Adaptive linearization of power amplifier system

Abstract

The present application relates to an adaptive linearized power amplifier system, comprising: a control module, an input signal channel switching switch, a digital predistortion processing module, an analog predistortion processing module, an RF power amplifier module, an RF switching switch, and a feedback link. The adaptive linearized power amplifier system combines the digital predistortion processing module and the analog predistortion processing module, and controls the control system through the control module and the switching switch to select the digital predistortion linearization mode or the analog predistortion linearization mode, or controls the use of both at the same time, thereby improving the cancellation capability of the system, and is flexible to use, simple to implement, stable in performance, and has a wide range of applications.

Description

Technical Field

[0001] The present application relates to the technical field of power amplifiers, and in particular to an adaptive linear power amplifier system. Background Art

[0002] With the rapid development of mobile communications, the linearity requirements for power amplifiers in modern communication systems are becoming increasingly higher. At present, RF power linearization technology is widely used in various industries such as communications, medical treatment, and transportation. In some occasions, there are strict requirements for the linearity of RF power amplifiers. In order to improve the linearity of the system RF power amplifier, linearization technology is usually used.

[0003] At present, there are four main ways to implement linearization technologies: one is to use power backoff technology; the second is to use feed forward FF (Feed Forward) technology; the third is to use analog pre-distortion (Pre-distortion) technology; the fourth is to use digital pre-distortion DPD (Digital Pre-Distortion) technology. However, the existing linearization technologies have the following disadvantages:

[0004] Power back-off: Make the power amplifier work in the linear region. This method greatly reduces the efficiency of the power amplifier, cannot meet the requirements of multi-carrier, and increases the cost. Feedforward technology: The offset requirements of the feedforward power amplifier are very high, and the amplitude, phase and delay need to be matched. If there are power changes, temperature changes and device aging, the offset failure will occur, and the production process is relatively complicated. Analog pre-distortion: The disadvantage is that the spectral components are less improved, the high-order spectral components are difficult to offset, and the production process is relatively complex. Digital pre-distortion: It requires understanding of the PA distortion characteristics, and the way this characteristic changes is very complex. Its technical difficulty leads to poor producibility.

[0005] Although linearization technologies such as feedforward, analog pre-distortion and digital pre-distortion have been developed and applied in the past two years, highlighting the advantages of high linearity or high efficiency, the complexity and high cost of these technologies have hindered their promotion and application. Summary of the invention

[0006] Based on this, it is necessary to provide a power amplification system capable of adaptive linearization to address the problem of high complexity of the above-mentioned power linearization technology.

[0007] An adaptive linear power amplification system includes: a control module, an input signal channel switching switch, a digital predistortion processing module, an analog predistortion processing module, a radio frequency power amplification module, a radio frequency switching switch and a feedback link.

[0008] The control module is connected to the input signal channel switch and the radio frequency switch through signal control lines respectively;

[0009] The input signal channel switching switch is connected to the radio frequency signal, and the input signal channel switching switch selects to send the radio frequency signal to the input end of the digital pre-distortion processing module or the input end of the analog pre-distortion processing module according to the control signal of the control module;

[0010] The output end of the analog predistortion processing module and the output end of the digital predistortion processing module are respectively connected to the input end of the radio frequency power amplification module;

[0011] The coupled output end of the RF power amplifier module is connected to the RF switching switch, and the RF switching switch is respectively connected to the digital pre-distortion processing module and the analog pre-distortion processing module through feedback links; the RF switching switch selects to turn on the corresponding feedback link and inputs the coupling signal according to the control signal of the control module.

[0012] In one embodiment, the analog predistortion processing module includes a first coupler, an analog predistortion chip, a delay line, and a second coupler;

[0013] The first coupler is respectively connected to the input signal channel switch, the analog predistortion chip and the delay line, and the second coupler is respectively connected to the delay line and the radio frequency power amplifier module;

[0014] The coupling output end of the radio frequency power amplification module is connected to the feedback input end of the analog pre-distortion chip;

[0015] The output end of the analog pre-distortion chip is connected to the radio frequency switch, and the radio frequency switch switches on or off a feedback link with the second coupler according to a control signal of the control module.

[0016] In one embodiment, the control module is connected to the analog pre-distortion chip and is used to control the on and off of the analog pre-distortion chip according to the input signal.

[0017] In one embodiment, the delay line extension time is consistent with the delay time of the analog pre-distortion chip.

[0018] In one embodiment, the digital predistortion processing module includes: a digital predistortion chip, a digital predistortion controller, a first local oscillator, a second local oscillator, a first down-conversion unit, a second down-conversion unit, a first analog-to-digital conversion unit, a second analog-to-digital conversion unit, a digital-to-analog conversion unit, and an up-conversion unit.

[0019] The first local oscillator, the first down-conversion unit, the first analog-to-digital conversion unit, the digital pre-distortion chip, the digital-to-analog conversion unit and the up-conversion unit are connected in sequence; the first down-conversion unit is also connected to the input signal channel switching switch;

[0020] The digital pre-distortion controller is respectively connected to the first analog-to-digital conversion unit, the second analog-to-digital conversion unit and the digital pre-distortion chip;

[0021] The second local oscillator is connected to the up-conversion unit and the second down-conversion unit respectively;

[0022] The second down-conversion unit is also connected to the second analog-to-digital conversion unit and the coupling output end of the radio frequency power amplification module respectively.

[0023] In one embodiment, the control module is connected to the digital pre-distortion chip and is used to control the on and off of the digital pre-distortion chip according to the input signal.

[0024] In one embodiment, a link switch is further included, and the link switch switches on or off the link between the up-conversion unit and the first coupler according to a control signal of the control module.

[0025] In one embodiment, the control module is connected to the RF power amplification module and is used to control the linearization mode of the RF power amplification module according to the input signal.

[0026] In one embodiment, the linearization mode includes: any one of a digital pre-distortion linearization mode and an analog pre-distortion linearization mode or a combination thereof.

[0027] In one embodiment, the control module adopts a single chip microcomputer, an MCU chip or an FPGA chip.

[0028] The above-mentioned adaptive linearized power amplifier system improves the cancellation capability of the system by combining a digital pre-distortion processing module and an analog pre-distortion processing module, and independently selects a digital pre-distortion linearization mode or an analog pre-distortion linearization mode through a control module and a switching switch control system, or controls the use of both at the same time, and can select different linearization modes according to different hardware combinations and usage scenarios. It is flexible in use, simple in implementation, stable in performance, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of an adaptive linear power amplification system in one embodiment;

[0030] Figure 2 FIG. 4 is a principle block diagram of an adaptive linear power amplification system in an embodiment. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0032] The present application provides an adaptive linear power amplifier system, such as Figure 1 As shown, the adaptive linearized power amplification system in this embodiment includes a control module, an input signal channel switching switch, a digital predistortion processing module, an analog predistortion processing module, a radio frequency power amplification module, a radio frequency switching switch and a feedback link. The control module is connected to the input signal channel switching switch and the radio frequency switching switch through signal control lines respectively; the input signal channel switching switch is connected to the radio frequency signal, and the input signal channel switching switch selects to send the radio frequency signal to the input end of the digital predistortion processing module or the input end of the analog predistortion processing module according to the control signal of the control module; the output end of the analog predistortion processing module and the output end of the digital predistortion processing module are respectively connected to the input end of the radio frequency power amplification module; the coupling output end of the radio frequency power amplification module is connected to the radio frequency switching switch, and the radio frequency switching switch is respectively connected to the digital predistortion processing module and the analog predistortion processing module through feedback links; the radio frequency switching switch selects to turn on the corresponding feedback link and send in the coupling signal according to the control signal of the control module.

[0033] The adaptive linearized power amplifier system provided in this embodiment operates in different linearization modes according to different input signals. Specifically, when the control module controls the input signal channel switching switch to send the connected RF signal to the digital pre-distortion processing module, the analog pre-distortion processing module does not work. At this time, the adaptive linearized power amplifier system operates in the digital pre-distortion linearization mode, and the RF switching switch selects to conduct the feedback link with the digital pre-distortion processing module according to the control signal and sends the coupling signal, thereby forming a feedback loop, and adaptively performs the digital pre-distortion linearization cancellation of the power amplifier system in real time.

[0034] When the control module controls the input signal channel switching switch to send the connected RF signal to the analog predistortion processing module, the digital predistortion processing module does not work. At this time, the adaptive linearization power amplifier system works in the analog predistortion linearization mode, and the RF switching switch selects to conduct the feedback link with the analog predistortion processing module according to the control signal and sends the coupling signal, thereby forming a feedback loop and adaptively performing the analog predistortion linearization cancellation of the power amplifier system in real time.

[0035] When the adaptive linearized power amplifier system works in both the digital predistortion linearization mode and the analog predistortion linearization mode, the control module controls the input signal channel switching switch to first send the connected RF signal to the analog predistortion processing module. At this time, the digital predistortion processing module does not work, and the RF switching switch selects to conduct the feedback link with the analog predistortion processing module according to the control signal and sends the coupling signal, thereby forming an analog predistortion feedback loop, and performs analog predistortion linearization cancellation, while saving the analog predistortion parameters at this time. Then, the control module controls the input signal channel switching switch to send the connected RF signal to the digital predistortion processing module. At this time, the analog predistortion processing module does not work, and the RF switching switch selects to conduct the feedback link with the digital predistortion processing module according to the control signal and sends the coupling signal, thereby forming a digital predistortion feedback loop, and performs digital predistortion linearization cancellation, and the saved analog predistortion parameters are superimposed on the digital predistortion parameters and enter the RF power amplifier module together.

[0036] The above-mentioned adaptive linearized power amplifier system improves the cancellation capability of the system by combining a digital pre-distortion processing module and an analog pre-distortion processing module, and independently selects a digital pre-distortion linearization mode or an analog pre-distortion linearization mode through a control module and a switching switch control system, or controls the use of both at the same time, and can select different linearization modes according to different hardware combinations and usage scenarios. It is flexible in use, simple in implementation, stable in performance, and has a wide range of applications.

[0037] Figure 2 FIG. 1 is a block diagram of a power amplifier system with adaptive linearization in one embodiment. Figure 2 As shown, the analog predistortion processing module includes a first coupler, an analog predistortion chip, a delay line and a second coupler, wherein the first coupler is respectively connected to the input signal channel switching switch, the analog predistortion chip and the delay line, and the second coupler is respectively connected to the delay line and the RF power amplifier module; the coupling output end of the RF power amplifier module is connected to the feedback input end of the analog predistortion chip; the output end of the analog predistortion chip is connected to the RF switching switch, and the RF switching switch turns on or off the feedback link with the second coupler according to the control signal of the control module. The extended time of the delay line is consistent with the delayed time of the analog predistortion chip.

[0038] The digital predistortion processing module includes: a digital predistortion chip, a digital predistortion controller, a first local oscillator, a second local oscillator, a first down-conversion unit, a second down-conversion unit, a first analog-to-digital conversion unit, a second analog-to-digital conversion unit, a digital-to-analog conversion unit and an up-conversion unit, wherein the first local oscillator, the first down-conversion unit, the first analog-to-digital conversion unit, the digital predistortion chip, the digital-to-analog conversion unit and the up-conversion unit are connected in sequence; the first down-conversion unit is also connected to the input signal channel switch; the digital predistortion controller is respectively connected to the first analog-to-digital conversion unit, the second analog-to-digital conversion unit and the digital predistortion chip; the second local oscillator is respectively connected to the up-conversion unit and the second down-conversion unit; the second down-conversion unit is also respectively connected to the second analog-to-digital conversion unit and the coupling output end of the radio frequency power amplifier module.

[0039] like Figure 2 As shown, the system further includes a link switch, wherein the link switch switches on or off the link between the up-conversion unit and the first coupler according to a control signal of the control module.

[0040] The control module is connected to the digital pre-distortion chip and the analog pre-distortion chip respectively, and is used to control the on and off of the digital pre-distortion chip and the analog pre-distortion chip according to the input signal. The control module is also connected to the RF power amplifier module, and is used to control the linearization mode of the RF power amplifier module according to the input signal.

[0041] In the power amplification system based on the adaptive linearization as described above, the control module can be implemented by a single chip microcomputer, an MCU (Microcontroller Unit) chip or an FPGA (Field-Programmable Gate Array) chip.

[0042] In specific operation, the control module of the system can set three different working modes according to the needs of users, namely, digital pre-distortion linearization mode, analog pre-distortion linearization mode and simultaneous use of digital pre-distortion linearization and analog pre-distortion linearization mode. It can also be used to improve the linearity of RF power amplifiers in various frequency bands, and its use is flexible and has a wide range of applications.

[0043] When the system works in the digital predistortion linearization mode, the RF signal of the input signal channel switching switch 1 is selected to enter the first down-conversion unit, and the link switch 20 connects the up-conversion unit and the first coupler. The RF switching switch 21 switches the output end of the analog predistortion chip to be connected to the load. The specific working process is as follows:

[0044] The control module controls the analog pre-distortion processing module to not work, and only starts the digital pre-distortion processing module. The input RF signal enters the first down-conversion unit through switch 1. The first down-conversion unit mixes the first local oscillator and the input RF signal to obtain a low-frequency signal. Then the low-frequency signal is converted from a low-frequency signal to a digital signal by the first analog-to-digital conversion unit and enters the input end of the digital pre-distortion chip and the digital pre-distortion controller. The output signal of the digital pre-distortion chip is converted from a digital signal to a low-frequency signal after passing through the digital-to-analog conversion unit. The low-frequency signal is then converted from a low-frequency signal to a RF signal by the up-conversion unit. The frequency of the RF signal is the same as that of the input RF signal, and contains the input RF signal information and the RF correction signal information after digital pre-distortion. Switch 20 connects the up-conversion unit and the first coupler, so the RF signal passes through the delay line and the second coupler after entering the first coupler. Since only the digital pre-distortion linearization technology is used at this time, the analog pre-distortion chip is controlled not to work by the control module. Switch 21 is connected to the load end and is not connected to the second coupler. This prevents the analog predistortion signal from entering the RF power amplifier module. Therefore, the RF signal entering the RF power amplifier module only contains the digital predistortion information. The signal is output after passing through the RF power amplifier module, and a part of the output feedback signal is coupled through the third coupler at the output end and enters the second down-conversion unit through the fourth coupler to become a low-frequency signal. The low-frequency signal is converted into a digital signal after passing through the second analog-to-digital conversion unit. At this time, the output feedback signal becomes a digital signal and then enters the digital predistortion controller. The digital predistortion chip and the digital predistortion controller compare the difference between the signal at the input end and the signal at the reflection end inside the chip, and then generate a corrected digital signal based on this difference, which is superimposed on the digital signal at the input end and outputs a digital signal containing the digital predistortion signal, that is, the corrected digital signal. The digital signal is output at the output end of the digital predistortion chip, and is converted from a digital signal to a low-frequency signal after passing through the digital-to-analog conversion unit. The low-frequency signal is then converted from a low-frequency signal to an RF signal through the up-conversion unit and the previous action is repeated. A feedback loop is formed, so that the digital pre-distortion linearization cancellation of the power amplifier can be performed in real time and adaptively, so as to improve the linearity index of the RF power amplifier.

[0045] When the system works in the analog predistortion linearization mode, the RF signal selection of the input signal channel switching switch 1 all enters the link switch 20, and the output end of the link switch 20 is connected to the first coupler. The RF switching switch 21 switches the output end of the analog predistortion chip to be connected to the second coupler. The specific working process is as follows:

[0046] The control module controls the digital pre-distortion processing module not to work, and only starts the analog pre-distortion processing module. The input RF signal enters switch 20 through switch 1. Switch 20 is connected to the first coupler. In this way, after the input signal passes through the first coupler, a part of the RF signal is coupled to enter the analog pre-distortion chip, and the input signal enters the delay line after passing through the first coupler. Switch 21 connects the second coupler and the output end of the analog pre-distortion chip. Since the time of the delay line extension is consistent with the time of the delay of the analog pre-distortion chip, the input signal after the delay line and the analog pre-distortion signal at the analog pre-distortion output end are combined in the second coupler and output to enter the RF power amplifier module. The output power of the RF power amplifier module couples a part of the output RF signal to the feedback end of the analog pre-distortion chip through the third coupler and the fourth coupler. The analog pre-distortion chip compares the input RF signal and the feedback RF signal and performs analog pre-distortion processing inside the chip, so as to output an analog pre-distortion signal according to the algorithm adaptive adjustment, and synthesizes a signal containing analog pre-distortion with the input signal in the second coupler to enter the RF power amplifier module. A feedback loop is formed, so that the analog pre-distortion linearization cancellation of the power amplifier can be performed adaptively in real time, so as to achieve the purpose of improving the linearity of the radio frequency power amplifier.

[0047] When the system works in the mode of using both digital predistortion linearization and analog predistortion linearization, the RF signal of the input signal channel switching switch 1 enters the first down-conversion unit and the link switch 20 according to the mode control, and the link switch 20 connects the up-conversion unit and the first coupler. The RF switching switch 21 switches the output end of the analog predistortion chip to be connected to the load or the second coupler according to the control module. The specific working process is as follows:

[0048] If the control module controls the analog predistortion processing module to start first, the RF signal of the input signal channel switching switch 1 is controlled to enter the link switch 20, and the output end of the analog predistortion chip is switched to be connected to the second coupler through the RF switching switch 21. At this time, the RF signal enters the first coupler after passing through the switch 20, and then enters the RF power amplifier after passing through the delay line and the output analog predistortion signal of the analog predistortion chip in the second coupler. The output signal is coupled with a part of the signal through the third coupler and the fourth coupler as a feedback signal to enter the feedback end of the analog predistortion chip. An analog predistortion feedback loop is formed to perform analog predistortion linearization cancellation. And the analog predistortion parameters at this time are saved. Then the digital predistortion processing module is started again, and the RF signal of the input signal channel switching switch 1 is controlled to enter the first down-conversion unit, and the output end of the analog predistortion chip is switched to be connected to the load through the RF switching switch 21. At this time, the RF signal enters the first down-conversion unit and the first analog-to-digital conversion unit after passing through the switch 1 to enter the digital predistortion chip. Then it is converted into an analog signal through the digital-to-analog conversion unit and the up-conversion unit. After passing through the switch 20 and the first coupler, the delay line and the second coupler, it enters the RF power amplifier module. The output signal passes through the third coupler and the fourth coupler, and then passes through the second down-conversion unit and the second analog-to-digital conversion unit to become a feedback digital signal and enter the digital pre-distortion controller. The digital pre-distortion controller and the digital pre-distortion chip cooperate with each other to generate a digital signal containing a digital pre-distortion signal and enter the digital-to-analog conversion unit, thereby forming a feedback link of the digital pre-distortion to perform digital pre-distortion linearization cancellation, and the saved analog pre-distortion parameters are superimposed on the digital pre-distortion parameters and enter the RF power amplifier module together. Therefore, the entire system has both an analog pre-distortion feedback link and a digital pre-distortion feedback link. That is, the system uses both analog pre-distortion linearization technology and digital pre-distortion linearization technology, thereby combining the advantages of the two linearization technologies, so that the linearization effect of the power amplifier is better and the linearity improvement is higher.

[0049] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0050] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. An adaptive linear power amplification system, characterized in that: include: control module, input signal channel switching switch, digital pre-distortion processing module, analog pre-distortion processing module, RF power amplifier module, RF switching switch and feedback link, The control module is connected to the input signal channel switch and the radio frequency switch through signal control lines respectively; The input signal channel switching switch is connected to the radio frequency signal, and the input signal channel switching switch selects to send the radio frequency signal to the input end of the digital pre-distortion processing module or the input end of the analog pre-distortion processing module according to the control signal of the control module; The output end of the analog predistortion processing module and the output end of the digital predistortion processing module are respectively connected to the input end of the RF power amplification module; The coupling output end of the RF power amplification module is connected to the RF switching switch, and the RF switching switch is respectively connected to the digital pre-distortion processing module and the analog pre-distortion processing module through the feedback link; the RF switching switch selects to conduct the corresponding feedback link and inputs the coupling signal according to the control signal of the control module; When the adaptive linearized power amplifier system works in both the digital predistortion linearization mode and the analog predistortion linearization mode, the control module controls the input signal channel switching switch to first send the connected RF signal to the analog predistortion processing module. At this time, the digital predistortion processing module does not work. The RF switching switch selects to conduct the feedback link with the analog predistortion processing module according to the control signal and sends the coupling signal, thereby forming an analog predistortion feedback loop, performing analog predistortion linearization cancellation, and saving the analog predistortion parameters at this time; then the control module controls the input signal channel switching switch to send the connected RF signal to the digital predistortion processing module. At this time, the analog predistortion processing module does not work. The RF switching switch selects to conduct the feedback link with the digital predistortion processing module according to the control signal and sends the coupling signal, thereby forming a digital predistortion feedback loop, performing digital predistortion linearization cancellation, and the saved analog predistortion parameters are superimposed on the digital predistortion parameters and enter the RF power amplifier module together.

2. The adaptive linear power amplification system according to claim 1, characterized in that: The analog predistortion processing module includes a first coupler, an analog predistortion chip, a delay line and a second coupler; The first coupler is respectively connected to the input signal channel switch, the analog predistortion chip and the delay line, and the second coupler is respectively connected to the delay line and the radio frequency power amplification module; The coupled output end of the radio frequency power amplification module is connected to the feedback input end of the analog pre-distortion chip through a third coupler and a fourth coupler; The output end of the analog pre-distortion chip is connected to the RF switching switch, the second coupler is connected to the analog pre-distortion chip through the RF switching switch, the RF switching switch turns on or off a feedback link between the analog pre-distortion chip and the second coupler according to a control signal of the control module, and the feedback link includes the RF power amplification module, the third coupler and the fourth coupler which are sequentially connected between the second coupler and the analog pre-distortion chip.

3. The adaptive linear power amplification system according to claim 2, characterized in that: The control module is connected to the analog pre-distortion chip and is used to control the on and off of the analog pre-distortion chip according to an input signal.

4. The adaptive linear power amplification system according to claim 2, characterized in that: The extended time of the delay line is consistent with the delayed time of the analog pre-distortion chip.

5. The adaptive linear power amplification system according to claim 2, characterized in that: The digital predistortion processing module includes: a digital predistortion chip, a digital predistortion controller, a first local oscillator, a second local oscillator, a first down-conversion unit, a second down-conversion unit, a first analog-to-digital conversion unit, a second analog-to-digital conversion unit, a digital-to-analog conversion unit and an up-conversion unit. The first local oscillator, the first down-conversion unit, the first analog-to-digital conversion unit, the digital pre-distortion chip, the digital-to-analog conversion unit and the up-conversion unit are connected in sequence; the first down-conversion unit is also connected to the input signal channel switching switch; The digital pre-distortion controller is respectively connected to the first analog-to-digital conversion unit, the second analog-to-digital conversion unit and the digital pre-distortion chip; The second local oscillator is connected to the up-conversion unit and the second down-conversion unit respectively; The second down-conversion unit is also connected to the second analog-to-digital conversion unit and the coupled output end of the radio frequency power amplification module respectively.

6. The adaptive linear power amplification system according to claim 5, characterized in that: The control module is connected to the digital pre-distortion chip and is used to control the on and off of the digital pre-distortion chip according to an input signal.

7. The adaptive linear power amplification system according to claim 5, characterized in that: A link switch is also included, and the link switch switches on or off the link between the up-conversion unit and the first coupler according to a control signal of the control module.

8. The adaptive linear power amplification system according to any one of claims 1 to 7, characterized in that: The control module is connected to the radio frequency power amplification module and is used to control the linearization mode of the radio frequency power amplification module according to an input signal.

9. The adaptive linear power amplification system according to claim 8, characterized in that: The linearization mode includes: any one of a digital predistortion linearization mode and an analog predistortion linearization mode or a combination thereof.

10. The adaptive linear power amplification system according to any one of claims 1 to 7, characterized in that: The control module adopts a single chip microcomputer, an MCU chip or an FPGA chip.

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