DPD feedback signal gain compensation method and device, medium and product

Abstract

The invention discloses a DPD feedback signal gain compensation method and device, a medium and a product, and relates to the technical field of communication. The method comprises the following steps: after an original signal is amplified to form an amplified signal, carrying out sampling and analog-to-digital conversion processing on the amplified signal to obtain IQ sampling signals; carrying out normalization processing on the IQ two-path sampling signals to obtain a feedback signal in a complex signal form; under the condition that first power is determined according to the root-mean-square of the original signal, second power is determined according to the root-mean-square of the feedback signal; determining an amplitude difference between the feedback signal and the original signal based on the first power and the second power; performing amplitude alignment adjustment on the feedback signal according to the amplitude difference and the amplitude of the original signal; and based on the time delay of the original signal, carrying out time delay alignment adjustment on the amplitude alignment signal. According to the invention, the nonlinear effect of the power amplifier is effectively controlled and compensated, the signal-to-noise ratio of signals is improved, the bit error rate is reduced, and the condition of signal distortion is reduced.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a DPD feedback signal gain compensation method, device, medium and product. Background Art

[0002] Wireless transmitters are widely used in many fields such as radio and television, mobile communication base stations, target radar detection, data links, electronic countermeasure equipment, etc. High-power shortwave AM (amplitude modulation) transmitters are used to transmit AM modulated signals. They are an important part of wireless communication systems and have a wide range of applications, such as broadcasting, power suppression, and anti-interference.

[0003] In related technologies, in order to ensure that the signal can propagate to a longer distance and cover a wider area, a power amplifier is usually used to increase the power of the transmitted signal. However, the power amplifier will have nonlinear effects when amplifying the signal, especially when the signal strength reaches the compression point of the power amplifier, this nonlinearity will increase significantly, resulting in signal distortion, such as amplitude compression, spectrum expansion, etc., which will seriously reduce the quality of the signal and affect the reliability and efficiency of communication.

[0004] Therefore, how to effectively control and compensate for the nonlinear effects of power amplifiers is an important technical challenge in the current communications field. Summary of the invention

[0005] In view of the above-mentioned technical problems and defects, the purpose of the present invention is to provide a DPD feedback signal gain compensation method, device, medium and product, which can effectively control and compensate for the nonlinear effects of the power amplifier, improve the signal-to-noise ratio of the signal, reduce the bit error rate, and reduce signal distortion such as amplitude compression and spectrum expansion.

[0006] To achieve the above-mentioned purpose, in a first aspect, the present invention provides a DPD feedback signal gain compensation method, comprising: after the original signal is amplified to form an amplified signal, sampling and analog-to-digital conversion processing are performed on the amplified signal to obtain an IQ two-way sampling signal; the IQ two-way sampling signal is normalized to obtain a feedback signal in the form of a complex signal; when a first power is determined according to the root mean square of the original signal, a second power is determined according to the root mean square of the feedback signal; based on the first power and the second power, an amplitude difference between the feedback signal and the original signal is determined; according to the amplitude difference and the amplitude of the original signal, an amplitude alignment adjustment is performed on the feedback signal to obtain an amplitude alignment signal; based on the delay of the original signal, a delay alignment adjustment is performed on the amplitude alignment signal to obtain an amplitude delay alignment signal.

[0007] The present invention realizes digital pre-distortion (DPD) compensation of the amplified signal through the above method, improves the signal quality, and improves the communication reliability and efficiency. First, the IQ two-way sampling signal obtained by sampling and analog-to-digital conversion provides an accurate data basis for the digital processing of the signal. Secondly, the normalization process ensures the consistency of the signal within the numerical range, which is convenient for subsequent processing. By calculating the root mean square of the original signal and the feedback signal, the method accurately determines the power difference between the two and provides key parameters for amplitude alignment. The amplitude alignment adjustment compensates for the nonlinear distortion generated by the power amplifier, and the delay alignment adjustment further ensures the synchronization of the signal in time. Therefore, the present invention effectively controls and compensates for the nonlinear effect of the power amplifier, not only improves the signal-to-noise ratio of the signal, reduces the bit error rate, reduces the signal distortion such as amplitude compression and spectrum expansion, but also enhances the coverage and transmission distance of the signal, thereby providing users with a more stable and efficient communication experience in a complex and changeable communication environment.

[0008] In combination with some embodiments of the first aspect, in some embodiments, after the step of performing amplitude alignment adjustment on the feedback signal according to the amplitude difference and the amplitude of the original signal to obtain an amplitude aligned signal, it also includes: determining the normalized mean square error between the feedback signal and the original signal; if the normalized mean square error is greater than a set threshold, re-sampling the amplified signal.

[0009] By adopting the technical solution of the above embodiment, the adaptability and accuracy of the DPD compensation method are enhanced by introducing the evaluation of the normalized mean square error (NMSE) and comparing it with the preset threshold. When the NMSE exceeds the threshold, the resampling and processing process is triggered to ensure that the signal compensation is always kept in the best state, thereby significantly improving the reliability of signal processing and the overall performance of the system.

[0010] In combination with some embodiments of the first aspect, in some embodiments, before the step of sampling and analog-to-digital conversion of the amplified signal to obtain IQ two-way sampling signals, the method includes: converting the original signal into an AM signal according to an AM modulation signal formula, wherein the AM modulation signal formula includes: Among them, x(n) represents the AM signal corresponding to the original signal, α is the modulation coefficient, f is the frequency, n is the signal sample point number, t is the time variable, and j is the imaginary unit.

[0011] By adopting the technical solution of the above embodiment, a standardized signal processing starting point is provided for DPD compensation by converting the original signal into an AM signal before sampling. This method ensures that the signal has a consistent format and characteristics before analog-to-digital conversion, simplifies the subsequent processing flow, and improves the consistency and accuracy of signal processing.

[0012] In combination with some embodiments of the first aspect, in some embodiments, determining the first power according to the root mean square of the original signal includes: determining the first power of the original signal according to a signal power formula, and the signal power formula includes: x power =20log 10 (rms(x(n))); Among them, x power represents the first power of the original signal, and rms(x(n)) represents the root mean square of the original signal.

[0013] By adopting the technical solution of the above embodiment, a standardized metric is provided for determining the first power of the original signal by clarifying the calculation method of the signal power. This clear power evaluation provides an accurate benchmark for the amplitude alignment and delay alignment of the signal, ensuring the accuracy of the compensation process and the optimization of the communication system performance.

[0014] In combination with some embodiments of the first aspect, in some embodiments, before determining the first power according to the root mean square of the original signal, the method includes: determining the root mean square of the original signal according to a signal root mean square formula, where the signal root mean square formula includes: Among them, rms(x(n)) represents the root mean square of the original signal, x n is the value of the nth original signal sample point, and N is the total number of signal samples.

[0015] By adopting the technical solution of the above embodiment, an accurate and repeatable method is provided for signal power evaluation by specifying the calculation formula of the original signal RMS. This step ensures the accurate calculation of signal power and provides key data support for amplitude alignment adjustment in DPD compensation.

[0016] In combination with some embodiments of the first aspect, in some embodiments, the step of performing amplitude alignment adjustment on the feedback signal according to the amplitude difference and the amplitude of the original signal to obtain the amplitude aligned signal includes: determining the amplitude aligned signal according to a signal difference formula, the signal difference formula is used to represent the amplitude difference between the feedback signal and the original signal, the signal difference formula includes, ; Among them, x(n) represents the AM signal corresponding to the original signal, y(n-τ) represents the value of the feedback signal before the time delay τ, G represents the amplitude difference, θ is the phase difference, and w is the frequency deviation.

[0017] By adopting the technical solution of the above embodiment, a quantitative method is provided for amplitude alignment adjustment by defining a signal difference formula. This formula not only reveals the amplitude difference between the feedback signal and the original signal, but also provides a necessary mathematical model for achieving accurate amplitude compensation, thereby improving the accuracy of signal compensation.

[0018] In combination with some embodiments of the first aspect, in some embodiments, the step of determining the amplitude difference between the feedback signal and the original signal based on the first power and the second power includes: calculating the amplitude difference between the feedback signal and the original signal according to an amplitude difference formula, and the amplitude difference formula includes: G=x power / y power ; Among them, x power represents the first power, y power represents the second power.

[0019] By adopting the technical solution of the above embodiment and applying the amplitude difference formula, the amplitude difference calculation between the feedback signal and the original signal is made more direct and accurate. This step provides clear guidance for the amplitude alignment of the signal, helps to reduce nonlinear distortion, and improves the quality of signal transmission and the overall performance of the communication system.

[0020] In a second aspect, an embodiment of the present invention provides an electronic device, comprising: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the electronic device to execute the method described in the first aspect and any possible implementation method of the first aspect.

[0021] In a third aspect, the present invention provides a computer-readable storage medium comprising instructions, which, when executed on an electronic device, enables the electronic device to execute the method described in the first aspect and any possible implementation of the first aspect.

[0022] In a fourth aspect, the present invention provides a computer program product comprising instructions, which, when executed on an electronic device, enables the electronic device to execute the method described in the first aspect and any possible implementation of the first aspect.

[0023] It is understandable that the electronic device provided in the second aspect, the storage medium provided in the third aspect, and the computer program product provided in the fourth aspect are all used to execute the method provided in the present invention. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method, which will not be repeated here.

[0024] One or more technical solutions provided by the present invention have at least the following technical effects or advantages: 1. The present invention realizes accurate compensation for the nonlinear characteristics of the power amplifier through the digital pre-distortion (DPD) feedback signal gain compensation method, significantly improving the transmission quality during the signal amplification process. By predicting and applying compensation before signal amplification, the amplitude compression and spectrum expansion caused by amplifier nonlinearity are effectively reduced, ensuring the integrity and accuracy of the signal, thereby enhancing the performance and reliability of the communication system.

[0025] 2. The present invention provides a means of adaptive adjustment and optimization for DPD compensation by introducing a normalized mean square error (NMSE) evaluation mechanism. When the NMSE exceeds a preset threshold, the system automatically resamples and processes the signal until the accuracy requirement is met. This intelligent feedback loop not only improves the accuracy of signal processing, but also enhances the system's adaptability to different communication environments and changes in conditions.

[0026] 3. The present invention makes careful adjustments to the amplitude alignment and delay alignment of the original signal and the feedback signal. The technical solution ensures that the signal can maintain a high degree of consistency with the original signal after passing through the power amplifier and the transmission path. This precise signal alignment compensates for time delay and phase deviation, improves signal synchronization, and reduces bit error rate, thereby improving communication efficiency and user communication experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings herein are incorporated into and constitute a part of the specification, showing embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings: Figure 1 is a flow chart of a DPD feedback signal gain compensation method according to an embodiment of the present invention; Figure 2 is a flow chart of another DPD feedback signal gain compensation method according to an embodiment of the present invention; Figure 3 is a schematic diagram of comparison between a feedback signal and an original signal in an embodiment of the present invention; Figure 4 It is a schematic diagram of the architecture of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The terms used in the following embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to be limiting of the present invention. As used in the specification of the present invention, the singular expressions "a", "a", "above", "the" and "this" are intended to also include plural expressions, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in the present invention refers to any or all possible combinations comprising one or more of the listed items.

[0029] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood as implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0030] It should also be noted that, unless otherwise clearly specified and limited, in the embodiments of the present invention, the terms such as "setting" and "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two components; it can be a wired communication connection or a wireless communication connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The embodiments of the present invention are described in detail below.

[0031] Suppose a mobile communication base station in a crowded urban environment needs to transmit wireless signals to the surrounding area. In order to ensure that the signal can cover a wide area including tall buildings, subway stations and busy streets, the base station uses a power amplifier to increase the transmission power of the signal.

[0032] However, the power amplifier has a compression point. When the input power gradually increases, the output power does not increase linearly, but reaches an inflection point, namely the compression point. After this inflection point, the growth rate of the output power will gradually decrease until the output power reaches saturation and no longer increases with the increase of input power.

[0033] Therefore, when the signal strength approaches the compression point of the power amplifier (such as the 1dB compression point), the nonlinear characteristics of the amplifier begin to appear, causing some parts of the signal to be over-amplified while other parts are under-amplified. This nonlinear effect causes the signal amplitude compression and spectrum expansion.

[0034] As a result, mobile devices on the receiving end may experience dropped calls, reduced data rates, or even complete signal loss, severely impacting the user’s communication experience and the overall performance of the network.

[0035] Therefore, an embodiment of the present invention provides a DPD feedback signal gain compensation method, which can improve the quality and reliability of signal transmission by compensating for the digital pre-distortion (DPD) of the signal. First, the analog signal is converted into a digital signal by sampling and analog-to-digital conversion of the amplified signal, which provides a basis for subsequent processing. Subsequently, the normalization process ensures the consistency of the signal within the numerical range, and the power calculation based on RMS (Root Mean Square) provides a basis for the accurate determination of the amplitude difference. In addition, through the amplitude alignment adjustment, the distortion caused by the nonlinear effect of the power amplifier is effectively compensated, ensuring the accuracy of the signal amplitude. The subsequent delay alignment adjustment ensures the synchronization of the signal in time and avoids signal misalignment or overlap caused by delay differences.

[0036] The embodiment of the present invention effectively controls and compensates for the nonlinear effect of the power amplifier through such DPD compensation measures, which not only improves the signal-to-noise ratio of the signal, reduces the bit error rate, reduces signal distortion such as amplitude compression and spectrum expansion, but also enhances the signal coverage and communication distance, thereby providing users with a more stable and efficient communication experience in a complex and changeable communication environment.

[0037] In addition, the application of this method also helps to reduce energy consumption and extend the life of equipment, and has important practical significance and broad application prospects for promoting the development of wireless communication technology.

[0038] Combine the following Figure 1 , specifically describes a DPD feedback signal gain compensation method according to an embodiment of the present invention. The method may include the following steps: Step 101: After the original signal is amplified to form an amplified signal, the amplified signal is sampled and analog-to-digital converted to obtain two-channel IQ sampling signals.

[0039] Specifically, the original signal is first sent to a power amplifier (PA), which is responsible for providing sufficient current or voltage gain to ensure that the signal can be transmitted into the air or over a long distance. In this process, the original signal is first modulated to adapt to the set communication standard and frequency band, and then amplified by the power amplifier. The design of the amplifier must take into account parameters such as efficiency, linearity, and bandwidth to ensure that the signal maintains its integrity and quality during the amplification process.

[0040] The amplified signal, also known as the amplified signal, has a higher power level, enabling it to cover a wider geographical area or overcome attenuation in the transmission medium. However, the nonlinear characteristics of the power amplifier may cause signal distortions such as amplitude compression or spectrum expansion, so digital pre-distortion (DPD) compensation is required after amplification to correct these distortions. The next step is to accurately sample the amplified signal.

[0041] The sampling process involves measuring the instantaneous amplitude of the amplified signal at specific time intervals, which are usually selected according to the Nyquist criterion to ensure that the signal can be accurately reconstructed. The analog-to-digital converter (ADC) then converts these instantaneous amplitude values ​​from the analog domain to the digital domain, generating a series of digital samples.

[0042] In the IQ sampling process, two parallel ADCs are usually involved to sample the in-phase (I) and quadrature (Q) components respectively. The I component is synchronized with the carrier signal, while the Q component is 90 degrees out of phase with the carrier signal.

[0043] In this way, the original analog signal is converted into two digital signals, namely, I-channel and Q-channel signals, which constitute IQ two-channel sampling signals and contain the amplitude and phase information of the signal.

[0044] Step 102: normalize the IQ sampling signals to obtain a feedback signal in the form of a complex signal.

[0045] Among them, normalization is a mathematical operation that scales the amplitude of the signal to a uniform range of values, usually [-1, 1] or [0, 1]. This ensures that the value of the signal does not exceed the processing capacity of the digital processing system during subsequent processing, while maintaining the proportional relationship between the signals.

[0046] First, the IQ signals represent the real and imaginary parts of the modulated signal, respectively. After they are converted into digital form by an analog-to-digital converter (ADC), they usually need to be scaled to fit the numerical range of the digital signal processing system. Normalization processing includes dividing each sample value by its maximum possible value, for example, dividing each sample point in the IQ signals by 32768. In this way, the original sample value is converted to the range of [-1,1], ensuring the numerical stability of the signal and the consistency of processing.

[0047] Next, the normalized I and Q signals are combined to form a complex signal. Specifically, if I norm and Q norm represent the normalized I and Q signals respectively, then the complex signal s can be expressed as s = I norm +jQ norms, where j is the imaginary unit. This complex signal not only contains the amplitude information of the original signal, but also retains the phase information, providing a complete and convenient mathematical model for subsequent signal processing and analysis. Complex signals are more convenient for mathematical operations and analysis, especially in the frequency domain analysis and transformation of signals. The complex signal form can express the amplitude and phase information of the signal at the same time, which is crucial for understanding and correcting signal characteristics.

[0048] The normalization process not only improves the flexibility and accuracy of signal processing, but also provides standardized input for further analysis and pre-distortion compensation of the signal. This step is the basis for efficient and accurate digital signal processing, which enables the amplitude and phase information of the signal to be accurately represented and processed in the digital domain, laying the foundation for the ultimate realization of accurate compensation and optimization of the signal.

[0049] Step 103: When the first power is determined according to the root mean square of the original signal, the second power is determined according to the root mean square of the feedback signal.

[0050] In the DPD technology, it is crucial to accurately measure and compare the energy levels of the original signal and the feedback signal. In this embodiment, the first power and the second power of the two signals are determined by calculating the root mean square (RMS) of the original signal and the feedback signal.

[0051] RMS is a measure of signal energy, which provides an average value of signal strength, thereby allowing for quantitative analysis of the power of the signal. In this embodiment, the RMS value of the original signal is first calculated, which reflects the energy state of the signal before being processed by the power amplifier. Then, the same RMS calculation is performed on the feedback signal obtained after ADC conversion to obtain its second power. These two power values ​​provide a benchmark for evaluating the nonlinear distortion that may occur in the signal during the amplification process.

[0052] Through this precise power assessment, it can be ensured that the energy characteristics of the signal are accurately reflected, laying a solid foundation for subsequent signal correction and optimization.

[0053] Step 104: Determine an amplitude difference between the feedback signal and the original signal based on the first power and the second power.

[0054] This step can analyze and quantify the amplitude difference between the feedback signal and the original signal. After determining the first power of the original signal and the second power of the feedback signal, the amplitude change of the signal after passing through the power amplifier is evaluated by comparing the two power values.

[0055] If the second power is significantly different from the first power, this may indicate that the signal has suffered nonlinear distortion or other effects during the amplification process. By calculating the ratio or difference of these two power values, a specific measure of the change in signal amplitude can be obtained.

[0056] This amplitude difference is key information for adjusting the feedback signal to match the original signal. It not only reveals the behavior of the signal in the power amplifier, but also provides the necessary data support for subsequent amplitude alignment adjustments. By accurately determining the amplitude difference, it can be ensured that the signal can be restored to a close to original state after compensation processing, thereby improving the overall performance of the communication system.

[0057] Step 105: perform amplitude alignment adjustment on the feedback signal according to the amplitude difference and the amplitude of the original signal to obtain an amplitude aligned signal.

[0058] This step can correct the amplitude of the feedback signal to match the amplitude of the original signal, thereby compensating for the nonlinear distortion introduced by the power amplifier.

[0059] By accurately calculating the amplitude difference, each sample of the feedback signal can be adjusted. This adjustment ensures that the amplitude information of the signal is restored, making the peak value, average value and overall energy distribution of the signal closer to the original signal.

[0060] Amplitude alignment not only improves the quality of the signal, but also provides a basis for further signal processing, such as delay alignment and phase correction. Through amplitude alignment, the characteristics of the signal can be finely controlled in the digital domain to ensure that the signal can maintain its integrity and accuracy after passing through the communication system.

[0061] Step 106: Based on the delay of the original signal, perform delay alignment adjustment on the amplitude aligned signal to obtain an amplitude delay aligned signal.

[0062] After the amplitude of the signal is properly aligned, the problem of signal alignment in time is solved. This step is based on the delay characteristics of the original signal and performs delay alignment adjustment on the amplitude-aligned signal.

[0063] Delay alignment is a critical step in ensuring that the signal can be accurately reconstructed at the receiving end. It involves evaluating the delays that the signal may encounter during transmission and adjusting the position of the signal samples accordingly. By time-shifting the signal samples or introducing additional delays, it is possible to ensure that the various parts of the signal are synchronized in time, thereby avoiding signal overlap or misalignment caused by delay differences.

[0064] Specifically, first, by analyzing the waveform of the original signal and the waveform of the feedback signal, the relative position difference between the two on the time axis, that is, the time delay τ, is determined. Then, according to this time delay value, the amplitude-aligned signal is time-shifted to ensure that it is synchronized with the original signal in time. This shift may involve delaying or advancing the signal samples to compensate for any time offset caused by signal propagation or processing.

[0065] In this way, not only the amplitude of the signal is corrected, but the time structure of the signal is also precisely aligned, thus ensuring the integrity and accuracy of the signal, which is crucial for high-quality transmission and reception of the signal.

[0066] Finally, an amplitude-delay aligned signal is obtained, which is consistent with the original signal in both amplitude and time, thus providing a solid foundation for accurate signal demodulation.

[0067] The method of this embodiment significantly improves the efficiency and reliability of signal amplification and transmission in wireless communication systems through an innovative digital pre-distortion compensation strategy. Specifically, the method captures the details of the amplified signal through precise sampling and analog-to-digital conversion technology, and uses normalization processing to ensure the consistency of signal values ​​and the flexibility of processing. Furthermore, by comparing and analyzing the root mean square of the original signal and the feedback signal, the power change during the signal amplification process is accurately quantified, providing a scientific basis for amplitude alignment. The amplitude alignment adjustment of this method effectively compensates for the nonlinear distortion of the power amplifier, while the delay alignment adjustment ensures the precise synchronization of the signal in time.

[0068] Therefore, through this embodiment, the nonlinear characteristics of the power amplifier can be accurately grasped, and before the signal is amplified, the DPD feedback signal gain compensation method of this embodiment is applied in the digital domain to compensate the signal to be output to offset the expected distortion, ensuring that even after the signal passes through the amplifier, its amplitude and phase can still maintain the integrity close to the original signal. This preprocessing method effectively reduces the distortion caused by nonlinearity, such as amplitude compression and spectrum expansion, thereby improving the transmission quality of the signal, enhancing the signal-to-noise ratio and spectrum efficiency of the communication system, reducing the bit error rate, and ultimately achieving more reliable and efficient wireless communication.

[0069] The combination of these technologies not only optimizes signal quality and reduces communication errors, but also enhances the signal transmission distance and network coverage, so that the communication system can still maintain efficient and stable operation when facing complex environments and dynamic conditions. In addition, the implementation of this method also helps to reduce system energy consumption and extend the service life of equipment, which has far-reaching significance for promoting the continuous advancement of wireless communication technology and meeting the growing communication needs.

[0070] Combine the following Figure 2To further illustrate the DPD feedback signal gain compensation method of this embodiment, the method specifically includes the following steps: Step 201: convert the original signal into an AM signal according to an AM modulation signal formula.

[0071] Among them, the AM modulation signal formula includes, Among them, x(n) represents the AM signal corresponding to the original signal, which is the value of the original signal at the nth sample point after sampling; α is the modulation coefficient, which determines the modulation depth of the original signal on the carrier amplitude, and the value range can be 0 to 1. In this embodiment, the specific value can be 1, indicating 100% modulation.

[0072] f is the frequency of the modulation signal, which determines the oscillation speed of the AM signal and can be in the range of 60 Hz to 5 kHz. In this embodiment, the specific value can be 1 Hz; n is the signal sample point number, representing the discrete expression of the signal in time; in this embodiment, the sampling rate fs can be specifically 96ksps, so the number of samples in one cycle is fs / f=96. In order to characterize the statistical characteristics of the signal, 10 cycles are specially used for calculation, that is, the total number of samples is 96*10=960.

[0073] t is the time variable, indicating the change of the signal over time; j is an imaginary unit used to represent the phase information of the signal.

[0074] Through this AM modulation signal formula, the amplitude of the original signal is used to modulate a carrier signal with a frequency of f, thereby generating the final AM modulated signal, which can be used as a standard way to transmit information in broadcasting, wireless communications and other fields.

[0075] Through the AM modulation signal formula of this embodiment, it is explained in detail how to convert the original signal into the form of an AM signal, including the mathematical expression of the modulation signal and the definition of related parameters. This conversion not only retains the spectrum characteristics of the original signal, but also provides a standardized format for subsequent signal processing and analysis. By clarifying the parameters such as the modulation coefficient, frequency, time variable and imaginary unit in the modulation signal formula, the accurate representation of the signal in the digital domain is ensured, laying the foundation for accurate signal processing and compensation.

[0076] Step 202: determine the root mean square of the original signal according to a signal root mean square formula.

[0077] Among them, the signal root mean square formula includes, Among them, rms(x(n)) represents the root mean square of the original signal, xn is the value of the nth signal sample point, and N is the total number of signal samples.

[0078] The RMS reflects the average energy level of the signal over time and is often used to analyze the power characteristics of the signal or to evaluate the amplitude characteristics of the signal when performing digital pre-distortion compensation.

[0079] This embodiment further refines the calculation process of the original signal RMS by introducing the signal RMS formula. The formula details how to calculate the RMS through the value of the signal sample point, including the steps of squaring, summing, dividing by the total number of sample points, and finally taking the square root of all signal sample point values. This calculation method not only provides an accurate RMS evaluation method, but also ensures the accuracy and repeatability of the RMS calculation by clarifying the relationship between the sample point value and the total number. This is crucial for subsequent power determination and signal compensation because it directly affects the quality of signal processing and system performance.

[0080] Step 203: determine a first power according to the root mean square of the original signal.

[0081] This step specifically includes: determining the first power of the original signal according to a signal power formula, the signal power formula including: x power =20log 10 (rms(x(n))); Among them, x power represents the first power of the original signal, and rms(x(n)) represents the root mean square of the original signal.

[0082] In this embodiment, the first power is obtained by calculating the root mean square value of all sample points of the signal, which usually involves summing the squares of the signal sample point values, dividing by the total number of sample points, and finally taking the square root of the result.

[0083] By introducing this signal power formula, a standardized calculation method is provided for determining the first power of the original signal. This formula explains how to determine the power of a signal based on its root mean square (RMS), where RMS is a measure of signal energy stability and reflects the average energy level of the signal over time. Through this calculation, the power of the original signal can be accurately evaluated, providing the necessary data for subsequent power comparison and compensation. This method not only improves the accuracy of power evaluation, but also provides a benchmark for signal amplitude alignment and delay alignment adjustments, thereby ensuring the accuracy and effectiveness of the entire DPD compensation process.

[0084] Step 204: amplify the original signal to form an amplified signal.

[0085] Step 205: Sampling and analog-to-digital conversion are performed on the amplified signal to obtain IQ two-channel sampling signals.

[0086] Step 206: normalize the IQ sampling signals to obtain a feedback signal in the form of a complex signal.

[0087] Step 207: determine the second power according to the root mean square of the feedback signal.

[0088] Specifically, first, the root mean square of the feedback signal is calculated by the root mean square formula of the feedback signal; the root mean square formula of the feedback signal includes: Where rms(y(n)) represents the root mean square of the feedback signal, y n is the value of the nth feedback signal sample point, and N is the total number of signal samples.

[0089] Then, the second power of the feedback signal is calculated according to the signal power formula of the feedback signal; the signal power formula of the feedback signal includes: y power =20log 10 (rms(y(n))); Among them, x power represents the second power of the feedback signal.

[0090] Step 208: Calculate the amplitude difference between the feedback signal and the original signal according to the amplitude difference formula.

[0091] Specifically, the amplitude difference formula includes, G=x power / y power ; Among them, x power represents the first power, y power represents the second power. That is, the amplitude difference is the ratio of the first power to the second power.

[0092] By introducing the amplitude difference formula, a direct and systematic method is provided for calculating the amplitude difference between the feedback signal and the original signal. The amplitude difference formula explains how to calculate the amplitude difference based on the first power and the second power, including the mathematical expression of the amplitude difference and the definition of related parameters. This method not only provides a fast and accurate means of evaluating the amplitude difference, but also ensures the consistency and repeatability of the amplitude difference calculation by clarifying the relationship between the first power and the second power. This is crucial for subsequent signal amplitude alignment adjustments because it directly affects the effect of signal compensation and the overall performance of the communication system. With this method, the nonlinear effects of the power amplifier can be more effectively predicted and compensated, thereby optimizing signal quality and system efficiency.

[0093] Step 209: determine the amplitude alignment signal according to the signal difference formula.

[0094] The signal difference formula is used to represent the amplitude difference between the feedback signal and the original signal. The signal difference formula includes: ; Among them, x(n) represents the AM signal corresponding to the original signal, y(n-τ) represents the value of the feedback signal before the time delay τ, G represents the amplitude difference, θ is the phase difference, and w is the frequency deviation.

[0095] Specifically, y(n-τ) represents the nth sample point of the feedback signal after considering the time delay τ; the time delay τ here represents the time offset that may occur during the propagation or processing of the signal; G is the amplitude difference, which is used as an amplitude compensation factor to adjust the amplitude of the feedback signal to match the amplitude of the original signal; e jθ is the phase compensation factor, which is used to adjust the phase of the feedback signal to compensate for possible phase distortion; e jwn is the frequency compensation factor, w represents the frequency deviation, which is used to adjust the frequency deviation of the signal, and n is the sample point number; the frequency compensation factor takes into account the frequency offset that may occur in the signal during the amplification process.

[0096] The signal difference formula indicates that in order to make the feedback signal y(n-τ) match the original signal x(n), the feedback signal needs to be compensated for amplitude, phase and frequency.

[0097] This compensation is a key step in the DPD algorithm of this embodiment, and its purpose is to correct the distortion of the signal caused by nonlinear effects in the power amplifier. In this way, the quality of the signal can be significantly improved and the performance of the communication system can be optimized.

[0098] Step 210, determining a normalized mean square error (NMSE) between the feedback signal and the original signal.

[0099] Specifically, first, the sample square difference of the feedback signal and the original signal is calculated respectively, and the sum is divided by the signal length to obtain the mean square error (MSE). Next, the total power of the original signal is calculated, which can usually be obtained by taking the average of the square of the original signal samples. Then, the MSE is divided by the power of the original signal to obtain the normalized mean square error NMSE.

[0100] NMSE measures the closeness of the feedback signal to the original signal in amplitude. The lower the NMSE value, the smaller the signal distortion and the smaller the error between the feedback signal and the original signal, that is, the higher the similarity between the two, the better the compensation effect. If the NMSE exceeds the preset threshold, it may be necessary to resample the signal or adjust the compensation algorithm to improve the accuracy of signal processing. This process is a key step in evaluating and optimizing the performance of the digital pre-distortion (DPD) compensation method to ensure that the signal remains high quality after passing through the power amplifier and communication link.

[0101] Step 211, determining whether the normalized mean square error is greater than a set threshold.

[0102] If the normalized mean square error NMSE is greater than the set threshold, it indicates that the signal distortion is serious, the noise in the current sample value is too large, and it is not suitable for DPD calculation. Resampling is required, and the process returns to step 205 to resample the amplified signal.

[0103] This ensures that more accurate signal data is obtained so that the DPD algorithm can be adjusted or optimized to more effectively predict and compensate for the nonlinear distortion of the power amplifier. Through this iterative sampling and adjustment, the accuracy of signal compensation can be gradually improved until the NMSE is reduced to an acceptable range, ensuring the transmission quality of the signal and the overall performance of the communication system.

[0104] Figure 3 As an example, the comparison between the direct-sampled IQ two-way signal (IQ two-way sampled signal) and the original AM signal (original signal) before and after alignment is shown. Figure 3 It can be seen that the final compensated feedback signal y(n) and the original signal x(n) are aligned in amplitude, and the normalized mean square error (NMSE) between the two reaches -39.6dB.

[0105] If the threshold is set to 20dB, NMSE is -39.6<20dB, indicating that the error between the feedback signal y(n) after signal compensation and the original signal x(n) is very small, the two are highly similar, the signal is not overly distorted, and the signal loss is within the expected range.

[0106] If the normalized mean square error is less than or equal to the set threshold, the process proceeds to step 212 .

[0107] Step 212: Based on the delay of the original signal, perform delay alignment adjustment on the amplitude aligned signal to obtain an amplitude delay aligned signal.

[0108] This step refers to step 106 and will not be described in detail here.

[0109] By using the method of this embodiment, the input and output signals are amplitude aligned, and the DPD optimization effect is significant. The signal distortion can be optimized from 7% to less than 1%, the positive and negative peak imbalance is optimized from 10% to about 1%, and the carrier drop is optimized from 7% to less than 3%.

[0110] The DPD feedback signal gain compensation method proposed in this embodiment can effectively control and compensate the nonlinear effect of the power amplifier. In traditional communication systems, the nonlinear behavior of the power amplifier often leads to signal distortion, which reduces the quality of the signal, increases the bit error rate, and shortens the communication distance. However, using the method of this embodiment, the signal can be actively compensated in the digital domain before the signal is amplified to offset the distortion expected to be generated due to the nonlinear characteristics of the power amplifier.

[0111] Specifically, the method of this embodiment first involves accurately sampling and analog-to-digital conversion of the original signal to obtain two-way IQ sampling signals. These signals are then normalized and converted into feedback signals in the form of complex signals, providing a standardized signal format for subsequent processing steps. By comparing the root mean square (RMS) of the original signal and the feedback signal, the power difference between the two can be determined, and the amplitude difference can be evaluated accordingly. This evaluation is the key to achieving accurate compensation because it enables quantification of the amplitude changes that may occur in the signal after passing through the power amplifier.

[0112] Based on this evaluation, the method of this embodiment further performs amplitude alignment adjustment on the feedback signal to ensure that its amplitude is consistent with the original signal. In addition, delay alignment adjustment can also be performed to ensure the synchronization of the signal in time. Through these adjustments, a compensation signal is generated, which can accurately predict and compensate for the nonlinear effects of the power amplifier in digital form before the signal is amplified.

[0113] This compensation signal is applied to the original signal to obtain a pre-distortion compensated signal. After passing through the power amplifier, the amplitude and phase of the pre-distortion compensated signal can still maintain integrity close to the original signal, thereby significantly improving the transmission quality of the signal. This compensation not only reduces the distortion caused by nonlinearity, such as amplitude compression and spectrum expansion, but also improves the signal-to-noise ratio, reduces the bit error rate, and enhances the coverage and reliability of the communication system.

[0114] In addition, this method also includes a feedback loop to evaluate the compensation effect by calculating the normalized mean square error (NMSE). If the NMSE is greater than the set threshold, it means that the compensation effect does not meet the expectations, and the system will automatically resample and process the signal until the accuracy requirement is met. This adaptive mechanism further ensures the robustness and accuracy of the DPD compensation method.

[0115] In summary, the DPD feedback signal gain compensation method of this embodiment effectively solves the challenges brought by the nonlinear characteristics of the power amplifier through precise digital signal processing technology, and improves the overall performance of the wireless communication system. This method is not only applicable to traditional fields such as broadcasting, mobile communications and satellite communications, but also can adapt to the development of future communication technologies such as 5G and the Internet of Things (IoT), providing a solid technical foundation for achieving faster, more reliable and smarter communications.

[0116] The method provided in the above embodiment can be executed by an electronic device. The following describes the electronic device in the embodiment of the present invention from the perspective of hardware processing. Figure 4 , is a schematic diagram of a physical device structure of an electronic device in an embodiment of the present invention.

[0117] It should be noted that Figure 4 The structure of the electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0118] like Figure 4 As shown, the electronic device includes a central processing unit (CPU) 401, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 402 or the program loaded from the storage part 408 to the random access memory (RAM) 403, such as executing the method described in the above embodiment. In RAM 403, various programs and data required for system operation are also stored. CPU 401, ROM 402 and RAM 403 are connected to each other through bus 404. Input / output (I / O) interface 405 is also connected to bus 404.

[0119] The following components are connected to the I / O interface 405: an input section 406 including an audio input device, a button switch, etc.; an output section 407 including a liquid crystal display (LCD) and an audio output device, an indicator light, etc.; a storage section 408 including a hard disk, etc.; and a communication section 409 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 409 performs communication processing via a network such as the Internet. A drive 410 is also connected to the I / O interface 405 as needed. A removable medium 411, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 410 as needed so that a computer program read therefrom is installed into the storage section 408 as needed.

[0120] In particular, according to an embodiment of the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part 409, and / or installed from the removable medium 411. When the computer program is executed by the central processing unit (CPU) 401, various functions defined in the present invention are performed.

[0121] It should be noted that specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device.

[0122] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. Each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of a code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from that marked in the accompanying drawings.

[0123] Specifically, the electronic device of this embodiment includes a processor and a memory, the memory is coupled to one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and one or more processors call the computer instructions to enable the electronic device to execute the method provided by the above embodiment.

[0124] As another aspect, the present invention further provides a computer-readable storage medium, which may be included in the electronic device described in the above embodiment; or may exist independently without being assembled into the electronic device. The above storage medium carries one or more computer programs, and when the above one or more computer programs are executed by a processor of the electronic device, the electronic device implements the method provided in the above embodiment.

[0125] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

[0126] As used in the above embodiments, the term "when..." may be interpreted to mean "if..." or "after..." or "in response to determining..." or "in response to detecting...", depending on the context. Similarly, the phrases "upon determining..." or "if (the stated condition or event) is detected" may be interpreted to mean "if determining..." or "in response to determining..." or "upon detecting (the stated condition or event)" or "in response to detecting (the stated condition or event)", depending on the context.

[0127] Those skilled in the art can understand that to implement all or part of the processes in the above-mentioned embodiments, the processes can be completed by computer programs to instruct related hardware, and the programs can be stored in computer-readable storage media. When the programs are executed, they can include the processes of the above-mentioned method embodiments. The aforementioned storage media include: ROM or random access memory RAM, magnetic disk or optical disk and other media that can store program codes.

Claims

1. A DPD feedback signal gain compensation method, characterized in that: include: After the original signal is amplified to form an amplified signal, the amplified signal is sampled and analog-to-digital converted to obtain two-way IQ sampling signals; Normalizing the IQ two-way sampling signal to obtain a feedback signal in the form of a complex signal; In the case where the first power is determined according to the root mean square of the original signal, the second power is determined according to the root mean square of the feedback signal; Determining an amplitude difference between the feedback signal and the original signal based on the first power and the second power; According to the amplitude difference and the amplitude of the original signal, the feedback signal is amplitude aligned to obtain an amplitude aligned signal; Based on the time delay of the original signal, a time delay alignment adjustment is performed on the amplitude alignment signal to obtain an amplitude delay alignment signal.

2. The method according to claim 1, characterized in that After the step of performing amplitude alignment adjustment on the feedback signal according to the amplitude difference and the amplitude of the original signal to obtain an amplitude aligned signal, the method further includes: Determining a normalized mean square error between the feedback signal and the original signal; If the normalized mean square error is greater than a set threshold, the amplified signal is resampled.

3. The method according to claim 1 or 2, characterized in that: Before the step of sampling and analog-to-digital conversion of the amplified signal to obtain IQ two-way sampling signals, the method includes: According to the AM modulation signal formula, the original signal is converted into the form of an AM signal, and the AM modulation signal formula includes: Wherein, x(n) represents the AM signal corresponding to the original signal, α is the modulation coefficient, f is the frequency, n is the signal sample point number, t is the time variable, and j is the imaginary unit.

4. The method according to claim 3, characterized in that The determining the first power according to the root mean square of the original signal comprises: The first power of the original signal is determined according to a signal power formula, wherein the signal power formula includes: x power =20log 10 (rms(x(n))); Among them, x power represents the first power of the original signal, and rms(x(n)) represents the root mean square of the original signal.

5. The method according to claim 4, characterized in that Before determining the first power according to the root mean square of the original signal, the method further comprises: The root mean square of the original signal is determined according to a signal root mean square formula, wherein the signal root mean square formula includes: Wherein, rms(x(n)) represents the root mean square of the original signal, x n is the value of the nth original signal sample point, and N is the total number of signal samples.

6. The method according to claim 3, characterized in that: The step of performing amplitude alignment adjustment on the feedback signal according to the amplitude difference and the amplitude of the original signal to obtain an amplitude aligned signal comprises: The amplitude alignment signal is determined according to a signal difference formula, wherein the signal difference formula is used to represent the amplitude difference between the feedback signal and the original signal, and the signal difference formula includes: ； Among them, x(n) represents the AM signal corresponding to the original signal, y(n-τ) represents the value of the feedback signal before the time delay τ, G represents the amplitude difference, θ is the phase difference, and w is the frequency deviation.

7. The method according to claim 6, characterized in that The step of determining the amplitude difference between the feedback signal and the original signal based on the first power and the second power comprises: The amplitude difference between the feedback signal and the original signal is calculated according to an amplitude difference formula, wherein the amplitude difference formula includes: G=x power / y power ; Among them, x power represents the first power, y power represents the second power.

8. An electronic device, characterized in that: including one or more processors and memory; The memory is coupled to the one or more processors, and the memory is used to store computer program codes, wherein the computer program codes include computer instructions, and the one or more processors call the computer instructions to enable the electronic device to execute the method according to any one of claims 1 to 7.

9. A computer-readable storage medium storing computer instructions, characterized in that: When the computer instructions are executed on an electronic device, the electronic device is caused to execute the method as claimed in any one of claims 1 to 7.

10. A computer program product, characterized in that When the computer program product is executed on an electronic device, the electronic device is enabled to execute the method according to any one of claims 1 to 7.

Images