A method and apparatus for self-calibration of transmitter local oscillator leakage frequency shift

Abstract

This invention provides a transmitter local oscillator leakage frequency shift self-calibration method and apparatus. Based on the transmitter and feedback path architecture, an energy model is constructed; the energy model characterizes the relationship between the local oscillator leakage compensation value and the feedback path energy; based on the preset value of the local oscillator leakage compensation value and the least squares method, the parameter values ​​of each energy model parameter in the energy model are estimated; based on the energy model and the parameter values ​​of each energy model parameter, the optimal local oscillator leakage compensation value is calculated; the optimal local oscillator leakage compensation value is used to perform reverse compensation for local oscillator leakage in the transmitter. By using quadratic polynomial fitting and the least squares method, the computational complexity is reduced, rapid compensation estimation is achieved, the resistance to external interference is enhanced, and the system is ensured to operate stably under various environments. Furthermore, optimizing the digital compensation value effectively suppresses local oscillator leakage, improves the purity of the transmitted signal, and ensures the signal clarity and stability of the wireless communication link.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a transmitter local oscillator leakage frequency shift self-calibration method and apparatus. Background Technology

[0002] With the development of wireless communication technology, especially the increasing demand for high data rates, transmitter architecture design and optimization are crucial. Zero Intermediate Frequency (Zero-IF) architecture simplifies intermediate frequency processing and can directly convert signals, but it introduces the problem of Local Oscillator Leakage (LO leakage), which means that the local oscillator signal leaks into the received or feedback signal through a non-ideal channel, interfering with system operation.

[0003] To address the local oscillator (LO) leakage problem, common techniques include DC bias compensation. This involves adding an appropriate DC compensation signal to the transmitted signal to shift the LO signal frequency to the LO point, thereby eliminating interference caused by LO leakage. Furthermore, with advancements in modulation techniques, the widespread application of Orthogonal Frequency Division Multiplexing (OFDM) and higher-order modulation (such as 256 / 1024 / 4096 QAM) places higher demands on transmitter LO leakage. While OFDM technology improves spectral efficiency, it also increases the peak-to-average power ratio (PAPR), making the requirements for error vector amplitude more stringent when processing higher-order modulated signals. Simultaneously, due to the inherent frequency offset between the transmitting and receiving equipment, transmitter LO leakage can also introduce inter-carrier interference during reception, further emphasizing the importance of reducing LO leakage. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a transmitter local oscillator leakage frequency shift self-calibration method and apparatus to solve the problem of transmitter local oscillator leakage compensation.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0006] The first aspect of this invention discloses a transmitter local oscillator leakage frequency shift self-calibration method, the method comprising:

[0007] An energy model is constructed based on the architecture of the transmitter and feedback path; the energy model characterizes the relationship between the local oscillator leakage compensation value and the energy of the feedback path.

[0008] Based on the preset value of the local oscillator leakage compensation value and the least squares method, the parameter values ​​of each energy model parameter in the energy model are estimated.

[0009] Based on the energy model and the parameter values ​​of each of the energy model parameters, the optimal local oscillator leakage compensation value is calculated.

[0010] The transmitter is subjected to reverse compensation for local oscillator leakage using the optimal local oscillator leakage compensation value.

[0011] Preferably, the step of constructing the energy model based on the transmitter and feedback path includes:

[0012] Based on the transmitter architecture, construct a radio frequency signal model;

[0013] Based on the aforementioned RF signal model and feedback path architecture, a feedback path signal model is constructed.

[0014] Based on the feedback path signal model and the preset energy calculation method, the feedback path energy calculation model is determined; the feedback path energy calculation model contains unknown constants.

[0015] Based on the gain of the digital-to-analog converter in the transmitter, the target value of the unknown constant is determined; the target value of the unknown constant enables the feedback path energy calculated by the feedback path energy calculation model to reach the minimum value.

[0016] An energy model is constructed based on the energy calculation model of the feedback path and the target value of the unknown constant.

[0017] Preferably, the step of constructing the radio frequency signal model based on the transmitter architecture includes:

[0018] Set the original I-channel signal and original Q-channel signal transmitted by the baseband module in the transmitter to 0;

[0019] The compensation values ​​of the original I-channel signal and the original Q-channel signal are calculated using a digital DC compensation module to obtain the I-channel compensated digital signal and the Q-channel compensated digital signal.

[0020] The I-channel compensated digital signal and the Q-channel compensated digital signal are converted into I-channel analog baseband signal and Q-channel analog baseband signal by a digital-to-analog converter;

[0021] The I-channel analog baseband signal and the Q-channel analog baseband signal are input into the upconverter in the transmitter architecture. The I-channel analog baseband signal and the Q-channel analog baseband signal are orthogonally modulated and added according to the local oscillator signal of the upconverter to obtain the initial radio frequency signal.

[0022] The initial radio frequency signal is amplified using a power amplifier to obtain a radio frequency signal model under mathematical conditions.

[0023] Preferably, the construction of the feedback path signal model based on the radio frequency signal model and the feedback path architecture includes:

[0024] Obtain the local oscillator signal of the downconverter from the architecture of the feedback path;

[0025] The radio frequency signal model is multiplied by the cos and sin components of the local oscillator signal to obtain the first and second initial baseband analog signals of the feedback path.

[0026] Substituting the complete expression of the radio frequency signal model into the formulas of the first initial baseband analog signal and the second initial baseband analog signal, the high-frequency components of the signal in the frequency domain are filtered out by the low-pass filter in the feedback path architecture, and the gain of the transmit path and the gain of the feedback path are combined to construct the feedback path signal model.

[0027] Preferably, the local oscillator leakage compensation value includes: I-channel local oscillator leakage compensation value and Q-channel local oscillator leakage compensation value;

[0028] The parameter values ​​of each energy model parameter in the energy model are estimated using the preset value of the local oscillator leakage compensation value and the least squares method, including:

[0029] Take either the I-channel local oscillator leakage compensation value or the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value;

[0030] Obtain multiple preset values ​​for the target local oscillator leakage compensation value;

[0031] For each preset value of the target local oscillator leakage compensation value, a feedback signal is collected on the feedback path, and the corresponding target feedback path energy is calculated based on the feedback signal;

[0032] Based on each preset value of the target local oscillator leakage compensation value, the energy of each target feedback path, and the least squares method, the parameter values ​​of each first parameter are calculated.

[0033] Take the other of the I-channel local oscillator leakage compensation value and the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value, and return to the step of obtaining multiple preset values ​​of the target local oscillator leakage compensation value to obtain the parameter values ​​of each second parameter;

[0034] The parameter values ​​of each of the first parameters and each of the second parameters are used as the parameter values ​​of each energy model parameter in the energy model.

[0035] A second aspect of the present invention discloses a transmitter local oscillator leakage frequency shift self-calibration device, the device comprising:

[0036] A construction unit is used to construct an energy model based on the architecture of the transmitter and feedback path; the energy model characterizes the relationship between the local oscillator leakage compensation value and the energy of the feedback path.

[0037] The estimation unit is used to estimate the parameter values ​​of each energy model parameter in the energy model based on the preset value of the local oscillator leakage compensation value and the least squares method.

[0038] The calculation unit is used to calculate the optimal local oscillator leakage compensation value based on the energy model and the parameter values ​​of each of the energy model parameters;

[0039] The self-calibration unit is used to perform reverse compensation for local oscillator leakage of the transmitter using the optimal local oscillator leakage compensation value.

[0040] Preferably, the building unit includes:

[0041] The first building module is used to build a radio frequency signal model based on the transmitter architecture;

[0042] The second building module is used to build a feedback path signal model based on the radio frequency signal model and the architecture of the feedback path;

[0043] The first determining module is used to determine the feedback path energy calculation model based on the feedback path signal model and the preset energy calculation method; the feedback path energy calculation model contains unknown constants;

[0044] The second determining module is used to determine the target value of the unknown constant based on the gain of the digital-to-analog converter in the transmitter; the target value of the unknown constant enables the feedback path energy calculated by the feedback path energy calculation model to reach the minimum value.

[0045] The third construction module is used to construct an energy model based on the energy calculation model of the feedback path and the target value of the unknown constant.

[0046] Preferably, the first building module includes:

[0047] The configuration submodule is used to set the original I-channel signal and the original Q-channel signal transmitted by the baseband module in the transmitter to 0;

[0048] The first calculation submodule is used to calculate the compensation values ​​of the original I-channel signal and the original Q-channel signal using the digital DC compensation module, so as to obtain the I-channel compensated digital signal and the Q-channel compensated digital signal.

[0049] The conversion submodule is used to convert the I-channel compensated digital signal and the Q-channel compensated digital signal into an I-channel analog baseband signal and a Q-channel analog baseband signal through a digital-to-analog converter;

[0050] The modulation submodule is used to input the I-channel analog baseband signal and the Q-channel analog baseband signal into the upconverter in the transmitter architecture, and to perform quadrature modulation on the I-channel analog baseband signal and the Q-channel analog baseband signal according to the local oscillator signal of the upconverter and add them together to obtain the initial radio frequency signal;

[0051] The amplification submodule is used to amplify the initial radio frequency signal using a power amplifier to obtain a radio frequency signal model under mathematical mode.

[0052] Preferably, the second building module includes:

[0053] The acquisition submodule is used to acquire the local oscillator signal of the downconverter from the architecture of the feedback path;

[0054] The second calculation submodule is used to multiply the radio frequency signal model by the cos component and sin component of the local oscillator signal respectively to obtain the first initial baseband analog signal and the second initial baseband analog signal of the feedback path;

[0055] A submodule is constructed to substitute the complete expression of the radio frequency signal model into the formulas of the first initial baseband analog signal and the second initial baseband analog signal, filter out the high-frequency components of the signal in the frequency domain through the low-pass filter in the feedback path architecture, and combine the gain of the transmit path and the gain of the feedback path to construct the feedback path signal model.

[0056] Preferably, the local oscillator leakage compensation value includes: I-channel local oscillator leakage compensation value and Q-channel local oscillator leakage compensation value;

[0057] The estimation unit includes:

[0058] The first marking module is used to take either the I-channel local oscillator leakage compensation value or the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value.

[0059] The acquisition module is used to acquire multiple preset values ​​of the target local oscillator leakage compensation value;

[0060] The first calculation module is used to collect feedback signals on the feedback path for each preset value of the target local oscillator leakage compensation value, and calculate the corresponding target feedback path energy based on the feedback signals.

[0061] The second calculation module is used to calculate the parameter values ​​of each first parameter based on each preset value of the target local oscillator leakage compensation value, the energy of each target feedback path, and the least squares method.

[0062] The return module is used to take the other of the I-channel local oscillator leakage compensation value and the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value, and return to the execution of the acquisition module to obtain the parameter values ​​of each second parameter;

[0063] The second marking module is used to take the parameter values ​​of each of the first parameters and the parameter values ​​of each of the second parameters as the parameter values ​​of each energy model parameter in the energy model.

[0064] This invention provides a transmitter local oscillator leakage frequency shift self-calibration method and apparatus based on the above embodiments. According to the transmitter and feedback path architecture, an energy model is constructed; the energy model characterizes the relationship between the local oscillator leakage compensation value and the feedback path energy; based on the preset value of the local oscillator leakage compensation value and the least squares method, the parameter values ​​of each energy model parameter in the energy model are estimated; based on the energy model and the parameter values ​​of each energy model parameter, the optimal local oscillator leakage compensation value is calculated; and the optimal local oscillator leakage compensation value is used to perform reverse compensation for local oscillator leakage in the transmitter. By transforming the problem into quadratic polynomial fitting and solving it using the least squares method, not only is the computational complexity significantly reduced, achieving fast and real-time compensation estimation and adjustment, but also the algorithm's resistance to external interference and internal noise is enhanced by introducing noise reduction processing and multiple measurement fitting mechanisms, ensuring stable and reliable operation of the system under various working environments. Simultaneously, optimizing the digital compensation value effectively suppresses local oscillator leakage introduced by analog hardware, significantly improving the purity and overall quality of the transmitted signal, thereby enhancing the performance and adaptability of the transmission system, which is of great value in ensuring the signal clarity and system stability of the wireless communication link. Attached Figure Description

[0065] 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 embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0066] Figure 1 Schematic diagrams of different local oscillator architectures for the transmitting circuit and feedback path provided in embodiments of the present invention;

[0067] Figure 2 This is a DC frequency domain schematic diagram of different local oscillator architectures for the transmitting circuit and feedback path provided in the embodiments of the present invention;

[0068] Figure 3 This is an architecture diagram of the radio frequency model of the transmitting circuit and feedback path provided in an embodiment of the present invention;

[0069] Figure 4A flowchart of a transmitter local oscillator leakage frequency shift self-calibration method provided in an embodiment of the present invention;

[0070] Figure 5 Another flowchart of a transmitter local oscillator leakage frequency shift self-calibration method provided in an embodiment of the present invention;

[0071] Figure 6 This is a structural block diagram of a transmitter local oscillator leakage frequency shift self-calibration device provided in an embodiment of the present invention. Detailed Implementation

[0072] 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.

[0073] In this application, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0074] As the background technology shows, common techniques for solving the local oscillator leakage problem include DC bias compensation. However, with the development of OFDM and higher-order modulation technology, the requirements for transmitter local oscillator leakage have also increased. This is because it not only affects the spectrum utilization and peak-to-average power ratio, but may also introduce inter-carrier interference during reception. Therefore, reducing local oscillator leakage is particularly important.

[0075] Therefore, this invention provides a transmitter local oscillator leakage frequency shift self-calibration method and apparatus. Based on the transmitter and feedback path architecture, an energy model is constructed; the energy model characterizes the relationship between the local oscillator leakage compensation value and the feedback path energy; based on the preset value of the local oscillator leakage compensation value and the least squares method, the parameter values ​​of each energy model parameter in the energy model are estimated; based on the energy model and the parameter values ​​of each energy model parameter, the optimal local oscillator leakage compensation value is calculated; the optimal local oscillator leakage compensation value is used to perform reverse compensation for local oscillator leakage in the transmitter. By transforming the problem into a quadratic polynomial fitting and solving it using the least squares method, not only is the computational complexity significantly reduced, achieving fast and real-time compensation estimation and adjustment, but the introduction of noise reduction processing and multiple measurement fitting mechanisms also enhances the algorithm's resistance to external interference and internal noise, ensuring stable and reliable operation of the system under various working environments. Simultaneously, optimizing the digital compensation value effectively suppresses local oscillator leakage introduced by analog hardware, significantly improving the purity and overall quality of the transmitted signal, thereby enhancing the performance and adaptability of the transmission system, which is of great value in ensuring the signal clarity and system stability of the wireless communication link.

[0076] See Figure 1 The diagram shows schematic diagrams of different local oscillator architectures for the transmitting circuit and feedback path provided in embodiments of the present invention.

[0077] Combination Figure 1 The diagram shows that by configuring two local oscillators f1 and f2 at different frequencies, the signal obtained in the feedback path, including the DC component of the feedback path and the frequency-shifted signal, can be expressed as TxDcImp×TxGain×FbGain×exp(j*2*pi*(f1-f2)*t)+FbDcImp. Here, "pi" represents π (approximately 3.14159). Since f1 and f2 are at different frequencies, the DC components of the transmit and feedback paths can be easily decoupled in the frequency domain, thereby improving system performance.

[0078] However, the DC component of the transmitter is related to time t, so it can only be determined by energy, calculated as PTx = |TxDcImp|² × |TxGain × FbGain|². To calculate the compensation value for the transmission path, parameters need to be adjusted to minimize PTx, i.e., PTx = |TxDcImp + TxDcComp|² × |TxGain × FbGain|². When PTx reaches its minimum, the compensation value TxDcComp = -TxDcImp can be obtained.

[0079] It should be noted that this algorithm needs to iterate through all possible values ​​to ensure that the minimum PTx is found. For example, in the DC compensation module, if both signals (I and Q) are 12 bits each, 8192 iterations are required, which consumes a significant amount of time. Furthermore, due to noise, PTx is not perfectly monotonic, which may cause the algorithm to converge to a local optimum. Therefore, see [link to relevant documentation]. Figure 2 The diagram shown illustrates the DC frequency domain of different local oscillator architectures for the transmitting circuit and feedback path.

[0080] In the feedback path analog-to-digital converter ( Figure 1 After the ADC shown, the frequency domain distribution of the obtained digital signal is as follows: Figure 2 As shown, PTxDcImpAdc and PFbDcImpAdc are separate in the frequency domain. Therefore, it is only necessary to find a suitable TxDcComp value that minimizes the value of PTxDcImpAdc. This chosen TxDcComp is the compensation value for the transmitter local oscillator leakage.

[0081] For details, see Figure 3 The diagram shows the architecture of the transmitter circuit and feedback path RF model. Based on this architecture, models of the ideal transmitter compensation value (TxDcComp) and the ideal transmitter local oscillator leakage residual energy (PTxDcImpAdc) are derived, realizing the transmitter local oscillator leakage frequency shift self-calibration method provided in this embodiment of the invention. See also Figure 4 The diagram illustrates a flowchart of a transmitter local oscillator leakage frequency shift self-calibration method provided by an embodiment of the present invention. The method includes:

[0082] Step S401: Construct an energy model based on the architecture of the transmitter and feedback path.

[0083] It should be noted that the energy model characterizes the relationship between the local oscillator leakage compensation value and the energy of the feedback path.

[0084] Understandably, the specific process of constructing the energy model based on the transmitter and feedback path architecture is as follows (processes A1 to A5):

[0085] Process A1: Based on the transmitter architecture, construct the radio frequency signal model.

[0086] In implementing process A1, based on the baseband in the transmitter (e.g.) Figure 3 The "Baseband" module transmits two signals (I-channel and Q-channel) to construct an RF signal model. The specific process is as follows (processes B1 to B5):

[0087] Process B1: Set the original I-channel signal and original Q-channel signal transmitted by the baseband module in the transmitter to 0.

[0088] Process B2: Calculate the compensation values ​​of the original I-channel signal and the original Q-channel signal using the digital DC compensation module to obtain the I-channel compensated digital signal and the Q-channel compensated digital signal.

[0089] It is understandable that digital DC compensation modules (such as...) can be used. Figure 3 The "DC Comp" shown calculates the compensation values ​​for the original I-channel signal and the original Q-channel signal, obtaining the I-channel compensated digital signal (i.e., ) and Q-channel compensated digital signal (i.e. ).

[0090] Process B3: Convert the I-channel compensated digital signal and the Q-channel compensated digital signal into the I-channel analog baseband signal and the Q-channel analog baseband signal using a digital-to-analog converter.

[0091] It should be noted that the digital-to-analog converter is... Figure 3 The "DAC" shown here has a digital-to-analog converter gain of . .

[0092] After implementing process B3, the output of the transmitter's DAC port is an analog signal, i.e. and .

[0093] Understandably, in the analog domain, local oscillator leakage mainly originates from the DC bias of the DAC and the self-mixing signal of the local oscillator, which can also be equivalently considered as analog signals. The transmitter's local oscillator leakage is primarily generated by these signals. In analog baseband, the leakage voltages of the two signals are represented as TxDcImpI and TxDcImpQ, respectively. The local oscillator signal is... .

[0094] The purpose of local oscillator leakage compensation is to make and As close to 0 as possible, where , and All of them are unknown constants.

[0095] Process B4: Input the I-channel analog baseband signal and the Q-channel analog baseband signal into the upconverter in the transmitter architecture. Based on the local oscillator signal of the upconverter, the I-channel analog baseband signal and the Q-channel analog baseband signal are quadrature modulated and added together to obtain the initial radio frequency signal.

[0096] In other words, the analog baseband signals from the I and Q channels are input to the upconverter in the transmitter architecture. The upconverter uses the local oscillator signal to quadrature-modulate the analog baseband signals from the I and Q channels, and then adds the two signals together to generate the initial radio frequency signal.

[0097] Process B5: The initial radio frequency signal is amplified using a power amplifier to obtain the radio frequency signal model under mathematical mode.

[0098] It is understandable that the formula for the radio frequency signal model is shown in formula (1).

[0099] (1)

[0100] In formula (1), This is a radio frequency signal model; For power amplifier gain; The local oscillator frequency of the inverter; It is a time signal.

[0101] Process A2: Based on the RF signal model and the architecture of the feedback path, construct the feedback path signal model.

[0102] In the specific implementation of process A2, the local oscillator signal of the downconverter is obtained from the architecture of the feedback path. Based on the local oscillator signal and RF signal model of the downconverter, the feedback path signal model is constructed. The specific process is as follows (processes C1 to C3):

[0103] Process C1: Obtain the local oscillator signal of the downconverter from the architecture of the feedback path.

[0104] In this embodiment, the feedback path is a signal acquisition and analysis path independent of the main transmission path. It should be noted that the local oscillator frequency of the downconverter is... And the local oscillator frequency of the inverter Not equal to the local oscillator frequency of the downconverter At this time, the frequency of the transmitter's local oscillator leakage is... The total gain of the feedback path is The local oscillator signal of the downconverter is and .

[0105] Process C2: Multiply the RF signal model by the cosine and sinine components of the local oscillator signal respectively to obtain the first initial baseband analog signal and the second initial baseband analog signal of the feedback path.

[0106] It is understandable that the radio frequency signal model respectively with and Multiplying these two orthogonal local oscillator signals yields a first initial baseband analog signal (as shown in Equation (2)) and a second initial baseband analog signal (as shown in Equation (3)) containing high-frequency and low-frequency components.

[0107] (2)

[0108] (3)

[0109] In formula (2), This is the first initial baseband analog signal; This is the second initial baseband analog signal.

[0110] Process C3: Substitute the complete expression of the RF signal model into the formulas of the first initial baseband analog signal and the second initial baseband analog signal. Use the low-pass filter in the feedback path architecture to filter out the high-frequency components of the signal in the frequency domain, and combine the gain of the transmit path and the gain of the feedback path to construct the feedback path signal model.

[0111] It is understandable that the radio frequency signal model Substituting the complete expression into the first initial baseband analog signal Second initial baseband analog signal The formula is expanded using trigonometric identities. Simultaneously, a low-pass filter in the feedback path architecture filters out high-frequency components, yielding low-frequency components. Furthermore, the gains of the transmit path and the feedback path are combined to obtain the total gain. Finally, a feedback path signal model is constructed based on the low-frequency components and the total gain.

[0112] It should be noted that the high-frequency components of the signal in the frequency domain are... The low-frequency component of the signal in the frequency domain is .

[0113] It is understandable that the power amplifier gain of the combined transmit path is... and total gain of feedback path , defined as total gain .

[0114] In the specific implementation process C3, based on low-frequency components and total gain Construct a feedback path signal model, as shown in formulas (4) to (6).

[0115] (4)

[0116] (5)

[0117] In formulas (4) and (5), It is related to the opening time of each feedback path and is an unknown constant.

[0118] It is understandable that formulas (4) and (5) will be used to... The data is converted to the digital domain by an ADC, as shown in formula (6).

[0119] (6)

[0120] In formula (6), This is a feedback path signal model. It represents the imaginary part of a complex number. For the numeric field . For the numeric field .

[0121] It should be noted that the feedback path signal model The included frequency is The single-tone signal and the DC signal of the feedback path with a frequency of 0.

[0122] Process A3: Based on the feedback path signal model and the preset energy calculation method, the feedback path energy calculation model is determined.

[0123] In implementing process A3, the feedback path signal model is decomposed, and based on the decomposition results and the preset energy calculation method, the feedback path energy calculation model is determined.

[0124] The feedback path signal model is decomposed to obtain the sum of two signals, i.e. As shown in formulas (7) and (8).

[0125]

[0126] (8)

[0127] In formula (7), It is the sampling interval. It is an unknown phase difference that exists.

[0128] It can be determined from formula (7) that and , and as well as It is related to the DC residue in the feedback path.

[0129] It should be noted that the calculation is based on a preset energy calculation method. energy Specifically, using The NCO downconverts the signal to 0, and the summation and energy calculation are shown in the following formula (9).

[0130] (9)

[0131] In formula (9), This is a feedback path energy calculation model, which includes unknown constants. . This represents the total gain. This refers to the gain of the digital-to-analog converter. It is a digital DC compensation module (such as) Figure 3 The I-channel compensated digital signal in "DC Comp" shown; Q is a digital DC compensation module (such as...) Figure 3 The Q-channel compensated digital signal in "DC Comp" shown.

[0132] Process A4: Determine the target value of the unknown constant based on the gain of the digital-to-analog converter in the transmitter.

[0133] It should be noted that the target value of the unknown constant can make the feedback path energy calculated by the feedback path energy calculation model reach the minimum value.

[0134] In other words, when and hour Minimum.

[0135] Process A5: Construct an energy model based on the feedback path energy calculation model and the target value of the unknown constant.

[0136] It should be noted that when , and When fixed, with For example, the derivation and The relationship is shown in formula (10).

[0137]

[0138] In formula (10), It is a digital DC compensation module (such as) Figure 3 The I-channel compensated digital signal in "DC Comp" shown; Q is a digital DC compensation module (such as...) Figure 3 The Q-channel compensated digital signal in "DC Comp" shown.

[0139] It can be determined from formula (10) and If the relationship is a quadratic polynomial in one variable, then remodeling is required. and The relationship is shown in formula (11).

[0140] (11)

[0141] Similarly, and The relationship is also a univariate quadratic polynomial, requiring remodeling. and The relationship is shown in formula (12).

[0142] (12)

[0143] Based on formulas (11) and (12), for about and Find the partial derivative; the extreme value is when the derivative is 0.

[0144] Therefore, it can be determined that when and hour Minimum.

[0145] Based on the above, the energy model is as follows: and .

[0146] It should be noted that, regarding , , and The calculation can be performed by selecting known... and To complete the task The measurements are then taken. Finally, these parameters are estimated using the least squares method, and the specific estimation process is described in step S402 below.

[0147] Understandably, due to It is a quadratic function for TxDcCompI and TxDcCompQ, and at least three measurements are required to estimate it. , , and Considering the impact of noise, multiple measurements can be performed to improve robustness and minimize the mean square error.

[0148] Step S402: Based on the preset value of the local oscillator leakage compensation value and the least squares method, estimate the parameter values ​​of each energy model parameter in the energy model.

[0149] It should be noted that the local oscillator leakage compensation value includes: the leakage compensation value of the I-channel local oscillator (i.e., ) and Q-channel local oscillator leakage compensation value ( ).

[0150] The specific process for implementing step S402 is as follows (processes D1 to D6):

[0151] Process D1: Take either the I-channel local oscillator leakage compensation value or the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value.

[0152] In some embodiments, the leakage compensation value of the I-channel local oscillator is used as the target local oscillator leakage compensation value, and the leakage compensation value of the Q-channel local oscillator is set to a constant.

[0153] For example: Set it to a constant, such as 0.

[0154] Process D2: Obtain multiple preset values ​​for the target local oscillator leakage compensation value.

[0155] It is understandable that multiple preset values ​​for the target local oscillator leakage compensation value form a set. That is to say, A set with N distinct elements. The value is N, where N>2, and N can be appropriately increased or decreased according to the actual chip emission system noise.

[0156] Specifically, a set of multiple preset values ​​for the target local oscillator leakage compensation value is formed. :{ , , ..., }

[0157] Process D3: For each preset value of the target local oscillator leakage compensation value, the feedback signal on the feedback path is collected, and the corresponding target feedback path energy is calculated based on the feedback signal.

[0158] In the specific implementation process D3, according to The number of feedback signals collected from the feedback path is used to calculate the corresponding target feedback path energy. , forming a set.

[0159] For example: :{ , , ..., }

[0160] Process D4: Based on each preset value of the local oscillator leakage compensation value of each target, the energy of each target feedback path, and the least squares method, the parameter values ​​of each first parameter are calculated.

[0161] When implementing process D4, according to and The least squares algorithm was used to estimate... , , The estimation algorithm is shown in formula (13).

[0162] (13)

[0163] It should be noted that, ;

[0164] .

[0165] Formula (13) can be rearranged as follows:

[0166] (14)

[0167] It is understandable that calculations are made based on ai and bi. .

[0168] Process D5: Take the other of the I-channel local oscillator leakage compensation value and the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value, and return to the step of obtaining multiple preset values ​​of the target local oscillator leakage compensation value to obtain the parameter values ​​of each second parameter.

[0169] It is understandable that the Q-channel local oscillator leakage compensation value is used as the target local oscillator leakage compensation value, and the I-channel local oscillator leakage compensation value is set as a constant.

[0170] For example: Set to a constant 0, or .

[0171] Get N different The value is N, where N>2, and N can be appropriately increased or decreased according to the actual chip emission system noise.

[0172] N different The values ​​form a set :{ , , ..., }

[0173] According to the set Collect and generate new feedback signal energy Similarly, in process D4, the following is estimated: , , .

[0174] Then according to , Calculate .

[0175] Process D6: Use the parameter values ​​of each first parameter and each second parameter as the parameter values ​​of each energy model parameter in the energy model.

[0176] Step S403: Based on the energy model and the parameter values ​​of each energy model parameter, calculate the optimal local oscillator leakage compensation value.

[0177] In the specific implementation step S403, based on the estimation using the least squares algorithm... , , and , The optimal local oscillator leakage compensation value was calculated. and .

[0178] Step S404: Perform reverse compensation for local oscillator leakage of the transmitter using the optimal local oscillator leakage compensation value.

[0179] In the specific implementation step S404, the optimal local oscillator leakage compensation value is... and The input is fed into the DC compensation module of the transmitter's digital baseband, whereby the DC compensation module will then use the optimal local oscillator leakage compensation value. and Real-time pre-compensation processing is performed on all transmitted signals passing through it, thereby completing the local oscillator leakage reverse compensation.

[0180] Understandably, the baseband signal emitted by the transmitter thereafter already incorporates these two precise compensation values ​​in the digital domain.

[0181] In this embodiment of the invention, by optimizing the digital compensation value, the local oscillator leakage introduced by the analog hardware is effectively suppressed, thereby significantly improving the purity of the transmitted signal and the overall signal quality. On one hand, the problem is transformed into a quadratic polynomial fitting problem, solved using the least squares method, which greatly reduces computational complexity, enabling the system to quickly and in real-time complete compensation estimation and adjustment. On the other hand, by introducing noise reduction processing and a multiple measurement fitting mechanism, the algorithm enhances its resistance to external interference and internal noise, ensuring stable and reliable operation under various working environments. In summary, this solution, through a model-driven optimization method, effectively improves the performance and adaptability of the transmission system, which is of great value for ensuring the signal clarity and system stability of wireless communication links.

[0182] In some embodiments, a single-frequency calibration signal can be generated, digitally pre-compensated, and then modulated by radio frequency before transmission. The signal is down-converted and digitized using independent feedback paths configured with different local oscillators to obtain a feedback digital signal. The image interference signal component corresponding to the frequency difference between the two local oscillators is extracted from this signal, and its energy value is calculated. Based on a preset model between this energy value and the digital pre-compensation parameters, a parameter estimation algorithm is used for fitting, directly solving for the optimal compensation parameters that minimize the energy. The obtained parameters are then configured back into the digital pre-compensation module, enabling rapid and accurate adaptive calibration of the transmitter's IQ imbalance, thus improving signal quality.

[0183] For details, see Figure 5 The content shown includes:

[0184] Step S501: Generate a calibration signal of a single frequency.

[0185] It should be noted that the calibration signal is a test signal used to evaluate and calibrate the transmitter performance.

[0186] In the specific implementation step S501, the calibration signal frequency is determined, wherein the calibration signal frequency is not equal to half of the local oscillator frequency difference between the transmission path and the feedback path; a calibration signal is generated based on the calibration signal frequency.

[0187] Optionally, the calibration signal may be generated by a digital signal processor or a dedicated waveform generation circuit, but is not limited to that generated by a digital signal processor or a dedicated waveform generation circuit. A single frequency refers to the signal exhibiting a single spectral line in the frequency domain, with its frequency component being a specific frequency point f0.

[0188] For example, the frequency point f0 of the calibration signal is not equal to half the difference between the local oscillator frequency f1 of the transmission path and the local oscillator frequency f2 of the feedback path. That is, the relationship f0 ≠ (f1 - f2) / 2 must be satisfied to ensure that the image interference component to be observed can be clearly separated in the future.

[0189] Step S502: Input the single-frequency calibration signal into the digital pre-compensation module of the transmission path for pre-compensation processing, and output the radio frequency signal after radio frequency modulation.

[0190] In this embodiment, the digital pre-compensation module receives the calibration signal as input and processes the signal in the digital domain according to pre-loaded compensation parameters to pre-adjust the amplitude and phase of the signal. The baseband signal after pre-compensation processing is then sent to the RF modulation unit. The RF modulation unit uses the local oscillator of the transmit path to up-convert the baseband signal to the RF band, thereby generating the final RF signal and outputting it through an antenna or test port. The digital pre-compensation processing is used to attempt to compensate for the inherent gain and phase imbalance, i.e., IQ imbalance, in the transmitter hardware link.

[0191] Specifically, the compensation parameters configured in the digital pre-compensation module include gain compensation parameters and phase compensation parameters.

[0192] Step S503: The radio frequency signal is down-converted and digitized through the feedback path to obtain the feedback digital signal.

[0193] In this embodiment, the feedback path is a signal acquisition and analysis path independent of the main transmission path. This path extracts a small portion of the radio frequency (RF) signal from the transmitter output via a coupler or directional coupling device. The extracted RF signal is then fed into the downconverter of the feedback path, which uses a local oscillator signal at a local oscillator frequency f2 to downconvert the RF signal to a lower intermediate frequency (IF) or directly to the baseband. Next, the downconverted analog signal is sampled and quantized by an analog-to-digital converter (ADC) to convert it into a feedback digital signal that can be processed by a digital signal processor (DSP).

[0194] Step S504: Extract the image interference signal component corresponding to the local oscillator frequency difference between the transmission path and the feedback path from the feedback digital signal, and calculate the energy value of the image interference signal component.

[0195] In this embodiment, because the transmit path and the feedback path use different local oscillator frequencies, the image interference component generated by the transmitter due to IQ imbalance will appear at a specific, predictable frequency position in the spectrum of the feedback digital signal. This position is determined by the formula f_image=f1-f0-f2 or f1+f0-f2, which is specifically a function related to the local oscillator frequency difference |f1-f2| and the calibration signal frequency f0.

[0196] Specifically, in the spectrum of the feedback digital signal, the signal component at the specific frequency f_image is located and separated; this component is defined as the image interference signal component. Extraction can be achieved in two ways, but not limited to: one is through digital down-conversion technology, using a digitally controlled oscillator to generate an orthogonal signal with frequency f_image, which is then mixed with the feedback digital signal and low-pass filtered; the other is by performing a fast Fourier transform on the feedback digital signal and directly reading the complex spectral value at that frequency point from the spectrum. After obtaining the time-domain or frequency-domain representation of the image interference signal component, its energy value needs to be calculated. The energy value is usually calculated by squaring and summing the amplitude of the component signal or by directly taking the square of its spectral amplitude.

[0197] In this embodiment, the energy value of the image interference signal component reflects the strength of the image interference remaining due to the transmitter IQ imbalance under the current compensation parameter configuration.

[0198] In the specific implementation step S504, the target frequency value is determined based on the local oscillator frequency of the transmission path, the frequency of the calibration signal, and the local oscillator frequency of the feedback path; the signal component with the target frequency value is separated from the feedback digital signal as the image interference signal component, and then the time-domain sampling sequence corresponding to the image interference signal component is obtained; the amplitude of each sampling point in the time-domain sampling sequence is squared to obtain the instantaneous power value of each sampling point.

[0199] In this embodiment, f1, f0, and f2 are calculated using a defined mathematical relationship. For example, this mathematical relationship can be expressed as f1-f0-f2 or its equivalent. Based on this method, the frequency position corresponding to the image interference component generated by the transmitter's IQ imbalance and ultimately manifested in the feedback digital baseband signal after two frequency conversions at different local oscillator frequencies can be accurately located in the frequency domain.

[0200] The feedback digital signal is a time-domain discrete digital sequence obtained after down-conversion and analog-to-digital conversion via a feedback path. It allows the extraction of narrowband signal components with concentrated energy at a target frequency value from a digital signal containing multiple frequency components.

[0201] In practice, this can be accomplished through various digital signal processing methods. One option is to utilize digital down-conversion technology: first, a quadrature digital local oscillator signal with the same frequency as the target frequency can be generated using a digitally controlled oscillator; then, the feedback digital signal is multiplied by the in-phase and quadrature components of this quadrature local oscillator signal; finally, the multiplied signal is low-pass filtered to remove high-frequency components and other frequency components far from the target frequency, ultimately yielding a complex baseband signal, which corresponds to the signal component at the target frequency value.

[0202] Another approach is based on spectrum analysis. Specifically, a fast Fourier transform can be performed on the feedback digital signal to convert it to the frequency domain and obtain the corresponding spectrum. The complex spectrum value on the frequency unit corresponding to the target frequency value can be directly located and read in the spectrum. This complex spectrum value represents the amplitude and phase information of the signal component with the target frequency value in the frequency domain. It can represent the separated signal component through inverse transformation or direct processing in the frequency domain.

[0203] In this embodiment, the time-domain sampling sequence refers to a set of time-discrete signal amplitude values ​​arranged at fixed time intervals, obtained after the operation of separating the image interference signal component from the feedback digital signal is completed. This sequence characterizes the instantaneous amplitude information of the image interference signal component as it changes over time.

[0204] Optionally, for the complex-form image interference signal component containing in-phase and quadrature components obtained through quadrature downconversion, the amplitude can be the magnitude of the complex sampling point, the square of which is equal to the sum of the squares of the in-phase component and the quadrature component, thus obtaining the instantaneous power value of each sampling point. The instantaneous power values ​​of all the sampling points are added together sequentially to obtain a total value, which is used as the energy value of the image interference signal component.

[0205] Step S505: Based on the preset relationship model between the energy value of the image interference signal component and the compensation parameters of the digital pre-compensation module, a parameter estimation algorithm is used to fit the model and solve for the target compensation parameters that minimize the energy value.

[0206] In this embodiment, a preset relationship model describes the mathematical relationship between the mirror interference energy value and the compensation parameter to be optimized.

[0207] Specifically, for a single-tone calibration signal, the relationship between the energy value and the compensation parameter can be modeled as a quadratic polynomial function of the compensation parameter. In practice, the compensation parameter configuration of the digital pre-compensation module can be changed step by step, while simultaneously acquiring the corresponding image interference energy value, thus obtaining multiple sets of observation data. Each set of observation data includes a compensation parameter and its corresponding energy value. Then, a parameter estimation algorithm, such as the least squares method, is used to fit these observation data into a preset relational model to estimate the specific coefficients of the model. Finally, by finding the extreme points through differentiation, the target compensation parameter that minimizes the model output value (i.e., the predicted energy value) is obtained. This effectively addresses the time-consuming search problem and overcomes the shortcomings of simple bisection methods, such as potentially getting trapped in local optima or being highly susceptible to noise interference.

[0208] Step S506: Configure the target compensation parameters into the digital pre-compensation module to perform signal calibration through the digital pre-compensation module configured with the target compensation parameters.

[0209] In this embodiment, the target compensation parameter is configured into the digital pre-compensation module. Subsequently, the digital pre-compensation module uses this target compensation parameter to perform real-time pre-compensation processing on all transmitted signals passing through it. In this way, the inherent IQ imbalance effect of the transmitter hardware is canceled in the digital domain, resulting in a lower image interference component in the final transmitted RF signal and improving the transmitter's signal quality.

[0210] Understandably, the application Figure 5 The method provided can also quickly and accurately achieve adaptive calibration of transmitter IQ imbalance, thereby improving signal quality.

[0211] Corresponding to the transmitter local oscillator leakage frequency shift self-calibration method provided in the above embodiments of the present invention, see also... Figure 6 The diagram shows a structural block diagram of a transmitter local oscillator leakage frequency shift self-calibration device provided in an embodiment of the present invention.

[0212] The device includes: a construction unit 601, an estimation unit 602, a calculation unit 603, and a self-calibration unit 604.

[0213] The building unit 601 is used to build an energy model based on the architecture of the transmitter and the feedback path; the energy model characterizes the relationship between the local oscillator leakage compensation value and the energy of the feedback path.

[0214] The estimation unit 602 is used to estimate the parameter values ​​of each energy model parameter in the energy model based on the preset value of the local oscillator leakage compensation value and the least squares method.

[0215] The calculation unit 603 is used to calculate the optimal local oscillator leakage compensation value based on the energy model and the parameter values ​​of each energy model parameter.

[0216] The self-calibration unit 604 is used to perform reverse compensation for local oscillator leakage of the transmitter using the optimal local oscillator leakage compensation value.

[0217] In this embodiment of the invention, by optimizing the digital compensation value, the local oscillator leakage introduced by the analog hardware is effectively suppressed, thereby significantly improving the purity of the transmitted signal and the overall signal quality. On one hand, the problem is transformed into a quadratic polynomial fitting problem, solved using the least squares method, which greatly reduces computational complexity, enabling the system to quickly and in real-time complete compensation estimation and adjustment. On the other hand, by introducing noise reduction processing and a multiple measurement fitting mechanism, the algorithm enhances its resistance to external interference and internal noise, ensuring stable and reliable operation under various working environments. In summary, this device effectively improves the performance and adaptability of the transmission system, and is of great value in ensuring the signal clarity and system stability of wireless communication links.

[0218] Combination Figure 6 The content shown, the construction unit 601, includes: a first construction module, a second construction module, a first determining module, a second determining module and a third construction module.

[0219] The first building module is used to construct an RF signal model based on the transmitter's architecture.

[0220] The second building module is used to construct the feedback path signal model based on the RF signal model and the feedback path architecture.

[0221] The first determining module is used to determine the feedback path energy calculation model based on the feedback path signal model and the preset energy calculation method; the feedback path energy calculation model contains unknown constants.

[0222] The second determining module is used to determine the target value of the unknown constant based on the gain of the digital-to-analog converter in the transmitter; the target value of the unknown constant can make the feedback path energy calculated by the feedback path energy calculation model reach the minimum value.

[0223] The third building module is used to construct an energy model based on the feedback path energy calculation model and the target value of the unknown constant.

[0224] Combination Figure 6 The content shown is the first building module, which includes: a setting submodule, a first calculation submodule, a conversion submodule, a modulation submodule, and an amplification submodule.

[0225] The configuration submodule is used to set the original I-channel and original Q-channel signals transmitted by the baseband module in the transmitter to 0.

[0226] The first calculation submodule is used to calculate the compensation values ​​of the original I-channel signal and the original Q-channel signal using the digital DC compensation module, so as to obtain the I-channel compensated digital signal and the Q-channel compensated digital signal.

[0227] The conversion submodule is used to convert the I-channel compensated digital signal and the Q-channel compensated digital signal into the I-channel analog baseband signal and the Q-channel analog baseband signal through a digital-to-analog converter.

[0228] The modulation submodule is used to input the I-channel analog baseband signal and the Q-channel analog baseband signal into the upconverter in the transmitter architecture. Based on the local oscillator signal of the upconverter, the I-channel analog baseband signal and the Q-channel analog baseband signal are orthogonally modulated and added together to obtain the initial radio frequency signal.

[0229] The amplification submodule is used to amplify the initial radio frequency signal using a power amplifier to obtain a radio frequency signal model under mathematical conditions.

[0230] Combination Figure 6 The content shown is the second building module, which includes: an acquisition submodule, a second calculation submodule, and a building submodule.

[0231] The acquisition submodule is used to acquire the local oscillator signal of the downconverter from the architecture of the feedback path.

[0232] The second calculation submodule is used to multiply the RF signal model by the cosine and sinine components of the local oscillator signal, respectively, to obtain the first initial baseband analog signal and the second initial baseband analog signal of the feedback path.

[0233] A submodule is constructed to substitute the complete expression of the RF signal model into the formulas of the first initial baseband analog signal and the second initial baseband analog signal. The high-frequency components of the signal in the frequency domain are filtered out by the low-pass filter in the feedback path architecture, and the gain of the transmit path and the gain of the feedback path are combined to construct the feedback path signal model.

[0234] Combination Figure 6 The local oscillator leakage compensation values ​​shown include: I-channel local oscillator leakage compensation value and Q-channel local oscillator leakage compensation value.

[0235] The estimation unit includes: a first marking module, an acquisition module, a first calculation module, a second calculation module, a return module, and a second marking module.

[0236] The first marking module is used to select either the I-channel local oscillator leakage compensation value or the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value.

[0237] The acquisition module is used to acquire multiple preset values ​​for the target local oscillator leakage compensation value.

[0238] The first calculation module is used to collect feedback signals on the feedback path for each preset value of the target local oscillator leakage compensation value, and calculate the corresponding target feedback path energy based on the feedback signals.

[0239] The second calculation module is used to calculate the parameter values ​​of each first parameter based on each preset value of the local oscillator leakage compensation value of each target, the energy of each target feedback path, and the least squares method.

[0240] The return module is used to take the other of the I-channel local oscillator leakage compensation value and the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value, and return to the execution acquisition module to obtain the parameter values ​​of each second parameter.

[0241] The second marking module is used to take the parameter values ​​of each first parameter and each second parameter as the parameter values ​​of each energy model parameter in the energy model.

[0242] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0243] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0244] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A transmitter local oscillator leakage frequency shift self-calibration method, characterized in that, The method includes: An energy model is constructed based on the architecture of the transmitter and feedback path; the energy model characterizes the relationship between the local oscillator leakage compensation value and the energy of the feedback path. Based on the preset value of the local oscillator leakage compensation value and the least squares method, the parameter values ​​of each energy model parameter in the energy model are estimated. Based on the energy model and the parameter values ​​of each of the energy model parameters, the optimal local oscillator leakage compensation value is calculated. The transmitter is subjected to reverse compensation for local oscillator leakage using the optimal local oscillator leakage compensation value; The step of constructing the energy model based on the transmitter and feedback path includes: Based on the transmitter architecture, construct a radio frequency signal model; Based on the aforementioned RF signal model and feedback path architecture, a feedback path signal model is constructed. Based on the feedback path signal model and the preset energy calculation method, the feedback path energy calculation model is determined; the feedback path energy calculation model contains unknown constants. Based on the gain of the digital-to-analog converter in the transmitter, the target value of the unknown constant is determined; the target value of the unknown constant enables the feedback path energy calculated by the feedback path energy calculation model to reach the minimum value. An energy model is constructed based on the energy calculation model of the feedback path and the target value of the unknown constant; The local oscillator leakage compensation value includes: I-channel local oscillator leakage compensation value and Q-channel local oscillator leakage compensation value; The parameter values ​​of each energy model parameter in the energy model are estimated using the preset value of the local oscillator leakage compensation value and the least squares method, including: Take either the I-channel local oscillator leakage compensation value or the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value; Obtain multiple preset values ​​for the target local oscillator leakage compensation value; For each preset value of the target local oscillator leakage compensation value, a feedback signal is collected on the feedback path, and the corresponding target feedback path energy is calculated based on the feedback signal; Based on each preset value of the target local oscillator leakage compensation value, the energy of each target feedback path, and the least squares method, the parameter values ​​of each first parameter are calculated. Take the other of the I-channel local oscillator leakage compensation value and the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value, and return to the step of obtaining multiple preset values ​​of the target local oscillator leakage compensation value to obtain the parameter values ​​of each second parameter; The parameter values ​​of each of the first parameters and each of the second parameters are used as the parameter values ​​of each energy model parameter in the energy model.

2. The method according to claim 1, characterized in that, The step of constructing a radio frequency signal model based on the transmitter architecture includes: Set the original I-channel signal and original Q-channel signal transmitted by the baseband module in the transmitter to 0; The compensation values ​​of the original I-channel signal and the original Q-channel signal are calculated using a digital DC compensation module to obtain the I-channel compensated digital signal and the Q-channel compensated digital signal. The I-channel compensated digital signal and the Q-channel compensated digital signal are converted into I-channel analog baseband signal and Q-channel analog baseband signal by a digital-to-analog converter; The I-channel analog baseband signal and the Q-channel analog baseband signal are input into the upconverter in the transmitter architecture. The I-channel analog baseband signal and the Q-channel analog baseband signal are orthogonally modulated and added according to the local oscillator signal of the upconverter to obtain the initial radio frequency signal. The initial radio frequency signal is amplified using a power amplifier to obtain a radio frequency signal model under mathematical conditions.

3. The method according to claim 1, characterized in that, The construction of the feedback path signal model based on the aforementioned radio frequency signal model and feedback path architecture includes: Obtain the local oscillator signal of the downconverter from the architecture of the feedback path; The radio frequency signal model is multiplied by the cosine and sinine components of the local oscillator signal to obtain the first initial baseband analog signal and the second initial baseband analog signal of the feedback path. Substituting the complete expression of the radio frequency signal model into the formulas of the first initial baseband analog signal and the second initial baseband analog signal, the high-frequency components of the signal in the frequency domain are filtered out by the low-pass filter in the feedback path architecture, and the gain of the transmit path and the gain of the feedback path are combined to construct the feedback path signal model.

4. A transmitter local oscillator leakage frequency shift self-calibration device, characterized in that, The device includes: A construction unit is used to construct an energy model based on the architecture of the transmitter and feedback path; the energy model characterizes the relationship between the local oscillator leakage compensation value and the energy of the feedback path. The estimation unit is used to estimate the parameter values ​​of each energy model parameter in the energy model based on the preset value of the local oscillator leakage compensation value and the least squares method. The calculation unit is used to calculate the optimal local oscillator leakage compensation value based on the energy model and the parameter values ​​of each of the energy model parameters; A self-calibration unit is used to perform reverse compensation for local oscillator leakage of the transmitter using the optimal local oscillator leakage compensation value; The building unit includes: The first building module is used to build a radio frequency signal model based on the transmitter architecture; The second building module is used to build a feedback path signal model based on the radio frequency signal model and the architecture of the feedback path; The first determining module is used to determine the feedback path energy calculation model based on the feedback path signal model and the preset energy calculation method; the feedback path energy calculation model contains unknown constants; The second determining module is used to determine the target value of the unknown constant based on the gain of the digital-to-analog converter in the transmitter; the target value of the unknown constant enables the feedback path energy calculated by the feedback path energy calculation model to reach the minimum value. The third construction module is used to construct an energy model based on the energy calculation model of the feedback path and the target value of the unknown constant; The local oscillator leakage compensation value includes: I-channel local oscillator leakage compensation value and Q-channel local oscillator leakage compensation value; The estimation unit includes: The first marking module is used to take either the I-channel local oscillator leakage compensation value or the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value. The acquisition module is used to acquire multiple preset values ​​of the target local oscillator leakage compensation value; The first calculation module is used to collect feedback signals on the feedback path for each preset value of the target local oscillator leakage compensation value, and calculate the corresponding target feedback path energy based on the feedback signals. The second calculation module is used to calculate the parameter values ​​of each first parameter based on each preset value of the target local oscillator leakage compensation value, the energy of each target feedback path, and the least squares method. The return module is used to take the other of the I-channel local oscillator leakage compensation value and the Q-channel local oscillator leakage compensation value as the target local oscillator leakage compensation value, and return to the execution of the acquisition module to obtain the parameter values ​​of each second parameter; The second marking module is used to take the parameter values ​​of each of the first parameters and the parameter values ​​of each of the second parameters as the parameter values ​​of each energy model parameter in the energy model.

5. The apparatus according to claim 4, characterized in that, The first building module includes: The configuration submodule is used to set the original I-channel signal and the original Q-channel signal transmitted by the baseband module in the transmitter to 0; The first calculation submodule is used to calculate the compensation values ​​of the original I-channel signal and the original Q-channel signal using the digital DC compensation module, so as to obtain the I-channel compensated digital signal and the Q-channel compensated digital signal. The conversion submodule is used to convert the I-channel compensated digital signal and the Q-channel compensated digital signal into an I-channel analog baseband signal and a Q-channel analog baseband signal through a digital-to-analog converter; The modulation submodule is used to input the I-channel analog baseband signal and the Q-channel analog baseband signal into the upconverter in the transmitter architecture, and to perform quadrature modulation on the I-channel analog baseband signal and the Q-channel analog baseband signal according to the local oscillator signal of the upconverter and add them together to obtain the initial radio frequency signal; The amplification submodule is used to amplify the initial radio frequency signal using a power amplifier to obtain a radio frequency signal model under mathematical mode.

6. The apparatus according to claim 4, characterized in that, The second building module includes: The acquisition submodule is used to acquire the local oscillator signal of the downconverter from the architecture of the feedback path; The second calculation submodule is used to multiply the radio frequency signal model by the cos component and sin component of the local oscillator signal respectively to obtain the first initial baseband analog signal and the second initial baseband analog signal of the feedback path; A submodule is constructed to substitute the complete expression of the radio frequency signal model into the formulas of the first initial baseband analog signal and the second initial baseband analog signal, filter out the high-frequency components of the signal in the frequency domain through the low-pass filter in the feedback path architecture, and combine the gain of the transmit path and the gain of the feedback path to construct the feedback path signal model.

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