IQ imbalance joint correction method and device for a multi-carrier signal

Abstract

The application relates to the technical field of radio frequency signal processing, and discloses an IQ imbalance joint correction method and device of a multi-carrier signal; wherein the method comprises the following steps: constructing an IQ imbalance model driven by a frequency mirror double channel; estimating imbalance parameters through a least square method and an LMS iteration; constructing a complex domain IQ compensation matrix to compensate each sub-carrier one by one; and outputting a corrected multi-carrier complex base signal in a frequency domain sequence. Compared with the prior art which only relies on a static IQ model or a single point compensation mode, especially in scenes where temperature drift exists on the terminal side, mirror frequency coupling is significant, and front-end gain dynamically changes, the technical problem that stable and effective full-band IQ joint correction cannot be realized is solved. Since the dynamic modeling mechanism driven by spectrum energy perception and mirror frequency leakage estimation is introduced, accurate tracking and low complexity deployment of time-varying IQ imbalance are realized, so that the multi-carrier signal demodulation precision and anti-interference ability are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of radio frequency signal processing technology, and in particular to a method and apparatus for joint correction of IQ imbalance in multi-carrier signals. Background Technology

[0002] Currently, in broadband wireless communication systems such as 5G NR and WiFi-7, to improve spectral efficiency and throughput, receivers typically employ a multi-carrier parallel processing architecture, where multiple subcarriers simultaneously carry independently modulated and demodulated signals. However, due to non-ideal factors in the RF receiver chain, such as analog-to-digital channel mismatch, local oscillator phase misalignment, and inconsistent frequency response of analog filters, asymmetry in amplitude and phase exists between IQ paths, resulting in IQ imbalance. This leads to problems such as enhanced image interference, constellation diagram distortion, and increased bit error rate. Especially at the terminal device end, limited by package size, power supply fluctuations, and temperature drift effects, the IQ imbalance parameters exhibit significant time-varying characteristics, exacerbating the degradation of signal demodulation accuracy. In existing technologies, one type of scheme uses a single-point estimation model based on reference symbols for static compensation, but it cannot adapt to rapidly changing temperature or path disturbance conditions and is difficult to maintain compensation accuracy over a long period. Another type of scheme constructs an image leakage estimation model based on higher-order moments or spectral symmetry, but lacks a modeling mechanism for frequency domain coupling between subcarriers, making it difficult to achieve joint suppression of IQ imbalance effects across the entire bandwidth.

[0003] Furthermore, in scenarios where terminal resources are limited, existing methods generally suffer from high computational complexity and poor real-time performance, making them difficult to deploy directly to low-power DSPs or embedded platforms.

[0004] Therefore, there is an urgent need for a multi-carrier IQ imbalance joint correction method that can dynamically track changes in imbalance parameters, has image-frequency coupling sensing capability, and is easy to embed into deployment, in order to improve the reception robustness and signal demodulation accuracy of multi-carrier systems in complex interference environments. Summary of the Invention

[0005] To address the aforementioned technical shortcomings, the purpose of this invention is to propose a joint IQ imbalance correction method for multi-carrier signals. This method aims to solve the technical problem that existing technologies rely solely on static IQ models or single-point compensation methods, which are particularly problematic in scenarios where there are temperature drift, significant image-frequency coupling, and dynamic changes in front-end gain at the terminal side, making it impossible to achieve stable and effective full-band IQ joint correction.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The present invention provides a method for joint correction of IQ imbalance in multi-carrier signals.

[0007] The IQ imbalance joint correction method for the multi-carrier signal includes:

[0008] Step S10: Obtain the set of multi-carrier complex base signals to be received, and for the first multi-carrier complex base signal in the set... Ideal input signal for each subcarrier An IQ imbalance model is constructed using a dual-channel drive mechanism of frequency mirrors. IQ Imbalance Model Output received observation signal;

[0009] Step S20: Based on the received observed signal and the preset known reference symbol, a polynomial complex domain residual is constructed using the least squares estimation method. Based on the complex domain residual, the imbalance parameter is dynamically updated using the LMS criterion iterative method, and the estimated value of the imbalance amplitude factor is output. and mirror coupling factor estimates ;

[0010] Step S30: Based on the estimated value of the imbalance amplitude factor and mirror coupling factor estimates A time-varying adaptive smoothing process is performed using an exponential sliding filter control mechanism driven by temperature drift sensing, and the first filtered imbalance coefficient is output. With the imbalance coefficient after the second filter ;

[0011] Step S40: Based on the imbalance coefficient after the first filtering With the imbalance coefficient after the second filter Construct a complex domain IQ linear compensation matrix, and apply the IQ linear compensation matrix to the ideal input signal. Perform matrix compensation operation and output the first... IQ imbalance complex domain correction signal of each subcarrier ;

[0012] Step S50: Aggregate and reconstruct the IQ imbalance complex domain correction signals corresponding to the subcarriers in the set of all multi-carrier complex base signals along the frequency domain direction to generate the final correction output signal.

[0013] Preferably, in step S10, the multi-carrier complex base signal set is used to represent the complex envelope signal received in the 5G mobile terminal via direct radio frequency down-conversion; the first in the multi-carrier complex base signal set... Each subcarrier corresponds to a center frequency point. and bandwidth .

[0014] Preferably, in step S10, for the first multi-carrier complex base signal set... Ideal input signal for each subcarrier An IQ imbalance model is constructed using a dual-channel drive mechanism of frequency mirrors. IQ Imbalance Model The steps for outputting the received observation signal specifically include:

[0015] First, construct the frequency domain energy aggregation factor. First, let's consider the first [number] signal in the multi-carrier complex base signal set. Ideal input signal for each subcarrier The ideal input signal is calculated within a preset sliding window length T. The short-time frequency domain statistical characteristics include the spectral mean. With spectral change Based on spectral mean With spectral change Constructing frequency domain energy aggregation factor Frequency domain energy aggregation factor Used to indicate the first The changes in the power characteristics of each subcarrier reflect whether there are changes in front-end gain, power fluctuations, or path switching events.

[0016] Then extract the image frequency interference coupling factor. : Then, regarding the first in the set of multi-carrier complex base signals The center frequency point of each subcarrier Perform FFT frequency domain sampling on the corresponding center frequency mirror frequency point to extract the main frequency power spectrum value. and image frequency leakage power spectrum value Based on the power spectral density of the main frequency and image frequency leakage power spectrum value Extracting image frequency interference coupling factor Image frequency interference coupling factor Used to measure the current level of mirror interference leakage;

[0017] Based on frequency domain energy aggregation factor and image frequency interference coupling factor Determine the first in the set of multicarrier complex base signals Each subcarrier corresponds to the IQ imbalance model The set of control parameters used includes the current modeling mode selection flag, the current imbalance parameter update activation flag, the initial value of the current estimation step size, and the IQ imbalance model. The final output is the received observation signal.

[0018] Preferably, in step S30, the imbalance amplitude factor is estimated. and mirror coupling factor estimates The steps for time-varying adaptive smoothing processing using a temperature drift sensing-driven exponential sliding filter control mechanism, and outputting the filtered imbalance coefficient, specifically include:

[0019] Step S301: Obtain the current temperature value Frequency domain energy aggregation factor And introduce time-varying tracking coefficients Based on the current temperature value and frequency domain energy aggregation factor Dynamically adjust time-varying tracking coefficients ;

[0020] Step S302: Based on time-varying tracking coefficients The imbalance magnitude factor was estimated using a first-order IIR exponential sliding structure. and mirror coupling factor estimates Perform time-varying adaptive smoothing processing and output filtered imbalance coefficients. The filtered imbalance coefficients include the first filtered imbalance coefficient. With the imbalance coefficient after the second filter .

[0021] Preferably, in step S30, the time-varying tracking coefficient is specifically:

[0022] ,in, This is the preset first steady-state fluctuation threshold corresponding to the frequency domain energy aggregation factor; This is the preset second steady-state fluctuation threshold corresponding to the frequency domain energy aggregation factor.

[0023] Preferably, in step S40, based on the first filtered imbalance coefficient... With the imbalance coefficient after the second filter Construct a complex domain IQ linear compensation matrix, and apply the IQ linear compensation matrix to the ideal input signal. Perform matrix compensation operation and output the first... IQ imbalance complex domain correction signal of each subcarrier The steps specifically include:

[0024] Based on the imbalance coefficient after the first filtering With the imbalance coefficient after the second filter Complex field IQ linear compensation matrix is ​​constructed using the complex field matrix mapping method. Among them, the complex domain IQ linear compensation matrix Used to describe amplitude and phase coupling distortion caused by IQ imbalance;

[0025] And based on the IQ linear compensation matrix, the ideal input signal Matrix compensation operations are performed using complex matrix multiplication to calculate the nth... IQ imbalance complex domain correction signal of each subcarrier .

[0026] Preferably, in step S40, the IQ linear compensation matrix is ​​stored in a preset double-ended register group to avoid asynchronous updates of the IQ linear compensation matrix during high-speed data channel transmission.

[0027] The present invention also provides a joint correction device for IQ imbalance of multi-carrier signals, comprising:

[0028] The observation modeling module is used to acquire the set of multi-carrier complex-based signals to be received, and to target the first multi-carrier complex-based signal in the set. Ideal input signal for each subcarrier An IQ imbalance model is constructed using a dual-channel drive mechanism of frequency mirrors. IQ Imbalance Model Output received observation signal;

[0029] The imbalance parameter estimation module is used to construct a polynomial-structured complex domain residual based on the received observed signal and a preset known reference symbol using the least squares estimation method. Based on the complex domain residual, the LMS criterion iterative method is used to dynamically update the imbalance parameters, outputting an estimated value of the imbalance amplitude factor. and mirror coupling factor estimates ;

[0030] The filtering and smoothing module is used to adjust the imbalance amplitude factor estimate. and mirror coupling factor estimates A time-varying adaptive smoothing process is performed using an exponential sliding filter control mechanism driven by temperature drift sensing, and the first filtered imbalance coefficient is output. With the imbalance coefficient after the second filter ;

[0031] The matrix compensation module is used to calculate the imbalance coefficient after the first filtering. With the imbalance coefficient after the second filter Construct a complex domain IQ linear compensation matrix, and apply the IQ linear compensation matrix to the ideal input signal. Perform matrix compensation operation and output the first... IQ imbalance complex domain correction signal of each subcarrier ;

[0032] The frequency domain reconstruction module is used to aggregate and reconstruct the IQ imbalance complex domain correction signals corresponding to the subcarriers in the set of all multi-carrier complex base signals along the frequency domain direction to generate the final correction output signal.

[0033] The present invention also provides a device for joint correction of IQ imbalance of multi-carrier signals, comprising: a memory, a processor, and a joint correction program for IQ imbalance of multi-carrier signals stored in the memory and executable on the processor. When the joint correction program for IQ imbalance of multi-carrier signals is executed by the processor, a method for joint correction of IQ imbalance of multi-carrier signals is implemented.

[0034] The present invention also provides a computer program product, including a joint correction program for IQ imbalance of multi-carrier signals, wherein the joint correction program for IQ imbalance of multi-carrier signals implements the joint correction method for IQ imbalance of multi-carrier signals when executed by a processor.

[0035] The beneficial effects of this invention are as follows: By introducing a dynamic modeling mechanism driven by dual-channel frequency mirrors, and combining parameter iteration and temperature drift sensing filtering control under the LMS criterion, this invention can effectively track IQ imbalance changes caused by temperature drift, power fluctuations, and mirror-frequency coupling, improve the stability and real-time performance of IQ correction, and realize accurate modeling and parallel correction of time-varying IQ imbalance in multi-carrier broadband scenarios for 5G terminals.

[0036] This invention achieves parallel compensation and optimization of multi-carrier IQ imbalance through polynomial residual construction, complex domain matrix compensation, and frequency domain sequential loading mechanism. It significantly improves the demodulation accuracy and spectral purity of the broadband signal receiving link on the terminal side, and features low complexity and high deployability. It is compatible with terminal-level resource-constrained platforms such as FPGA or MCU. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a flowchart illustrating the first embodiment of a joint correction method for IQ imbalance in multi-carrier signals according to the present invention.

[0039] Figure 2 This is a schematic diagram comparing the IQ imbalance correction performance under temperature drift variation of the first embodiment of the IQ imbalance joint correction method for multi-carrier signals according to the present invention.

[0040] Figure 3 This is a schematic diagram comparing the spectrum before and after IQ imbalance correction of a multi-carrier signal according to a first embodiment of the IQ imbalance joint correction method of the present invention.

[0041] Figure 4This is a schematic diagram of the device for a combined IQ imbalance correction method for multi-carrier signals according to the present invention. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Example 1: As Figure 1 The diagram shown is a flowchart of the first embodiment of the IQ imbalance joint correction method for multi-carrier signals of the present invention, which presents the first embodiment of the IQ imbalance joint correction method for multi-carrier signals of the present invention.

[0044] In the first embodiment, the IQ imbalance joint correction method for the multi-carrier signal includes:

[0045] Step S10: Obtain the set of multi-carrier complex base signals to be received, and for the first multi-carrier complex base signal in the set... Ideal input signal for each subcarrier An IQ imbalance model is constructed using a dual-channel drive mechanism of frequency mirrors. IQ Imbalance Model Output received observation signal;

[0046] It should be noted that the "dual-channel drive mechanism" refers to the simultaneous consideration of the main frequency component of the target subcarrier and its corresponding image frequency component during the IQ imbalance modeling process, in order to construct a signal representation with complex domain coupling characteristics. This mechanism mainly includes two paths: the main channel input and the image channel input, which are used to reflect the amplitude imbalance and image frequency interference leakage problems caused by factors such as mixing nonlinearity, gain inconsistency, and phase shift in the actual receiving path, thereby enabling the IQ imbalance model to accurately characterize the non-ideal effects caused by actual hardware and software mismatch.

[0047] Understandably, by introducing a dual-channel drive mechanism for the frequency mirror, the constructed IQ imbalance model can accurately characterize the complex domain coupling relationship between the main frequency signal and the mirror interference signal at the current subcarrier frequency point, providing a highly reliable observation data basis for the subsequent accurate estimation and dynamic compensation of the imbalance coefficient, thereby significantly enhancing the modeling adaptability and convergence stability of the IQ compensation link.

[0048] It should be understood that, compared to the static IQ model established based on only a single main channel signal in the existing technology, this dual-channel drive mechanism of the frequency mirror can continuously capture the characteristics of IQ imbalance evolving over time in complex scenarios such as temperature drift, inconsistent channel attenuation, and dynamic changes in the RF front end, and can reflect the dynamic impact of mirror frequency leakage.

[0049] For example, in a simulation experiment of a typical 8-carrier parallel transmission system, the temperature was slowly drifted between 35°C and 75°C, while a simulated front-end image frequency crosstalk amplitude of -28dB was introduced. The root mean square error (RMSE) of the traditional single-channel model in the presence of image frequency interference can reach over 0.18, while the IQ model constructed using the dual-channel driving mechanism of the image frequency interference described in this invention maintains an RMSE stably below 0.06 under the same conditions, and the bit error rate after compensation is reduced from 2.1×10⁻⁶. -3 Reduced to 4.6×10 -4 This verifies the efficient modeling capability and compensation accuracy of this step in complex wireless environments.

[0050] Step S20: Based on the received observed signal and the preset known reference symbol, a polynomial complex domain residual is constructed using the least squares estimation method. Based on the complex domain residual, the imbalance parameter is dynamically updated using the LMS criterion iterative method, and the estimated value of the imbalance amplitude factor is output. and mirror coupling factor estimates ;

[0051] It should be noted that "polynomial structure complex domain residual" refers to the observation error function represented in the complex domain, which establishes a complex coefficient polynomial model with respect to the imbalance amplitude factor and the mirror coupling factor, and is used to characterize the primary mirror frequency coupling error caused by IQ imbalance.

[0052] Understandably, by introducing a complex-domain polynomial structure residual modeling method and then using the LMS (Least Mean Square) criterion to perform adaptive iterative updates, not only can the convergence and stability of the parameter estimation process be guaranteed, but the imbalance factor can also be continuously optimized under rapidly changing wireless channel conditions, thereby achieving dynamic tracking of time-varying imbalance characteristics. Compared with conventional fixed-window estimation, the LMS iterative method has stronger real-time performance and lower computational complexity.

[0053] It should be understood that traditional IQ imbalance correction methods often employ one-time estimation or static compensation, making it difficult to maintain correction accuracy in complex scenarios with severe RF temperature drift and uncertain image frequency interference intensity at the terminal side. This step, however, integrates residual-driven least squares modeling with the LMS criterion, preserving global approximation capability while enhancing local rapid adaptive response capability, thus solving the problems of "outdated estimation" and "frequency domain jitter amplification" of imbalance parameters in existing technologies.

[0054] For example, such as Figure 2 As shown, the performance comparison of IQ imbalance correction between the traditional static estimation method and the method of this invention (LMS + complex domain residual) under different RF temperature drift intensities (unit: dB) is illustrated. The horizontal axis represents the RF temperature drift intensity, and the vertical axis represents the bit error rate (BER). It can be clearly seen that the BER of the traditional method rises rapidly after the temperature drift intensity exceeds 2dB, and tends to saturate above 5dB, with the BER reaching about 0.006. This indicates that the traditional static compensation method cannot respond in time when the RF characteristics change rapidly, resulting in a significant deterioration in the BER. In contrast, the method of this invention, by introducing a complex domain residual structure and an LMS adaptive iteration mechanism, has strong temperature drift tracking capability and robustness. Even under a 10dB temperature drift condition, it can still stably control the BER below 0.002, which is significantly better than the traditional scheme. The experimental results verify that the method has a stronger IQ imbalance suppression capability in dynamically changing environments, and is especially suitable for broadband communication scenarios with higher requirements for link stability and BER control.

[0055] Step S30: Based on the estimated value of the imbalance amplitude factor and mirror coupling factor estimates A time-varying adaptive smoothing process is performed using an exponential sliding filter control mechanism driven by temperature drift sensing, and the first filtered imbalance coefficient is output. With the imbalance coefficient after the second filter ;

[0056] It should be noted that the "temperature drift sensing-driven exponential sliding filter control mechanism" refers to dynamically adjusting the weight parameters of the exponential sliding filter based on the real-time temperature change trend fed back by the RF front-end sensor, thereby achieving time-series smoothing of the imbalance factor estimation under sudden temperature drift scenarios. This is based on the imbalance amplitude factor estimate. and mirror coupling factor estimates The steps for time-varying adaptive smoothing processing using a temperature drift sensing-driven exponential sliding filter control mechanism, and outputting the filtered imbalance coefficient, specifically include:

[0057] Get the current temperature value and frequency domain energy aggregation factor And introduce time-varying tracking coefficients Based on the current temperature value and frequency domain energy aggregation factor Dynamically adjust time-varying tracking coefficients ;

[0058] Based on time-varying tracking coefficients The imbalance magnitude factor was estimated using a first-order IIR exponential sliding structure. and mirror coupling factor estimates Perform time-varying adaptive smoothing processing and output filtered imbalance coefficients. The filtered imbalance coefficients include the first filtered imbalance coefficient. With the imbalance coefficient after the second filter .

[0059] The time-varying tracking coefficients are as follows:

[0060] ,in, This is the preset first steady-state fluctuation threshold corresponding to the frequency domain energy aggregation factor; This is the preset second steady-state fluctuation threshold corresponding to the frequency domain energy aggregation factor.

[0061] Understandably, by introducing an exponentially weighted moving average filter that is correlated with temperature changes, not only can the drawbacks of traditional filtering methods, such as filter failure or estimation oscillation under strong temperature drift, be avoided, but the filtering sensitivity can also be adaptively adjusted according to the external environment, thereby ensuring the continuity and accuracy of coefficient estimation in the subsequent compensation matrix construction stage, especially in scenarios where the temperature of the RF front end, such as mobile terminals or industrial equipment, is prone to fluctuation.

[0062] It should be understood that most existing technologies use fixed-weight or fixed-window-length moving averages to smooth imbalance factor estimates, which makes it difficult to balance dynamism and stability, and is prone to coefficient jumps or filtering delays under drastic temperature drift. This step, by introducing the control concept of "temperature drift sensing and dynamic exponential weighting," substantially improves the environmental adaptability of the filter, enabling the imbalance estimate to converge quickly and remain stable even under drastic temperature changes, effectively solving the problems of "excessive lag" or "sudden response jumps" in traditional methods.

[0063] Step S40: Based on the imbalance coefficient after the first filtering With the imbalance coefficient after the second filter Construct a complex domain IQ linear compensation matrix, and apply the IQ linear compensation matrix to the ideal input signal. Perform matrix compensation operation and output the first... IQ imbalance complex domain correction signal of each subcarrier ;

[0064] It should be noted that the complex domain IQ linear compensation matrix refers to a two-dimensional complex matrix in the complex domain that maps the amplitude error of IQ imbalance and the image interference term through linear modeling. This matrix contains the main channel gain and the image channel coupling term. By left-multiplying the ideal baseband signal vector with this matrix, the image interference can be effectively reduced and the orthogonality of the original signal can be restored.

[0065] Understandably, this compensation matrix serves as the carrier for the equivalent inverse modeling of IQ imbalance. Its introduction allows the image frequency leakage term in the receiving path to be treated as a decoupled linear interference source, achieving separation of the primary mirror signal through matrix inversion. Compared to the traditional method of "separate amplitude and phase compensation," complex domain matrix compensation exhibits stronger stability and consistency in complex channels with high coupling strength and asymmetric phase offset, making it suitable for scenarios requiring independent compensation for each subcarrier in a multi-subcarrier structure.

[0066] It should be understood that traditional methods often use fixed coefficients for amplitude and phase compensation, neglecting the coupling effect of IQ imbalance on the mirror subcarrier. This can cause inter-carrier crosstalk, especially in OFDM structures, leading to a deterioration in the bit error rate. This step, however, constructs a dynamically updated complex-domain linear compensation matrix and performs vector compensation operations on a subcarrier-by-subcarrier basis in the frequency domain. This decouples image frequency interference from the matrix structure, enhances the ability to resist image frequency leakage and cross-coupling, and improves the overall spectral purity and bit error rate robustness.

[0067] Step S50: Aggregate and reconstruct the IQ imbalance complex domain correction signals corresponding to the subcarriers in the set of all multi-carrier complex base signals along the frequency domain direction to generate the final correction output signal.

[0068] It should be noted that "frequency domain directional aggregation and reconstruction" refers to sequentially splicing or restoring subcarriers according to their subcarrier numbers or frequency positions in the spectrum after completing IQ imbalance compensation for each subcarrier, forming a continuous complex baseband multicarrier signal. This reconstruction operation must maintain the consistency of the frequency domain arrangement and phase continuity of each subcarrier to ensure orthogonality is maintained in the subsequent IDFT / FFT demodulation process and prevent compensation errors from propagating between frequency domains.

[0069] Understandably, this step integrates multiple independently IQ-corrected subcarrier signals into a unified frequency-domain data structure through frequency-domain splicing and reconstruction, constructing a complete complex baseband symbol frame. This provides a highly consistent, low-distortion signal foundation for subsequent demodulation and synchronization operations. This design not only enhances the flexibility of the modular compensation structure but also facilitates the hardware implementation of parallel processing architectures.

[0070] It should be understood that traditional methods often involve uniformly compensating the entire OFDM frame in the time domain or using image frequency filtering for coarse processing, which can easily lead to cross-interference between subcarriers. This is especially true in scenarios where the IQ imbalance parameters have strong frequency correlation or where image frequency coupling is nonlinearly enhanced, resulting in problems such as spectral leakage and sideband distortion. In contrast, this step adopts a processing path of uniform frequency domain stitching after subcarrier-by-subcarrier compensation, effectively isolating the source of frequency domain imbalance interference and preserving the signal-to-noise gain of each subcarrier to the greatest extent, which helps improve the frequency domain equalization and carrier recovery performance in subsequent links.

[0071] For example, such as Figure 3 As shown, the figure illustrates the comparison of frequency domain amplitude before and after performing IQ imbalance compensation in the subcarrier domain using the method of this invention under conditions of RF temperature drift and other disturbances. The red curve in the figure represents the frequency domain amplitude distribution of the signal before correction, exhibiting significant image-frequency leakage coupling, amplitude asymmetry, and strong inter-subcarrier interference. The blue curve represents the final signal amplitude after subcarrier-by-subcarrier compensation and frequency domain splicing reconstruction using the method of this invention, showing a flatter and more symmetrical distribution with significantly reduced amplitude jitter. This indicates that the method still possesses strong IQ correction robustness and spectrum recovery capability under high temperature drift disturbances.

[0072] Example 2: Furthermore, the present invention provides a multi-carrier signal IQ imbalance joint correction device, which employs a multi-carrier signal IQ imbalance joint correction method from the above embodiments, and can solve the technical problem of multi-carrier signal IQ imbalance joint correction. Compared with the prior art, the beneficial effects of the multi-carrier signal IQ imbalance joint correction device provided by the present invention are the same as the beneficial effects of the multi-carrier signal IQ imbalance joint correction method from the above embodiments, and other technical features in the multi-carrier signal IQ imbalance joint correction device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0073] Example 3: This invention provides a joint correction device for IQ imbalance of multi-carrier signals. Please refer to... Figure 4A multi-carrier signal IQ imbalance joint correction device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, which, when executed by the at least one processor, enable the at least one processor to perform the multi-carrier signal IQ imbalance joint correction method described in Embodiment 1 above. The multi-carrier signal IQ imbalance joint correction device in this embodiment may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital radio receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Description), PMPs (Portable Media Players), and in-vehicle terminals (e.g., in-vehicle navigation terminals), as well as fixed terminals such as digital TVs and desktop computers. This multi-carrier signal IQ imbalance joint correction device is merely an example and should not limit the functionality or scope of the embodiments of this invention. A multi-carrier signal IQ imbalance joint correction device may include a processing unit 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that can perform various appropriate actions and processes according to a program stored in a read-only memory 1002 or a program loaded from a storage device 1003 into a random access memory 1004. The random access memory 1004 also stores various programs and data required for the operation of the multi-carrier signal IQ imbalance joint correction device. The processing unit 1001, the read-only memory 1002, and the random access memory 1004 are interconnected via a bus 1005. An I / O interface 1006 is also connected to the bus. Typically, the following devices can be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 1003 including, for example, magnetic tape, hard disk, etc.; and communication devices 1009. Communication device 1009 allows a multi-carrier signal IQ imbalance joint correction device to communicate wirelessly or wiredly with other devices to exchange data. Although the figure shows a multi-carrier signal IQ imbalance joint correction device with various devices, it should be understood that it is not required to implement or possess all of the shown devices. More or fewer devices may be implemented alternatively.

[0074] Example 4: This invention also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the above-described method for joint correction of IQ imbalance in a multi-carrier signal. The computer program product provided by this invention can solve the technical problem of joint correction of IQ imbalance in a multi-carrier signal. Compared with the prior art, the beneficial effects of the computer program product provided by this invention are the same as those of the joint correction method for IQ imbalance in a multi-carrier signal provided in the above embodiments, and will not be repeated here.

[0075] In particular, according to the embodiments disclosed in this invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this invention include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from read-only memory 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this invention.

[0076] It should be understood that the various parts disclosed in this invention can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0077] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for joint correction of IQ imbalance in multi-carrier signals, characterized in that, The methods include: Step S10: Obtain the set of multi-carrier complex base signals to be received, and for the first multi-carrier complex base signal in the set... Ideal input signal for each subcarrier An IQ imbalance model is constructed using a dual-channel drive mechanism of frequency mirrors. IQ Imbalance Model Output received observation signal; Step S20: Based on the received observed signal and the preset known reference symbol, a polynomial complex domain residual is constructed using the least squares estimation method. Based on the complex domain residual, the imbalance parameter is dynamically updated using the LMS criterion iterative method, and the estimated value of the imbalance amplitude factor is output. and mirror coupling factor estimates ; Step S30: Based on the estimated value of the imbalance amplitude factor and mirror coupling factor estimates A time-varying adaptive smoothing process is performed using an exponential sliding filter control mechanism driven by temperature drift sensing, and the first filtered imbalance coefficient is output. With the imbalance coefficient after the second filter ; Step S40: Based on the imbalance coefficient after the first filtering With the imbalance coefficient after the second filter Construct a complex domain IQ linear compensation matrix, and apply the IQ linear compensation matrix to the ideal input signal. Perform matrix compensation operation and output the first... IQ imbalance complex domain correction signal of each subcarrier ; Step S50: Aggregate and reconstruct the IQ imbalance complex domain correction signals corresponding to the subcarriers in the set of all multi-carrier complex base signals along the frequency domain direction to generate the final correction output signal.

2. The method for joint IQ imbalance correction of multi-carrier signals as described in claim 1, characterized in that, In step S10, the multi-carrier complex base signal set is used to represent the complex envelope signal received in the 5G mobile terminal via direct radio frequency down-conversion; the first in the multi-carrier complex base signal set... Each subcarrier corresponds to a center frequency point. and bandwidth .

3. The method for joint IQ imbalance correction of multi-carrier signals as described in claim 1, characterized in that, In step S10, for the first multi-carrier complex base signal set... Ideal input signal for each subcarrier An IQ imbalance model is constructed using a dual-channel drive mechanism of frequency mirrors. IQ Imbalance Model The steps for outputting the received observation signal specifically include: First, construct the frequency domain energy aggregation factor. First, let's consider the first [number] signal in the multi-carrier complex base signal set. Ideal input signal for each subcarrier The ideal input signal is calculated within a preset sliding window length T. The short-time frequency domain statistical characteristics include the spectral mean. With spectral change Based on spectral mean With spectral change Constructing frequency domain energy aggregation factor Frequency domain energy aggregation factor Used to indicate the first The changes in the power characteristics of each subcarrier reflect whether there are changes in front-end gain, power fluctuations, or path switching events. Then extract the image frequency interference coupling factor. : Then, regarding the first in the set of multi-carrier complex base signals The center frequency point of each subcarrier Perform FFT frequency domain sampling on the corresponding center frequency mirror frequency point to extract the main frequency power spectrum value. and image frequency leakage power spectrum value Based on the power spectral density of the main frequency and image frequency leakage power spectrum value Extracting image frequency interference coupling factor Image frequency interference coupling factor Used to measure the current level of mirror interference leakage; Based on frequency domain energy aggregation factor and image frequency interference coupling factor Determine the first in the set of multicarrier complex base signals Each subcarrier corresponds to the IQ imbalance model The set of control parameters used includes the current modeling mode selection flag, the current imbalance parameter update activation flag, the initial value of the current estimation step size, and the IQ imbalance model. The final output is the received observation signal.

4. The method for joint IQ imbalance correction of multi-carrier signals as described in claim 1, characterized in that, In step S30, based on the estimated value of the imbalance amplitude factor... and mirror coupling factor estimates The steps for time-varying adaptive smoothing processing using a temperature drift sensing-driven exponential sliding filter control mechanism, and outputting the filtered imbalance coefficient, specifically include: Step S301: Obtain the current temperature value and frequency domain energy aggregation factor And introduce time-varying tracking coefficients Based on the current temperature value and frequency domain energy aggregation factor Dynamically adjust time-varying tracking coefficients ; Step S302: Based on time-varying tracking coefficients The imbalance magnitude factor was estimated using a first-order IIR exponential sliding structure. and mirror coupling factor estimates Perform time-varying adaptive smoothing processing and output filtered imbalance coefficients. The filtered imbalance coefficients include the first filtered imbalance coefficient. With the imbalance coefficient after the second filter .

5. The method for joint IQ imbalance correction of multi-carrier signals as described in claim 4, characterized in that, In step S30, the time-varying tracking coefficient ,in, This is the preset first steady-state fluctuation threshold corresponding to the frequency domain energy aggregation factor; This is the preset second steady-state fluctuation threshold corresponding to the frequency domain energy aggregation factor.

6. The method for joint IQ imbalance correction of multi-carrier signals as described in claim 1, characterized in that, In step S40, based on the imbalance coefficient after the first filtering... With the imbalance coefficient after the second filter Construct a complex domain IQ linear compensation matrix, and apply the IQ linear compensation matrix to the ideal input signal. Perform matrix compensation operation and output the first... IQ imbalance complex domain correction signal of each subcarrier The steps specifically include: Based on the imbalance coefficient after the first filtering With the imbalance coefficient after the second filter Complex field IQ linear compensation matrix is ​​constructed using the complex field matrix mapping method. Among them, the complex domain IQ linear compensation matrix Used to describe amplitude and phase coupling distortion caused by IQ imbalance; And based on the IQ linear compensation matrix, the ideal input signal Matrix compensation operations are performed using complex matrix multiplication to calculate the nth... IQ imbalance complex domain correction signal of each subcarrier .

7. The method for joint correction of IQ imbalance in multi-carrier signals as described in claim 1, characterized in that, In step S40, the IQ linear compensation matrix is ​​stored in a preset double-ended register group to avoid asynchronous updates of the IQ linear compensation matrix during high-speed data channel transmission.

8. A joint correction device for IQ imbalance of a multi-carrier signal, applied to the joint correction method for IQ imbalance of a multi-carrier signal according to any one of claims 1 to 7, characterized in that, The IQ imbalance joint correction device for the multi-carrier signal includes: The observation modeling module is used to acquire the set of multi-carrier complex-based signals to be received, and to target the first multi-carrier complex-based signal in the set. Ideal input signal for each subcarrier An IQ imbalance model is constructed using a dual-channel drive mechanism of frequency mirrors. IQ Imbalance Model Output received observation signal; The imbalance parameter estimation module is used to construct a polynomial-structured complex domain residual based on the received observed signal and a preset known reference symbol using the least squares estimation method. Based on the complex domain residual, the LMS criterion iterative method is used to dynamically update the imbalance parameters, outputting an estimated value of the imbalance amplitude factor. and mirror coupling factor estimates ; The filtering and smoothing module is used to adjust the imbalance amplitude factor estimate. and mirror coupling factor estimates A time-varying adaptive smoothing process is performed using an exponential sliding filter control mechanism driven by temperature drift sensing, and the first filtered imbalance coefficient is output. With the imbalance coefficient after the second filter ; The matrix compensation module is used to calculate the imbalance coefficient after the first filtering. With the imbalance coefficient after the second filter Construct a complex domain IQ linear compensation matrix, and apply the IQ linear compensation matrix to the ideal input signal. Perform matrix compensation operation and output the first... IQ imbalance complex domain correction signal of each subcarrier ; The frequency domain reconstruction module is used to aggregate and reconstruct the IQ imbalance complex domain correction signals corresponding to the subcarriers in the set of all multi-carrier complex base signals along the frequency domain direction to generate the final correction output signal.

9. A device for joint correction of IQ imbalance in multi-carrier signals, characterized in that, The IQ imbalance joint correction device for multi-carrier signals includes: a memory, a processor, and a multi-carrier signal IQ imbalance joint correction program stored in the memory and executable on the processor. When the multi-carrier signal IQ imbalance joint correction program is executed by the processor, it implements a multi-carrier signal IQ imbalance joint correction method according to any one of claims 1 to 7.

10. A computer program product, characterized in that, The computer program product includes a joint correction program for IQ imbalance of multi-carrier signals, which, when executed by a processor, implements a joint correction method for IQ imbalance of multi-carrier signals according to any one of claims 1 to 7.

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