Voltage frequency generation method for frequency modulation nonlinear compensation of voltage-controlled oscillator

Abstract

The invention discloses a voltage frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator, and the method comprises the steps: selecting voltage values from a linear voltage frequency table one by one at different working environment temperatures, so as to control the voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value; selecting a part of signals from each voltage-controlled signal source as voltage-controlled reference signals, and calculating a frequency value corresponding to each voltage value based on the voltage-controlled reference signals; performing nonlinear correction on the frequency value corresponding to each voltage value to form a nonlinear voltage frequency table corresponding to different working environment temperatures; according to the invention, possible nonlinear characteristics of the voltage-controlled oscillator at the current temperature can be compensated in advance, and the problems of frequency modulation nonlinearity, excessive sensitivity to temperature and the like of the voltage-controlled oscillator are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of voltage-controlled oscillator calibration, and specifically relates to a voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator. Background Art

[0002] In today's rapidly advancing technology, radar technology, as a key means of information perception and detection, plays an irreplaceable role in many fields. Among them, millimeter-wave radar has been extremely widely used in many scenarios such as automotive assisted driving and industrial detection due to its unique advantages such as high resolution and strong anti-interference ability. To balance performance, reduce system complexity and hardware costs, and facilitate backend signal processing, millimeter-wave radar often uses a sawtooth wave or triangular wave voltage signal to modulate a voltage-controlled oscillator (VCO) to generate an ultra-wideband transmit signal and a receive local oscillator signal.

[0003] In a millimeter-wave radar system, the linearity of the frequency modulation signal generated by the voltage-controlled oscillator, that is, the linear degree of the change of the frequency modulation signal frequency with time, is a very critical parameter. It has a significant impact on many important performance indicators of millimeter-wave radar, such as range measurement accuracy, range resolution, target detection ability, and imaging accuracy. The linear frequency modulation source based on direct modulation of the voltage-controlled oscillator adopts an open-loop structure. This structural design is simple and has a low cost, and can meet the basic requirements of some application scenarios to a certain extent. However, its limitations are also very obvious, that is, the frequency modulation linearity is extremely vulnerable to various factors.

[0004] The change in ambient temperature is one of the important factors affecting the frequency modulation linearity. When the ambient temperature changes, the physical properties of semiconductor materials, such as carrier mobility and bandgap width, will change accordingly, resulting in the oscillation frequency of the voltage-controlled oscillator drifting, and causing the change of the frequency modulation signal frequency with time to deviate from the ideal linear relationship. Moreover, the ambient temperature varies greatly in different working scenarios, and the large temperature fluctuations make it difficult to guarantee the frequency modulation linearity of the voltage-controlled oscillator.

[0005] The differences in device processes also restrict the frequency modulation linearity. Due to slight deviations in the production process, even for components of the same model, their electrical parameters may be different. For example, the capacitance value of a capacitor, the inductance value of an inductor, etc. may deviate from the designed value, and these parameter deviations will directly affect the oscillation characteristics of the voltage-controlled oscillator, and further deteriorate the linearity of the frequency modulation signal.

[0006] The interference of electrical parasitic parameters cannot be ignored either. Factors such as circuit wiring and component packaging will generate electrical parasitic parameters such as parasitic capacitance and parasitic inductance. These parameters will interact with the main circuit of the voltage-controlled oscillator, resulting in additional circuit effects. Moreover, these electrical parasitic parameters are usually difficult to accurately measure and control, increasing the complexity of circuit design and posing a great challenge to ensuring the frequency modulation linearity of the voltage-controlled oscillator.

[0007] In summary, the interaction of multiple factors such as environmental temperature, device process, and electrical parasitic parameters severely restricts the frequency modulation linearity of the voltage-controlled oscillator based on the open-loop structure, thereby affecting the performance and application effects of devices such as millimeter-wave radars. Therefore, how to effectively compensate for the phase nonlinearity of the voltage-controlled oscillator and improve the frequency modulation linearity has become an important issue that urgently needs to be solved in the current radar technology field.

[0008] In related technologies, the patent application document with the publication number CN119093878A mainly uses a non-linear fitting scheme to achieve non-linear compensation of frequency modulation signals. The algorithm is relatively complex and the real-time performance is not good. At the same time, the influence of temperature drift on the millimeter-wave frequency modulation linearity is not considered, and it is difficult to implement secondary subsequent compensation in the system, so it is limited in the application of low-cost millimeter-wave radars. In the patent application document with the publication number CN102340370A, a pre-distorted voltage is obtained by pre-distorting the input voltage, and an output signal with a corresponding oscillation frequency is generated according to the pre-distorted voltage to correct the non-linear characteristics of the voltage-controlled oscillator, so that the input voltage and the oscillation frequency of the output signal are linearly related; however, this scheme does not consider the time-varying nature of the voltage-controlled oscillator aging and the influence of temperature on the millimeter-wave frequency modulation linearity, and the complexity of frequency non-linear correction is relatively high, making it difficult to achieve the integrated generation and real-time correction of linear frequency modulation signals, so it is limited in the application of low-cost millimeter-wave radars. Summary of the Invention

[0009] The technical problem to be solved by the present invention is how to effectively compensate for the phase nonlinearity of the voltage-controlled oscillator and greatly improve the millimeter-wave frequency modulation linearity.

[0010] The present invention solves the above technical problems through the following technical means:

[0011] On the one hand, a voltage-frequency generation method for frequency modulation non-linear compensation of a voltage-controlled oscillator is proposed, including:

[0012] At different working environmental temperatures, voltage values are sequentially selected from a linear voltage-frequency table to control the voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value;

[0013] Part of the signals are respectively selected from each of the voltage-controlled signal sources as voltage-controlled reference signals, and the frequency values corresponding to each voltage value are calculated based on the voltage-controlled reference signals;

[0014] Nonlinearly correct the frequency values corresponding to each voltage value to form a nonlinear voltage-frequency table corresponding to different operating ambient temperatures.

[0015] Further, the step of successively selecting voltage values from the linear voltage-frequency table to control a voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value includes:

[0016] Successively select voltage values from the linear voltage-frequency table as digital voltage-controlled signals, and obtain an analog voltage signal by subjecting the digital voltage-controlled signals to a digital-to-analog converter;

[0017] After amplifying the analog voltage signal using an operational amplifier, filter out its high-frequency components using a low-pass filter to obtain an analog voltage-controlled signal;

[0018] Use the analog voltage-controlled signal to control a voltage-controlled oscillator to generate a corresponding voltage-controlled signal source.

[0019] Further, the construction process of the linear voltage-frequency table includes:

[0020] Determine the starting value, ending value, and depth of the linear voltage-frequency table according to the voltage-frequency relationship of the voltage-controlled oscillator, the gain of the operational amplifier, and the code value-voltage relationship of the digital-to-analog converter;

[0021] Based on the starting value, ending value, and depth of the linear voltage-frequency table, determine the voltage values stored in the linear voltage-frequency table.

[0022] Further, the step of respectively selecting partial signals from each of the voltage-controlled signal sources as voltage-controlled reference signals and calculating the frequency values corresponding to each voltage value based on the voltage-controlled reference signals includes:

[0023] Use a coupler to respectively couple partial signals from each of the voltage-controlled signal sources as the voltage-controlled reference signals;

[0024] Use a mixer to perform down-conversion processing on the voltage-controlled reference signals to obtain an analog intermediate-frequency signal;

[0025] Convert the analog intermediate-frequency signal to a digital intermediate-frequency signal through analog-to-digital conversion;

[0026] Perform frequency calculation on the digital intermediate-frequency signal to obtain the corresponding frequency value.

[0027] Further, the power of the voltage-controlled reference signal is within a range that enables the mixer to operate in a linear region.

[0028] Further, the step of using a mixer to perform down-conversion processing on the voltage-controlled reference signals to obtain an analog intermediate-frequency signal includes:

[0029] Perform analog down-conversion processing on the voltage-controlled reference signal to obtain a mixed-frequency signal;

[0030] Filter out the out-of-band spurious signals of the mixed-frequency signal to obtain a filtered mixed-frequency signal;

[0031] Perform power compensation amplification on the filtered mixed-frequency signal to obtain an amplified mixed-frequency signal;

[0032] Perform anti-aliasing filtering on the amplified mixed-frequency signal to obtain the analog intermediate-frequency signal.

[0033] Further, the performing frequency calculation on the digital intermediate-frequency signal to obtain a corresponding frequency value includes:

[0034] Perform discrete Fourier transform on the digital intermediate-frequency signal to obtain a frequency spectrum curve;

[0035] Perform peak search on the frequency spectrum curve to determine the peak of the frequency spectrum curve;

[0036] Perform frequency point fitting on the data at the peak of the frequency spectrum curve to obtain a corresponding frequency value.

[0037] Further, the performing frequency point fitting on the data at the peak of the frequency spectrum curve to obtain a corresponding frequency value includes:

[0038] Based on the data at the peak of the frequency spectrum curve, use a high-order polynomial interpolation algorithm to calculate the frequency value at the peak.

[0039] Further, the performing non-linear correction on the frequency values corresponding to each voltage value to form a non-linear voltage-frequency table corresponding to different working environment temperatures includes:

[0040] Construct a frequency vector group from the frequency values corresponding to each voltage value at each working environment temperature;

[0041] Traverse each element in the frequency vector group to find the index number of the element value closest to the linear frequency;

[0042] Take out the voltage value corresponding to this index number from the linear voltage-frequency table as the element value in the non-linear voltage-frequency table.

[0043] Further, the method further includes:

[0044] Regularly update the non-linear voltage-frequency table corresponding to different working environment temperatures.

[0045] In a second aspect, the present invention also proposes a voltage-frequency generation device for non-linear compensation of frequency modulation of a voltage-controlled oscillator, including:

[0046] A temperature control module for controlling the temperature of the working environment where the device is located;

[0047] A digital-to-analog conversion module, configured to sequentially select voltage values from a linear voltage-frequency table at different working ambient temperatures to control a voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value;

[0048] A coupler, configured to respectively select partial signals from each of the voltage-controlled signal sources as voltage-controlled reference signals;

[0049] A frequency calculation module, configured to calculate frequency values corresponding to each voltage value based on the voltage-controlled reference signals;

[0050] A frequency correction module, configured to perform non-linear correction on the frequency values corresponding to each voltage value to form a non-linear voltage-frequency table corresponding to different working ambient temperatures.

[0051] Further, the digital-to-analog conversion module includes:

[0052] A digital-to-analog converter, configured to perform digital-to-analog conversion on the voltage values sequentially selected from the linear voltage-frequency table as digital voltage-controlled signals to obtain analog voltage signals;

[0053] An operational amplifier, configured to amplify the analog voltage signals to obtain amplified analog voltage signals;

[0054] A low-pass filter, configured to filter out high-frequency components of the amplified analog voltage signals to obtain analog voltage-controlled signals.

[0055] Further, the frequency calculation module includes:

[0056] A down-conversion unit, configured to perform down-conversion processing on the voltage-controlled reference signals using a mixer to obtain analog intermediate-frequency signals;

[0057] An analog-to-digital conversion unit, configured to perform analog-to-digital conversion on the analog intermediate-frequency signals to obtain digital intermediate-frequency signals;

[0058] A frequency calculation unit, configured to perform frequency calculation on the digital intermediate-frequency signals to obtain corresponding frequency values.

[0059] Further, the down-conversion unit includes:

[0060] A mixer, configured to perform analog down-conversion processing on the voltage-controlled reference signals to obtain mixed signals;

[0061] A band-pass filter, configured to filter out out-of-band spurious signals of the mixed signals to obtain filtered mixed signals;

[0062] A compensation amplifier, configured to perform power compensation amplification on the filtered mixed signals to obtain amplified mixed signals;

[0063] An anti-aliasing filter is used to perform anti-aliasing filtering on the amplified mixed-frequency signal to obtain the analog intermediate-frequency signal.

[0064] Further, the frequency calculation unit includes:

[0065] A discrete Fourier transform sub-unit is used to perform a discrete Fourier transform on the digital intermediate-frequency signal to obtain a frequency spectrum curve;

[0066] A peak search sub-unit is used to search for peaks in the frequency spectrum curve to determine the peak of the frequency spectrum curve;

[0067] A frequency point fitting sub-unit is used to perform frequency point fitting on the data at the peak of the frequency spectrum curve to obtain the corresponding frequency value.

[0068] Further, the frequency correction module includes:

[0069] A frequency vector quantity construction unit is used to construct a frequency vector quantity from the frequency values corresponding to each voltage value at each working environment temperature;

[0070] A traversal search unit is used to traverse each element in the frequency vector group to find the index number of the element value closest to the linear frequency;

[0071] An element index unit is used to take out the voltage value corresponding to this index number from the linear voltage-frequency table as the element value in the non-linear voltage-frequency table.

[0072] In a third aspect, the present invention also proposes a compensation method for the frequency modulation non-linearity of a voltage-controlled oscillator, including:

[0073] When the system is in a normal working state, select the corresponding non-linear voltage-frequency table according to the current working environment temperature;

[0074] Generate a digital voltage control signal according to this non-linear voltage-frequency table to complete the frequency modulation non-linearity compensation of the voltage-controlled oscillator;

[0075] Among them, the non-linear voltage-frequency tables at different working environment temperatures are pre-generated by using the voltage-frequency generation method for the frequency modulation non-linearity compensation of the voltage-controlled oscillator as described above.

[0076] The advantages of the present invention are:

[0077] (1) The present invention comprehensively and accurately measures the frequency modulation of a voltage-controlled oscillator under various different working environmental temperatures. During the measurement process, the actual output of the frequency modulation signal is recorded in detail, and then a frequency modulation non-linear curve composed of the frequency values corresponding to the voltage values in the linear voltage-frequency table is obtained. These curves clearly reflect the non-linear characteristics of the frequency modulation of the voltage-controlled oscillator under different temperature conditions. Then, according to the characteristics of different non-linear curves, the frequency modulation signal is corrected specifically to generate a pre-distorted frequency modulation voltage-controlled signal, which can effectively eliminate or significantly reduce the non-linear components in the frequency modulation signal, can pre-compensate for the possible non-linear characteristics of the voltage-controlled oscillator at the current temperature, and solves the problems of non-linearity in the frequency modulation of the voltage-controlled oscillator and excessive sensitivity to temperature.

[0078] (2) The present invention conducts non-linear correction work in the digital domain and corrects the frequency modulation signal specifically. Digital domain processing has high flexibility and accuracy.

[0079] (3) The acquisition of the non-linear voltage-frequency table can be completed by a one-time calibration by an automatic test equipment when the device leaves the factory, and then stored in the system as a fixed coefficient file. When the system works, the corresponding non-linear voltage-frequency table is selected according to the current environmental temperature to complete the non-linear compensation of the frequency modulation of the voltage-controlled oscillator. There is no need to calculate the non-linear voltage-frequency table in real time every time the system works, which greatly reduces the computational resource overhead, can achieve millimeter-wave frequency modulation non-linear compensation with relatively low software and hardware costs, realizes the integrated generation and real-time correction of the linear frequency modulation signal of the millimeter-wave radar, and also has strong temperature robustness.

[0080] Additional aspects and advantages of the present invention will be given in part in the following description, will become apparent in part from the following description, or will be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] Figure 1 is a schematic flowchart of a voltage-frequency generation method for non-linear compensation of frequency modulation of a voltage-controlled oscillator proposed in an embodiment of the present invention;

[0082] Figure 2 is a schematic structural diagram of a voltage-frequency generation device for non-linear compensation of frequency modulation of a voltage-controlled oscillator proposed in an embodiment of the present invention;

[0083] Figure 3 is a schematic structural diagram of a digital-to-analog conversion module in an embodiment of the present invention;

[0084] Figure 4 is a schematic structural diagram of a down-conversion module in an embodiment of the present invention;

[0085] Figure 5 is a schematic structural diagram of a frequency calculation module in an embodiment of the present invention;

[0086] Figure 6 It is a schematic structural diagram of a voltage-controlled signal generation module in an embodiment of the present invention;

[0087] Figure 7 It is a schematic flowchart of a compensation method based on the frequency modulation nonlinearity of a voltage-controlled oscillator proposed in an embodiment of the present invention. Detailed implementation manners

[0088] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0089] As Figure 1 shown, a voltage-frequency generation method for compensating the frequency modulation nonlinearity of a voltage-controlled oscillator is proposed in the first embodiment of the present invention. The method includes the following steps:

[0090] S10. At different operating ambient temperatures, voltage values are sequentially selected from a linear voltage-frequency table to control a voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value;

[0091] Specifically, in this embodiment, when the system is in the factory calibration state, the temperature control module is used to accurately control the operating temperatures of the temperature-sensitive digital-to-analog conversion module and the voltage-controlled oscillator. In actual operation, a suitable temperature range needs to be reasonably selected according to the specific future operating environment of the device. For example, the ambient temperature range is set to -40°C to +86°C. When performing temperature scanning, the initially set ambient temperature can be set to the lowest ambient temperature, that is, -40°C, and the temperature scanning step is generally selected as +1°C or +2°C. Such a setting can not only comprehensively cover the possible operating temperature range but also ensure accurate testing and compensation of the performance of the voltage-controlled oscillator at different temperatures.

[0092] S20. Part of the signals are respectively selected from each of the voltage-controlled signal sources as voltage-controlled reference signals, and the frequency values corresponding to each voltage value are calculated based on the voltage-controlled reference signals;

[0093] In this embodiment, by comprehensively and accurately measuring the frequency modulation conditions of the voltage-controlled oscillator at various different operating ambient temperatures, during the measurement process, the actual output conditions of the frequency modulation signals are detailedly recorded, and then the frequency modulation nonlinear curves are obtained. These curves clearly reflect the nonlinear characteristics of the frequency modulation of the voltage-controlled oscillator, that is, the frequency values, under different temperature conditions.

[0094] S30. Nonlinearly correct the frequency values corresponding to each voltage value to form a nonlinear voltage-frequency table corresponding to different operating ambient temperatures.

[0095] By specifically correcting the frequency modulation signal according to different nonlinear curve characteristics to generate a pre-distorted voltage-controlled frequency modulation signal, the nonlinear components in the frequency modulation signal can be effectively eliminated or significantly reduced, and the possible nonlinear characteristics of the voltage-controlled oscillator at the current temperature can be pre-compensated, solving the problems of nonlinear frequency modulation of the voltage-controlled oscillator and excessive sensitivity to temperature.

[0096] As a further preferred technical solution, in the step S10, voltage values are sequentially selected from the linear voltage-frequency table to control the voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value, which specifically includes the following steps:

[0097] S11. Sequentially select a voltage value from the linear voltage-frequency table as the digital voltage-controlled signal a, and obtain an analog voltage signal by passing the digital voltage-controlled signal a through a digital-to-analog converter.

[0098] S12. After amplifying the analog voltage signal using an operational amplifier, filter out its high-frequency components using a low-pass filter to obtain a pure analog voltage-controlled signal b.

[0099] S13. Use the analog voltage-controlled signal b to control the voltage-controlled oscillator to generate a corresponding voltage-controlled signal source c.

[0100] It should be noted that the voltage values stored in the linear voltage-frequency table are distributed in an arithmetic progression. By scanning the linear voltage-frequency table, the actual output frequency of the voltage-controlled oscillator corresponding to each voltage value can be obtained.

[0101] As a further preferred technical solution, the construction process of the linear voltage-frequency table in the step S10 includes:

[0102] Determine the starting value, ending value, and depth of the linear voltage-frequency table according to the voltage-frequency relationship of the voltage-controlled oscillator, the gain of the operational amplifier, and the code value-voltage relationship of the digital-to-analog converter.

[0103] Based on the starting value, ending value, and depth of the linear voltage-frequency table, determine the voltage values stored in the linear voltage-frequency table.

[0104] Exemplarily, according to the voltage-frequency relationship of the voltage-controlled oscillator, the gain of the operational amplifier, and the code-voltage relationship of the digital-to-analog converter, this embodiment can accurately calculate the start and end values of the linear voltage-frequency table corresponding to the lowest and highest frequencies. Assuming that the output frequency range of the voltage-controlled oscillator is 19 GHz to 20 GHz, the corresponding control voltage range is 1 V to 4 V, the input range of the corresponding operational amplifier is 0.15 V to 4.65 V, and the start and end values of the linear voltage-frequency table are 1000 and 31000. Given that the maximum sweep period is 20 μs and the conversion rate of the digital-to-analog converter is 500 MSPS, it can be calculated that the depth of the table is 500×20 + 1 = 10001, that is, a total of 10001 voltage values need to be stored, denoted as: where are the voltage values stored in the linear voltage-frequency table.

[0105] As a further preferred technical solution, in step S20: select some signals from each of the voltage-controlled signal sources as voltage-controlled reference signals, and calculate the frequency values corresponding to each voltage value based on the voltage-controlled reference signals, which specifically includes the following steps:

[0106] S21. Use a coupler to couple some signals from each of the voltage-controlled signal sources c as the voltage-controlled reference signal d;

[0107] S22. Use a mixer to perform down-conversion processing on the voltage-controlled reference signal d to obtain an analog intermediate-frequency signal e;

[0108] S23. Convert the analog intermediate-frequency signal e through analog-to-digital conversion to obtain a digital intermediate-frequency signal f;

[0109] S24. Perform frequency calculation on the digital intermediate-frequency signal f to obtain the corresponding frequency value g.

[0110] It should be noted that in this embodiment, by coupling some signals from the voltage-controlled signal source c as the voltage-controlled reference signal, and jointly using methods such as down-conversion, discrete Fourier transform, and peak fitting to calculate the frequency values corresponding to the voltage values, the frequency estimation accuracy can be effectively improved.

[0111] As a further preferred technical solution, the power of the voltage-controlled reference signal d is in a range that enables the mixer to operate in the linear region

[0112] Exemplarily, the coupling degree of the coupler is preferably selected such that the power of the voltage-controlled reference signal d is about 10 dB lower than the 1 dB compression point of the mixer to ensure that the mixer operates in the linear region. The frequency range of the analog intermediate-frequency signal e is 1300 MHz to 2300 MHz, and the power range is -10 dBm to 0 dBm. The data rate of the analog-to-digital conversion is 2400 MSPS, and the effective number of data points for the discrete Fourier transform is 65536.

[0113] As a further preferred technical solution, in step S22: using a mixer to perform down-conversion processing on the voltage-controlled reference signal d to obtain an analog intermediate-frequency signal e, specifically including the following steps:

[0114] S221. Perform analog down-conversion processing on the voltage-controlled reference signal d to obtain a mixed-frequency signal;

[0115] S222. Filter out the out-of-band spurious signals of the mixed-frequency signal to obtain a filtered mixed-frequency signal;

[0116] S223. Perform power compensation and amplification on the filtered mixed-frequency signal to obtain an amplified mixed-frequency signal;

[0117] S224. Perform anti-aliasing filtering on the amplified mixed-frequency signal to obtain the analog intermediate-frequency signal e.

[0118] As a further preferred technical solution, in step S24: perform frequency calculation on the digital intermediate-frequency signal f to obtain a corresponding frequency value g, specifically including the following steps:

[0119] S241. Perform discrete Fourier transform on the digital intermediate-frequency signal f to obtain a frequency spectrum curve;

[0120] S242. Perform peak search on the frequency spectrum curve to determine the peak of the frequency spectrum curve;

[0121] S243. Perform frequency point fitting on the data at the peak of the frequency spectrum curve to obtain the corresponding frequency value g.

[0122] Further, based on the data samples near the peak curve in this embodiment, a high-order polynomial interpolation algorithm is used to calculate the frequency value g at the peak.

[0123] Exemplarily, in this embodiment, three amplitudes near the peak are selected, which are A0, A1, and A2 respectively, and the corresponding frequency values of these three points are f0, f1, and f2 respectively. Then the calculated frequency value g is:

[0124]

[0125] Where f is the frequency value g.

[0126] As a further preferred technical solution, in step S30: perform non-linear correction on the frequency values corresponding to each voltage value to form a non-linear voltage-frequency table corresponding to different operating ambient temperatures, which specifically includes the following steps:

[0127] S31. Form a frequency vector group from the frequency values corresponding to each voltage value at each operating ambient temperature;

[0128] S32. Traverse each element in the frequency vector group to find the index number of the element value closest to the linear frequency;

[0129] S33. Take out the voltage value corresponding to this index number from the linear voltage-frequency table as the element value in the non-linear voltage-frequency table.

[0130] It should be noted that in this embodiment, at a certain operating ambient temperature, voltage values are selected one by one from the linear voltage-frequency table, and the frequency values corresponding to all voltage values in the linear voltage-frequency table are calculated, so as to form a frequency vector group corresponding to each operating ambient temperature.

[0131] Exemplarily, when all voltage values in the linear voltage-frequency table are scanned, 10001 corresponding frequency values g will be obtained, denoted as When the voltage-controlled oscillator output is completely linear, the expected frequency vector composed of 10001 frequency values g is Unit: MHz. Starting from the first element in the frequency vector find the index number of the value closest to the linear frequency in and then take out the corresponding value in the vector based on this index number as the first element in the non-linear voltage-frequency table; similarly, then process the second, third elements... until all elements in the vector are processed, and a complete non-linear voltage-frequency table can be formed.

[0132] It should be understood that by performing non-linear correction on the frequency vector group corresponding to each operating ambient temperature, non-linear voltage-frequency tables at all temperature points can be obtained. For example, all to-be-set operating ambient temperatures are [-40, -38, -36,..., 84, 86], unit: °C. A total of 64 non-linear voltage-frequency tables related to temperature can be obtained. These non-linear voltage-frequency tables at different temperatures can comprehensively cover the frequency compensation requirements of the device under various operating ambient temperatures, ensuring effective compensation for the non-linearity of the voltage-controlled oscillator frequency modulation under any temperature condition.

[0133] In this embodiment, a non-linear voltage-frequency meter is formed in this way, which does not require complex digital calculations, has a fast correction speed, low computing resources, can directly map the control voltage value in reverse from the required frequency point value, and realizes the integrated generation and compensation of frequency modulation signals.

[0134] As a further preferred technical solution, the method further includes:

[0135] Periodically update the non-linear voltage-frequency meter corresponding to different working environment temperatures.

[0136] It should be noted that considering that after years of operation of the system, there may be phenomena such as aging of some components or drift of parameter values. At this time, factory calibration can be carried out again to complete the update of the non-linear voltage-frequency meter and ensure that the system always maintains high-precision frequency control performance.

[0137] In addition, as Figure 2 shown, the second embodiment of the present invention proposes a voltage-frequency generation device for frequency modulation non-linear compensation of a voltage-controlled oscillator. The device includes:

[0138] A temperature control module 201 for controlling the temperature of the working environment where the device is located;

[0139] A digital-to-analog conversion module 203 for selecting voltage values one by one from the linear voltage-frequency table output by the voltage-controlled signal generation module 202 at different working environment temperatures to control the voltage-controlled oscillator 204 to generate a voltage-controlled signal source corresponding to each voltage value;

[0140] A coupler 205 for respectively selecting partial signals from each of the voltage-controlled signal sources as voltage-controlled reference signals;

[0141] A frequency calculation module 206 for calculating the frequency values corresponding to each voltage value based on the voltage-controlled reference signals;

[0142] A voltage-controlled signal generation module 202 for non-linearly correcting the frequency values corresponding to each voltage value to form a non-linear voltage-frequency table corresponding to different working environment temperatures.

[0143] Among them, the connection relationship and functions between the modules are as follows:

[0144] The temperature control module 201: used to accurately control the environmental temperature of the compensation device to ensure that the device can work stably under different temperature conditions;

[0145] The voltage-controlled signal generation module 202 is connected to the digital-to-analog conversion module 203 and is used to output a digital voltage-controlled signal a to the digital-to-analog conversion module 203;

[0146] Digital-to-analog conversion module 203: Connected to the voltage-controlled oscillator 204, it is used to convert the digital voltage-controlled signal a into an analog voltage-controlled signal b and output the analog voltage-controlled signal b to the voltage-controlled oscillator module 204;

[0147] Voltage-controlled oscillator 204: Connected to the coupler 205, it is used to generate a voltage-controlled signal source c under the control of the analog voltage-controlled signal b and output the voltage-controlled signal source c to the coupler 205;

[0148] Coupler 205: Connected to the frequency multiplication and amplification module 207 and the down-conversion module 206, it is used to output the frequency multiplication excitation signal h and the voltage-controlled reference signal d to the frequency multiplication and amplification module 207 and the frequency calculation module 206 respectively;

[0149] Frequency multiplication and amplification module 207: It is used to multiply and amplify the frequency multiplication excitation signal h to generate the received local oscillator and the transmitted excitation signal required by the system;

[0150] Frequency calculation module 206: It is used to calculate the frequency value g corresponding to each voltage value based on the voltage-controlled reference signal d.

[0151] As a further preferred technical solution, the frequency calculation module 206 includes a down-conversion unit 206a, an analog-to-digital conversion unit 206b, and a frequency calculation unit 206c. The down-conversion unit 206a is connected to the analog-to-digital conversion unit 206b and is used to down-convert the voltage-controlled reference signal d into an analog intermediate-frequency signal e and output the analog intermediate-frequency signal e to the analog-to-digital conversion unit 206b; The analog-to-digital conversion unit 206b is connected to the frequency calculation unit 206c and is used to convert the analog intermediate-frequency signal e into a digital intermediate-frequency signal f and output the digital intermediate-frequency signal f to the frequency calculation unit 206c; The frequency calculation unit 206c is connected to the voltage-controlled signal generation module 202 and is used to calculate the frequency of the digital intermediate-frequency signal f to obtain the frequency value g and output the frequency value g to the voltage-controlled signal generation module 202.

[0152] It should be noted that in this embodiment, the down-conversion unit 206a, the analog-to-digital conversion unit 206b, and the frequency calculation unit 206c are only used in the calibration stage before the system leaves the factory. They can be used as general calibration devices and can be removed when the system is working normally, which greatly reduces the hardware cost of the system. This design concept not only improves the performance-price ratio of the device, but also simplifies the system structure and improves the reliability and stability of the system.

[0153] As a further preferred technical solution, as Figure 3 shown, the digital-to-analog conversion module 203 includes:

[0154] Digital-to-analog converter 203a, which is used to perform digital-to-analog conversion on the voltage values selected one by one from the linear voltage-frequency table as digital voltage-controlled signals to obtain analog voltage signals;

[0155] An operational amplifier 203b is used to amplify the analog voltage signal to obtain an amplified analog voltage signal;

[0156] A low-pass filter 203c is used to filter out the high-frequency components of the amplified analog voltage signal to obtain an analog voltage-controlled signal.

[0157] Specifically, as Figure 4 shown, the digital-to-analog conversion module 202 includes a digital-to-analog converter 203a, an operational amplifier 203b, and a low-pass filter 203c connected in sequence. The functions of each unit are as follows:

[0158] The digital-to-analog converter 203a is used to receive the digital voltage-controlled signal a from the voltage-controlled signal generation module 202, convert it into an analog voltage signal a1, and output it to the operational amplifier 203b; the operational amplifier 203b is used to amplify the analog voltage signal a1 to obtain an analog amplified signal a2, and output it to the low-pass filter 203c; the low-pass filter 203c is used to filter out the high-frequency components in the analog amplified signal a2 to obtain a pure analog voltage-controlled signal b, and output the analog voltage-controlled signal b to the voltage-controlled oscillator 204.

[0159] As a further preferred technical solution, as Figure 4 shown, the down-conversion unit 206a includes:

[0160] A mixer 206a1 is used to perform analog down-conversion processing on the voltage-controlled reference signal to obtain a mixed signal;

[0161] A band-pass filter 206a2 is used to filter out the out-of-band spurious signals of the mixed signal to obtain a filtered mixed signal;

[0162] A compensation amplifier 206a3 is used to perform power compensation amplification on the filtered mixed signal to obtain an amplified mixed signal;

[0163] An anti-aliasing filter 206a4 is used to perform anti-aliasing filtering on the amplified mixed signal to obtain the analog intermediate-frequency signal.

[0164] Specifically, the down-conversion unit 206a includes a mixer 206a1, a band-pass filter 206a2, a compensation amplifier 206a3, and an anti-aliasing filter 206a4 connected in sequence. The functions of each part are as follows:

[0165] The mixer unit 206a1 is used to receive the voltage-controlled reference signal d from the coupler 205, mix it with the local oscillation signal to obtain a mixed signal d1, and output it to the band-pass filter 206a2;

[0166] The band-pass filter 206a2 is used to filter out the out-of-band spurious signals in the mixed-frequency signal d1, obtain a band-pass filtered signal d2, and output it to the compensation amplifier 206a3;

[0167] The compensation amplifier 206a3 is used to perform power compensation amplification on the band-pass filtered signal d2, obtain an intermediate-frequency amplified signal d3, and output it to the anti-aliasing filter 206a4;

[0168] The anti-aliasing filter 206a4 is used to perform anti-aliasing filtering on the intermediate-frequency amplified signal d3, obtain an analog intermediate-frequency signal e, and output the analog intermediate-frequency signal e to the analog-to-digital conversion unit 206b.

[0169] As a further preferred technical solution, the frequency calculation unit 206c includes:

[0170] The discrete Fourier transform sub-unit 206c1 is used to perform a discrete Fourier transform on the digital intermediate-frequency signal to obtain a frequency spectrum curve;

[0171] The peak search sub-unit 206c2 is used to search for peaks in the frequency spectrum curve to determine the peak of the frequency spectrum curve;

[0172] The frequency point fitting sub-unit 206c3 is used to perform frequency point fitting on the data at the peak of the frequency spectrum curve to obtain the corresponding frequency value.

[0173] The frequency calculation unit 206c includes a discrete Fourier transform sub-unit 206c1, a peak search sub-unit 206c2, and a frequency point fitting sub-unit 206c3 that are connected in sequence. The functions of each part are as follows:

[0174] The discrete Fourier transform sub-unit 206c1 is used to receive the digital intermediate-frequency signal f from the analog-to-digital conversion module 207, perform a discrete Fourier transform on it to obtain intermediate-frequency spectrum data f1, and output it to the peak search sub-unit 206c2;

[0175] The peak search sub-unit 206c2 is used to search for peaks in the intermediate-frequency spectrum data f1 to determine the peak position in the frequency spectrum, obtain spectrum peak data f2, and output it to the frequency point fitting sub-unit 206c3;

[0176] The frequency point fitting sub-unit 206c3 is used to perform frequency point fitting on the spectrum peak data f2, calculate the accurate frequency value g, and output the frequency value g to the voltage-controlled signal generation module 202.

[0177] As a further preferred technical solution, the voltage-controlled signal generation module uses a non-linear correction unit to perform non-linear correction on the frequency values corresponding to each voltage value. The non-linear correction unit includes:

[0178] A frequency-to-group quantity construction subunit, configured to construct a frequency-to-group quantity from the frequency values corresponding to each voltage value at each operating ambient temperature;

[0179] A traversing search subunit, configured to traverse each element in the frequency vector group and search for the index number of the element value closest to the linear frequency;

[0180] An element index subunit, configured to take out the voltage value corresponding to the index number from the linear voltage-frequency table as the element value in the non-linear voltage-frequency table.

[0181] Specifically, as Figure 6 shown, the voltage-controlled signal generation module 202 includes: a waveform selection unit 202a, a linear voltage-frequency table 202b, a data selector 202c, a non-linear correction unit 202d, and a non-linear voltage-frequency table 202e. The data in the linear voltage-frequency table is used for initial calibration. After calibration is completed, the data in the non-linear voltage-frequency table is adopted, and the integrated generation and compensation of the frequency modulation signal are completed. The connection relationship and functions between each part are as follows:

[0182] The waveform selection unit 202a is connected to the data selector 202c, the linear voltage-frequency table 202b, and the non-linear voltage-frequency table 202e, and is configured to output a data source selection signal g1 to the data selector unit 202c to determine whether the data selector 202c obtains data from the linear voltage-frequency table or the non-linear voltage-frequency table; at the same time, it outputs frequency table index data g2 to the linear voltage-frequency table 202b and the non-linear voltage-frequency table 202e, for specifying the position to read data from the corresponding frequency table.

[0183] The linear voltage-frequency table 202b is connected to the data selector 202c, and is configured to output a linear table data source g3 to the data selector 202c, that is, the voltage value in the linear voltage-frequency table.

[0184] The data selector 202c: is connected to the digital-to-analog conversion module 203, and according to the data source selection signal g1 output by the waveform selection unit 202a, obtains data from the linear voltage-frequency table unit 202b or the non-linear voltage-frequency table unit 202e, and outputs a digital voltage-controlled signal a to the digital-to-analog conversion module 203.

[0185] The non-linear correction unit 202d is connected to the frequency calculation unit 206c and the non-linear voltage-frequency table 202e, and is configured to receive the frequency value g from the frequency calculation unit 206c, update the non-linear voltage-frequency table according to these frequency values, and output non-linear table update data g4 to the non-linear voltage-frequency table 202e.

[0186] The non-linear voltage frequency meter 202e is connected to the data selector 202c, and is used to output the non-linear table data source g5 to the data selector 202c, that is, the voltage frequency meter data after non-linear correction.

[0187] It should be noted that for other embodiments or specific implementation methods of the voltage frequency generation device for frequency modulation non-linear compensation of the voltage controlled oscillator of the present invention, reference may be made to the above method embodiments, and details are not described herein again.

[0188] In addition, as Figure 7 shown, the third embodiment of the present invention also proposes a compensation method based on the frequency modulation non-linearity of the voltage controlled oscillator. The method includes the following steps:

[0189] When the system is in the normal working state, select the corresponding non-linear voltage frequency meter according to the current working environment temperature;

[0190] Generate a digital voltage control signal according to the non-linear voltage frequency meter to complete the frequency modulation non-linear compensation of the voltage controlled oscillator;

[0191] Among them, the non-linear voltage frequency meters under different working environment temperatures are pre-generated by using the voltage frequency generation method for frequency modulation non-linear compensation of the voltage controlled oscillator as described in the first embodiment above.

[0192] Specifically, the implementation process of the compensation method based on the frequency modulation non-linearity of the voltage controlled oscillator in this embodiment is as follows:

[0193] S101. When the system is in the factory calibration state, use the temperature control device to set the working environment temperature.

[0194] S102. Select the voltage value from the linear voltage frequency meter as the digital voltage control signal a, convert the digital voltage control signal a through digital-to-analog conversion to obtain the analog voltage control signal b, and use the analog voltage control signal b to control the voltage controlled oscillator to generate the voltage control signal source c

[0195] S103. Couple a part of the signal from the voltage control signal source c as the voltage control reference signal d, down-convert the voltage control reference signal d to obtain the analog intermediate frequency signal e, convert the analog intermediate frequency signal e through analog-to-digital conversion to obtain the digital intermediate frequency signal f, and perform frequency calculation on the digital intermediate frequency signal f to obtain the frequency value g;

[0196] S104. Select the next voltage value from the linear voltage frequency meter, repeat steps S102 - S103 until the frequency values g corresponding to all voltage values are obtained, and perform non-linear correction on these frequency values g to form a non-linear voltage frequency meter;

[0197] S105. Set the next working environment temperature, repeat steps S102 - S104 until the non-linear voltage frequency meters at all temperature points are obtained.

[0198] S106. In the normal working state of the system, select the corresponding non-linear voltage-frequency table according to the current ambient temperature, and read out the data in the table one by one as the digital voltage-controlled signal a to complete the non-linear compensation of the frequency modulation of the voltage-controlled oscillator.

[0199] It should be noted that in practical applications, the acquisition of the non-linear voltage-frequency table in steps S101 - S105 can be completed by one-time calibration by an automatic test equipment when the device leaves the factory, and then stored in the system as a fixed coefficient file, without the need for real-time calculation every time the system works, greatly reducing the computational resource overhead. In this way, the compensation process for the non-linearity of the voltage-controlled oscillator frequency modulation is just a table reading operation, which is easy to implement on some low-cost processors such as single-chip microcontrollers.

[0200] When applying the embodiment of the present invention, a closed-loop measurement mechanism will be constructed, which can comprehensively and accurately measure the frequency modulation conditions of the voltage-controlled oscillator under various different ambient temperatures. During the measurement process, the actual output of the frequency modulation signal will be recorded in detail, and then the frequency modulation non-linear curve will be obtained. These curves clearly reflect the non-linear characteristics of the voltage-controlled oscillator frequency modulation under different temperature conditions.

[0201] Based on the obtained frequency modulation non-linear curve, the present invention will carry out non-linear correction work in the digital domain. Digital domain processing has high flexibility and accuracy, and can, according to the characteristics of different non-linear curves, use advanced algorithms and technologies to specifically correct the frequency modulation signal. In this way, the non-linear components in the frequency modulation signal can be effectively eliminated or significantly reduced.

[0202] After completing the non-linear correction, combined with the current ambient temperature situation, a pre-distorted frequency modulation voltage-controlled signal is generated. This pre-distorted signal is carefully designed and calculated, and it can pre-compensate for the possible non-linear characteristics of the voltage-controlled oscillator at the current temperature. When this pre-distorted frequency modulation voltage-controlled signal is input into the voltage-controlled oscillator, it can effectively offset its inherent non-linear factors, thereby achieving the non-linear compensation of the voltage-controlled oscillator.

[0203] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0204] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0205] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator, characterized in that Including: At different working ambient temperatures, voltage values are sequentially selected from a linear voltage-frequency table to control a voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value; Part of the signals are respectively selected from each of the voltage-controlled signal sources as voltage-controlled reference signals, and frequency values corresponding to each voltage value are calculated based on the voltage-controlled reference signals; Nonlinear correction is performed on the frequency values corresponding to each voltage value to form a nonlinear voltage-frequency table corresponding to different working ambient temperatures.

2. The voltage-frequency generation method for frequency modulation nonlinearity compensation of a voltage-controlled oscillator according to claim 1, wherein The step of sequentially selecting voltage values from a linear voltage-frequency table to control a voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value includes: Sequentially selecting voltage values from a linear voltage-frequency table as digital voltage-controlled signals, and obtaining an analog voltage signal by subjecting the digital voltage-controlled signals to a digital-to-analog converter; After amplifying the analog voltage signal using an operational amplifier, high-frequency components thereof are filtered out using a low-pass filter to obtain an analog voltage-controlled signal; The analog voltage-controlled signal is used to control a voltage-controlled oscillator to generate a corresponding voltage-controlled signal source.

3. The voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 2, wherein The construction process of the linear voltage-frequency table includes: Based on the voltage-frequency relationship of the voltage-controlled oscillator, the gain of the operational amplifier, and the code value-voltage relationship of the digital-to-analog converter, the starting value, the ending value, and the depth of the table of the linear voltage-frequency table are determined; Based on the starting value, the ending value, and the depth of the linear voltage-frequency table, the voltage values stored in the linear voltage-frequency table are determined.

4. The voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 1, wherein The step of respectively selecting part of the signals from each of the voltage-controlled signal sources as voltage-controlled reference signals and calculating frequency values corresponding to each voltage value based on the voltage-controlled reference signals includes: Using a coupler to couple part of the signals from each of the voltage-controlled signal sources as the voltage-controlled reference signals; Using a mixer to perform down-conversion processing on the voltage-controlled reference signals to obtain an analog intermediate-frequency signal; Subjecting the analog intermediate-frequency signal to analog-to-digital conversion to obtain a digital intermediate-frequency signal; Performing frequency calculation on the digital intermediate-frequency signal to obtain a corresponding frequency value.

5. The voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 4, characterized in that, The power of the voltage-controlled reference signal is within a range that enables the mixer to operate in a linear region.

6. The voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 4, characterized in that The step of using a mixer to perform down-conversion processing on the voltage-controlled reference signals to obtain an analog intermediate-frequency signal includes: Performing analog down-conversion processing on the voltage-controlled reference signals to obtain a mixed-frequency signal; Filtering out out-of-band spurious signals of the mixed-frequency signal to obtain a filtered mixed-frequency signal; Performing power compensation amplification on the filtered mixed-frequency signal to obtain an amplified mixed-frequency signal; Performing anti-aliasing filtering on the amplified mixed-frequency signal to obtain the analog intermediate-frequency signal.

7. The voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 4, characterized in that The step of performing frequency calculation on the digital intermediate-frequency signal to obtain a corresponding frequency value includes: Performing discrete Fourier transform on the digital intermediate-frequency signal to obtain a frequency spectrum curve; Performing peak search on the frequency spectrum curve to determine the peak of the frequency spectrum curve; Performing frequency point fitting on the data at the peak of the frequency spectrum curve to obtain a corresponding frequency value.

8. The voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 7, wherein The step of performing frequency point fitting on the data at the peak of the frequency spectrum curve to obtain a corresponding frequency value includes: Based on the data at the peak of the frequency spectrum curve, a high-order polynomial interpolation algorithm is used to calculate the frequency value at the peak.

9. The voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 1, wherein Non-linearly correcting the frequency values corresponding to each voltage value to form a non-linear voltage-frequency table corresponding to different operating environment temperatures, including: Forming a frequency vector by using the frequency values corresponding to each voltage value at each operating environment temperature; Traversing each element in the frequency vector group to find the index number of the element value closest to the linear frequency; Taking the voltage value corresponding to this index number from the linear voltage-frequency table as the element value in the non-linear voltage-frequency table.

10. The voltage-frequency generation method for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to any one of claims 1 to 9, characterized in that, The method further includes: Regularly updating the non-linear voltage-frequency table corresponding to different operating environment temperatures.

11. A voltage-frequency generating device for frequency modulation nonlinear compensation of a voltage-controlled oscillator, characterized in that Including: A temperature control module for controlling the temperature of the operating environment where the device is located; A digital-to-analog conversion module for, at different operating environment temperatures, sequentially selecting voltage values from the linear voltage-frequency table output by the voltage-controlled signal generation module to control a voltage-controlled oscillator to generate a voltage-controlled signal source corresponding to each voltage value; A coupler for respectively selecting partial signals from each of the voltage-controlled signal sources as voltage-controlled reference signals; A frequency calculation module for calculating the frequency values corresponding to each voltage value based on the voltage-controlled reference signals; A voltage-controlled signal generation module for non-linearly correcting the frequency values corresponding to each voltage value to form a non-linear voltage-frequency table corresponding to different operating environment temperatures.

12. The voltage-frequency generating device for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 11, wherein The digital-to-analog conversion module includes: A digital-to-analog converter for performing digital-to-analog conversion on the voltage values sequentially selected from the linear voltage-frequency table as digital voltage-controlled signals to obtain an analog voltage signal; An operational amplifier for amplifying the analog voltage signal to obtain an amplified analog voltage signal; A low-pass filter for filtering out high-frequency components of the amplified analog voltage signal to obtain an analog voltage-controlled signal.

13. The voltage-frequency generating device for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 11, wherein The frequency calculation module includes: A down-conversion unit for performing down-conversion processing on the voltage-controlled reference signal by using a mixer to obtain an analog intermediate-frequency signal; An analog-to-digital conversion unit for performing analog-to-digital conversion on the analog intermediate-frequency signal to obtain a digital intermediate-frequency signal; A frequency calculation unit for calculating the frequency of the digital intermediate-frequency signal to obtain the corresponding frequency value.

14. The voltage-frequency generating device for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 13, characterized in that, The down-conversion unit includes: A mixer for performing analog down-conversion processing on the voltage-controlled reference signal to obtain a mixed signal; A band-pass filter for filtering out out-of-band spurious signals of the mixed signal to obtain a filtered mixed signal; A compensation amplifier for performing power compensation amplification on the filtered mixed signal to obtain an amplified mixed signal; An anti-aliasing filter for performing anti-aliasing filtering on the amplified mixed signal to obtain the analog intermediate-frequency signal.

15. The voltage-frequency generating device for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 13, wherein The frequency calculation unit includes: A discrete Fourier transform sub-unit for performing discrete Fourier transform on the digital intermediate-frequency signal to obtain a frequency spectrum curve; A peak search sub-unit for performing peak search in the frequency spectrum curve to determine the peak of the frequency spectrum curve; A frequency point fitting sub-unit for performing frequency point fitting on the data at the peak of the frequency spectrum curve to obtain the corresponding frequency value.

16. The voltage-frequency generating device for frequency modulation nonlinear compensation of a voltage-controlled oscillator according to claim 11, characterized in that The voltage-controlled signal generation module uses a non-linear correction unit to non-linearly correct the frequency values corresponding to each voltage value. The non-linear correction unit includes: A frequency-to-group quantity construction subunit, configured to construct a frequency-to-group quantity from the frequency values corresponding to each voltage value at each operating ambient temperature; A traversal search subunit, configured to traverse each element in the frequency vector group and search for the index number of the element value closest to the linear frequency; An element index subunit, configured to take out the voltage value corresponding to the index number from the linear voltage-frequency table as the element value in the non-linear voltage-frequency table.

17. A compensation method based on the frequency modulation non-linearity of a voltage-controlled oscillator, characterized in that, Comprising: When the system is in a normal operating state, select a corresponding non-linear voltage-frequency table according to the current operating ambient temperature; Generate a digital voltage-controlled signal according to the non-linear voltage-frequency table to complete the non-linear compensation of the frequency modulation of the voltage-controlled oscillator; Wherein, the non-linear voltage-frequency tables at different operating ambient temperatures are pre-generated by using the voltage-frequency generation method for non-linear compensation of the frequency modulation of the voltage-controlled oscillator described in any one of claims 1 to 9.

Images