to claim 5, characterized in that: The multiplier module consists of a dual-channel operational amplifier chip U5 and its peripheral circuitry. The input terminal of the first amplification channel of the operational amplifier chip U5 is used as the first input terminal of the multiplier module, and the output terminal of the first amplification channel of the operational amplifier chip U5 is used as the first output terminal of the multiplier module. The input terminal of the second amplification channel of the operational amplifier chip U5 is used as the second input terminal of the multiplier module, and the output terminal of the second amplification channel of the operational amplifier chip U5 is used as the second output terminal of the multiplier module. The first and second output terminals of the multiplication module are coupled to the first and second input terminals of the superposition module, respectively.
8. The compensation circuit for an RF power amplifier module according to claim 7, characterized in that: The superposition module is an adder with three input terminals. The first and second input terminals of the adder are used as the first and second input terminals of the superposition module, respectively. The third input terminal of the adder is connected to the gate voltage supply voltage VGS. The output terminal of the adder is coupled to the RF input terminal of the RF power amplifier module.
9. The compensation circuit for an RF power amplifier module according to claim 1, characterized in that: The temperature sensor and the radio frequency power amplifier module are located in the same heat dissipation path.