WO2017219324A1

WO2017219324A1 - Method and device for automatic gain control

Info

Publication number: WO2017219324A1
Application number: PCT/CN2016/086950
Authority: WO
Inventors: 李海; 刘娟
Original assignee: 华为技术有限公司
Priority date: 2016-06-23
Filing date: 2016-06-23
Publication date: 2017-12-28
Also published as: CN109314935B; CN109314935A

Abstract

Disclosed are a method and a device for automatic gain control. The method comprises: receiving an analog signal and a first control voltage, adjusting a gain of the analog signal according to the first control voltage, performing an analog-to-digital conversion on the gain-adjusted analog signal to obtain a digital signal; separating N subcarrier signals from the digital signal, N being a positive integer; measuring the sum of average powers of the N subcarrier signals during a first time period to obtain a first power; obtaining a second power on the basis of a power at each sampling point of the digital signal during a second time period; and generating a second control voltage on the basis of the first power and a first threshold as well as the second power and a second threshold, wherein the second control voltage is used to control the gain of the analog signal. Embodiments of the present invention can accurately obtain the average powers of the N subcarrier signals so that the power stability of the subcarrier signals received in a digital receiver is improved, facilitating demodulation.

Description

Method and device for automatically controlling gain

Technical field

The present invention relates to the field of microwave communications, and in particular, to a method and apparatus for automatically controlling gain.

Background technique

In modern communication systems, the requirements for data transmission rates are increasing. In this case, the modulation mode or the extended bandwidth is the main implementation means. However, the enhanced modulation mode is limited by the hardware implementation, and the transmission bandwidth cannot be expanded without limitation due to limited spectrum resources, so the discontinuous carrier aggregation that can improve the spectrum utilization ( Carrier Aggregation (CA) has been urgently needed. Non-continuous CA is a multi-carrier system. Compared with single-carrier systems, its advantages are high spectrum utilization and low hardware cost. Its disadvantage is that the system's Peak Average Rate (PAR) increases and the received signal is stable. Reduce, the interference becomes stronger, and so on. In order to make the system work stably and reliably, some anti-interference technology must be added. Among them, the receiver's Auto Gain Control (AGC) is one of the main techniques to improve the quality of the received signal.

In the microwave transmission system, when microwaves undergo power changes during space transmission, such as sudden rain, fogging, etc., the microwave transmission channel will produce rapid fading, which is reflected in the signal is the receiving end receiving The power is reduced rapidly. AGC technology is an analog to digital converter (ADC) input signal amplitude by adjusting the gain of the control Gain Amplifier (VGA) when the amplitude of the input signal varies greatly. It is basically constant or varies within a small range.

The existing AGC technology monitors the average power of the input signal. When applied to a multi-carrier system, it is affected by continuous wave (CW) interference, resulting in poor power stability of each sub-carrier signal received by the digital receiver, which is not conducive to solution. Tune.

Summary of the invention

It is an object of the present invention to provide a method and apparatus for automatically controlling gain, which solves the prior art When applied to a multi-carrier system, it is susceptible to CW mutations, resulting in poor power stability of each sub-carrier signal received by the digital receiver, which is not conducive to demodulation.

In a first aspect, an automatic gain control method includes: receiving an analog signal and a first control voltage, performing gain on the analog signal according to the first control voltage, and performing analog-to-digital conversion on the analog signal after gain a digital signal; separating N subcarrier signals from the digital signal, wherein N is a positive integer; measuring a sum of average powers of the N subcarrier signals in a first time period to obtain a first power; measuring the digital And obtaining, according to the power of each sampling point, a second power according to the power of each sampling point; obtaining a first error according to the first power and the first threshold, according to the second power And obtaining a second error according to the second threshold, and obtaining an error control coefficient according to the first error and the second error; generating a second control voltage according to the error control coefficient, wherein the second control voltage is used Controlling the gain of the analog signal.

The embodiment of the invention can accurately obtain the average power of the N subcarrier signals, reduce the influence of the CW mutation, and improve the power stability of each subcarrier signal received in the digital receiver, which is beneficial to demodulation.

With reference to the first aspect, in a first possible implementation manner of the first aspect, the separating the N subcarrier signals from the digital signal specifically includes: dividing the digital signal into N channels, each of the digital signals Similarly, the Kth subcarrier signal of the Kth digital signal is moved to zero frequency by the spectrum shifting technique, and then matched filtering is performed to separate the Kth subcarrier signal, where K is a positive integer not greater than N. The embodiment of the invention provides a specific obtaining manner of N subcarrier signals.

With reference to the first aspect, in a second possible implementation manner of the first aspect, the obtaining, by the first power and the first threshold, the first error specifically includes: the first threshold minus the first The second error is obtained according to the second power and the second threshold. The second threshold is obtained by subtracting the second power from the second threshold to obtain the second error.

In conjunction with the first aspect or the first or second possible implementation of the first aspect, in a third possible implementation manner of the first aspect, the obtaining a second according to the power of each sampling point The power specifically includes: measuring, as the second power, an average power of a digital signal sampling point whose power is greater than the second threshold. The second power of the embodiment of the present invention exceeds the second threshold The average power of the digital signal sampling point can reduce the jitter of the second power and increase system stability.

In conjunction with the third possible implementation of the first aspect, in a fourth possible implementation manner of the first aspect, the obtaining an error control coefficient according to the first error and the second error includes: Multiplying the first error by the first factor to obtain a first control coefficient, the second error multiplied by the second factor, to obtain a second control coefficient, wherein the first factor and the second factor are preset The value of the error control coefficient is obtained according to the first control coefficient and the second control coefficient.

The error extraction operation in the embodiment of the present invention combines the second power of the measured digital signal and the average power of the N subcarriers, avoiding the use of measuring the average power of the N subcarriers alone, and the estimation is caused by not considering the influence of the CW. The peak power of the digital signal is too small, resulting in a situation where the signal power entering the ADC exceeds the dynamic range.

With reference to the first aspect or the first or second possible implementation manner of the first aspect, in a fifth possible implementation manner of the first aspect, the obtaining a second according to the power of each sampling point The power specifically includes: measuring a peak power of a sampling point of the digital signal as the second power; after obtaining the second power, the method further includes: calculating the digital signal in the second time period The average power, the digital signal peak-to-average ratio is obtained according to the second power and the average power, and the second threshold is obtained according to the peak-to-average ratio of the digital signal, wherein the digital signal peak-to-average ratio is larger, The second threshold is smaller.

The second threshold of the embodiment of the present invention changes with the change of the peak-to-average ratio of the digital signal, and the dynamic range of the ADC can be more fully utilized compared with the fixed second threshold, and the signal noise of the signal entering the ADC The ratio is proportional to the effective number of bits of the ADC, and the more fully utilized the dynamic range of the ADC, the higher the effective number of bits of the ADC, so embodiments of the present invention can make the input data have a higher signal to noise ratio.

With reference to the fifth possible implementation manner of the first aspect, in a sixth possible implementation manner of the first aspect, the obtaining an error control coefficient according to the first error and the second error includes: Multiplying the first error by the first factor to obtain a first correction error, the first correction error is multiplied by a third factor to obtain a first control coefficient, and the second error is multiplied by a second factor to obtain a second control coefficient Where the first factor and the second factor are preset numbers a value, the third factor being a value that varies with a peak-to-average ratio of the digital signal; and the error control coefficient is obtained according to the first control coefficient and the second control coefficient.

In conjunction with the sixth possible implementation of the first aspect, in a seventh possible implementation of the first aspect, the third factor decreases as the peak-to-average ratio of the digital signal decreases. In the embodiment of the present invention, the proportion of the first error and the second error in the error control coefficient may be adjusted according to the peak-to-average ratio of the digital signal to improve system performance.

In conjunction with the fifth possible implementation of the first aspect, in an eighth possible implementation manner of the first aspect, the obtaining an error control coefficient according to the first error and the second error specifically includes: The first error is multiplied by the first factor to obtain a first control coefficient, the second error is multiplied by the second factor to obtain a second correction error, and the second correction error is multiplied by a fourth factor to obtain a second control coefficient. Wherein the first factor and the second factor are preset values, the fourth factor being a value that varies with a peak-to-average ratio of the digital signal; according to the first control coefficient and the The second control coefficient obtains the error control coefficient.

In conjunction with the eighth possible implementation of the first aspect, in a ninth possible implementation of the first aspect, the fourth factor increases as the peak-to-average ratio of the digital signal decreases.

With reference to the sixth possible implementation manner of the first aspect, in a tenth possible implementation manner of the first aspect, the obtaining an error control coefficient according to the first control coefficient and the second control coefficient includes: Adding or multiplying the first control coefficient and the second control coefficient to obtain the error control coefficient; and generating the second control voltage according to the error control coefficient specifically includes: controlling the error The coefficients are subjected to loop filtering, numerically controlled oscillation, and low pass filtering to generate the second control voltage.

With reference to the sixth possible implementation manner of the first aspect, in an eleventh possible implementation manner of the first aspect, the obtaining an error control coefficient according to the first control coefficient and the second control coefficient The method includes: performing loop filtering on the first control coefficient and the second control coefficient, respectively, to obtain a filtered first control coefficient and a filtered second control coefficient, and the filtered first control coefficient and Adding or multiplying the filtered second control coefficients to obtain the error control coefficient; and generating the second control voltage according to the error control coefficient specifically includes: performing numerical control oscillation on the error control coefficient and low The second control voltage is generated by a filtering process.

In a second aspect, an automatic gain control device is provided, comprising: a voltage controlled gain amplifier, an analog to digital converter, a subcarrier power detector, a digital signal detector, an error extractor, and a control voltage generator,

The voltage control gain amplifier is configured to receive an analog signal and a first control voltage, perform a gain on the analog signal according to the first control voltage, and send the analog signal after the gain to the analog to digital converter;

The analog-to-digital converter is configured to receive the analog signal after the gain from the voltage control gain amplifier, perform analog-to-digital conversion on the analog signal after the gain, obtain a digital signal, and send the digital signal to the Determining a subcarrier power detector and the digital signal detector;

The subcarrier power detector is configured to receive the digital signal from the analog to digital converter, separate N subcarrier signals from the digital signal, and measure an average of the N subcarrier signals in a first time period a sum of powers, a first power is obtained, and the first power is sent to the error extractor, where N is a positive integer;

The digital signal detector is configured to receive the digital signal from the analog to digital converter, and measure power of each sampling point of the digital signal in a second time period, according to the power of each sampling point, a second power, the second power is sent to the error extractor;

The error extractor is configured to receive the first power from the subcarrier power detector, receive the second power from the digital signal detector, and obtain a first according to the first power and the first threshold An error, according to the second power and the second threshold, obtaining a second error, according to the first error and the second error, obtaining an error control coefficient, and sending the error control coefficient to the control voltage Device

The control voltage generator is configured to receive the error control coefficient from the error extractor, obtain a second control voltage according to the error control coefficient, and send the second control voltage to the voltage control gain amplifier, Wherein the second control voltage is used to control a gain of the analog signal.

The embodiment of the invention can accurately obtain the average power of the N subcarrier signals, reduce the influence of the CW mutation, and improve the power stability of each subcarrier signal received by the digital receiver, which is beneficial to demodulation.

With reference to the second aspect, in a first possible implementation manner of the second aspect, the subcarrier The power detector is specifically configured to: divide the digital signal into N channels, and each of the digital signals is the same, and move the Kth subcarrier signal of the Kth digital signal to a zero frequency by a spectrum shifting technique, and then perform matching filtering and separation. The Kth subcarrier signal is output, where K is a positive integer not greater than N. The embodiment of the present invention provides a specific acquisition manner of N subcarrier signals.

With reference to the second aspect, in a second possible implementation manner of the second aspect, the error extractor is specifically configured to: subtract the first power from the first threshold, and obtain the first error; The second threshold is subtracted from the second power to obtain the second error.

In conjunction with the second aspect or the first or second possible implementation of the second aspect, in a third possible implementation of the second aspect, the digital signal detector is specifically configured to: In the second time period, the power of the digital signal sampling point whose power is greater than the second threshold is used as the second power. The second power of the embodiment of the present invention takes the average power of the digital signal sampling point exceeding the second threshold, which can reduce the jitter of the second power and increase the stability of the system.

In conjunction with the third possible implementation of the second aspect, in a fourth possible implementation manner of the second aspect, the error extractor is specifically configured to: the first error multiplied by the first factor to obtain the first a control coefficient, the second error multiplied by a second factor, to obtain a second control coefficient, wherein the first factor and the second factor are preset values; according to the first control coefficient and the The second control coefficient obtains the error control coefficient.

The error extractor in the embodiment of the present invention combines the second power of the measured digital signal and the average power of the N subcarriers, avoiding the use of measuring the average power of the N subcarriers alone, and the estimation is caused by not considering the influence of the CW. The peak power of the digital signal is too small, resulting in a situation where the signal power entering the ADC exceeds the dynamic range.

In conjunction with the second aspect or the first or second possible implementation of the second aspect, in a fifth possible implementation of the second aspect, the digital signal detector further includes: a peak power detector, an average a power detector and a peak-to-average ratio calculator, the peak power detector for detecting a peak power of the digital signal during a second time period, and transmitting the peak power to the peak-to-average ratio calculator; An average power detector for detecting an average power of the digital signal during a second time period, transmitting the average power to the peak-to-average ratio calculator; the peak-to-average ratio calculator for using the peak Receiving, by the power detector, the peak power, receiving the average power from the average power detector, and calculating a peak-to-average ratio of digital signals in a second time period, the number being The signal peak to average ratio is sent to the error extractor.

In conjunction with the fifth possible implementation of the second aspect, in a sixth possible implementation of the second aspect, the error extractor is further configured to receive the digital signal peak from the peak-to-average ratio calculator The second threshold is obtained according to the peak-to-average ratio of the digital signal, wherein the digital signal peak-to-average ratio is larger, and the second threshold is smaller.

In conjunction with the sixth possible implementation of the second aspect, in a seventh possible implementation of the second aspect, the error extractor is specifically configured to: the first error multiplied by the first factor, to obtain the first Correcting an error, the first correction error multiplied by a third factor to obtain a first control coefficient, the second error multiplied by a second factor, to obtain a second control coefficient, wherein the first factor and the second The factor is a preset value, and the third factor is a value that varies with a peak-to-average ratio of the digital signal; and the error control coefficient is obtained according to the first control coefficient and the second control coefficient.

In conjunction with the seventh possible implementation of the second aspect, in an eighth possible implementation of the second aspect, the third factor decreases as the peak-to-average ratio decreases. In the embodiment of the present invention, the proportion of the first error and the second error in the error control coefficient may be adjusted according to an actual peak-to-average ratio condition to improve system performance.

In conjunction with the sixth possible implementation of the second aspect, in a ninth possible implementation manner of the second aspect, the error extractor is specifically configured to: the first error multiplied by the first factor to obtain the first a control coefficient, the second error is multiplied by a second factor to obtain a second correction error, and the second correction error is multiplied by a fourth factor to obtain a second control coefficient, wherein the first factor and the second The factor is a preset value, and the fourth factor is a value that varies with a peak-to-average ratio of the digital signal; the error control coefficient is obtained according to the first control coefficient and the second control coefficient.

In conjunction with the ninth possible implementation of the second aspect, the tenth possible aspect of the second aspect In an implementation manner, the fourth factor increases as the peak-to-average ratio of the digital signal decreases.

In conjunction with the seventh possible implementation of the second aspect, in an eleventh possible implementation manner of the second aspect, the error extractor is specifically configured to: use the first control coefficient and the second control The coefficients are respectively subjected to loop filtering to obtain a filtered first control coefficient and a filtered second control coefficient, and the filtered first control coefficient and the filtered second control coefficient are added or multiplied. The error control coefficient is obtained.

In conjunction with the seventh possible implementation of the second aspect, in a twelfth possible implementation of the second aspect, the error extractor is specifically configured to: use the first control coefficient and the second control The coefficients are added or multiplied to obtain the error control coefficients.

In conjunction with the twelfth possible implementation of the second aspect, in the thirteenth possible implementation of the second aspect, the control voltage generator further includes: a loop filter, a numerically controlled oscillator, and a low pass filter The loop filter is configured to receive the error control coefficient from the error extractor, perform loop filtering on the error control coefficient, and send the filtered error control coefficient to the numerically controlled oscillator; The numerical control oscillator is configured to receive the filtered error control coefficient from the loop filter, generate a control signal according to the filtered error control coefficient, and send the control signal to the low pass filter The low pass filter is configured to receive the control signal from the numerically controlled oscillator, obtain the second control voltage according to the control signal, and send the second control voltage to the voltage control Gain amplifier.

In the embodiment of the present invention, by introducing an average power detection method of N subcarriers, the average power of the N subcarrier signals can be accurately obtained, and the influence of the CW mutation is reduced, so that the power stability of each subcarrier signal received in the digital receiver is improved. , reducing the fluctuation in power, is conducive to demodulation; and combining the second power of the measured digital signal with the average power of the N subcarriers, avoiding the use of measuring the average power of the N subcarriers alone, occurs because the influence of CW is not considered The estimated peak power of the digital signal is too small, resulting in a situation where the signal power entering the ADC exceeds the dynamic range.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art description will be briefly described below, obviously, The drawings in the following description are only some of the embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive labor.

1 is a system architecture diagram of an embodiment of the present invention;

Figure 2 (a) Schematic diagram of CW interference superposition in a single carrier system;

Figure 2 (b) Schematic diagram of CW interference superposition in a multi-carrier system;

3 is a flow chart of a method according to an embodiment of the present invention;

4 is a schematic diagram showing a second threshold setting according to another embodiment of the present invention;

Figure 5 is a structural diagram of a device according to an embodiment of the present invention;

Figure 6 is a structural diagram of a device according to another embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

In the following description, for purposes of illustration and description, reference However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments without these specific details. In other instances, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the invention.

When the embodiments of the present invention refer to ordinal numbers such as "first", "second" and the like, unless they are intended to express the order according to the context, it should be understood as merely distinguishing.

In the microwave transmission system, the microwave will undergo power changes during the spatial transmission process. For example, sudden rain, fogging, etc. will cause the microwave transmission channel to produce rapid fading, which is reflected in the signal is the receiving power of the receiving end is fast. The reduction. The AGC technology is a method in which the amplitude of the input signal of the ADC is substantially constant or varies within a small range by adjusting the gain of the controllable gain amplifier when the amplitude of the input signal varies greatly. Because the receiver circuit has a positive For normal working range, if the input signal is too small, the signal may be overwhelmed by noise. If the input signal is too large, the circuit may be overloaded or saturated, and the circuit may not work properly.

However, in the existing AGC technology, the multi-carrier data entering the AGC module does not distinguish between the useful signal and the interference signal, and the average power of the useful signal cannot be accurately obtained, so that the power stability of each sub-carrier signal received in the digital receiver is poor. It is not conducive to demodulation; and the existing AGC technology sets a fixed target threshold and detects the average power of the data entering the AGC module. The gain of the gain amplifier is determined by comparing the average power with the target threshold. The setting of the threshold should consider the case where the peak-to-average ratio of the data is the highest. Therefore, when the peak-to-average ratio is low, the existing AGC technology cannot fully utilize the dynamic range of the ADC, which causes waste of the dynamic range of the ADC.

In order to facilitate the understanding of those skilled in the art, the present invention describes the specific implementation process of the technical solution provided by the present invention through the following embodiments.

In the embodiment of the present invention, a system architecture diagram is provided as shown in FIG. 1 for applying the method provided by the embodiment of the present invention. The workflow of the system architecture is as follows:

First, the digital modulation and demodulation chip performs framing, encoding, and Quadrature Amplitude Modulation (QAM) mapping on the data information of the N subcarriers. Thereafter, each subcarrier is spectrally shifted according to the actual spectrum allocation interval and then combined into a whole. The combined data information is input to an analog to digital converter (DAC) to convert the digital signal into an analog signal. The signal is sent out through the transmitting antenna after analog modulation, frequency conversion, and amplification processing.

Second, the transmitted signal is transmitted over a distance and received by the receiving antenna into the receiving channel. During transmission, there will be interference, such as CW interference, the signal power will change. The receiving analog channel first converts the input signal (single carrier signal or multi-carrier signal as a whole) to the frequency point that the digital modem can receive. Filtering, and then transmitting the filtered signal to the VGA, wherein the CW interference may be formed by electromagnetic waves transmitted by other devices, at a certain fixed frequency, and the N subcarriers sent by the digital modem chip are not in the same On the frequency.

Third, the VGA is a voltage control device gain size module. The VGA has two inputs, one input is a signal input, and the other input is a control voltage input, and one output outputs a received signal after being amplified by the VGA to the ADC. The signal after ADC conversion will have a The part is divided into the AGC module, and the other part is subjected to subsequent reception processing.

Fourth, the AGC module can obtain the power information of the current signal, send the control voltage to the VGA, and control the gain intensity of the VGA, so that the amplitude of the signal of the input ADC is within a suitable range with a high probability to ensure the normal operation of the ADC. .

It can be understood that the system architecture diagram shown in FIG. 1 is a possible application scenario of the embodiment of the present invention, and the embodiment of the present invention may also be applied to other scenarios, which is not limited by the disclosure.

It should be noted that the CW interference is a signal at a certain fixed frequency in frequency, and is filtered by the filter in a single carrier system, as shown in Fig. 2(a), in the multi-carrier system, due to The subcarrier signals have a frequency interval between each other, and the frequency band of the filter is required to be larger, which is likely to preserve the CW interference, as shown in Fig. 2(b). Therefore, the CW interference cannot be ignored in the multicarrier system. Impact.

An embodiment of the present invention provides an automatic control gain method. As shown in FIG. 3, the method may include:

301. Receive an analog signal and a first control voltage, perform a gain on the analog signal according to the first control voltage, and perform analog-to-digital conversion on the analog signal after the gain to obtain a digital signal.

302. Separating N subcarrier signals from the digital signal, where the digital signal includes N subcarrier signals, and N is a positive integer.

The method for separating the N subcarrier signals from the digital signal may be: dividing the digital signal into N channels, each of the digital signals being the same, and moving the Kth subcarrier signal of the Kth digital signal to the zero by the spectrum shifting technique. The frequency is further matched and filtered to separate the Kth subcarrier signal, where K is a positive integer not greater than N.

303. Measure a sum of average powers of the N subcarrier signals in the first time period to obtain a first power.

Specifically, the ADC samples the N subcarrier signals, and if the number of sampling points in the first time period is L, the sum of the average powers of the N subcarrier signals in the first time period is:

Where data _n represents the value of the nth sample point.

304. Measure the power of each sample point of the digital signal in the second period, according to each sample The power of the point gives the second power.

305. Obtain a first error according to the first power and the first threshold, obtain a second error according to the second power and the second threshold, and obtain an error control coefficient according to the first error and the second error.

The first threshold is used to extract the power error of the N subcarrier signals, and the second threshold is used to extract the peak power error of the digital signal. The first threshold is a preset value. Preferably, the first time period and the second time period are equal.

Specifically, the first error and the second error are obtained by subtracting the first power from the first threshold to obtain a first error, and subtracting the second power from the second threshold to obtain a second error. Optionally, as another embodiment, the first error and the second error may be obtained by performing a logarithm operation on the ratio of the first threshold and the first power to obtain a first error; The ratio of the two powers is logarithmically calculated to obtain a second error.

306. Generate a second control voltage according to the error control coefficient, where the second control voltage is used to control a gain of the analog signal.

Optionally, as another embodiment, the power of each sampling point of the digital signal in the second time period is measured, and the average power of the digital signal sampling point whose power is greater than the second threshold is measured as the second power.

In the embodiment of the present invention, the digital signal sampling points whose power exceeds the second threshold in the second time period are counted, and the power of the digital signal sampling point that satisfies the requirement is averaged, and the second power is reduced as the second power. Jitter, improve stability.

Wherein, the error control coefficient is obtained by multiplying the first error by the first factor to obtain the first control coefficient, and the second error is multiplied by the second factor to obtain the second control coefficient; according to the first control coefficient and the second control coefficient Obtaining an error control coefficient, wherein the first factor and the second factor are Pre-set values.

It should be understood that the first error is the power error of the N subcarrier signals, and the second error is the peak power error of the digital signal. The first factor and the second factor are both numbers far less than one, which can reduce the intensity of the signal change and improve the system. The stability of the operation, and the first factor and the second factor can set several different sets of values according to the requirements of the system, wherein the system requirements are mainly the tracking speed of the power change, the degree of power jitter, and the like.

Optionally, as another embodiment, measuring the power of each sampling point of the digital signal in the second time period, calculating the peak power of the digital signal in the second time period as the second power; calculating the digital signal in the second time period The average power in the internal power is obtained according to the second power and the average power, and the peak-to-average ratio of the digital signal is obtained. According to the peak-to-average ratio of the digital signal, the second threshold is obtained, wherein the peak ratio of the digital signal is larger, and the second threshold is smaller.

It should be understood that the formula for calculating the peak-to-average ratio is as follows:

PAR=P_peak/P_average

Among them, P_peak is the peak power, and P_average is the average power in milliwatts or watts.

It should be understood that decibel (dB) is a relative ratio, and the subtraction between two quantities in dB is equivalent to the division between actual quantities (for example, milliwatts), therefore, in dB. , the peak-to-average ratio calculation formula can be written as:

PAR=P_peak-P_average

The following are all described in dB, where the second threshold is the target mean of the digital signal, and the difference between the sum of the second threshold and the peak sum of the digital signal and the dynamic range of the ADC is used as a protection threshold for Ensure that the peak power does not exceed the dynamic range of the ADC. It can be set according to the specific conditions of the digital signal. In the digital signal, when the CW power is greater than the power of the subcarrier signal, the protection threshold can be appropriately small because the power of the CW is relatively stable. Some, conversely, when the CW power is less than the power of the subcarrier signal, the protection threshold may be appropriately larger.

It should be understood that since the digital signal contains N subcarrier signals, the modulation format adopted by each subcarrier signal may be different, and the peak-to-average ratio of signals using different modulation formats is also different, and the order of the modulation format is higher, the peak The ratio is greater. Among them, CW can be understood as a sine wave or a cosine wave, and the peak-to-average ratio is about 3 dB, which is smaller than the peak-to-average ratio of Quadrature Phase Shift Keying (QPSK).

It should be noted that the sum of the second threshold and the digital signal peak is smaller than the dynamic range of the ADC. The dynamic range of the ADC refers to the difference between the maximum power and the minimum power acceptable to the ADC. Specifically, taking the dynamic range of the ADC as 19dB, the protection threshold is assumed to be 3dB. If the peak-to-average ratio of the digital signal is 6dB, the second threshold at this time can be set to 10dB. If the peak-to-average ratio of the digital signal is 12dB, then The second threshold at this time can be set to 4 dB; when the power of the CW is greater than the power of the subcarrier signal, the peak-to-average ratio of the digital signal is the peak-to-average ratio of the CW, which is about 3 dB. Since the power of the CW is relatively stable, the protection threshold can be reduced. Small, assuming a reduction of 1 dB, the second threshold can be set to 15 dB.

In summary, the value of the second threshold is related to the peak-to-average ratio of the digital signal, and the second threshold expression is:

Second_th=K*PAR+B

Among them, K and B are preset values according to the dynamic range of the ADC and the protection threshold.

Still taking the dynamic range of the ADC as 19dB, if the protection threshold is not considered, and the protection threshold is fixed at 3dB, the expression of the second threshold can be:

Second_th=16-PAR

Where K is -1 and B is 16 dB. At this time, since the second threshold is the target mean of the digital signal, the peak power of the digital signal can reach about 16 dB, which can fully utilize the dynamic range of the ADC, and has 3 dB of protection, which does not exceed the dynamic range of the ADC, resulting in Signal distortion problem.

If the protection threshold can be reduced when the CW power is greater than the subcarrier signal power, the second threshold expression may specifically be:

As shown in FIG. 4, the abscissa represents the peak-to-average ratio, and the ordinate represents the second threshold. When the digital signal peak-to-average ratio is 12 dB, the second threshold is 0 dB; when the digital signal peak-to-average ratio is 3 dB, the second threshold is 15dB.

It should be noted that when the peak-to-average ratio of the digital signal is 12 dB, the peak power of the digital signal can only reach about 12 dB, and the utilization of the dynamic range of the ADC is not as good as the fixed protection threshold, but when the peak-to-average ratio of the digital signal is 3 dB, The peak power of the digital signal can reach about 18dB. The way in which the dynamic range of the ADC is better than the fixed protection threshold. Moreover, when the peak-to-average ratio of the digital signal is 3dB, the power of the CW is much larger than the power of the subcarrier signal, and the protection threshold of 1dB can also ensure that the dynamic range of the ADC does not appear, resulting in signal distortion.

In the prior art, the second threshold is based on the maximum peak-to-average ratio of the digital signal, assuming that the ADC dynamic range is still 19 dB, the peak-to-average ratio is between 4 dB and 12 dB, and the protection threshold is still set to 3 dB. The second threshold is set to 19dB-12dB-3dB=4dB. When the digital signal peak-to-average ratio is 12dB, the dynamic range of the ADC can be fully utilized, but when the digital signal peak-to-average ratio is 4dB, due to the second The threshold is the target mean of the digital signal, and the peak power of the digital signal is about 8dB. With 11dB as the protection threshold, the dynamic range of the ADC is wasted.

It should be understood that the second threshold expression of the embodiment of the present invention is not limited to the above two types, and may be set according to actual conditions, which is not limited by the present invention.

Optionally, as another embodiment, the obtaining the error control coefficient according to the first error and the second error specifically includes: multiplying the first error by the first factor, obtaining the first correction error, and multiplying the first correction error by a three factor, a first control coefficient is obtained, and a second error is multiplied by a second factor to obtain a second control coefficient; and an error control coefficient is obtained according to the first control coefficient and the second control coefficient, wherein the first factor and the second factor are The pre-set value, the third factor is the value that varies with the peak-to-average ratio.

Among them, the third factor will decrease as the peak-to-average ratio of the digital signal decreases. In the case where the modulation format of the digital signal remains unchanged, if the peak-to-average ratio of the digital signal is reduced, the power of the CW will be It will rise, that is, the influence of CW will increase. Therefore, the ratio of the first error is reduced, and it is necessary to multiply by the third factor.

Optionally, as another embodiment, the obtaining the error control coefficient according to the first error and the second error specifically includes: multiplying the first error by the first factor, obtaining the first control coefficient, and multiplying the second error by the second a second correction error is obtained by multiplying the second correction error by a fourth correction factor; and an error control coefficient is obtained according to the first control coefficient and the second control coefficient, wherein the first factor and the second factor are The pre-set value, the fourth factor is the value that varies with the peak-to-average ratio.

Among them, the fourth factor will increase as the peak-to-average ratio of the digital signal decreases.

Optionally, as another embodiment, the specific manner of obtaining the error control coefficient according to the first control coefficient and the second control coefficient is: adding or multiplying the first control coefficient and the second control coefficient to obtain an error a control coefficient; the specific manner of generating the second control voltage according to the error control coefficient is: performing loop filtering (LPF), numerical control oscillation, and low-pass filtering processing on the error control coefficient to generate a second control voltage .

Optionally, the specific manner of obtaining the error control coefficient according to the first control coefficient and the second control coefficient may further be: performing loop filtering on the first control coefficient and the second control coefficient, respectively, to obtain the filtered first The control coefficient and the filtered second control coefficient add or multiply the filtered first control coefficient and the filtered second control coefficient to obtain an error control coefficient.

The error control coefficient is subjected to numerical control oscillation and low-pass filtering processing to generate a second control voltage.

Specifically, the loop filtering can filter the jitter of the control coefficient, and the time domain expression of the loop filtering is:

Lpf_out(n)=lpf_out(n-1)+err(n)*kp+err(n-1)*(kp-ki)

Where lpf_out(n-1) represents the output of the n-1th loop filter, err(n-1) represents the error control coefficient obtained at the n-1th time, kp is the scale factor, ki is the integral factor, and modulation Two factors can obtain a stable output, and loop filtering can filter out the low-probability abrupt signal and enhance the stability of the system.

The numerical control oscillation of the error control coefficient can generate a control signal that reflects the voltage value by the clock duty ratio, and controls the voltage setting of the VGA. When the error control coefficient is greater than 0, the description The current power value is smaller than the target power value, and the voltage needs to be increased, and vice versa. Preferably, the control signal is a Pulse Width Modulation (PWM) signal.

The low-pass filtering process is performed on the control signal, and the control voltage represented by the duty ratio in the control signal can be converted into the actual control voltage to complete the control voltage input of the VGA, and finally the AGC control function is completed. Taking the output pin voltage of the digital modulation and demodulation chip as 1V as an example, since the duty ratio of the control signal ranges from 0% to 100%, when the control voltage required to be output is 0.45V, the output duty ratio is 45%. The control signal is subjected to low-pass filtering, and the output control voltage is 0.45V.

An embodiment of the present invention provides an automatic control gain device, as shown in FIG. 5, including: a voltage control gain amplifier 510, an analog to digital converter 520, a subcarrier power detector 530, a digital signal detector 540, and an error extractor 550. Control voltage generator 560,

The voltage control gain amplifier 510 is configured to receive the analog signal and the first control voltage, perform gain on the analog signal according to the first control voltage, and send the analog signal after the gain to the analog to digital converter 520.

The analog-to-digital converter 520 is configured to receive the analog signal after the gain from the voltage control gain amplifier 510, perform analog-to-digital conversion on the analog signal after the gain, obtain a digital signal, and send the digital signal to the subcarrier power detector 530 and the digital signal. Detector 540.

The subcarrier power detector 530 is configured to receive a digital signal from the analog to digital converter 520, separate N subcarrier signals from the digital signal, and calculate a sum of average powers of the N subcarrier signals in the first time period to obtain a first power. The first power is sent to the error extractor 550, where N is a positive integer.

Optionally, as another embodiment, the subcarrier power detector 530 is specifically configured to: divide the digital signal into N channels, each of the digital signals are the same, and pass the Kth subcarrier signal of the Kth digital signal to the spectrum shifting technology. Move to zero frequency, and then perform matched filtering to separate the Kth subcarrier signal, where K is a positive integer not greater than N.

Specifically, the analog-to-digital converter 530 samples the N subcarrier signals, and if the number of sampling points in the first time period is L, the sum of the average powers of the N subcarrier signals in the first time period is:

Where data _n represents the value of the nth sample point.

The digital signal detector 540 is configured to receive a digital signal from the analog-to-digital converter 520, measure the power of each sampling point of the digital signal in the second time period, and obtain a second power according to the power of each sampling point, and obtain the second power. It is sent to the error extractor 550.

Preferably, the first time period and the second time period are equal.

Optionally, the digital signal detector 540 is specifically configured to: measure an average power of the digital signal sampling point whose power is greater than the second threshold as the second power.

In the embodiment of the present invention, the digital signal detector 540 counts the digital signal sampling points whose power exceeds the second threshold in the second time period, and calculates the power average value of the digital signal sampling point that meets the requirement as the second power. It can reduce the jitter of the second power and improve the stability.

The error extractor 550 is configured to receive the first power from the subcarrier power detector 530, receive the second power from the digital signal detector 540, and obtain a first error according to the first power and the first threshold, according to the second power and the first The second threshold obtains a second error, and according to the first error and the second error, an error control coefficient is obtained, and the error control coefficient is sent to the control voltage generator 560.

The first threshold is used to extract the power error of the N subcarrier signals, and the second threshold is used to extract the second power error of the digital signal, and the first threshold is a preset value.

Optionally, the error extractor 550 is specifically configured to: subtract the first power from the first threshold to obtain a first error; subtract the second power from the second threshold to obtain a second error; or use the first threshold and the first power The ratio is logarithmically operated to obtain a first error; the ratio of the second threshold to the second power is logarithmically computed to obtain a second error.

Optionally, as another embodiment, the error extractor 550 is specifically configured to: multiply the first error by the first factor to obtain the first control coefficient, and multiply the second error by the second factor to obtain the second control coefficient; The first control coefficient and the second control coefficient obtain an error control coefficient.

It should be understood that the first error is the power error of the N subcarrier signals, and the second error is the peak power error of the digital signal. The first factor and the second factor are both numbers far less than one, which can reduce the intensity of the signal change and improve the system. The stability of the operation, and the first factor and the second factor can set several different sets of values according to the requirements of the system, wherein the system requirements are mainly the chasing of the power change Trace speed, power jitter level, etc.

The control voltage generator 560 is configured to receive an error control coefficient from the error extractor 550, obtain a second control voltage according to the error control coefficient, and send the second control voltage to the voltage control gain amplifier 510, wherein the second control voltage is used for control The gain on the analog signal.

In the embodiment of the present invention, by introducing an average power detection method of N subcarriers, the average power of the N subcarrier signals can be accurately obtained, and the influence of the CW mutation is reduced, so that the power stability of each subcarrier signal received in the digital receiver is improved. , reducing the fluctuation in power, is conducive to demodulation; and combining the second power of the measured digital signal with the average power of the N subcarriers, avoiding the use of measuring the average power of the N subcarriers alone, occurs because the influence of CW is not considered The peak power of the estimated digital signal is too small, resulting in a situation where the signal power entering the analog-to-digital converter 520 exceeds the dynamic range.

Optionally, as another embodiment, as shown in FIG. 6, the digital signal detector 540 further includes: a peak power detector 541, an average power detector 542 and a peak-to-average ratio calculator 543;

The peak power detector 541 is configured to detect the peak power of the digital signal in the second time period, and send the peak power to the peak-to-average ratio calculator 543;

The average power detector 542 is configured to detect the average power of the digital signal in the second time period, and send the average power to the peak-to-average ratio calculator 543;

The peak-to-average ratio calculator 543 is configured to receive the peak power from the peak power detector 541, receive the average power from the average power detector 542, calculate the peak-to-average ratio of the digital signal in the second period, and send the peak-to-average ratio of the digital signal to Error extractor 550.

Optionally, as another embodiment, the error extractor 550 is further configured to receive a peak-to-average ratio of the digital signal from the peak-to-average ratio calculator 543, and obtain a second threshold according to a peak-to-average ratio of the digital signal, where the digital signal peaks are averaged The larger the ratio, the smaller the second threshold.

The calculation of the peak-to-average ratio of the digital signal and the specific setting of the second threshold have been described in detail in the foregoing embodiments, and the embodiments of the present invention are not described herein.

The second threshold of the embodiment of the present invention changes with the change of the peak-to-average ratio of the digital signal, and the dynamic range of the analog-to-digital converter 520 can be more fully utilized compared with the fixed second threshold, due to entering the modulus The signal to noise ratio of the signal of converter 520 is proportional to the effective number of bits of analog to digital converter 520, and the more fully the dynamic range of analog to digital converter 520 is utilized, analog to digital converter 520 The higher the effective number of bits, the embodiment of the invention allows the input signal to have a higher signal to noise ratio.

Optionally, as another embodiment, the error extractor 550 is specifically configured to: multiply the first error by the first factor to obtain a first correction error, and multiply the first correction error by a third factor to obtain a first control coefficient, Multiplying the second error by the second factor to obtain a second control coefficient, wherein the first factor and the second factor are preset values, and the third factor is a value that varies with the peak-to-average ratio; according to the first control coefficient and The second control coefficient gives the error control coefficient.

It should be understood that the first error is the power error of the N subcarrier signals, the second error is the peak power error of the digital signal, and the third factor varies with the peak-to-average ratio of the digital signal; both the first factor and the second factor are It is a number far less than 1, which can reduce the intensity of signal change and improve the stability of the system operation, and the first factor and the second factor can set several different sets of values according to the requirements of the system, wherein the system requirements are mainly power changes. Tracking speed, power jitter level, etc.

Among them, the third factor will decrease as the peak-to-average ratio of the digital signal decreases. Wherein, if the modulation format of the digital signal remains unchanged, if the peak-to-average ratio of the digital signal decreases, the power of the CW will increase, that is, the influence of the CW will increase, and therefore, the first error The ratio is less important and needs to be adjusted by the third factor.

Optionally, as another embodiment, the error extractor 550 is specifically configured to: multiply the first error by the first factor to obtain the first control coefficient, and multiply the second error by the second factor to obtain the second correction error. The second correction factor is multiplied by the fourth factor to obtain a second control coefficient, wherein the first factor and the second factor are preset values, and the fourth factor is a value that varies with the peak-to-average ratio of the digital signal; according to the first control The coefficient and the second control coefficient result in an error control coefficient.

Optionally, as another embodiment, the error extractor 550 is specifically configured to: perform loop filtering on the first control coefficient and the second control coefficient, respectively, to obtain the filtered first control coefficient and the filtered second control coefficient. And adding or multiplying the filtered first control coefficient and the filtered second control coefficient to obtain an error control coefficient.

Optionally, the error extractor 550 is specifically configured to: add or multiply the first control coefficient and the second control coefficient to obtain an error control coefficient.

The control voltage generator 560 further includes a loop filter 561, a numerically controlled oscillator 562, and a low pass filter 563.

The loop filter 561 is configured to receive an error control coefficient from the error extractor 550, perform loop filtering on the error control coefficient, and send the filtered error control coefficient to the numerically controlled oscillator 562.

The numerically controlled oscillator 562 is configured to receive the filtered error control coefficient from the loop filter 561, generate a control signal according to the filtered error control coefficient, and send the control signal to the low pass filter 563.

The low pass filter 563 is configured to receive a control signal from the numerically controlled oscillator 562, obtain a second control voltage according to the control signal, and send the second control voltage to the voltage control gain amplifier 510.

The loop filter 561 can filter out the low-probability abrupt signal and enhance the stability of the system. The numerical control oscillator 562 can generate a control signal that reflects the voltage value by the clock duty according to the filtered error control coefficient, and controls the VGA. Voltage setting. When the error control coefficient is greater than 0, it indicates that the current power value is smaller than the target power value, and the voltage needs to be increased, and vice versa. Preferably, the control signal is a PWM signal.

The low-pass filter 563 can convert the control voltage represented by the duty ratio in the control signal into an actual control voltage, complete the control voltage input of the VGA, and finally complete the function of the AGC control. Taking the output pin voltage of the digital modulation and demodulation chip as 1V as an example, since the duty ratio of the control signal ranges from 0% to 100%, when the control voltage required to be output is 0.45V, the output duty ratio is 45%. The control signal is subjected to low-pass filtering, and the output control voltage is 0.45V.

The above is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention. It should be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the appended claims.

Claims

An automatic gain control method, comprising:

Receiving an analog signal and a first control voltage, performing a gain on the analog signal according to the first control voltage, and performing analog-to-digital conversion on the analog signal after the gain to obtain a digital signal;

Separating N subcarrier signals from the digital signal, wherein N is a positive integer;

Measure a sum of average powers of the N subcarrier signals in a first time period to obtain a first power;

Measuring a power of each sampling point of the digital signal in a second time period, and obtaining a second power according to the power of each sampling point;

Obtaining a first error according to the first power and the first threshold, and obtaining a second error according to the second power and the second threshold, and obtaining an error control coefficient according to the first error and the second error;

A second control voltage is generated based on the error control coefficient, wherein the second control voltage is used to control a gain of the analog signal.
The method according to claim 1, wherein the separating the N subcarrier signals from the digital signal comprises:

Dividing the digital signal into N channels, each of the digital signals is the same, and moving the Kth subcarrier signal of the Kth digital signal to a zero frequency by a spectrum shifting technique, and then performing matched filtering to separate the Kth subcarrier signal. Where K is a positive integer not greater than N.
The method of claim 1 wherein

The obtaining the first error according to the first power and the first threshold specifically includes: subtracting the first power from the first threshold, to obtain the first error;

The obtaining the second error according to the second power and the second threshold specifically includes: subtracting the second power from the second threshold to obtain the second error.
The method according to any one of claims 1 to 3, wherein the obtaining the second power according to the power of each sampling point comprises:

The average power of the digital signal sampling point whose power is greater than the second threshold is measured as the second power.
The method of claim 4 wherein said first error is based And the second error, the error control coefficient specifically includes:

The first error is multiplied by the first factor to obtain a first control coefficient, and the second error is multiplied by the second factor to obtain a second control coefficient, wherein the first factor and the second factor are preset Fixed value

And obtaining the error control coefficient according to the first control coefficient and the second control coefficient.
A method according to any one of claims 1 to 3, characterized in that

The obtaining the second power according to the power of each sampling point specifically includes: calculating a peak power of the sampling point of the digital signal as the second power;

After obtaining the second power, the method further includes: measuring an average power of the digital signal in the second time period, and obtaining a peak-to-average ratio of the digital signal according to the second power and the average power, according to The digital signal peak-to-average ratio is obtained, and the second threshold is obtained, wherein the digital signal peak-to-average ratio is larger, and the second threshold is smaller.
The method according to claim 6, wherein the obtaining the error control coefficient according to the first error and the second error comprises:

The first error is multiplied by the first factor to obtain a first correction error, the first correction error is multiplied by a third factor to obtain a first control coefficient, and the second error is multiplied by a second factor to obtain a second control a coefficient, wherein the first factor and the second factor are preset values, and the third factor is a value that varies with a peak-to-average ratio of the digital signal;

And obtaining the error control coefficient according to the first control coefficient and the second control coefficient.
The method of claim 7 wherein said third factor decreases as said peak ratio of said digital signal decreases.
The method according to claim 6, wherein the obtaining the error control coefficient according to the first error and the second error comprises:

The first error is multiplied by the first factor to obtain a first control coefficient, the second error is multiplied by the second factor to obtain a second correction error, and the second correction error is multiplied by a fourth factor to obtain a second control a coefficient, wherein the first factor and the second factor are preset values, and the fourth factor is a value that varies with a peak-to-average ratio of the digital signal;

And obtaining the error control coefficient according to the first control coefficient and the second control coefficient.
The method of claim 9 wherein said fourth factor follows The digital signal peak-to-average ratio decreases and increases.
The method of claim 7 wherein:

The obtaining the error control coefficient according to the first control coefficient and the second control coefficient specifically includes: adding or multiplying the first control coefficient and the second control coefficient to obtain the error control coefficient ;

The generating the second control voltage according to the error control coefficient specifically includes: performing loop filtering, numerical control oscillation, and low-pass filtering processing on the error control coefficient to generate the second control voltage.
The method of claim 7 wherein:

The obtaining the error control coefficient according to the first control coefficient and the second control coefficient specifically includes: performing loop filtering on the first control coefficient and the second control coefficient, respectively, to obtain a filtered first Controlling the coefficient and the filtered second control coefficient, adding or multiplying the filtered first control coefficient and the filtered second control coefficient to obtain the error control coefficient;

The generating the second control voltage according to the error control coefficient specifically includes: performing numerical control oscillation and low-pass filtering processing on the error control coefficient to generate the second control voltage.
An automatic gain control device, comprising: a voltage control gain amplifier, an analog to digital converter, a subcarrier power detector, a digital signal detector, an error extractor, a control voltage generator,

The voltage control gain amplifier is configured to receive an analog signal and a first control voltage, perform a gain on the analog signal according to the first control voltage, and send the analog signal after the gain to the analog to digital converter;

The analog-to-digital converter is configured to receive the analog signal after the gain from the voltage control gain amplifier, perform analog-to-digital conversion on the analog signal after the gain, obtain a digital signal, and send the digital signal to the Determining a subcarrier power detector and the digital signal detector;

The subcarrier power detector is configured to receive the digital signal from the analog to digital converter, separate N subcarrier signals from the digital signal, and measure an average of the N subcarrier signals in a first time period a sum of powers, a first power is obtained, and the first power is sent to the error extractor, where N is a positive integer;

The digital signal detector is configured to receive the digital signal from the analog to digital converter, and measure power of each sampling point of the digital signal in a second time period, according to the power of each sampling point, a second power, the second power is sent to the error extractor;

The error extractor is configured to receive the first power from the subcarrier power detector, receive the second power from the digital signal detector, and obtain a first according to the first power and the first threshold An error, according to the second power and the second threshold, obtaining a second error, according to the first error and the second error, obtaining an error control coefficient, and sending the error control coefficient to the control voltage Device

The control voltage generator is configured to receive the error control coefficient from the error extractor, obtain a second control voltage according to the error control coefficient, and send the second control voltage to the voltage control gain amplifier, Wherein the second control voltage is used to control a gain of the analog signal.
The device according to claim 13, wherein the subcarrier power detector is specifically configured to:

Dividing the digital signal into N channels, each of the digital signals is the same, and moving the Kth subcarrier signal of the Kth digital signal to a zero frequency by a spectrum shifting technique, and then performing matched filtering to separate the Kth subcarrier signal. Where K is a positive integer not greater than N.
The device according to claim 13, wherein the error extractor is specifically configured to:

The first threshold is subtracted from the first power to obtain the first error; the second threshold is subtracted from the second power to obtain the second error.
The device according to any one of claims 13 to 15, wherein the digital signal detector is specifically configured to:

The average power of the digital signal sampling point whose power is greater than the second threshold is measured as the second power.
The device according to claim 16, wherein the error extractor is specifically configured to:

Multiplying the first error by a first factor to obtain a first control coefficient, the second error multiplied by a second factor, to obtain a second control coefficient, wherein the first factor and the second factor are pre- First set value;

And obtaining the error control coefficient according to the first control coefficient and the second control coefficient.
The apparatus according to any one of claims 13 to 15, wherein the digital signal detector further comprises: a peak power detector, an average power detector, and a peak-to-average ratio calculator;

The peak power detector is configured to detect a peak power of the digital signal in a second time period, and send the peak power to the peak-to-average ratio calculator;

The average power detector is configured to detect an average power of the digital signal in a second time period, and send the average power to the peak-to-average ratio calculator;

The peak-to-average ratio calculator for receiving the peak power from the peak power detector, receiving the average power from the average power detector, and calculating a digital signal peak in a second time period of the digital signal The digital signal peak-to-average ratio is sent to the error extractor.
The device according to claim 18, wherein the error extractor is further configured to receive a peak-to-average ratio of the digital signal from the peak-to-average ratio calculator, and obtain a peak according to a peak-to-average ratio of the digital signal The second threshold, wherein the digital signal peak-to-average ratio is larger, and the second threshold is smaller.
The device according to claim 19, wherein the error extractor is specifically configured to:

The first error is multiplied by the first factor to obtain a first correction error, the first correction error is multiplied by a third factor to obtain a first control coefficient, and the second error is multiplied by a second factor to obtain a second control a coefficient, wherein the first factor and the second factor are preset values, and the third factor is a value that varies with a peak-to-average ratio of the digital signal;

And obtaining the error control coefficient according to the first control coefficient and the second control coefficient.
The apparatus according to claim 20, wherein said third factor decreases as the peak-to-average ratio of said digital signal decreases.
The device according to claim 19, wherein the error extractor is specifically configured to:

The first error is multiplied by the first factor to obtain a first control coefficient, the second error is multiplied by the second factor to obtain a second correction error, and the second correction error is multiplied by a fourth factor to obtain a second control a coefficient, wherein the first factor and the second factor are preset values, The fourth factor is a value that varies with the peak-to-average ratio of the digital signal;

And obtaining the error control coefficient according to the first control coefficient and the second control coefficient.
The apparatus according to claim 22, wherein said fourth factor increases as said peak ratio of said digital signal decreases.
The device according to claim 20, wherein the error extractor is specifically configured to:

Performing loop filtering on the first control coefficient and the second control coefficient, respectively, to obtain a filtered first control coefficient and a filtered second control coefficient, and the filtered first control coefficient and the The filtered second control coefficients are added or multiplied to obtain the error control coefficients.
The device according to claim 20, wherein the error extractor is specifically configured to:

Adding or multiplying the first control coefficient and the second control coefficient to obtain the error control coefficient.
The apparatus according to claim 25, wherein said control voltage generator further comprises: a loop filter, a numerically controlled oscillator, a low pass filter,

The loop filter is configured to receive the error control coefficient from the error extractor, perform loop filtering on the error control coefficient, and send the filtered error control coefficient to the numerically controlled oscillator;

The numerical control oscillator is configured to receive the filtered error control coefficient from the loop filter, generate a control signal according to the filtered error control coefficient, and send the control signal to the low pass filter Device

The low pass filter is configured to receive the control signal from the numerically controlled oscillator, obtain the second control voltage according to the control signal, and send the second control voltage to the voltage control gain amplifier .