CN108809271B - ALC circuit and radio frequency signal source - Google Patents

Abstract

The present invention provides an ALC circuit and a radio frequency signal source. The ALC circuit includes an input port, a radio frequency link connected to the input port, a feedback loop connected to the radio frequency link, and an output port. The radio frequency link includes a variable attenuator connected to the input port, a first radio frequency amplifier connected to the variable attenuator, a temperature compensation module connected to the first radio frequency amplifier, and the temperature compensation module a second radio frequency amplifier connected to the compensation module, and a power divider connected to the second radio frequency amplifier; the feedback loop includes a detector connected to the power divider, and a detector connected to the detector. A digital acquisition module, a digital processing module connected to the digital acquisition module, and a digital-to-analog conversion module connected to the digital processing module. The invention reduces the impact of temperature on the radio frequency link gain, thereby saving calibration time and improving production efficiency.

Description

An ALC circuit and radio frequency signal source

Technical field

The present invention relates to the field of microwave radio frequency technology, and in particular to general instruments in the field of microwave radio frequency. Specifically, it relates to an ALC circuit and a radio frequency signal source.

Background technique

RF signal source is a general instrument in the field of microwave RF, which can provide stable output of specific RF signals. It is widely used in scientific research, education, industry and other fields. The two most important main indicators of an RF signal source are frequency range and amplitude dynamics. The main indicators of amplitude include amplitude accuracy, minimum amplitude step and dynamic range. The automatic level control ALC circuit is the main circuit that realizes the amplitude control part.

To output an RF signal of accurate amplitude, an RF signal source requires an amplitude stabilizing device. The traditional method is to use an analog ALC loop. The specific implementation of the analog ALC loop is shown in Figure 1. The RF input signal is sent to the output of the subsequent amplifier circuit through the variable attenuation unit, and a small part of the signal is split using power distribution at the output end. The amplitude signal is converted into a voltage signal through the detection unit circuit. The voltage signal is compared with the reference voltage value through transformation 1 (such as logarithmic amplification) and output through the integral accumulation circuit. After transformation 2, the variable attenuation circuit in the radio frequency link is controlled.

With the improvement of digital processing capabilities, the stability of digital circuits can reduce the difficulty of analog conversion and improve the stability of the loop. The digital ALC implementation block diagram is shown in Figure 2. The RF signal (RF_in) is output through an adjustable attenuator, RF amplifier and directional coupler; at the same time, the directional coupler couples part of the RF signal to the detector input in a fixed ratio. The detector output signal is directly digitized using the ADC and entered into the FPGA. The processor directly generates the control signal (digital form) of the adjustable attenuator after processing the detection signal, and then converts it into an analog signal through the DAC to control the adjustable attenuator to realize the automatic level control function. Matching resistors are used with directional couplers.

The internal structural block diagram of the processor in Figure 2 is shown in Figure 3. The voltage value sampled by the ADC is subtracted from the zero point value 101 (the ADC sampled voltage when there is no RF signal input), and is sent to the post-stage logarithmic amplifier module 102 through linear The amplification unit 103 compares the output error with the reference DAC 104 and the preset voltage (the preset voltage acts to provide the preset initial voltage of the attenuation curve and improves the ALC loop stabilization time. The last part of Figure 7 has been briefly introduced.) The accumulator 105 adds, The DAC device is controlled through the output stage voltage conversion 106, and the function of the partial conversion of the voltage conversion 106 is to fit the attenuation curve of the attenuation unit. Make its input linear. The linear curve makes it easy to control the attenuation and subsequent function expansion, thereby changing the control voltage or current of the variable attenuator.

In the digital solution, temperature compensation is implemented in the logarithmic amplification 102 module, which greatly improves the impact of temperature on the ALC loop. This solution is feasible in the ALC ON state, and temperature compensation can reduce the impact of temperature on the amplitude in the ALC on state. However, during the implementation of this solution, the impact of temperature changes on the ALC loop needs to be calibrated, which takes a long time and is inefficient. In addition, the ALC OFF state also exists in the ALC module circuit, and the impact of temperature changes on the amplitude in the ALC OFF state cannot be solved in this solution.

Contents of the invention

In order to overcome the above-mentioned defects of the existing technology, the present invention provides an ALC circuit and a radio frequency signal source. By adding a temperature compensation module in the radio frequency link, the impact of temperature on the gain of the radio frequency link is reduced, thereby saving calibration time. ,Increase productivity.

One object of the present invention is to provide an ALC circuit, which includes an input port, a radio frequency link connected to the input port, a feedback loop connected to the radio frequency link, and an output port;

Wherein, the input port is used to input a radio frequency signal;

The radio frequency link includes:

A variable attenuator connected to the input port, used to attenuate the radio frequency signal;

A first radio frequency amplifier connected to the variable attenuator, used to amplify the attenuated radio frequency signal;

a temperature compensation module connected to the first radio frequency amplifier, used for temperature compensation of the amplified radio frequency signal;

a second radio frequency amplifier connected to the temperature compensation module, used to amplify the temperature compensated radio frequency signal;

A power divider connected to the second radio frequency amplifier, used to output the amplified radio frequency signal through the output port, and output a coupled radio frequency signal according to a preset proportional value of the radio frequency signal;

The feedback loop includes:

A detector connected to the power divider, used to convert the coupled radio frequency signal into a corresponding voltage signal;

a digital acquisition module connected to the detector, used to acquire the voltage signal;

a digital processing module connected to the digital acquisition module, configured to output a control signal according to the voltage signal fitting;

A digital-to-analog conversion module connected to the digital processing module is used to perform digital-to-analog conversion on the control signal and then output it to the variable attenuator to control the variable attenuator.

In a preferred embodiment of the present invention, the temperature compensation module is a temperature compensation attenuator or a pi-net attenuator constructed using an inverse thermistor.

In a preferred embodiment of the present invention, the ALC circuit further includes a matching resistor connected to the power divider.

In a preferred embodiment of the present invention, the detector further includes a first temperature sensor for collecting temperature data of the detector, which is called first temperature data.

In a preferred embodiment of the present invention, the digital acquisition module further includes a second temperature sensor for collecting temperature data of the digital acquisition module, which is called second temperature data.

In a preferred embodiment of the present invention, the digital processing module includes: a logarithmic amplifier connected to the digital acquisition module, used to perform logarithmic amplification processing on the voltage signal;

A linear amplification unit connected to the logarithmic amplifier, used to linearly amplify the voltage signal after logarithmic amplification;

The integrating unit connected to the linear amplification module is used to integrate the linearly amplified voltage signal, and send the integrated voltage signal through the loop state control module connected to the integrating unit. To the downstream accumulator connected to the loop state control module;

The post-stage accumulator is used to accumulate the voltage changes corresponding to the preset preset voltage, the voltage signal after integration processing, the first temperature data and the second temperature data, to obtain an accumulated value. value;

A voltage conversion unit connected to the downstream accumulator is used to change the voltage of the accumulated value to obtain a control signal.

In a preferred embodiment of the invention, the logarithmic amplifier includes a first pre-switch;

second preselector switch;

linear amplification unit;

A subtractor and a logarithmic amplification conversion unit connected in parallel with the linear amplification unit, the subtractor and the logarithmic amplification conversion unit being connected in series;

A reference value input unit connected to the subtractor.

In a preferred embodiment of the present invention, the integrating unit includes an integrator and a variation coefficient output unit connected to the integrator.

In a preferred embodiment of the present invention, the subsequent accumulator includes:

A first temperature compensation conversion unit, configured to receive the first temperature data, determine the first temperature change amount according to the first temperature data, and determine the first temperature change amount according to the pre-stored temperature drift index, detection slope and attenuation slope of the detector. Curve, combined with the first temperature change, the first voltage change is calculated;

A second temperature compensation conversion unit is configured to receive the second temperature data, determine a second temperature change amount according to the second temperature data, and combine the second temperature change amount with the pre-stored temperature drift coefficient of the digital acquisition module. The second temperature change is used to calculate the second voltage change;

Preset voltage input unit, used to store preset preset voltage;

Accumulator, respectively connected to the preset voltage input unit, the first temperature compensation conversion unit, the second temperature compensation conversion unit and the loop state control unit, for converting the preset voltage, the first voltage change The amount, the second voltage change amount and the voltage signal output by the loop state control unit are accumulated to obtain an accumulated value.

One object of the present invention is to provide a radio frequency signal source, which includes a radio frequency signal source body and an ALC circuit.

The beneficial effect of the present invention is to provide an ALC circuit and a radio frequency signal source. By adding a temperature compensation module to the radio frequency link and adding a temperature sensor to the detector and digital acquisition module for temperature monitoring, the temperature characteristics of the device can be used to monitor the temperature. Real-time compensation for errors caused by temperature reduces the impact of temperature on the RF link gain, thereby saving calibration time, improving production efficiency, and reducing the impact of the temperature amplitude of the loop in the ALC OFF state.

In order to make the above and other objects, features and advantages of the present invention more clearly understood, preferred embodiments are described in detail below along with the accompanying drawings.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a schematic structural diagram of an analog ALC in the prior art;

Figure 2 is a schematic structural diagram of a digital ALC loop in the prior art;

Figure 3 is a schematic diagram of the internal structure of a digital ALC in the prior art;

Figure 4 is a schematic structural diagram of a radio frequency signal source provided by an embodiment of the present invention;

Figure 5 is a schematic structural diagram of an ALC circuit provided by an embodiment of the present invention;

Figure 6 is a schematic structural diagram of a digital processing module in an ALC circuit provided by an embodiment of the present invention;

Figure 7 is a schematic diagram of the gain curve of the device under high and low temperature conditions of the radio frequency amplifier;

Figure 8 is a schematic diagram of the attenuation curve of the temperature compensation attenuator.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

The principle and spirit of the present invention will be explained in detail below with reference to several representative embodiments of the present invention.

In view of the fact that the temperature compensation of the digital ALC loop in the prior art is implemented in the logarithmic amplification module, it cannot solve the impact of the temperature change on the amplitude in the ALC OFF state, and proposes an ALC circuit and a radio frequency signal source.

FIG. 4 is a structural block diagram of a radio frequency signal source provided by an embodiment of the present invention. Please refer to FIG. 4 . The radio frequency signal source includes a radio frequency signal source body 100 and an ALC circuit 200 .

Figure 5 is a schematic structural diagram of an ALC circuit provided by an embodiment of the present invention. Please refer to Figure 5. The ALC circuit includes an input port, a radio frequency link connected to the input port, and a radio frequency link connected to the feedback loop and output port.

Wherein, the input port (i.e. IN in Figure 5) is used to input a radio frequency signal;

The radio frequency link includes:

A variable attenuator 201 connected to the input port is used to attenuate the radio frequency signal;

The first radio frequency amplifier 202 connected to the variable attenuator is used to amplify the attenuated radio frequency signal;

The temperature compensation module 203 connected to the first radio frequency amplifier is used to perform temperature compensation on the amplified radio frequency signal. In a specific implementation, the temperature compensation module is a temperature compensation attenuator or a pi network attenuator built using an inverse thermistor.

The second radio frequency amplifier 204 connected to the temperature compensation module is used to amplify the temperature compensated radio frequency signal;

In other embodiments of the present invention, the number of radio frequency amplifiers can also be multiple, such as more than two, and they are arranged between the variable attenuator 201 and the temperature compensation module 203 and between the temperature compensation module 203 and the power divider 205 between.

The power divider 205 connected to the second radio frequency amplifier is used to output the amplified radio frequency signal through the output port (ie, OUT in Figure 5), and distribute the radio frequency signal according to the preset The proportional value outputs a coupled radio frequency signal.

In a specific implementation, a proportional value is preset, such as between 1% and 2%. The specific meaning of the proportional value is: a part of the radio frequency signal coupled out of the proportional value is input to the feedback loop. , the proportion of this part of the radio frequency signal to the total total radio frequency signal is this proportional value, and this part of the radio frequency signal becomes a coupled radio frequency signal. In actual use, the ratio value can be set with reference to the sensitivity of the detector 206 .

The feedback loop includes:

A detector 206 connected to the power divider is used to convert the coupled radio frequency signal into a corresponding voltage signal;

The digital acquisition module ADC207 connected to the detector is used to collect the voltage signal;

The digital processing module FPGA208 connected to the digital acquisition module is used to output a control signal according to the voltage signal fitting;

The digital-to-analog conversion module DAC209 connected to the digital processing module is used to perform digital-to-analog conversion on the control signal and then output it to the variable attenuator to control the variable attenuator.

The present invention adds a temperature compensation module to the radio frequency link and participates in the temperature change curve in the reverse compensation link. The components on the RF link in the ALC loop that change significantly due to temperature are mainly RF amplifiers. The gain of common RF amplifiers decreases as the temperature increases, while the differential loss temperature characteristics of the temperature compensation circuit decreases as the temperature increases.

Example: Use a temperature compensation attenuator to optimize the impact of temperature on the trunk line. The gain variation coefficient (Gain Variation Over Temperature) of common amplifier devices is (A)dB/℃, that is, the gain of the amplifier at a specific temperature is:

Gain_T＝[Gain-A*(T-T0)]dB (Formula 1)

Among them, Gain_T is the gain of the amplifier device at T temperature;

T is the real-time temperature;

A is the gain temperature coefficient of the amplifier device (a common coefficient is 0.015dB/℃);

T0 is normal temperature, usually 25℃.

Common amplification chips will give the gain curve of the device under high and low temperature conditions, as shown in Figure 7.

The attenuation curve of the temperature compensation attenuator is opposite, that is, when the temperature is high, the attenuation of the attenuator becomes smaller. The formula is marked as follows:

Att_T(dB)＝Att(dB)-B*(T-T0) (Formula 2)

Among them, Att_T represents the attenuation of the attenuator at T temperature;

Att represents the attenuation at normal temperature;

B is the temperature change coefficient (commonly in the range of 0.003~0.01dB/℃);

T0 is normal temperature, usually 25℃.

The attenuation curve of a common temperature compensation attenuator 203 (built with a thermistor) is shown in Figure 8.

Link gain after hardware compensation

Gain＝[G1-A1*(T-T0)]+[G2-A2*(T-T0)]-ATT_VVA-[Att-B*(T-T0)]-IL_coupler＝G1+G2-ATT_VVA-Att- IL_coupler+(B-A1-A2)*(T-T0) (Formula 3)

Among them, G1A1 represents the gain and gain temperature coefficient of the first radio frequency amplifier 202;

G2A2 represents the gain and gain temperature coefficient of the second radio frequency amplifier 204;

Att B represents the attenuation and temperature coefficient of the temperature compensation module 203;

ATT_VVA is the attenuation of the variable attenuator 201;

IL_coupler is the differential loss of the power divider 205 .

It can be seen from Equation 3 that balancing the relationship between B, A1, and A2 can eliminate the impact of temperature on the RF link.

The above is an ALC circuit provided by the embodiment of the present invention. The radio frequency signal is input from the IN port, passes through the variable attenuator 201, the temperature compensation module 203, the radio frequency amplifier 202/204 and the power divider 205 and reaches the OUT output end. At the same time, the power divider 205 will couple out a radio frequency signal of a certain amplitude according to the preset ratio value of the module and send it to the detector 206. The detector 206 will convert the power amplitude in the link into a corresponding voltage signal (dB~V), and the digital acquisition The module ADC207 collects the converted voltage and sends it to the digital processing module 208 of the subsequent stage. The control signal output by the digital processing module 208 is fitted by the internal algorithm and output after digital-to-analog conversion by the digital-to-analog conversion module 209 to control and adjust the variable Attenuator 201, thereby achieving the amplitude stabilization function.

Please refer to Figure 5. In one embodiment of the present invention, the ALC circuit further includes a matching resistor connected to the power divider. Matching resistors are used with power dividers.

Please refer to Figure 5. In another embodiment of the present invention, the detector further includes a first temperature sensor for collecting temperature data of the detector, which is called first temperature data. The digital acquisition module It also includes a second temperature sensor for collecting temperature data of the digital acquisition module, which is called second temperature data.

Figure 6 is a schematic structural diagram of a digital processing module in an ALC circuit provided by an embodiment of the present invention. Please refer to Figure 6. The digital processing module includes:

The logarithmic amplifier 301 connected to the digital acquisition module is used to perform logarithmic amplification processing on the voltage signal. In Figure 6, the logarithmic amplifier includes a first pre-switch, a second pre-selection switch, a linear amplification unit, a subtractor connected in parallel with the linear amplification unit and a logarithmic amplification conversion unit, the subtractor is connected in series with the logarithmic amplification conversion unit; a reference value input unit connected with the subtractor. The first pre-switch and the second pre-selection switch determine whether the output signal satisfies the linear amplification link or the logarithmic amplification link. When passing through the logarithmic amplification link, the formula is as follows: y=k(ln(x-A)/B), where A is the reference The reference value stored in the value input unit, k and B are the coefficients of the logarithmic amplification transformation unit. The linear amplification transformation unit and the logarithmic amplification curve are finally fitted into a linear and ideal (amplitude ~ voltage) curve.

The linear amplification unit 302 connected to the logarithmic amplifier is used to linearly amplify the voltage signal after logarithmic amplification;

The integration unit 303 connected to the linear amplification module is used to perform integration processing on the linearly amplified voltage signal, and pass the integrated voltage signal through the loop state control unit connected to the integration unit. 304 is sent to the subsequent accumulator 305 connected with the loop state control module. In the embodiment shown in FIG. 6 , the integrating unit includes an integrator and a variation coefficient output unit connected to the integrator. The transformation coefficient is stored in the variation coefficient output unit, which can be understood as the corresponding relationship between the detection curve and the attenuator attenuation curve. The variation coefficient output unit is also connected to the threshold voltage input unit in the subsequent stage accumulator. The initial value of the variation coefficient will be adjusted according to the change of the set reference DAC, which serves to quickly stabilize the ALC loop and improve the loop's stabilization time; improve the stability of the loop and reduce the probability of ALC failure. ALC output dynamics are guaranteed to a certain extent. Add transformation coefficients to the reference DAC and preset DAC data links to directly fit the data relationship between the attenuation voltage curve of the variable attenuation device and the detection characteristic curve of the detection device. Make the loop preset value closer to the final preset voltage, reduce the number of integrations, improve loop stability, and reduce loop stabilization time.

The post-stage accumulator 305 is used to accumulate the voltage changes corresponding to the preset preset voltage, the integrated voltage signal, the first temperature data and the second temperature data, to obtain Accumulated value.

In a specific implementation, the subsequent accumulator includes:

A first temperature compensation conversion unit, configured to receive the first temperature data, determine the first temperature change amount according to the first temperature data, and determine the first temperature change amount according to the pre-stored temperature drift index, detection slope and attenuation slope of the detector. Curve, combined with the first temperature change, the first voltage change is calculated;

A second temperature compensation conversion unit is configured to receive the second temperature data, determine a second temperature change amount according to the second temperature data, and combine the second temperature change amount with the pre-stored temperature drift coefficient of the digital acquisition module. The second temperature change is used to calculate the second voltage change;

Preset voltage input unit, used to store preset preset voltage;

Accumulator, respectively connected to the preset voltage input unit, the first temperature compensation conversion unit, the second temperature compensation conversion unit and the loop state control unit, for converting the preset voltage, the first voltage change The amount, the second voltage change amount and the voltage signal output by the loop state control unit are accumulated to obtain an accumulated value.

In actual use, the initial value of the preset voltage in the preset voltage input unit is a given constant. This initial value may be far different from the stable preset value, and the number of normal loop integrations will be larger. , the integration time is relatively long, and in worse cases, the integration data will be uncontrollable due to unsatisfactory settings, or the controllable interval will be small. Affects the dynamic range of loop operation.

The first temperature compensation conversion unit corresponds to processing data collected by the temperature sensor of the detection device unit. Through the collected temperature signal data of the detector, the periodic temperature of the detector circuit can be detected and calculated. According to the temperature drift index given by the detector and the detection slope of the detector (ALC ON)/the attenuation slope curve of the attenuator (ALC OFF), The initial value of change of the first temperature compensation conversion unit is calculated, and the change relationship of the first temperature compensation conversion unit is further corrected through the change value of the calibrated output port amplitude in the temperature drift state. In actual use, the compensation data of the first temperature compensation conversion unit can be adjusted and switched according to different ALC states. For example, the change curve of the collected data of the first temperature sensor is 200/10°C, that is, when the sensor data changes by 200 (od), it represents a temperature change of 10°C; the temperature drift coefficient of the detector is 0.08dB/10°C. The slope (amplitude ~ detection voltage) is 50mV/dB, and the control slope (attenuation ~ control voltage) of the variable attenuator is -40mV/dB. When the temperature sensor feedback data changes by 200, the corresponding ambient temperature of the detector changes by 10°C. In the ALC ON state, according to the temperature drift coefficient of the detector, the detection amplitude changes by 0.08dB, corresponding to the reference voltage of the detector when the amplitude changes by 0.08dB. It is necessary to adjust 0.08dB*50mV/dB=4mV to ensure the accuracy of the detection amplitude; by calibrating the output amplitude change ΔAdB, the power that the link needs to compensate at this time is AdB, and the first temperature compensation conversion unit is modified to (4+50A) mV can ensure that the output port amplitude of the unit circuit is accurate. In the ALCOFF state, according to the calibration output amplitude change is ΔAdB, according to the control slope of the variable attenuator, the tuning voltage of the variable attenuator needs to be adjusted (-40A) mV to ensure that the output port amplitude of the unit circuit is accurate.

The second temperature compensation conversion unit compensates the digital acquisition module ADC device to collect data from the temperature sensing device. The temperature change of the ADC device is calculated according to the change of the sensor feedback data, the voltage offset of the sampling data is calculated according to the temperature drift coefficient of the ADC device, and the change formula of the second temperature compensation conversion unit is obtained. This transformation relationship is not affected by ALC state switching. The compensation curve is adjusted and corrected according to the temperature change coefficient of the device. The conventional digital temperature compensation part is processed at the input end of the integrator unit 303. This solution cannot compensate for the impact of link temperature changes on the output amplitude after long-term operation. This solution can satisfy the real-time compensation of the temperature impact of the link in different states of ALC ON and ALC OFF.

The voltage conversion module 306 connected to the downstream accumulator is used to change the voltage of the accumulated value to obtain a control signal.

The ADC sampling data is processed by the logarithmic amplifier 301 and output to the linear amplification module 302, converted into data consistent with the reference DAC data format, and adjusted by the integrating unit 303 (the integral input difference (op amp input terminal V+≠V-) is not zero) Its output is accumulated in one direction at a certain rate and is output to the subsequent accumulator 305. The first temperature compensation conversion unit corresponds to the compensation of the temperature drift coefficient of the detection device, the second temperature compensation conversion unit corresponds to the compensation of the temperature drift coefficient of the ADC device, and finally through voltage conversion The unit 306 output controls the DAC device controlling the variable attenuator. Module 304 is a loop control status unit.

To sum up, the present invention provides an ALC circuit and a radio frequency signal source, which makes relevant compensation for temperature compensation under different situations, adds a temperature compensation module in the hardware circuit, and reduces the impact of temperature on the gain of the radio frequency link; in Temperature sensors are added around the detector and digital acquisition module for temperature monitoring. Errors caused by temperature are compensated in real time through the temperature characteristics of the device. The design of the digital temperature compensation part is optimized to save calibration time, improve production efficiency, and reduce the temperature of the loop in the ALCOFF state. The influence of amplitude can reduce the loop lock time, improve the stability of the loop, reduce the data calibration work of the temperature compensation link, and at the same time improve the amplitude stability in the ALC OFF state, improve the system technical indicators, and optimize performance.

Furthermore, although several unit modules of the system are mentioned in the above detailed description, this division is merely not mandatory. In fact, according to embodiments of the present invention, the features and functions of two or more units described above may be embodied in one unit. Likewise, the features and functions of one unit described above can also be further divided into being embodied by multiple units. The terms "module" and "unit" used above may be software and/or hardware that implement predetermined functions. Although the modules described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and contemplated.

Improvements in a technology can be clearly distinguished as improvements in hardware (for example, improvements in circuit structures such as diodes, transistors, switches, etc.) or improvements in software (improvements in method processes). However, with the development of technology, many improvements in today's method processes can be regarded as direct improvements in hardware circuit structures. Designers almost always obtain the corresponding hardware circuit structure by programming the improved method flow into the hardware circuit. Therefore, it cannot be said that an improvement of a method flow cannot be implemented using hardware entity modules. For example, a Programmable Logic Device (PLD) (such as a Field Programmable Gate Array (FPGA)) is such an integrated circuit whose logic functions are determined by the user programming the device. Designers can program themselves to "integrate" a digital system on a PLD, instead of asking chip manufacturers to design and produce dedicated integrated circuit chips. Moreover, nowadays, instead of manually making integrated circuit chips, this kind of programming is mostly implemented using "logic compiler" software, which is similar to the software compiler used in program development and writing. The original code must also be written in a specific programming language, which is called Hardware Description Language (HDL). There is not only one type of HDL, but many types, such as ABEL (Advanced BooleanExpression Language), AHDL ( Altera Hardware Description Language), Confluence, CUPL (Cornell University Programming Language), HDCal, JHDL (Java Hardware Description Language), Lava, Lola, MyHDL, PALASM, RHDL (Ruby Hardware Description Language), etc. The most commonly used one at present is VHDL (Very Hardware Description Language). -High-Speed Integrated CircuitHardware Description Language) and Verilog2. Those skilled in the art should also know that by simply logically programming the method flow using the above-mentioned hardware description languages and programming it into the integrated circuit, the hardware circuit that implements the logical method flow can be easily obtained.

The controller may be implemented in any suitable manner, for example, the controller may take the form of, for example, a microprocessor or processor and a computer readable medium storing computer readable program code (eg, software or firmware) executable by the (micro)processor. , logic gates, switches, Application Specific Integrated Circuit (ASIC), programmable logic controllers and embedded microcontrollers. Examples of controllers include but are not limited to the following microcontrollers: ARC625D, Atmel AT91SAM, Microchip For the PIC18F26K20 and Silicone Labs C8051F320, the memory controller can also be implemented as part of the memory's control logic.

Those skilled in the art also know that in addition to implementing the controller in the form of pure computer-readable program code, the controller can be completely programmed with logic gates, switches, application-specific integrated circuits, programmable logic controllers and embedded logic by logically programming the method steps. Microcontroller, etc. to achieve the same function. Therefore, this controller can be considered as a hardware component, and the devices included therein for implementing various functions can also be considered as structures within the hardware component. Or even, the means for implementing various functions can be considered as structures within hardware components as well as software modules implementing the methods.

For the convenience of description, when describing the above device, the functions are divided into various units and described separately. Of course, when implementing this application, the functions of each unit can be implemented in the same or multiple software and/or hardware.

From the above description of the embodiments, those skilled in the art can clearly understand that the present application can be implemented by means of software plus the necessary general hardware platform. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product in essence or that contributes to the existing technology. The computer software product can be stored in a storage medium, such as ROM/RAM, disk , optical disk, etc., including a number of instructions to cause a computer system (which can be a personal computer, a server, or a network system, etc.) to execute the methods described in various embodiments or certain parts of the embodiments of this application.

Each embodiment in this specification is described in a progressive manner. The same and similar parts between the various embodiments can be referred to each other. Each embodiment focuses on its differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple. For relevant details, please refer to the partial description of the method embodiment.

The application may be used in a variety of general or special purpose computer system environments or configurations. For example: personal computers, server computers, handheld or portable systems, tablet systems, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics systems, network PCs, minicomputers, mainframe computers, including Any of the above systems or distributed computing environments for systems, etc.

The application may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present application may also be practiced in distributed computing environments where tasks are performed by remote processing systems connected through communications networks. In a distributed computing environment, program modules may be located in both local and remote computer storage media including storage systems.

Although this application has been described by way of example, those skilled in the art will appreciate that many modifications and variations can be made without departing from the spirit of this application, and it is intended that the appended claims cover such modifications and variations without departing from the spirit of this application.

Claims (7)

1. An ALC circuit, characterized in that the ALC circuit includes an input port, a radio frequency link connected to the input port, a feedback loop connected to the radio frequency link, and an output port; Wherein, the input port is used to input a radio frequency signal; The radio frequency link includes: A variable attenuator connected to the input port, used to attenuate the radio frequency signal; A first radio frequency amplifier connected to the variable attenuator, used to amplify the attenuated radio frequency signal; a temperature compensation module connected to the first radio frequency amplifier, used for temperature compensation of the amplified radio frequency signal; a second radio frequency amplifier connected to the temperature compensation module, used to amplify the temperature compensated radio frequency signal; A power divider connected to the second radio frequency amplifier, used to output the amplified radio frequency signal through the output port, and output a coupled radio frequency signal according to a preset proportional value of the radio frequency signal; The feedback loop includes: a detector connected to the power divider, used to convert the coupled radio frequency signal into a corresponding voltage signal; a digital acquisition module connected to the detector, used to collect all the voltage signal; a digital processing module connected to the digital acquisition module, used to fit and output a control signal according to the voltage signal; a digital-to-analog conversion module connected to the digital processing module, used to convert the The control signal undergoes digital-to-analog conversion and is output to the variable attenuator to control the variable attenuator; The detector also includes a first temperature sensor, which is used to collect the temperature data of the detector, which is called the first temperature data; the digital acquisition module also includes a second temperature sensor, which is used to collect the temperature data of the digital acquisition module. Temperature data is called second temperature data; the digital processing module includes: a logarithmic amplifier connected to the digital acquisition module, used to perform logarithmic amplification processing on the voltage signal; connected to the logarithmic amplifier The connected linear amplification module is used to linearly amplify the voltage signal after logarithmic amplification; the integration unit connected to the linear amplification module is used to perform integration processing on the linearly amplified voltage signal, and The integrated voltage signal is sent to a subsequent-stage accumulator connected to the loop-state control unit through the loop state control unit connected to the integrating unit; the latter-stage accumulator is used to convert the preset A certain preset voltage, the integrated voltage signal, the first temperature data and the voltage change corresponding to the second temperature data are accumulated to obtain an accumulated value; A voltage conversion unit is used to perform voltage changes on the accumulated value to obtain a control signal. 2. The ALC circuit according to claim 1, wherein the temperature compensation module is a temperature compensation attenuator or a pi-net attenuator constructed using an inverse thermistor. 3. The ALC circuit according to claim 1, wherein the ALC circuit further includes a matching resistor connected to the power divider. 4. The ALC circuit according to claim 1, wherein the logarithmic amplifier includes: First pre-switch; second preselector switch; linear amplification unit; A subtractor and a logarithmic amplification conversion unit connected in parallel with the linear amplification unit, the subtractor and the logarithmic amplification conversion unit being connected in series; A reference value input unit connected to the subtractor. 5. The ALC circuit according to claim 1, wherein the integrating unit includes an integrator and a variation coefficient output unit connected to the integrator. 6. The ALC circuit according to claim 1, characterized in that the latter stage accumulator includes: A first temperature compensation conversion unit, configured to receive the first temperature data, determine the first temperature change amount according to the first temperature data, and determine the first temperature change amount according to the pre-stored temperature drift index, detection slope and attenuation slope of the detector. Curve, combined with the first temperature change, the first voltage change is calculated; A second temperature compensation conversion unit is configured to receive the second temperature data, determine a second temperature change amount according to the second temperature data, and combine the second temperature change amount with the pre-stored temperature drift coefficient of the digital acquisition module. The second temperature change is used to calculate the second voltage change; Preset voltage input unit, used to store preset preset voltage; Accumulator, respectively connected to the preset voltage input unit, the first temperature compensation conversion unit, the second temperature compensation conversion unit and the loop state control unit, for converting the preset voltage, the first voltage change The amount, the second voltage change amount and the voltage signal output by the loop state control unit are accumulated to obtain an accumulated value. 7. A radio frequency signal source, characterized in that the radio frequency signal source includes a radio frequency signal source body and the ALC circuit according to any one of claims 1 to 6.