Automatic calibration system and automatic calibration method of signal analyzer

Abstract

The invention provides an automatic calibration system and an automatic calibration method of a signal analyzer. The automatic calibration system at least comprises a signal generator, a first signal analyzer and a second signal analyzer to be calibrated, wherein the signal generator is used for generating a radio frequency signal with a preset digital characteristic; the first signal analyzer has a known frequency response characteristic; a first signal analyzer analyzes the radio frequency signal to obtain a first frequency response characteristic of the radio frequency signal, and a second analyzer receives the radio frequency signal and the first frequency response characteristic of the radio frequency signal. Other nonlinear errors caused by the frequency response characteristics of the signal analyzer to be calibrated and the signal transmission link are offset, and the calibration compensation amount of the second signal analyzer is obtained through calculation, so that the second signal analyzer can automatically calibrate the measurement result when measuring other signals to be measured.

Description

Technical Field

[0001] The present application relates to the technical field of signal analysis and processing, and in particular to an automatic calibration system and an automatic calibration method for a signal analyzer. Background Art

[0002] A signal analyzer is an instrument used to analyze electronic signals. It transforms and processes the input electrical signals to provide a detailed analysis of the signal characteristics, including the signal's frequency, amplitude, phase, spectral characteristics, and time domain characteristics.

[0003] The two major characteristics of a signal analyzer are narrowband measurement and broadband measurement. Among them, narrowband measurement pays special attention to the amplitude characteristics of the signal, requiring the signal analyzer to have a higher amplitude accuracy to meet the test requirements. The attenuation in the hardware link of the signal analyzer is not the same at different frequencies, so it is necessary to calibrate the signal analyzer by using a power meter as a reference at different frequencies. Broadband measurement not only has requirements for the amplitude characteristics of the signal analyzer, but also has high requirements for the phase characteristics of the signal analyzer. Similarly, the amplitude and phase characteristics of the signal analyzer in the broadband are different at different frequencies. The hardware itself can optimize the amplitude and phase, but it is only optimization and cannot eliminate the nonlinearity of the amplitude and phase. Therefore, calibration is also required to meet the test requirements. It can be seen that in order to ensure that the instrument accurately measures the signal within the broadband range, broadband calibration of the signal analyzer is particularly important.

[0004] In the prior art, broadband calibration of a signal analyzer is performed based on a known baseband signal generation module. The baseband signal generation module generates a known baseband signal and inputs it into a mixing module. The mixing module mixes the baseband signal to a corresponding frequency. Then, the receiving and analyzing module obtains data and calculates the calibration result. The calibration result is the characteristics of the signal analyzer plus the characteristics of the mixing module. However, when this scheme is used to perform broadband calibration on a signal analyzer, the frequency response characteristics of the mixing module are not completely linear, and the frequency response characteristics of the signal analyzer itself cannot be completely restored and offset. The frequency response characteristics of the signal analyzer itself bring errors to the measurement and analysis results of the signal analyzer. Summary of the invention

[0005] The present application provides an automatic calibration system and an automatic calibration method for a signal analyzer, which can solve the technical problem that in the process of performing broadband calibration of a signal analyzer in the prior art, errors in the calibration compensation results of the signal analyzer are caused by the inability to accurately restore and offset the frequency response characteristics of the signal transmission link and the signal analyzer itself.

[0006] In a first aspect, an embodiment of the present application provides an automatic calibration system for a signal analyzer, comprising: A signal generator, used for generating a radio frequency signal with preset digital characteristics; A first signal analyzer is a reference device, used to receive the radio frequency signal and analyze a first frequency response characteristic of the radio frequency signal; wherein the frequency response characteristic of the first signal analyzer is known; The second signal analyzer is a device to be calibrated, and is used to receive the radio frequency signal and the first frequency response characteristic of the radio frequency signal, and calculate the calibration compensation amount of the second signal analyzer based on the first frequency response characteristic of the radio frequency signal; when the second signal analyzer measures the signal to be measured, the measurement result is automatically calibrated according to the calibration compensation amount.

[0007] In some embodiments, the first frequency response characteristic of the radio frequency signal is related to at least a digital characteristic of the radio frequency signal, a frequency response characteristic of the signal generator, and a frequency response characteristic of the first signal analyzer; The second signal analyzer is further used to analyze the second frequency response characteristics of the radio frequency signal; the second frequency response characteristics of the radio frequency signal are at least related to the digital characteristics of the radio frequency signal, the frequency response characteristics of the signal generator and the frequency response characteristics of the second signal analyzer; When the second signal analyzer calculates the calibration compensation amount, the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the second frequency response characteristics of the radio frequency signal are offset by the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the first frequency response characteristics of the radio frequency signal.

[0008] In some embodiments, the automatic calibration system of the signal analyzer further comprises a mixing module; the mixing module is connected to the signal generator, and is used to receive the radio frequency signal, and perform up-conversion, amplification and attenuation processing on the radio frequency signal, and transmit the processing result to the first signal analyzer and the second signal analyzer; The first frequency response characteristic of the radio frequency signal is at least related to the digital characteristic of the radio frequency signal, the frequency response characteristic of the signal generator, the frequency response characteristic of the mixing module and the frequency response characteristic of the first signal analyzer; the second frequency response characteristic of the radio frequency signal is at least related to the digital characteristic of the radio frequency signal, the frequency response characteristic of the signal generator, the frequency response characteristic of the mixing module and the frequency response characteristic of the second signal analyzer; When the second signal analyzer calculates the calibration compensation amount, the digital characteristics of the RF signal, the frequency response characteristics of the signal generator, and the frequency response characteristics of the mixing module in the second frequency response characteristics of the RF signal are offset by the digital characteristics of the RF signal, the frequency response characteristics of the signal generator, and the frequency response characteristics of the mixing module in the first frequency response characteristics of the RF signal.

[0009] In some embodiments, the calculation expression of the calibration compensation amount of the second signal analyzer is: ; in, is the calibration compensation amount of the second signal analyzer, is the frequency response characteristic of the second signal analyzer; is a first frequency response characteristic of the radio frequency signal; is a second frequency response characteristic of the radio frequency signal; is the frequency response characteristic of the first signal analyzer.

[0010] In some embodiments, the mixing module includes at least a radio frequency source, a mixer, an amplifier, and an attenuator; The RF source is used to provide a local oscillator signal; the mixer is used to receive the RF signal and the local oscillator signal, and multiply and filter the RF signal and the local oscillator signal to output a high-frequency RF signal; the amplifier is used to amplify the high-frequency RF signal; and the attenuator is used to reduce reflection of the high-frequency RF signal.

[0011] In a second aspect, an embodiment of the present application further provides an automatic calibration method for a signal analyzer, comprising: Acquire a radio frequency signal with preset digital characteristics and a first frequency response characteristic of the radio frequency signal; wherein the first frequency response characteristic of the radio frequency signal is obtained by analyzing a first signal analyzer; the first signal analyzer is a reference device, whose frequency response characteristic is known and whose measurement accuracy is higher than that of the signal analyzer to be calibrated; Based on the first frequency response characteristic of the radio frequency signal, a calibration compensation amount of the signal analyzer to be calibrated is calculated; According to the calibration compensation amount, when the signal analyzer to be calibrated measures the signal to be measured, the measurement result is automatically calibrated.

[0012] In some embodiments, the step of calculating the calibration compensation amount of the signal analyzer to be calibrated based on the first frequency response characteristic of the radio frequency signal includes: Analyzing a second frequency response characteristic of the radio frequency signal; Comparing a first frequency response characteristic and a second frequency response characteristic of the radio frequency signal; A calibration compensation amount of the signal analyzer to be calibrated is obtained by calculation.

[0013] In some embodiments, the first frequency response characteristic of the radio frequency signal is at least related to a digital characteristic of the radio frequency signal, a frequency response characteristic of a signal generator that emits the radio frequency signal, and a frequency response characteristic of the first signal analyzer; The second frequency response characteristic of the radio frequency signal is at least related to the digital characteristic of the radio frequency signal, the frequency response characteristic of the signal generator and the frequency response characteristic of the signal analyzer to be calibrated; When calculating and obtaining the calibration compensation amount of the signal analyzer to be calibrated, the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the second frequency response characteristics of the radio frequency signal are offset by the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the first frequency response characteristics of the radio frequency signal; The calculation expression of the calibration compensation amount of the signal analyzer to be calibrated is: ; in, is the calibration compensation amount of the signal analyzer to be calibrated; is the frequency response characteristic of the signal analyzer to be calibrated; is a first frequency response characteristic of the radio frequency signal; is a second frequency response characteristic of the radio frequency signal; is the frequency response characteristic of the first signal analyzer.

[0014] In some embodiments, the automatic calibration method of the signal analyzer further includes: performing mixing processing on the radio frequency signal; the mixing processing at least includes up-conversion, amplification and attenuation processing.

[0015] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, on which a computer-executable program or instruction is stored. When the program or instruction is executed by a processor, the steps of the automatic calibration method of the signal analyzer as described in any of the above embodiments are implemented.

[0016] The automatic calibration system and automatic calibration method of the signal analyzer provided in the embodiment of the present application, the automatic calibration system at least includes a signal generator for generating a radio frequency signal with preset digital characteristics, a first signal analyzer with known frequency response characteristics, and a second signal analyzer to be calibrated; the first signal analyzer analyzes the radio frequency signal to obtain the first frequency response characteristics of the radio frequency signal, the second analyzer receives the radio frequency signal and the first frequency response characteristics of the radio frequency signal, and based on the first frequency response characteristics of the radio frequency signal, calculates and obtains the calibration compensation amount of the second signal analyzer, so that the second signal analyzer can automatically calibrate the measurement results when measuring other signals to be measured. The present application introduces a reference signal analyzer, and uses the frequency response characteristics analysis results of the reference signal analyzer on the same radio frequency signal to offset other nonlinear errors caused by the frequency response characteristics of the signal analyzer to be calibrated itself and the signal transmission link, so as to obtain a more accurate calibration compensation amount, realize the linear compensation calibration of the signal analyzer to be calibrated, and ensure the accuracy and reliability of the subsequent measurement results of the signal analyzer to be calibrated.

[0017] In addition, the present application also provides a computer-readable storage medium, a computer program product, and a chip, which have the same beneficial effects as the above-mentioned signal analyzer automatic calibration system and automatic calibration method. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0019] Figure 1 A schematic diagram of the structure of an automatic calibration system for a signal analyzer provided in one embodiment of the present application.

[0020] Figure 2 A schematic structural diagram of an automatic calibration system for a signal analyzer provided in another embodiment of the present application.

[0021] Figure 3 A flowchart of an automatic calibration method for a signal analyzer provided in one embodiment of the present application.

[0022] Figure 4 A flowchart for calculating a calibration compensation amount is provided for one embodiment of the present application.

[0023] Figure 5 A flowchart of an automatic calibration method for a signal analyzer provided in another embodiment of the present application.

[0024] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below by specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments adopt associated similar element numbers. In the following embodiments, many detailed descriptions are for making the present application better understood. However, those skilled in the art can easily recognize that some features can be omitted in different situations, or can be replaced by other elements, materials, methods. In some cases, some operations related to the present application are not shown or described in the specification, this is to avoid the core part of the present application being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations according to the description in the specification and the general technical knowledge in the art.

[0026] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various implementations. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a required sequence, unless otherwise specified that a certain sequence must be followed.

[0027] The terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable when appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are usually a class, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated before and after are in an "or" relationship. The "connection" and "connection" mentioned in this application, unless otherwise specified, include direct and indirect connections (connections).

[0028] In the prior art, when performing broadband calibration on a signal analyzer, the frequency range to be calibrated is first set on the signal analyzer, mainly by inputting the start frequency and the end frequency. At the same time, the number of scanning points is also set as needed to ensure that there are enough measurement points in the entire frequency range. After the signal analyzer to be calibrated receives the RF signal with known digital characteristics output by the signal generator, the signal processing module in the signal analyzer to be calibrated will analyze the frequency response characteristics of the received RF signal. The frequency response characteristics of RF signals usually involve multiple aspects, including the frequency response, phase response, group delay, etc. of the signal. The frequency response characteristics of RF signals have an important impact on equipment performance, communication quality, and human health. In the design and application of RF systems, full consideration of the optimization and adjustment of frequency response characteristics can ensure the stability and reliability of the system.

[0029] Frequency response characteristics of the RF signal received by the signal analyzer to be calibrated for: ; in, is the digital characteristic of the radio frequency signal; is the frequency response characteristic of the signal analyzer to be calibrated.

[0030] It can be obtained that the frequency response characteristics of the signal analyzer to be calibrated are: ; Therefore, the calibration quantity of the signal analyzer to be calibrated is: ; Calibration can offset the frequency response characteristics of the signal analyzer itself, that is, it can eliminate measurement deviations caused by instrument errors, temperature changes, cables, connectors and other factors, thereby improving measurement accuracy and making the measured values ​​have good consistency and repeatability, reducing measurement uncertainties caused by instrument errors or improper operation, thereby improving measurement reliability and stability.

[0031] However, since the frequency range of signal analysis of a signal analyzer, such as a spectrum analyzer, is much larger than the frequency of the signal generated by the signal generator, the signal analyzer needs to use a mixer to mix the RF signal generated by the signal generator before receiving the signal. However, the amplitude and phase response of the mixer itself are unknown. When the signal analyzer is calibrated using the above method, only the frequency response characteristics of the signal analyzer itself can be offset, and the frequency response characteristics brought by the mixer cannot be offset. The result obtained can be regarded as an optimized result, and it is not possible to achieve more accurate compensation for the nonlinear error caused by the signal processing process.

[0032] The present application proposes an automatic calibration system for a signal analyzer, which introduces a high-precision signal analyzer with known frequency response characteristics as a reference device in the existing system. The reference device and the device to be calibrated receive the same radio frequency signal, and the frequency response characteristics of the received radio frequency signal are analyzed and compared respectively to offset the nonlinear error in the signal processing process to determine the frequency response characteristics of the device to be calibrated, and then determine the compensation amount that needs to be calibrated, so that when the device to be calibrated performs signal measurement, the measurement result can be automatically calibrated.

[0033] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0034] Figure 1 This is a schematic diagram of the structure of an automatic calibration system for a signal analyzer provided by an embodiment of the present application. Figure 1 As shown, the automatic calibration system of a signal analyzer provided in this embodiment includes a signal generator 110 , a first signal analyzer 120 and a second signal analyzer 130 .

[0035] In this embodiment, the signal generator is used to generate a radio frequency signal with preset digital characteristics. By setting the output frequency of the signal generator according to the preset digital characteristics, the output amplitude of the signal generator is adjusted to match the amplitude requirements in the preset digital characteristics. If the preset digital characteristics include modulation requirements, such as amplitude modulation (AM), frequency modulation (FM), phase modulation (PM), etc., it is necessary to set the corresponding modulation parameters on the signal generator to obtain the radio frequency signal with preset digital characteristics. The digital characteristics of the radio frequency signal are mainly reflected in its modulation method, spread spectrum technology, and the characteristics and parameters of signal transmission. They not only improve the data transmission rate and capacity, but also enhance the anti-interference ability and confidentiality, optimize the signal transmission quality, and support a variety of communication protocols and standards.

[0036] In this embodiment, the first signal analyzer is a reference device, which is used to receive the radio frequency signal and analyze the first frequency response characteristics of the radio frequency signal; wherein the frequency response characteristics of the first signal analyzer are known. The second signal analyzer is a device to be calibrated, which is used to receive the radio frequency signal and the first frequency response characteristics of the radio frequency signal. Based on the first frequency response characteristics of the radio frequency signal, the calibration compensation amount of the second signal analyzer can be calculated. When the second signal analyzer is used to measure the signal to be measured, the measurement result is automatically calibrated according to the calibration compensation amount.

[0037] It can be understood that the frequency response characteristics of the RF signal to be analyzed by the signal analyzer are at least related to the frequency response characteristics of the signal generator and the signal analyzer receiving the signal. Therefore, if the frequency response characteristics of the signal generator and the signal analyzer receiving the signal are known, the frequency response characteristics of the RF signal to be analyzed by the signal analyzer are known. In this embodiment, the first signal analyzer is a high-precision signal analyzer with known frequency response characteristics. It is used as a reference device. After receiving the RF signal output by the signal generator, the first signal analyzer's own signal processing unit will analyze the received signal and obtain the frequency response characteristics of the RF signal. Similarly, as the device to be calibrated, the second signal analyzer's own signal processing unit will also analyze the received RF signal and obtain the frequency response characteristics of the RF signal.

[0038] In some embodiments, based on the signal processing principle of the signal analyzer and the characteristics of the RF signal, the first frequency response characteristics of the RF signal are at least related to the digital characteristics of the RF signal, the frequency response characteristics of the signal generator, and the frequency response characteristics of the first signal analyzer. The second frequency response characteristics of the RF signal are at least related to the digital characteristics of the RF signal, the frequency response characteristics of the signal generator, and the frequency response characteristics of the second signal analyzer.

[0039] That is to say, when the digital characteristics of the received RF signal, the frequency response characteristics of the signal generator that transmits the RF signal, and the frequency response characteristics of the signal analyzer itself are known, the frequency response characteristics of the received RF signal can be calculated.

[0040] That is, when the signal processing unit of the first signal analyzer calculates the frequency response characteristics of the radio frequency signal, it is calculated at least based on the digital characteristics of the radio frequency signal, the frequency response characteristics of the signal generator and the frequency response characteristics of the first signal analyzer.

[0041] It can be understood that the frequency response characteristic result obtained by the first signal analyzer is recorded as the first frequency response characteristic of the RF signal, so the first frequency response characteristic of the RF signal It can be expressed as: ; in, is the digital characteristic of the RF signal; is the frequency response characteristic of the signal generator; This is the frequency response characteristic of the first signal analyzer.

[0042] Similarly, when the signal processing unit of the second signal analyzer analyzes the frequency response characteristics of the RF signal, it is calculated based on at least the digital characteristics of the RF signal, the frequency response characteristics of the signal generator and the frequency response characteristics of the second signal analyzer.

[0043] The frequency response characteristic result obtained by the second signal analyzer is recorded as the second frequency response characteristic of the RF signal. It can be expressed as: ; in, is the frequency response characteristic of the second signal analyzer.

[0044] For the same RF signal, its frequency response characteristics should be uniquely determined, so the frequency response characteristics of the second signal analyzer can be determined by comparing the analysis results of the two signal analyzers. In this process, regardless of whether the RF signal generated by the signal generator is processed, the nonlinear errors introduced by the processing process are the same and will be offset in the comparison process. Therefore, the frequency response characteristics of the second signal analyzer finally determined are accurate, and the calibration compensation of the second signal analyzer is also accurate and effective. Therefore, when the second signal analyzer is used to measure the signal to be measured, the accuracy and reliability of its measurement results can be guaranteed.

[0045] The second signal analyzer can calculate and obtain the frequency response characteristics of the second signal analyzer based on the second frequency response characteristics of the received signal and the first frequency response characteristics of the received radio frequency signal.

[0046] That is, from the above formula, we can get: ; The frequency response characteristics of the second signal analyzer are obtained as follows: for: ; Furthermore, the compensation amount for calibrating the second signal analyzer can be obtained. for: .

[0047] According to the calibration compensation amount, the measurement result can be automatically calibrated when the second signal analyzer measures the signal to be measured. For a signal analyzer that can set the compensation amount, the calibration compensation amount can be accurately set to ensure the accuracy of the measurement and analysis results in subsequent use.

[0048] It should be noted that there are many methods for calculating and analyzing the frequency response of RF signals, which may also include performing Fourier transform on the input and output signals, converting them from the time domain to the frequency domain, calculating the cross-power spectral density of the input and output signals, and using the cross-power spectral density divided by the auto-power spectral density to calculate the frequency response function, etc. This embodiment only provides a calculation method based on the analysis of RF signal principles, which is mainly used to illustrate that by using the first signal analyzer as a reference device, according to the frequency response characteristics of the same RF signal analyzed by it, the frequency response characteristics of the second signal analyzer to be calibrated can be compensated.

[0049] In summary, the automatic calibration system of the signal analyzer provided in this embodiment at least includes a signal generator for generating a radio frequency signal with preset digital characteristics, a first signal analyzer with known frequency response characteristics, and a second signal analyzer to be calibrated; the first signal analyzer analyzes the radio frequency signal to obtain the first frequency response characteristics of the radio frequency signal, and the second analyzer receives the radio frequency signal and the first frequency response characteristics of the radio frequency signal, and calculates and obtains the calibration compensation amount of the second signal analyzer based on the first frequency response characteristics of the radio frequency signal, so as to realize that the second signal analyzer can automatically calibrate the measurement results when measuring other signals to be measured. That is to say, by introducing a reference signal analyzer, using the frequency response characteristics analysis results of the reference signal analyzer on the same radio frequency signal, and offsetting other nonlinear errors caused by the frequency response characteristics of the signal analyzer to be calibrated itself and the signal transmission link, a more accurate calibration compensation amount can be obtained, and the linear compensation calibration of the signal analyzer to be calibrated is realized, ensuring the accuracy and reliability of the subsequent measurement results of the signal analyzer to be calibrated.

[0050] Figure 2 This is a schematic diagram of the structure of an automatic calibration system for a signal analyzer provided in another embodiment of the present application. Figure 2As shown, the automatic calibration system of the signal analyzer provided in this embodiment further includes a mixing module 140 based on the above embodiment.

[0051] In this embodiment, the input end of the mixing module is connected to the output end of the signal generator, and the mixing module is used to receive the radio frequency signal, and up-convert, amplify and attenuate the radio frequency signal, and transmit the processing result to the first signal analyzer and the second signal analyzer to ensure that the frequency of the radio frequency signal received by the first signal analyzer and the second signal analyzer is within its working range.

[0052] Considering that the frequency range of the signal analyzer is usually very large, such as 7.5G, 26.5G or higher, while the maximum frequency that can be reached by the arbitrary waveform signal generator is usually lower, such as 1G or 2G. Of course, there are signal generators with a high frequency range, but such broadband signal generation instruments are usually very expensive, which is not conducive to cost control of commercial projects. Therefore, in order to ensure that the frequency of the RF signal received by the first signal analyzer and the second signal analyzer is within their working range, it is necessary to perform a series of processing such as up-conversion, amplification and attenuation on the RF signal generated by the signal generator.

[0053] In some embodiments, the mixing module 140 includes at least a radio frequency source 1401, a mixer 1402, an amplifier 1403 and an attenuator 1404. The radio frequency source is used to provide a local oscillator signal, the frequency of which is different from that of the radio frequency signal, and is used for subsequent mixing processing. The mixer is used to receive the radio frequency signal and the local oscillator signal, and multiply and filter the radio frequency signal and the local oscillator signal to output a higher frequency radio frequency signal, that is, the frequency of the radio frequency signal output by the mixer is higher than the frequency of the radio frequency signal and the local oscillator signal. The amplifier is used to amplify the high-frequency radio frequency signal. Since there are requirements for the amplitude of the signal during the signal calibration process, the signal will be attenuated after passing through the mixer, and there will be a certain amount of signal attenuation in the signal transmission line, so it is necessary to add an amplifier to amplify the signal to meet the signal-to-noise ratio requirements. The attenuator is used to reduce the reflection of high-frequency radio frequency signals and improve the standing wave performance of the environment.

[0054] After receiving the RF signal output by the mixing module, the first signal analyzer and the second signal analyzer will perform down-conversion, filtering, attenuation and amplification on the received signal by their own signal processing units to obtain intermediate frequency signals, which will be sampled by their own ADCs and output to the processor for further calculation and analysis of the frequency response characteristics of the RF signal.

[0055] The frequency response characteristics of the mixing module are: Based on the signal processing principle of the signal analyzer and the characteristics of the RF signal, the first frequency response characteristics of the RF signal obtained by the first signal analyzer are It can be expressed as: ; The second frequency response characteristics obtained by the second signal analyzer It can be expressed as: ; By comparison, the frequency response characteristics of the second signal analyzer are for: ; Furthermore, the compensation amount for calibrating the second signal analyzer can be obtained as: ; It can also be seen from the above calculation process that in the automatic calibration system of the signal analyzer provided in this embodiment, other nonlinear errors caused by signal processing or transmission on the signal receiving link have no effect on the calibration result of the signal analyzer to be calibrated, and accurate compensation calibration results can be obtained with the help of the first signal analyzer.

[0056] That is to say, for a signal generator that uses a high-cost high-frequency broadband signal source, the signal analyzer to be calibrated can be automatically calibrated by using a high-precision reference signal analyzer with known frequency response characteristics. For a signal generator that uses a common arbitrary waveform, the frequency range of the RF signal can be changed by signal processing with other mixers, amplifiers, and attenuators, and then the reference signal analyzer can be used to automatically calibrate the signal analyzer to be calibrated.

[0057] Figure 3 This is a flow chart of an automatic calibration method for a signal analyzer provided by an embodiment of the present application. Figure 3 As shown, the automatic calibration method of the signal analyzer provided in this embodiment is applied to the signal analyzer to be calibrated, and the signal analyzer to be calibrated has at least one processor, and the processor is used to execute the steps of the automatic calibration method of the signal analyzer. The automatic calibration method of the signal analyzer specifically includes the following steps: Step S310, obtaining a radio frequency signal with preset digital characteristics and a first frequency response characteristic of the radio frequency signal; wherein the first frequency response characteristic of the radio frequency signal is obtained by analyzing with a first signal analyzer; the first signal analyzer is a reference device, whose frequency response characteristic is known and whose measurement accuracy is higher than that of the signal analyzer to be calibrated.

[0058] Step S320: Based on the first frequency response characteristic of the radio frequency signal, a calibration compensation amount of the signal analyzer to be calibrated is calculated.

[0059] Step S330: According to the calibration compensation amount, when the signal analyzer to be calibrated measures the signal to be measured, the measurement result is automatically calibrated.

[0060] In this embodiment, the RF signal with preset digital characteristics can be generated by any signal generator, and the reference signal analyzer is a high-precision signal analyzer with known frequency response characteristics. With it as a reference device, after receiving the RF signal output by the signal generator, the reference signal analyzer's own signal processing unit will analyze the received signal to obtain the frequency response characteristics of the RF signal. Similarly, the signal processing unit of the signal analyzer to be calibrated will also analyze the received RF signal to obtain the frequency response characteristics of the RF signal. For the same RF signal, its frequency response characteristics should be uniquely determined, so by comparing the analysis results of the two signal analyzers, the other nonlinear errors caused by the frequency response characteristics of the signal analyzer to be calibrated can be offset, and the frequency response characteristics of the signal analyzer to be calibrated can be determined, and then the correct calibration compensation amount can be obtained. In this process, no matter whether the RF signal generated by the signal generator is processed or not, the nonlinear errors introduced by the processing process are the same and will be offset in the comparison process. Therefore, the frequency response characteristics of the signal analyzer to be calibrated are accurate and the calibration compensation of the signal analyzer to be calibrated is accurate and effective. Therefore, when the second signal analyzer is used to measure the signal to be measured, the accuracy and reliability of the measurement results can be guaranteed.

[0061] Figure 4 A flowchart for calculating the calibration compensation amount is provided in one embodiment of the present application. Figure 4 As shown, in this embodiment, step S320, based on the first frequency response characteristic of the radio frequency signal, calculates and obtains the calibration compensation amount of the signal analyzer to be calibrated, specifically including the following steps: Step S3201: Analyze the second frequency response characteristics of the radio frequency signal.

[0062] Step S3202: compare the first frequency response characteristic and the second frequency response characteristic of the radio frequency signal.

[0063] Step S3203: Calculate and obtain the calibration compensation amount of the signal analyzer to be calibrated.

[0064] It can be understood that, based on the signal processing principle of the signal analyzer and the characteristics of the RF signal, the first frequency response characteristic of the RF signal is at least related to the digital characteristics of the RF signal, the frequency response characteristics of the signal generator, and the frequency response characteristics of the first signal analyzer. The second frequency response characteristic of the RF signal is at least related to the digital characteristics of the RF signal, the frequency response characteristics of the signal generator, and the frequency response characteristics of the second signal analyzer.

[0065] That is, the first frequency response characteristic of the RF signal can be expressed as: ; in, is the first frequency response characteristic of the RF signal; is the digital characteristic of the RF signal; is the frequency response characteristic of the signal generator; is the frequency response characteristic of the reference signal analyzer.

[0066] The second frequency response characteristic of the RF signal can be expressed as: ; in, is the second frequency response characteristic of the radio frequency signal; is the frequency response characteristic of the signal analyzer to be calibrated.

[0067] When calculating the calibration compensation amount of the signal analyzer to be calibrated, the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the second frequency response characteristics of the radio frequency signal are offset by the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the first frequency response characteristics of the radio frequency signal.

[0068] In other words, the frequency response characteristics of the second signal analyzer It can be expressed as: ; Furthermore, the compensation amount for calibrating the second signal analyzer can be calculated: for: .

[0069] According to the calibration compensation amount, when the second signal analyzer measures the signal to be measured, the measurement result can be automatically calibrated.

[0070] Figure 5 This is a flow chart of an automatic calibration method for a signal analyzer provided in another embodiment of the present application. Figure 5 As shown, the automatic calibration method of the signal analyzer provided in this embodiment specifically includes the following steps: Step S510: Acquire a radio frequency signal with preset digital characteristics.

[0071] Step S520, performing mixing processing on the radio frequency signal; the mixing processing at least includes up-conversion, amplification and attenuation processing.

[0072] Step S530: Obtain a first frequency response characteristic of the radio frequency signal. The first frequency response characteristic of the radio frequency signal is obtained by analyzing a first signal analyzer; the first signal analyzer is a reference device, whose frequency response characteristic is known and whose measurement accuracy is higher than that of the signal analyzer to be calibrated.

[0073] Step S540: Based on the first frequency response characteristic of the radio frequency signal, a calibration compensation amount of the signal analyzer to be calibrated is calculated.

[0074] Step S550: When the signal analyzer to be calibrated measures the signal to be measured, the measurement result is automatically calibrated according to the calibration compensation amount.

[0075] That is, based on any of the above embodiments, this embodiment performs a series of mixing processes including up-conversion, amplification and attenuation on the RF signal before comparing and analyzing the first frequency response characteristics of the RF signal and the frequency response characteristics of the signal analyzer to be calibrated, and changes the frequency range of the RF signal to the operating frequency range of the signal analyzer to be calibrated. Then, based on the analysis of the first signal analyzer, the first frequency response characteristics are obtained, and the frequency response characteristics of the signal analyzer to be calibrated are obtained, and other nonlinear errors caused by the frequency response characteristics of the signal analyzer to be calibrated itself and the signal transmission link are offset, and finally a calibration compensation amount is obtained to achieve automatic calibration of the signal analyzer to be calibrated.

[0076] It should be noted that there are many methods for calculating the frequency response of RF signals, which may also include performing Fourier transform on the input and output signals, converting them from the time domain to the frequency domain, calculating the cross-power spectral density of the input and output signals, and using the cross-power spectral density divided by the auto-power spectral density to calculate the frequency response function, etc. This embodiment only provides a basic calculation method, which is mainly used to illustrate that by using the first signal analyzer as a reference device, the frequency response characteristic compensation of the second signal analysis to be calibrated can be achieved.

[0077] In summary, by introducing a reference signal analyzer and using the frequency response characteristics analysis results of the reference signal analyzer on the same RF signal, other nonlinear errors caused by the frequency response characteristics of the signal analyzer to be calibrated and the signal transmission link can be offset, so that a more accurate calibration compensation amount can be obtained, and the linear compensation calibration of the signal analyzer to be calibrated is realized. In addition, other nonlinear errors caused on the signal receiving link can be offset, and the calibration result has high accuracy, ensuring the accuracy and reliability of subsequent measurement results of the signal analyzer to be calibrated.

[0078] An embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the various processes of any embodiment of the automatic calibration method of the above-mentioned signal analyzer can be implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0079] The processor may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

[0080] An embodiment of the present application also provides a chip, which includes a processor and a communication interface, wherein the communication interface and the processor are coupled, and the processor is used to run programs or instructions to implement the various processes of any embodiment of the automatic calibration method of the above-mentioned signal analyzer, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0081] It can be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0082] An embodiment of the present application also provides a computer program product, which includes computer program code and is stored in a storage medium. When the computer program code runs on at least one processor, it can implement the various processes of any embodiment of the automatic calibration method of the above-mentioned signal analyzer and achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0083] Those skilled in the art will appreciate that all or part of the functions of the various methods in the above-mentioned embodiments can be implemented by hardware or by computer programs. When all or part of the functions in the above-mentioned embodiments are implemented by computer programs, the program can be stored in a computer-readable storage medium, and the storage medium can include: read-only memory, random access memory, disk, optical disk, hard disk, etc., and the program is executed by a computer to implement the above-mentioned functions. For example, the program is stored in the memory of the device, and when the program in the memory is executed by the processor, all or part of the above-mentioned functions can be implemented. In addition, when all or part of the functions in the above-mentioned embodiments are implemented by computer programs, the program can also be stored in a storage medium such as a server, another computer, disk, optical disk, flash disk or mobile hard disk, and can be downloaded or copied and saved in the memory of the local device, or the system of the local device is updated, and when the program in the memory is executed by the processor, all or part of the functions in the above-mentioned embodiments can be implemented.

[0084] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the inspiration of the present application, ordinary technicians in the field can make several simple deductions, deformations or substitutions based on the ideas of the present application without departing from the scope of protection of the purpose of the present application and the claims. All of these are within the protection of the present application.

Claims

1. An automatic calibration system for a signal analyzer, characterized in that: include: A signal generator, used for generating a radio frequency signal with preset digital characteristics; A first signal analyzer is a reference device, used to receive the radio frequency signal and analyze a first frequency response characteristic of the radio frequency signal; wherein the frequency response characteristic of the first signal analyzer is known; The second signal analyzer is a device to be calibrated, and is used to receive the radio frequency signal and the first frequency response characteristic of the radio frequency signal, and calculate the calibration compensation amount of the second signal analyzer based on the first frequency response characteristic of the radio frequency signal; when the second signal analyzer measures the signal to be measured, the measurement result is automatically calibrated according to the calibration compensation amount.

2. The automatic calibration system for a signal analyzer according to claim 1, characterized in that: The first frequency response characteristic of the radio frequency signal is at least related to the digital characteristic of the radio frequency signal, the frequency response characteristic of the signal generator and the frequency response characteristic of the first signal analyzer; The second signal analyzer is further used to analyze the second frequency response characteristics of the radio frequency signal; the second frequency response characteristics of the radio frequency signal are at least related to the digital characteristics of the radio frequency signal, the frequency response characteristics of the signal generator and the frequency response characteristics of the second signal analyzer; When the second signal analyzer calculates the calibration compensation amount, the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the second frequency response characteristics of the radio frequency signal are offset by the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the first frequency response characteristics of the radio frequency signal.

3. The automatic calibration system for a signal analyzer according to claim 2, characterized in that: It also includes a mixing module; the mixing module is connected to the signal generator, and is used to receive the radio frequency signal, and perform up-conversion, amplification and attenuation processing on the radio frequency signal, and transmit the processing results to the first signal analyzer and the second signal analyzer; The first frequency response characteristic of the radio frequency signal is at least related to the digital characteristic of the radio frequency signal, the frequency response characteristic of the signal generator, the frequency response characteristic of the mixing module and the frequency response characteristic of the first signal analyzer; the second frequency response characteristic of the radio frequency signal is at least related to the digital characteristic of the radio frequency signal, the frequency response characteristic of the signal generator, the frequency response characteristic of the mixing module and the frequency response characteristic of the second signal analyzer; When the second signal analyzer calculates the calibration compensation amount, the digital characteristics of the RF signal, the frequency response characteristics of the signal generator, and the frequency response characteristics of the mixing module in the second frequency response characteristics of the RF signal are offset by the digital characteristics of the RF signal, the frequency response characteristics of the signal generator, and the frequency response characteristics of the mixing module in the first frequency response characteristics of the RF signal.

4. The automatic calibration system for a signal analyzer according to any one of claims 1 to 3, characterized in that: The calculation expression of the calibration compensation amount of the second signal analyzer is: ; in, is the calibration compensation amount of the second signal analyzer, is the frequency response characteristic of the second signal analyzer; is a first frequency response characteristic of the radio frequency signal; is a second frequency response characteristic of the radio frequency signal; is the frequency response characteristic of the first signal analyzer.

5. The automatic calibration system for a signal analyzer according to claim 3, characterized in that: The mixing module at least includes a radio frequency source, a mixer, an amplifier and an attenuator; The RF source is used to provide a local oscillator signal; the mixer is used to receive the RF signal and the local oscillator signal, and multiply and filter the RF signal and the local oscillator signal to output a high-frequency RF signal; the amplifier is used to amplify the high-frequency RF signal; and the attenuator is used to reduce reflection of the high-frequency RF signal.

6. A method for automatic calibration of a signal analyzer, characterized in that: include: Acquire a radio frequency signal with preset digital characteristics and a first frequency response characteristic of the radio frequency signal; wherein the first frequency response characteristic of the radio frequency signal is obtained by analyzing a first signal analyzer; the first signal analyzer is a reference device, whose frequency response characteristic is known and whose measurement accuracy is higher than that of the signal analyzer to be calibrated; Based on the first frequency response characteristic of the radio frequency signal, a calibration compensation amount of the signal analyzer to be calibrated is calculated; According to the calibration compensation amount, when the signal analyzer to be calibrated measures the signal to be measured, the measurement result is automatically calibrated.

7. The automatic calibration method of a signal analyzer according to claim 6, characterized in that: The step of calculating a calibration compensation amount of the signal analyzer to be calibrated based on the first frequency response characteristic of the radio frequency signal comprises: Analyzing a second frequency response characteristic of the radio frequency signal; Comparing a first frequency response characteristic and a second frequency response characteristic of the radio frequency signal; A calibration compensation amount of the signal analyzer to be calibrated is obtained by calculation.

8. The automatic calibration method of a signal analyzer according to claim 7, characterized in that: The first frequency response characteristic of the radio frequency signal is at least related to the digital characteristic of the radio frequency signal, the frequency response characteristic of the signal generator that emits the radio frequency signal, and the frequency response characteristic of the first signal analyzer; The second frequency response characteristic of the radio frequency signal is at least related to the digital characteristic of the radio frequency signal, the frequency response characteristic of the signal generator and the frequency response characteristic of the signal analyzer to be calibrated; When calculating and obtaining the calibration compensation amount of the signal analyzer to be calibrated, the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the second frequency response characteristics of the radio frequency signal are offset by the digital characteristics of the radio frequency signal and the frequency response characteristics of the signal generator in the first frequency response characteristics of the radio frequency signal; The calculation expression of the calibration compensation amount of the signal analyzer to be calibrated is: ； in, is the calibration compensation amount of the signal analyzer to be calibrated; is the frequency response characteristic of the signal analyzer to be calibrated; is a first frequency response characteristic of the radio frequency signal; is a second frequency response characteristic of the radio frequency signal; is the frequency response characteristic of the first signal analyzer.

9. The automatic calibration method for a signal analyzer according to any one of claims 6 to 8, characterized in that: Also includes: Performing frequency mixing processing on the radio frequency signal; The mixing process at least includes up-conversion, amplification and attenuation processes.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer-executable program or instruction, and when the program or instruction is executed by a processor, the automatic calibration method of the signal analyzer according to any one of claims 6 to 9 is implemented.

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