WO2014063577A1 - Feedback link and method for implementing same - Google Patents

Abstract

Disclosed are a feedback link and a method for implementing same. The present invention relates to communication field and can not rely on the ADC device performance to achieve an accurate sampling of the radio frequency output signal. The detailed solution comprises: the feedback link is applied to a radio frequency amplification circuit; the radio frequency amplification circuit receives an initial primary signal, and then exports a first output signal with primary and stray signals after the radio frequency amplification circuit has amplified. The feedback link comprises a first power regulator, a coupler, a first analog-digital converter ADC and a digital signal process DSP. An input end of the first power regulator is connected to an output end of the coupler, an input end of the coupler is connected to an output end of the radio frequency amplification circuit, an input end of the first ADC is connected to an output end of the first power regulator, an output end of the first ADC is connected to an input end of the DSP, and an output end of the DSP is connected to an input end of the radio frequency amplification circuit. The present invention is applied to the implementation process of the feedback link.

Description

 The present invention claims the priority of the Chinese patent application filed on October 24, 2012, filed on the Chinese Patent Office, Application No. 201210410104.0, entitled "A Feedback Link and Its Implementation Method" The entire contents of which are incorporated herein by reference. Technical field

 The present invention relates to the field of communications, and in particular, to a feedback link and an implementation method thereof. Background technique

 In the communication system, the radio frequency amplification circuit is used to increase the transmission power of the radio frequency module. In order to save energy and reduce consumption, the power amplifier generally operates in a non-linear region. Therefore, when amplifying the linear modulation signal, linear amplification of the radio frequency signal cannot be performed, which may result in partial main The signal does not reach the maximum power and produces severe distortion. In order to reduce the distortion of the signal, digital pre-distortion (DPD) technology can be used to perform real-time sampling on the output signal of the power amplifier, and the feedback signal obtained by the sample is compensated and corrected for the main signal. The circuit forms the feedback link of the RF amplifying circuit.

 In the feedback link, a part of the energy signal is coupled from the RF signal output from the RF amplifying circuit as a sample object, and then sampled by an analog to digital converter (ADC). In actual use, due to the limited dynamic range of the ADC, some of the main signals that cannot be linearly amplified after being amplified by the RF amplifying circuit will not be able to be obtained, so that the feedback signal obtained by the sample cannot accurately reflect the RF output. The main signal can not be effectively compensated by reference to the feedback signal.

 The prior art solution is to use a higher dynamic range ADC in the feedback link to increase the dynamic range of the ADC so that the lower power main signal can be sampled to improve the performance of the feedback link.

In the process of implementing the above feedback link, the inventors found that at least the prior art exists as Next problem: Due to technical conditions, the dynamic range of the ADC device is limited, and the high dynamic range ADC device is too expensive, and it is not used in the communication system. Therefore, how to improve the performance of the feedback circuit of the RF amplifying circuit has become an important issue in the technical field. Summary of the invention

 Embodiments of the present invention provide a feedback link and an implementation method thereof, which can achieve accurate sampling of an RF output signal without depending on the performance of the ADC device.

 A first aspect of the present invention provides a feedback link for use in a radio frequency amplifying circuit, the radio frequency amplifying circuit receiving an initial main signal, and outputting a main signal and a spurious signal after being amplified by the radio frequency amplifying circuit a first output signal, the feedback link includes: a coupler, a first analog-to-digital converter ADC, and a digital signal processor DSP, the feedback link further comprising: a first power adjuster;

 An input end of the first power regulator is connected to an output end of the coupler, an input end of the coupler is connected to an output end of the radio frequency amplifying circuit, and an input end of the first ADC and the first An output of the power amplifier is connected, an output end of the first ADC is connected to an input end of the DSP, and an output end of the DSP is connected to an input end of the radio frequency amplifying circuit;

 The coupler is configured to receive a first output signal of the radio frequency amplifying circuit, obtain a second output signal from the first output signal according to a coupling ratio configured in advance, and output the signal to the first power adjuster;

 The first power adjuster is configured to receive a second output signal output by the coupler, calculate a first power adjustment coefficient according to an average power of the main signal, and adjust the first power adjustment coefficient by using the first power adjustment coefficient Transmitting the power of the signal, and outputting the adjusted second output signal to the first ADC;

 The first ADC is configured to receive the adjusted second output signal, and convert the adjusted second output signal into a digital signal output to the DSP;

The DSP is configured to receive a digital signal output by the first ADC, and calculate a compensation signal according to the digital signal, and send the compensation signal to the radio frequency amplifying circuit, so that The radio frequency amplifying circuit performs power compensation on the initial main signal according to the compensation signal. With reference to the first aspect, in a possible implementation manner, the feedback link further includes: a second power regulator, a second ADC, and a band rejection filter;

 An input end of the band rejection filter is connected to an output end of the coupler, an input end of the second power adjuster is connected to an output end of the band rejection filter, and an output of the second power adjuster The terminal is connected to the input end of the second ADC, and the output end of the second ADC is connected to the input end of the DSP;

 The band rejection filter is configured to acquire a second output signal of the coupler, and filter the main signal from the second output signal to obtain a spurious signal;

 The second power adjuster is configured to receive the spurious signal, calculate a second power adjustment coefficient according to the power of the spurious signal, and adjust the power of the spurious signal by using the second adjustment coefficient, And outputting the adjusted spurious signal to the second ADC;

 The second ADC is configured to receive the adjusted spurious signal, convert the adjusted spurious signal into a digital spurious signal, and output the digital spurious signal to the DSP;

 The DSP is further configured to receive a digital spur signal output by the second ADC, and combine the digital signal output by the first ADC and the digital spur signal output by the second ADC into a digital feedback signal. The digital feedback signal calculates a compensation signal, and sends the compensation signal to the radio frequency amplifying circuit, so that the radio frequency amplifying circuit performs power compensation on the initial main signal according to the compensation signal.

 With reference to the first aspect and the foregoing possible implementation manner, in another possible implementation manner, the first power adjuster is specifically configured to:

Calculating a logarithm of a ratio of an expected average power of the main signal and an average power of the main signal output by the radio frequency amplifying circuit, and adding a result obtained by taking the logarithm to a minimum amplification factor of the first power adjuster to obtain a first power adjustment coefficient of the first power regulator, adjusting a power of the second output signal by using the first power adjustment coefficient, and outputting the adjusted second output signal to the first ADC. With reference to the first aspect and the foregoing possible implementation manner, in another possible implementation manner, the second power adjuster is specifically configured to:

 Taking a logarithm of the ratio of the input signal power required by the second ADC to the optimal signal-to-noise ratio and the power of the spurious signal output by the band rejection filter to obtain a second power adjustment coefficient of the second power adjuster And adjusting the power of the spurious signal by using the second adjustment coefficient, and outputting the adjusted spurious signal to the second ADC.

 With reference to the first aspect and the foregoing possible implementation manner, in another possible implementation manner, the first power adjuster and the second power adjuster comprise: a low noise power amplifier or an adjustable attenuator.

 According to a second aspect of the present invention, a feedback link implementation method is provided, which is applied to a radio frequency amplifying circuit, where the radio frequency amplifying circuit receives an initial main signal, and after the amplification processing of the radio frequency amplifying circuit, the output includes a main signal and a spurious The first output signal of the signal, including:

 Receiving a first output signal of the radio frequency amplifying circuit, and acquiring a second output signal from the first output signal according to a coupling ratio configured in advance;

 Calculating a first power adjustment coefficient according to an average power of the main signal, and adjusting a power of the second output signal by using the first power adjustment coefficient;

 Converting the adjusted second output signal into a digital signal;

 Calculating a compensation signal according to the digital signal, and transmitting the compensation signal to the RF amplifying circuit, so that the RF amplifying circuit performs power compensation on the initial main signal according to the compensation signal.

 With reference to the second aspect, in a possible implementation, the method further includes: filtering the main signal from the second output signal to obtain a spurious signal;

 Calculating a second power adjustment coefficient according to the power of the spurious signal, and adjusting a power of the spurious signal by using the second adjustment coefficient;

 Converting the adjusted spurious signal into a digital spurious signal;

Combining the digital signal and the digital spur signal into a digital feedback signal, according to the number The feedback signal calculates a compensation signal, and sends the compensation signal to the radio frequency amplifying circuit, so that the radio frequency amplifying circuit performs power compensation on the initial main signal according to the compensation signal.

 With reference to the second aspect and the foregoing possible implementation manner, in another possible implementation manner, the calculating, by the average power of the main signal, the first power adjustment coefficient, specifically:

 Comparing a ratio of an expected average power of the main signal to an average power of the main signal output by the radio frequency amplifying circuit, and adding a logarithm to the selected minimum power of the power adjuster to obtain a The first power adjustment factor is described.

 With reference to the second aspect and the foregoing possible implementation manner, in another possible implementation manner, the determining, by the power of the spurious signal, a second power adjustment coefficient, specifically:

 The ratio of the input signal power required to achieve the optimum signal to noise ratio of the selected ADC to the power of the spurious signal is logarithmically obtained to obtain the second power adjustment factor.

 With reference to the second aspect and the foregoing possible implementation manner, in another possible implementation manner, the power regulator includes: a low noise power amplifier or an adjustable attenuator.

An embodiment of the present invention provides a feedback link and an implementation method thereof, where a first power adjuster is added to a feedback link, and the first power adjuster calculates a first power adjustment coefficient according to an average power of the main signal, and according to the first The power adjustment coefficient adjusts the power of the second output signal, and the adjusted second output signal is input to the first ADC for sampling, and then the compensation signal is calculated by the DSP, so that the RF amplifying circuit performs power on the initial main signal according to the compensation signal. Compensation, in the prior art, directly inputting the second output signal to the first ADC for sampling, and calculating the compensation signal by the DSP, the partial main signal that cannot be collected due to the dynamic range limitation of the ADC device passes The adjustment of the first power regulator can also be obtained, so that the RF output signal can be accurately sampled without depending on the performance of the ADC device, and the accurate compensation signal is calculated by the DSP to calculate the initial main signal. The compensation is finally amplified by the RF amplifying circuit to obtain a linearly amplified initial main signal. 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 description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any inventive labor.

 1 is a schematic structural diagram of a feedback link according to Embodiment 1 of the present invention;

 1 is a schematic structural diagram of a feedback link according to Embodiment 1 of the present invention;

 FIG. 3 is a schematic diagram of a method for implementing a feedback link according to Embodiment 3 of the present invention; FIG. 4 is a schematic diagram of another method for implementing a feedback link according to Embodiment 3 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 only a part of the embodiments of the present invention, but not all of the 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 are within the scope of the present invention.

 Example 1

 The embodiment of the invention provides a feedback link, which is applied to a radio frequency amplifying circuit, and the radio frequency amplifying circuit receives an initial main signal, and outputs a first output including a main signal and a spurious signal after being amplified by the radio frequency amplifying circuit. The signal, as shown in FIG. 1, the feedback link may include: a coupler 11, a first power adjuster 12, a first ADC 13, and a digital signal processor (Digitai S gnal Processor, DSP) 14.

 An input end of the coupler 11 is connected to an output end of the radio frequency amplifying circuit, and configured to receive a first output signal of the radio frequency amplifying circuit, and obtain a second one from the first output signal according to a coupling ratio configured in advance The signal is output and output to the first power adjuster 12.

Wherein, since the radio frequency amplifying circuit generally operates in a non-linear region, the initial main signal is amplified by the radio frequency amplifying circuit, and the first output signal obtained is severely distorted, in order to reduce Distortion, the amplified first output signal can be sampled and corrected in real time using DPD technology. Therefore, the second output signal of the partial power can be obtained from the first output signal by the coupler 11 to calculate the compensation signal according to the second output signal, and compensate the initial main signal according to the compensation signal, thereby reducing Distortion of the first output signal. The coupling ratio of the coupler 11 is configured in advance in the coupler 11, and the specific calculation method of the coupling ratio is: w

= 101og(^) - A: ₂

w _x

Where ^ is the coupling ratio of the coupler 11, which is the minimum amplification factor of the first power amplifier, ^ is the expected average power of the main signal, and ₂ is the maximum power of the input signal required by the first ADC ₁₃ to achieve the optimum signal-to-noise ratio.

 An input end of the first power adjuster 12 is connected to an output end of the coupler 11 for receiving a second output signal output by the coupler 11 and calculating a first power adjustment according to an average power of the main signal And adjusting a power of the second output signal by using the first power adjustment coefficient, and outputting the adjusted second output signal to the first ADC 13.

 Wherein, in the prior art, the second output power obtained by the coupler 11 is directly input to the first ADC 13, but since the dynamic range of the first ADC 13 is limited, the input is first

In the embodiment of the present invention, the second output signal obtained by the coupler 11 is first input to the first power adjuster 12 for the purpose of solving the problem in the prior art. Adjusting, and outputting the adjusted second output signal to the first

ADC13, this can improve the accuracy of the digital signal obtained after sampling.

 The specific calculation method of the first power adjustment coefficient is:

 w

 L = 101og (―^ ) + ^

W _x

 Where ^ is the first power adjustment coefficient, ^ is the coupling ratio of the coupler 11, which is the average power of the main signal output by the RF amplification circuit, and the expected average power of the main signal.

An input end of the first ADC 13 is connected to an output end of the first power adjuster 12, and configured to receive the adjusted second output signal, and convert the adjusted second output signal into The digital signal is output to the DSP 14.

 In order to calculate the compensation signal better, the second output signal is processed by the digital signal, so the first ADC 13 performs analog-to-digital conversion on the second output signal by an analog-to-digital conversion technique to obtain a digitized second output signal.

 An input end of the DSP 14 is connected to an output end of the first ADC 13 for receiving a digital signal output by the first ADC 13, and calculating a compensation signal according to the digital signal, and transmitting the compensation signal to the And a radio frequency amplifying circuit, wherein the radio frequency amplifying circuit performs power compensation on the initial main signal according to the compensation signal.

In order to facilitate the understanding of those skilled in the art, the initial main signal of the input RF amplifying circuit is the first output signal is 7, due to the nonlinearity of the RF amplifying circuit, etc., λ γ = ΝΚΧ , where N is Magnification, which is a nonlinear coefficient. The purpose of the RF amplifying circuit design is to make the output signal linearly amplify the input signal, so it is necessary to transform the input signal, that is, to compensate the initial main signal, so that the compensated initial main signal is; ^ = -, then Γ = NKX ₁ -> Y = ΝΚ(Κ~ ^ι Χ) - > Υ = ΝΧ , so that the initial main signal of linear amplification can be obtained.

The DSP14 effect compensation signal is calculated, i.e., calculate - ^1, and the RF amplifier circuit according to - ^one pair of compensating the original master signal, the original main signal amplifying compensation, can be obtained initial linearly amplified main signal .

 The specific calculation process of the compensation signal is:

 The second output signal calculated by the DSP 14 based on the digital signal transmitted by the first ADC 13 is:

_ 2 ^Νί - 1

^I ADC\ - _{j kL k}

 10^ x lO^

为第一 ADC13的位宽， ^为耦合器 11的耦合比， ^为第一功率调整系数。 已知 γ = ΝΚΧ，且 L N均已知 ,可以得到 Κ~^λ = ΝΧΥ~^λ ,即 Κ-、 = NXY_ADCl~^l , 将计算所得的 ^_∞1代入式^：-ι = NXY_ADCl~^l即可算得补偿信号 f '。 Where _∞1 is the second output signal calculated by DSP14, JT ₂ is the signal of the first ADC13, and ^ is the maximum power of the input signal required by the first ADC13 to achieve the optimal signal-to-noise ratio,

Is the bit width of the first ADC 13, ^ is the coupling ratio of the coupler 11, and ^ is the first power adjustment coefficient. It is known that γ = ΝΚΧ, and LN is known, and Κ~ ^λ = ΝΧΥ~ ^λ can be obtained, that is, Κ-, = NXY _ADCl ~ ^l , and the calculated ^ _{∞1 is} substituted into ^:-ι = NXY _ADCl ~ ^l The compensation signal f ' can be calculated.

The DSP 14 inputs the calculated compensation signal ^-1 to the RF amplifying circuit, and the RF amplifying circuit can compensate the initial main signal, the compensated initial main signal is -, and then the RF main circuit is used to amplify the compensated initial main signal, thus A linearly amplified initial main signal can be obtained.

 An embodiment of the present invention provides a feedback link, where a first power adjuster is added to a feedback link, and the first power adjuster calculates a first power adjustment coefficient according to an average power of the main signal, and adjusts according to the first power adjustment coefficient. The power of the second output signal is input to the first ADC for sampling, and then the compensation signal is calculated by the DSP, so that the RF amplifying circuit performs power compensation on the initial main signal according to the compensation signal, and In the prior art, the second output signal is directly input to the first ADC for sampling, and the compensation signal is calculated by the DSP, and the part of the main signal that cannot be collected is subjected to the first power adjustment due to the limitation of the dynamic range of the ADC device. After the adjustment of the device, the set can also be obtained, so that the RF output signal can be accurately sampled without relying on the performance of the ADC device, and the accurate compensation signal is calculated by the DSP to compensate the initial main signal, and finally The amplified main frequency amplification circuit obtains a linearly amplified initial main signal.

 Example 2

 The embodiment of the invention provides a feedback link, which is applied to a radio frequency amplifying circuit, and the radio frequency amplifying circuit receives an initial main signal, and outputs a first output including a main signal and a spurious signal after being amplified by the radio frequency amplifying circuit. Signal, as shown in FIG. 2, the feedback link may include: a coupler 21, a first power regulator 22, a first ADC 23, and a DSP 24.

 An input end of the coupler 21 is connected to an output end of the radio frequency amplifying circuit, and configured to receive a first output signal of the radio frequency amplifying circuit, and obtain a second one from the first output signal according to a coupling ratio configured in advance The signal is output and output to the first power adjuster 22.

An input end of the first power adjuster 22 is connected to an output end of the coupler 21 for receiving a second output signal output by the coupler 21, according to an average power meter of the main signal Calculating a first power adjustment coefficient, adjusting a power of the second output signal by using the first power adjustment coefficient, and outputting the adjusted second output signal to the first ADC 23.

 An input end of the first ADC 23 is connected to an output end of the first power adjuster 22, configured to receive the adjusted second output signal, and convert the adjusted second output signal into a digital signal Output to the DSP 24.

 Further, since the resolution that the ADC can provide is limited, when the main signal energy occupies a large ratio, the low-energy spurious signal outside the main signal cannot be reliably sampled. Therefore, the embodiment of the present invention uses two paths. The ADC performs sampling, the first ADC 23 samples the main signal and the higher energy spurious signal, and the second ADC 27 only filters the amplified spurious signal after filtering the main signal through the band rejection filter 25, and the feedback link is also It may include: a band rejection filter 25, a second power adjuster 26, and a second ADC 27.

 An input end of the band rejection filter 25 is connected to an output end of the coupler 21 for acquiring a second output signal of the coupler 21, and filtering the main signal from the second output signal , get a spurious signal.

 The band rejection filter 25 filters out the main signal in the received second output signal to obtain a spurious signal, and outputs the spurious signal to the second power adjuster 26.

 The input end of the second power adjuster 26 is connected to the output end of the band rejection filter 25 for receiving the spurious signal, and calculating a second power adjustment coefficient according to the power of the spurious signal, The power of the spurious signal is adjusted by the second adjustment factor, and the adjusted spurious signal is output to the second ADC 27.

 The specific calculation method of the second power adjustment coefficient is: = 101 og ( )

Wherein, the second power adjustment coefficient, ₃ is the input signal power required for the second ADC 27 to reach the optimal signal to noise ratio, and ^ is the power of the spurious signal filtered by the band rejection filter 25.

The input end of the second ADC 27 is connected to the output of the second power adjuster 26, and is used for The adjusted spurious signal is received, and the adjusted spurious signal is converted into a digital spurious signal and output to the DSP 24.

 The input end of the DSP 24 is connected to the output ends of the first ADC 23 and the second ADC 27 for receiving the digital signal output by the first ADC 23 and the digital spurious signal output by the second ADC 27, and outputting the first ADC 23 Combining the digital signal and the digital spurious signal output by the second ADC 27 into a digital feedback signal, calculating a compensation signal according to the digital feedback signal, and transmitting the compensation signal to the radio frequency amplifying circuit, so that the radio frequency The amplifying circuit performs power compensation on the initial main signal according to the compensation signal.

 The specific calculation process of the compensation signal is:

Bian-like signal is provided a first ADC23 _Χ Ί, the second signal sample to preclude ADC27 JT _3, a first minimum resolution signal ADC23 preclude a sample value. The band rejection filter 25 has a passband gain of . It is assumed that the first ADC 23 and the second ADC 27 have the same bit widths as Λ^ and N ₂ , respectively.

The minimum resolution signal of the first ADC 23 mapped to the input of the second ADC 27 is:

Wherein, int represents rounding, ₂ is the maximum power of the input signal required by the first ADC 23 to achieve the best signal to noise ratio, ^ is the input signal power required by the second ADC 27 to achieve the best signal to noise ratio, for the first power adjustment The coefficient is the second power adjustment factor.

 Then, the effective signal of the second ADC 27 is (because the first ADC can sample the spurious energy of the higher energy, the first ADC 23 has to be removed from the second ADC 27):

X ₆ = X ₃ mod X ₅

 Among them, mod is the remainder operation.

 Then, the second output signal calculated by the DSP 24 according to the digital spur signal transmitted by the second ADC 27 is:

ΙΟ^ χΙΟ^ χ ΙΟ ^ The second output signal calculated by the DSP 24 based on the digital signal output by the first ADC 23 and the digital spur signal output by the second ADC 27 is:

7 ¹ = 7 ¹ ADC\ + τ Y ¹ ADC2

Therefore, DSP24 can substitute the calculated y into the formula -^ N F- ¹ , calculate the compensation signal and then compensate the initial input signal according to the compensation signal, so that the compensated initial main signal is linearly amplified by the RF amplification circuit. signal.

 It should be noted that the first power regulator and the second power regulator in the embodiment of the present invention may be a low noise power amplifier or an adjustable attenuator or the like.

 It should be noted that, in the embodiment of the present invention, the coupling ratio of the coupler 21 and the first power adjustment coefficient are the same as the specific calculation formulas in the first embodiment, and the embodiments of the present invention are not described in detail herein.

 An embodiment of the present invention provides a feedback link and an implementation method thereof, where a first power adjuster is added to a feedback link, and the first power adjuster calculates a first power adjustment coefficient according to an average power of the main signal, and according to the first The power adjustment coefficient adjusts the power of the second output signal, and the adjusted second output signal is input to the first ADC for sampling, and then the compensation signal is calculated by the DSP, so that the RF amplifying circuit performs power on the initial main signal according to the compensation signal. Compensation, in the prior art, directly inputting the second output signal to the first ADC for sampling, and calculating the compensation signal by the DSP, the partial main signal that cannot be collected due to the dynamic range limitation of the ADC device passes The adjustment of the first power regulator can also be obtained, so that the RF output signal can be accurately sampled without depending on the performance of the ADC device, and the accurate compensation signal is calculated by the DSP to calculate the initial main signal. The compensation is finally amplified by the RF amplifying circuit to obtain a linearly amplified initial main signal.

 Moreover, using two ADCs, the second channel filters the main signal through the bandpass filter, so that the resolution provided by the ADC is limited, and the main signal energy can not be reliably sampled when the main signal energy occupies a large ratio. The low-energy spurious signal can be sampled by the second ADC, further improving the accuracy of the sample.

Example 3 An embodiment of the present invention provides a method for implementing a feedback link. As shown in FIG. 3, the method includes:

301. Receive a first output signal of the radio frequency amplifying circuit, and obtain a second output signal from the first output signal according to a coupling ratio configured in advance.

 302. Calculate a first power adjustment coefficient according to an average power of the primary signal, and adjust a power of the second output signal by using the first power adjustment coefficient.

 The calculating the first power adjustment coefficient according to the average power of the main signal, specifically: taking a logarithm of a ratio of an expected average power of the main signal and an average power of the main signal output by the radio frequency amplifying circuit, The result obtained after the logarithm is added to the minimum magnification of the selected power regulator to obtain the first power adjustment coefficient.

 303. Convert the adjusted second output signal into a digital signal.

 304. Calculate a compensation signal according to the digital signal, and send the compensation signal to the radio frequency amplifying circuit, so that the radio frequency amplifying circuit performs power compensation on the initial main signal according to the compensation signal.

 Further, as shown in FIG. 4, the method may further include:

 305. Filter the main signal from the second output signal to obtain a spurious signal.

 306. Calculate a second power adjustment coefficient according to a power of the spurious signal, and adjust a power of the spurious signal by using the second adjustment coefficient.

 Calculating a second power adjustment coefficient according to the power of the spurious signal, specifically: taking a logarithm of a ratio of an input signal power required for the selected ADC to an optimal signal to noise ratio and a power of the spurious signal , obtaining the second power adjustment coefficient.

 307. Convert the adjusted spurious signal into a digital spurious signal.

 Step 304 can be replaced with the following step 308:

308. Combine the digital signal and the digital spur signal into a digital feedback signal, calculate a compensation signal according to the digital feedback signal, and send the compensation signal to the radio frequency amplifying circuit, so that the radio frequency amplifying circuit is configured according to The compensation signal performs power compensation on the initial main signal. It should be noted that, in the specific calculation method of the parameters in the embodiment of the present invention, reference may be made to the specific calculation method of the corresponding parameters in the embodiment 1 and the embodiment 2. The embodiment of the present invention will not be described in detail herein.

 An embodiment of the present invention provides a feedback link implementation method, which calculates a first power adjustment coefficient according to an average power of a primary signal, and uses the first power adjustment coefficient to adjust a power of the second output signal, and adjusts the The second output signal is converted into a digital signal, and then the compensation signal is calculated according to the digital signal, and the compensation signal is sent to the radio frequency amplifying circuit, so that the radio frequency amplifying circuit performs power compensation on the initial main signal according to the compensation signal, and the existing In the technology, the second output signal is directly sampled, and the compensation signal is compared, and the dynamic range of the ADC device is limited, and part of the main signal that cannot be collected is adjusted by the first power regulator. The set makes the output of the RF output signal independent of the performance of the ADC device, and can accurately calculate the compensation signal to compensate the initial main signal, and finally obtain the initial amplification of the linear amplification after amplification by the RF amplification circuit. signal.

 Moreover, using two ADCs, the second channel filters the main signal through the bandpass filter, so that the resolution provided by the ADC is limited, and the main signal energy can not be reliably sampled when the main signal energy occupies a large ratio. The low-energy spurious signal can be sampled by the second ADC, further improving the accuracy of the sample.

 Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus necessary general hardware, and of course, by hardware, but in many cases, the former is a better implementation. . Based on such understanding, the technical solution of the present invention, which is essential or contributes to the prior art, may be embodied in the form of a software product stored in a readable storage medium, such as a floppy disk of a computer. A hard disk or optical disk or the like includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform the methods described in various embodiments of the present invention.

The above is only the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any change or replacement that can be easily conceived by those skilled in the art within the technical scope of the present invention is All should be covered by the scope of the present invention. Therefore, this issue The scope of protection shall be subject to the scope of protection of the claims.

Claims

Rights request 1. A feedback link applied to a radio frequency amplification circuit. The radio frequency amplification circuit receives an initial main signal, and after amplification processing by the radio frequency amplification circuit, outputs a first output signal including the main signal and spurious signals, so The feedback link includes: a coupler, a first analog-to-digital converter ADC and a digital signal processor DSP; the feedback link also includes: a first power regulator; The input end of the first power regulator is connected to the output end of the coupler, the input end of the coupler is connected to the output end of the radio frequency amplifier circuit, and the input end of the first ADC is connected to the third The output end of a power regulator is connected, the output end of the first ADC is connected to the input end of the DSP, the output end of the DSP is connected to the input end of the radio frequency amplifier circuit; the coupler is used for Receive the first output signal of the radio frequency amplifier circuit, obtain the second output signal from the first output signal according to the coupling ratio configured in advance, and output it to the first power regulator; The first power adjuster is configured to receive the second output signal output by the coupler, calculate a first power adjustment coefficient according to the average power of the main signal, and adjust the first power adjustment coefficient using the first power adjustment coefficient. the power of the second output signal, and output the adjusted second output signal to the first ADC; The first ADC is used to receive the adjusted second output signal, convert the adjusted second output signal into a digital signal and output it to the DSP; The DSP is configured to receive the digital signal output by the first ADC, calculate a compensation signal based on the digital signal, and send the compensation signal to the radio frequency amplifier circuit, so that the radio frequency amplifier circuit can The compensation signal performs power compensation on the initial main signal. 2. The feedback link according to claim 1, the feedback link further comprising: a second power regulator, a second ADC and a band-stop filter; The input end of the band stop filter is connected to the output end of the coupler, the input end of the second power regulator is connected to the output end of the band stop filter, and the output of the second power regulator terminal is connected to the input terminal of the second ADC, and the output terminal of the second ADC is connected to the DSP The input terminal is connected; The band stop filter is used to obtain the second output signal of the coupler, and filter out the main signal from the second output signal to obtain spurious signals; The second power adjuster is used to receive the spurious signal, calculate a second power adjustment coefficient according to the power of the spurious signal, and use the second adjustment coefficient to adjust the power of the spurious signal, and output the adjusted spurious signal to the second ADC; The second ADC is used to receive the adjusted spurious signal, and convert the adjusted spurious signal into a digital spurious signal and output it to the DSP; The DSP is also used to receive the digital spurious signal output by the second ADC, and combine the digital signal output by the first ADC and the digital spurious signal output by the second ADC into a digital feedback signal, according to the The digital feedback signal is calculated to obtain a compensation signal, and the compensation signal is sent to the radio frequency amplifier circuit, so that the radio frequency amplifier circuit performs power compensation on the initial main signal according to the compensation signal. 3. The feedback link according to claim 1, the first power regulator is specifically configured to: take the logarithm of the ratio of the expected average power of the main signal and the average power of the main signal output by the radio frequency amplifier circuit, Add the result obtained after taking the logarithm to the minimum amplification factor of the first power regulator to obtain the first power adjustment coefficient of the first power regulator, and use the first power adjustment coefficient to adjust the the power of the second output signal, and output the adjusted second output signal to the first ADC. 4. The feedback link according to claim 2, the second power regulator is specifically used to: adjust the input signal power required by the second ADC to achieve the optimal signal-to-noise ratio and the noise output by the band stop filter. Take the logarithm of the ratio of the power of the spurious signal to obtain the second power adjustment coefficient of the second power regulator, use the second adjustment coefficient to adjust the power of the spurious signal, and use the adjusted spurious signal output to the second ADC. 5. The feedback link according to any one of claims 1-4, the first power regulator and the second power regulator include: a low-noise power amplifier or an adjustable attenuator. 6. A feedback link implementation method, applied to a radio frequency amplification circuit, the radio frequency amplification circuit The channel receives the initial main signal, and after amplification processing by the radio frequency amplification circuit, outputs a first output signal including the main signal and spurious signals, including: Receive the first output signal of the radio frequency amplifier circuit, and obtain the second output signal from the first output signal according to the coupling ratio configured in advance; Calculate a first power adjustment coefficient according to the average power of the main signal, and use the first power adjustment coefficient to adjust the power of the second output signal; Convert the adjusted second output signal into a digital signal; A compensation signal is calculated according to the digital signal, and the compensation signal is sent to the radio frequency amplification circuit, so that the radio frequency amplification circuit performs power compensation on the initial main signal according to the compensation signal. 7. The feedback link implementation method according to claim 6, the method further comprising: filtering out the main signal from the second output signal to obtain spurious signals; Calculate a second power adjustment coefficient according to the power of the spurious signal, and use the second adjustment coefficient to adjust the power of the spurious signal; Convert the adjusted spurious signal into a digital spurious signal; The digital signal and the digital spurious signal are combined into a digital feedback signal, a compensation signal is calculated according to the digital feedback signal, and the compensation signal is sent to the radio frequency amplification circuit, so that the radio frequency amplification circuit is based on the The compensation signal performs power compensation on the initial main signal. 8. The feedback link implementation method according to claim 6, wherein the first power adjustment coefficient is calculated according to the average power of the main signal, specifically: Take the logarithm of the ratio of the expected average power of the main signal and the average power of the main signal output by the radio frequency amplifier circuit, and add the logarithm of the result to the minimum amplification factor of the selected power regulator to obtain The first power adjustment coefficient. 9. The feedback link implementation method according to claim 6, wherein the second power adjustment coefficient is calculated according to the power of the spurious signal, specifically: The input signal power required to achieve the best signal-to-noise ratio of the selected ADC and the spurious signal The ratio of the powers is logarithmically obtained to obtain the second power adjustment coefficient. 10. The feedback link implementation method according to claim 8, the power regulator includes: a low-noise power amplifier or an adjustable attenuator.