Automatic Calibration System and Automatic Calibration Method for Signal Analyzer

Abstract

The present application provides an automatic calibration system and an automatic calibration method for a signal analyzer. 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 characteristic of the radio frequency signal. The second analyzer receives the radio frequency signal and the first frequency response characteristic of the radio frequency signal, and based on the first frequency response characteristic of the radio frequency signal, cancels other non-linear errors caused by the frequency response characteristics of the signal analyzer to be calibrated itself and the signal transmission link, calculates and obtains the calibration compensation amount of the second signal analyzer, so as to enable the second signal analyzer to automatically calibrate the measurement result when measuring other signals to be measured.

Description

Technical Field

[0001] This application relates to the technical field of signal analysis and processing, and particularly relates 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. By transforming and processing the input electrical signals, it provides a detailed analysis of signal characteristics, including signal frequency, amplitude, phase, spectral characteristics, and time-domain characteristics, etc.

[0003] The two major characteristics of a signal analyzer are narrowband measurement and broadband measurement. Among them, narrowband measurement pays particular attention to the amplitude characteristics of the signal, and requires the signal analyzer to have a high amplitude accuracy to meet the test requirements. Since the attenuation in the hardware link of the signal analyzer is different at different frequencies, it is necessary to use a power meter as a reference to calibrate the signal analyzer at different frequencies. For broadband measurement, not only are there requirements for the amplitude characteristics of the signal analyzer, but also high requirements for the phase characteristics of the signal analyzer. Similarly, at different frequency points, the amplitude and phase characteristics of the signal analyzer in the broadband are different. Although the hardware itself can optimize the amplitude and phase, it is only optimization and cannot eliminate the non-linear situations of the amplitude and phase. Therefore, calibration is also required to meet the test requirements. It can be seen that in order to ensure accurate measurement of signals 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 based on a known baseband signal generation module. The known baseband signal generated by the baseband signal generation module is input into a mixing module, and the mixing module mixes the baseband signal to the corresponding frequency. Then, the receiving and analyzing module acquires 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 using this solution to perform broadband calibration on a signal analyzer, the frequency response characteristics of the mixing module are not completely linear and cannot completely restore and cancel the frequency response characteristics of the signal analyzer itself. 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] This 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 broadband calibration of a signal analyzer in the prior art, due to the inability to accurately restore and cancel the frequency response characteristics of the signal transmission link and the signal analyzer itself, the calibration compensation result of the signal analyzer has errors.

[0006] In a first aspect, an embodiment of this application provides an automatic calibration system for a signal analyzer, including:

[0007] A signal generator for generating a radio frequency signal with preset digital characteristics;

[0008] A first signal analyzer, as a reference device, for receiving the radio frequency signal and analyzing the first frequency response characteristic of the radio frequency signal; wherein, the frequency response characteristic of the first signal analyzer is known;

[0009] A second signal analyzer, as a device to be calibrated, for receiving the radio frequency signal and the first frequency response characteristic of the radio frequency signal, calculating a 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 a signal to be measured, automatically calibrating the measurement result according to the calibration compensation amount.

[0010] In some embodiments, the first frequency response characteristic of the radio frequency signal is at least related to the digital characteristics of the radio frequency signal, the frequency response characteristic of the signal generator, and the frequency response characteristic of the first signal analyzer;

[0011] The second signal analyzer is further configured to analyze a second frequency response characteristic of the radio frequency signal; the second frequency response characteristic of the radio frequency signal is at least related to the digital characteristics of the radio frequency signal, the frequency response characteristic of the signal generator, and the frequency response characteristic of the second signal analyzer;

[0012] When the second signal analyzer calculates the calibration compensation amount, the digital characteristics of the radio frequency signal and the frequency response characteristic of the signal generator in the second frequency response characteristic of the radio frequency signal cancel out the digital characteristics of the radio frequency signal and the frequency response characteristic of the signal generator in the first frequency response characteristic of the radio frequency signal.

[0013] In some embodiments, the automatic calibration system of the signal analyzer further includes a mixing module; the mixing module is connected to the signal generator for receiving the radio frequency signal, performing up-conversion, amplification, and attenuation processing on the radio frequency signal, and transmitting the processing result to the first signal analyzer and the second signal analyzer;

[0014] The first frequency response characteristic of the radio frequency signal is at least related to the digital characteristics 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 characteristics 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;

[0015] When the second signal analyzer calculates the calibration compensation amount, the digital characteristics of the radio frequency 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 radio frequency signal are cancelled out with the digital characteristics of the radio frequency 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 radio frequency signal.

[0016] In some embodiments, the calculation expression of the calibration compensation amount of the second signal analyzer is:

[0017] ;

[0018] Wherein, is the calibration compensation amount of the second signal analyzer, is the frequency response characteristic of the second signal analyzer; is the first frequency response characteristic of the radio frequency signal; is the second frequency response characteristic of the radio frequency signal; is the frequency response characteristic of the first signal analyzer.

[0019] In some embodiments, the mixing module includes at least a radio frequency source, a mixer, an amplifier, and an attenuator;

[0020] The radio frequency source is used to provide a local oscillator signal; the mixer is used to receive the radio frequency signal and the local oscillator signal, multiply and filter the radio frequency signal and the local oscillator signal, and output a high-frequency radio frequency signal; the amplifier is used to amplify the high-frequency radio frequency signal; the attenuator is used to reduce the reflection of the high-frequency radio frequency signal.

[0021] In a second aspect, an embodiment of the present application further provides an automatic calibration method for a signal analyzer, including:

[0022] Obtain a radio frequency signal with preset digital characteristics and the 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, its frequency response characteristic is known, and its measurement accuracy is higher than that of the signal analyzer to be calibrated;

[0023] Based on the first frequency response characteristic of the radio frequency signal, calculate the calibration compensation amount of the signal analyzer to be calibrated;

[0024] According to the calibration compensation amount, when the signal analyzer to be calibrated measures a signal to be measured, automatically calibrate the measurement result.

[0025] In some embodiments, the 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:

[0026] Analyze the second frequency response characteristic of the radio frequency signal;

[0027] Compare the first frequency response characteristic and the second frequency response characteristic of the radio frequency signal;

[0028] Calculate and obtain the calibration compensation amount of the signal analyzer to be calibrated.

[0029] In some embodiments, 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;

[0030] 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;

[0031] When calculating and obtaining the calibration compensation amount of the signal analyzer to be calibrated, the digital characteristic of the radio frequency signal and the frequency response characteristic of the signal generator in the second frequency response characteristic of the radio frequency signal are cancelled out with the digital characteristic of the radio frequency signal and the frequency response characteristic of the signal generator in the first frequency response characteristic of the radio frequency signal;

[0032] The calculation expression of the calibration compensation amount of the signal analyzer to be calibrated is:

[0033] ;

[0034] Wherein, 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 the first frequency response characteristic of the radio frequency signal; is the second frequency response characteristic of the radio frequency signal; is the frequency response characteristic of the first signal analyzer.

[0035] 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.

[0036] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, on which a program or instruction executed by a computer is stored, and 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.

[0037] The automatic calibration system and method for a signal analyzer provided by an 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 characteristic of the radio frequency signal. The second analyzer receives the radio frequency signal and the first frequency response characteristic of the radio frequency signal, and calculates and obtains the calibration compensation amount of the second signal analyzer based on the first frequency response characteristic of the radio frequency signal, so as to enable the second signal analyzer to automatically calibrate the measurement result when measuring other signals to be measured. By introducing a reference signal analyzer in the present application and using the analysis result of the frequency response characteristic of the same radio frequency signal by the reference signal analyzer, other non-linear errors caused by the frequency response characteristics of the signal analyzer to be calibrated itself and on the signal transmission link are offset, and a more accurate calibration compensation amount can be obtained, realizing linear compensation calibration for the signal analyzer to be calibrated, and ensuring the accuracy and reliability of the subsequent measurement results of the signal analyzer to be calibrated.

[0038] 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

[0039] The drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0040] Figure 1 It is a schematic structural diagram of an automatic calibration system for a signal analyzer provided by an embodiment of the present application.

[0041] Figure 2 It is a schematic structural diagram of an automatic calibration system for a signal analyzer provided by another embodiment of the present application.

[0042] Figure 3 It is a flowchart of an automatic calibration method for a signal analyzer provided by an embodiment of the present application.

[0043] Figure 4 It is a flowchart of calculating the calibration compensation amount provided by an embodiment of the present application.

[0044] Figure 5 It is a flowchart of an automatic calibration method for a signal analyzer provided by another embodiment of the present application.

[0045] Through the above-mentioned accompanying drawings, specific embodiments of the present application have been shown, and will be described in more detail hereinafter. These drawings and the written description are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by reference to specific embodiments. Detailed Description of the Embodiments

[0046] The present invention will be further described in detail below in conjunction with the accompanying drawings in specific embodiments. Similar elements in different embodiments are labeled with related similar element numbers. In the following embodiments, many details are described to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, and methods. In some cases, some operations related to the present application are not shown or described in the specification to avoid overwhelming the core part of the present application with excessive description. 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 based on the description in the specification and general technical knowledge in the art.

[0047] In addition, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can also be reordered or adjusted in an obvious manner by those skilled in the art. Therefore, the various sequences in the specification and drawings are only for clearly describing a certain embodiment and do not mean that they are necessary sequences, unless it is stated that a certain sequence must be followed.

[0048] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are usually of the same type and do not limit the number of objects. For example, the first object can be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means an "or" relationship between the related objects before and after. And the "connection" and "coupling" mentioned in the present application, unless otherwise specified, both include direct and indirect connection (coupling).

[0049] In the prior art, when performing broadband calibration on a signal analyzer, first, the frequency range to be calibrated is set on the signal analyzer, mainly the start frequency and end frequency of the input, and at the same time, the number of scan points is also set as needed to ensure that there are sufficient measurement points throughout the frequency range. After the signal analyzer to be calibrated receives the radio frequency 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 radio frequency signal. The frequency response characteristics of the radio frequency signal usually involve multiple aspects, including the frequency response, phase response, group delay, etc. The frequency response characteristics of the radio frequency signal have important impacts on aspects such as device performance, communication quality, and human health. In the design and application of radio frequency systems, fully considering the optimization and adjustment of the frequency response characteristics can ensure the stability and reliability of the system.

[0050] The frequency response characteristics of the radio frequency signal received by the signal analyzer to be calibrated are:

[0051] ;

[0052] wherein, is the digital characteristic of the radio frequency signal; is the frequency response characteristic of the signal analyzer to be calibrated.

[0053] It can be obtained that the frequency response characteristic of the signal analyzer to be calibrated is:

[0054] ;

[0055] Therefore, the calibration quantity of the signal analyzer to be calibrated is:

[0056] ;

[0057] By calibration, the frequency response characteristic of the signal analyzer itself is cancelled out, that is, the measurement deviation caused by factors such as instrument itself error, temperature change, cables and connectors can be eliminated, thereby improving the measurement accuracy, and also making the measurement values have good consistency and repeatability, reducing the measurement uncertainty caused by instrument error or improper operation, thereby improving the reliability and stability of the measurement.

[0058] However, since the frequency range of signal analysis by a signal analyzer, such as a spectrum analyzer, is much larger than the frequency of the generated signal of a signal generator, before the signal analyzer receives the signal, it is necessary to use a mixer to perform mixing processing on the radio frequency signal generated by the signal generator. However, the amplitude and phase responses of the mixer itself are unknown. When calibrating the signal analyzer using the above method, only the frequency response characteristics of the signal analyzer itself can be canceled, and the frequency response characteristics brought by the mixer cannot be canceled. The obtained result can be regarded as an optimized result, and it is impossible to accurately compensate for the nonlinear error caused by the signal processing process.

[0059] This application intends to propose an automatic calibration system for a signal analyzer. A high-precision signal analyzer with known frequency response characteristics is introduced as a reference device in the existing system. By receiving the same radio frequency signal with the reference device and the device to be calibrated, and analyzing and comparing the frequency response characteristics of the received radio frequency signals respectively, the nonlinear error in the signal processing process is canceled to determine the frequency response characteristics of the device to be calibrated, and then the compensation amount to be calibrated is determined, so as to automatically calibrate the measurement result when the device to be calibrated performs signal measurement.

[0060] The following uses specific embodiments to elaborate in detail on the technical solution of this application and how the technical solution of this application solves the above technical problems. These several 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 this application will be described below with reference to the accompanying drawings.

[0061] Figure 1 It is a schematic structural diagram of an automatic calibration system for a signal analyzer provided by an embodiment of this application. As Figure 1 shown, the automatic calibration system for a signal analyzer provided by this embodiment includes a signal generator 110, a first signal analyzer 120, and a second signal analyzer 130.

[0062] 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 and adjusting the output amplitude of the signal generator 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., corresponding modulation parameters need to be set on the signal generator to obtain a 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.

[0063] In this embodiment, the first signal analyzer is a reference device, which is used to receive a radio frequency signal and analyze the 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, which is used to receive the radio frequency signal and the first frequency response characteristic of the radio frequency signal. Based on the first frequency response characteristic of the radio frequency signal, the calibration compensation amount of the second signal analyzer can be calculated. When using the second signal analyzer to measure a signal to be measured, the measurement result is automatically calibrated according to the calibration compensation amount.

[0064] It can be understood that for the radio frequency signal to be analyzed by the signal analyzer, its frequency response characteristic is 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, then the frequency response characteristic of the radio frequency signal to be analyzed by the signal analyzer is known. In this embodiment, the first signal analyzer is a high-precision signal analyzer with a known frequency response characteristic. Taking it as a reference device, after the first signal analyzer receives the radio frequency signal output by the signal generator, its own signal processing unit will analyze the received signal, and the frequency response characteristic of the radio frequency signal can be obtained. Similarly, as a device to be calibrated, the second signal analyzer's own signal processing unit will also analyze the received radio frequency signal, and the frequency response characteristic of the radio frequency signal can be obtained.

[0065] In some embodiments, based on the principle of signal processing of the signal analyzer and the characteristics of the radio frequency signal, the first frequency response characteristic of the radio frequency signal is at least related to the digital characteristics 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 frequency response characteristic of the radio frequency signal is at least related to the digital characteristics of the radio frequency signal, the frequency response characteristic of the signal generator, and the frequency response characteristic of the second signal analyzer.

[0066] That is to say, when the digital characteristics of the radio frequency signal it receives, the frequency response characteristic of the signal generator transmitting the radio frequency signal, and the frequency response characteristic of the signal analyzer itself are known, the frequency response characteristic of the radio frequency signal it receives can be calculated.

[0067] That is, when the signal processing unit of the first signal analyzer calculates the frequency response characteristic of the radio frequency signal, it is at least calculated according to the digital characteristics of the radio frequency signal, the frequency response characteristic of the signal generator, and the frequency response characteristic of the first signal analyzer.

[0068] It can be understood that the frequency response characteristic result analyzed by the first signal analyzer is recorded as the first frequency response characteristic of the radio frequency signal. Therefore, the first frequency response characteristic of the radio frequency signal can be expressed as:

[0069] ;

[0070] wherein, are the digital characteristics of the radio frequency signal; are the frequency response characteristics of the signal generator; are the frequency response characteristics of the first signal analyzer.

[0071] Similarly, when the signal processing unit of the second signal analyzer analyzes the frequency response characteristics of the radio frequency signal, it is at least calculated 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 second signal analyzer.

[0072] Denote the result of the frequency response characteristics analyzed by the second signal analyzer as the second frequency response characteristic of the radio frequency signal. Therefore, the second frequency response characteristic of the radio frequency signal can be expressed as:

[0073] ;

[0074] wherein, are the frequency response characteristics of the second signal analyzer.

[0075] For the same radio frequency signal, its frequency response characteristics should be uniquely determined. Therefore, by comparing the analysis results of the two signal analyzers, the frequency response characteristics of the second signal analyzer can be determined. In this process, regardless of whether the radio frequency signal generated by the signal generator is signal processed, the non-linear errors introduced by the processing process are the same and will be cancelled out during the comparison. Therefore, the finally determined frequency response characteristics of the second signal analyzer are accurate, and the calibration compensation of the second signal analyzer is also accurate and effective. Therefore, when using the second signal analyzer to measure the signal to be measured, the accuracy and reliability of its measurement results can be guaranteed.

[0076] Based on the second frequency response characteristic of the received signal it analyzes and the first frequency response characteristic of the received radio frequency signal, the second signal analyzer can calculate the frequency response characteristics of the second signal analyzer.

[0077] That is, from the above formula, it can be obtained that

[0078] ;

[0079] It can be obtained that the frequency response characteristics of the second signal analyzer are:

[0080] ;

[0081] Furthermore, the compensation amount during the calibration of the second signal analyzer can be obtained as:

[0082] .

[0083] According to the above calibration compensation amount, when the second signal analyzer measures the signal to be measured, the measurement result can be automatically calibrated. 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 during subsequent use.

[0084] It should be noted that there are many methods for calculating and analyzing the frequency response of radio frequency signals. It may also include performing Fourier transforms 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 calculating the frequency response function by dividing the cross-power spectral density by the auto-power spectral density. This embodiment only provides a calculation method based on the principle analysis of radio frequency signals, mainly used to illustrate that by using the first signal analyzer as a reference device, according to the frequency response characteristics of the same radio frequency signal analyzed by it, the frequency response characteristics compensation of the second signal analyzer to be calibrated can be realized.

[0085] 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, the second analyzer receives the radio frequency signal and the first frequency response characteristics of the radio frequency signal, and calculates 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 when the second signal analyzer measures other signals to be measured, the measurement result can be automatically calibrated. That is to say, by introducing a reference signal analyzer and using the analysis result of the frequency response characteristics of the same radio frequency signal by the reference signal analyzer to offset other non-linear 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, realizing the linear compensation calibration of the signal analyzer to be calibrated, and ensuring the accuracy and reliability of the subsequent measurement results of the signal analyzer to be calibrated.

[0086] Figure 2 This is a schematic structural diagram of the automatic calibration system of the signal analyzer provided in another embodiment of the present application. As Figure 2 shown, on the basis of the above embodiment, the automatic calibration system of the signal analyzer provided in this embodiment further includes a mixing module 140.

[0087] In this embodiment, the input end of the mixing module is connected to the output end of the signal generator. The mixing module is used to receive the radio frequency signal, 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 to ensure that the frequencies of the radio frequency signals received by the first signal analyzer and the second signal analyzer are within their working ranges.

[0088] Considering that the frequency range of a signal analyzer is usually very large, such as 7.5G, 26.5G or higher, while for an arbitrary waveform signal generator, the maximum frequency it can reach is usually relatively low, such as 1G or 2G. Of course, there are also signal generators with a high frequency range, but such broadband signal generating instruments are usually very expensive, which is not conducive to cost control in commercial projects. Therefore, to ensure that the frequencies of the RF signals received by the first signal analyzer and the second signal analyzer are within their working ranges, a series of processes such as up-conversion, amplification, and attenuation processing need to be performed on the RF signals generated by the signal generator.

[0089] In some embodiments, the mixing module 140 includes at least an RF source 1401, a mixer 1402, an amplifier 1403, and an attenuator 1404. Among them, the RF source is used to provide a local oscillator signal, and the frequency of the local oscillator signal is different from that of the RF signal for subsequent mixing processing. The mixer is used to receive the RF signal and the local oscillator signal, multiply and filter the RF signal and the local oscillator signal, and output a higher-frequency RF signal. That is to say, the frequency of the RF signal output by the mixer is higher than the frequencies of the RF signal and the local oscillator signal. The amplifier is used to amplify this high-frequency RF signal. Since there are requirements for the amplitude of the signal during the signal calibration process, there will be signal attenuation after the signal passes through the mixer, and there is also a certain amount of signal attenuation in the signal transmission line. Therefore, an amplifier needs to be added to amplify the signal to meet the requirements of the signal-to-noise ratio. The attenuator is used to reduce the reflection of the high-frequency RF signal and improve the standing wave performance of the environment.

[0090] After the first signal analyzer and the second signal analyzer receive the RF signal output by the mixing module, their own signal processing units will perform processing such as down-conversion, filtering, attenuation, and amplification on the received signal to obtain an intermediate-frequency signal, and output it to the processor after ADC sampling by itself for further calculation and analysis of the frequency response characteristics of the RF signal.

[0091] Denote the frequency response characteristic of the mixing module as , and similarly based on the principle of signal analyzer signal processing and the characteristics of the RF signal, the first frequency response characteristic of the RF signal analyzed by the first signal analyzer can be expressed as:

[0092] ;

[0093] The second frequency response characteristic analyzed by the second signal analyzer can be expressed as:

[0094] ;

[0095] By comparison, the frequency response characteristic of the second signal analyzer is:

[0096] ;

[0097] Furthermore, the compensation amount during the calibration of the second signal analyzer can be obtained as follows:

[0098] ;

[0099] It can also be seen from the above calculation process that for the automatic calibration system of the signal analyzer provided in this embodiment, other non-linear errors caused by signal processing or transmission on the signal reception link have no influence on the calibration result of the signal analyzer to be calibrated. Only by relying on the first signal analyzer can an accurate compensation calibration result be obtained.

[0100] That is to say, for a signal generator that uses a high-cost high-frequency broadband signal source, through a high-precision reference signal analyzer with a known frequency response characteristic, the automatic calibration of the signal analyzer to be calibrated can be achieved. For a signal generator with a common arbitrary waveform, after changing the frequency range of the RF signal through signal processing by other mixers, amplifiers, and attenuators, the automatic calibration of the signal analyzer to be calibrated can also be achieved through the reference signal analyzer.

[0101] Figure 3 This is a flowchart of an automatic calibration method for a signal analyzer provided in an embodiment of the present application. As Figure 3 shown, the automatic calibration method for the signal analyzer provided in this embodiment is applied to the signal analyzer to be calibrated. 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 for the signal analyzer. The automatic calibration method for the signal analyzer specifically includes the following steps:

[0102] Step S310: Obtain an RF signal with a preset digital characteristic and the first frequency response characteristic of the RF signal; wherein, the first frequency response characteristic of the RF signal is obtained through analysis by a first signal analyzer; the first signal analyzer is a reference device, its frequency response characteristic is known, and its measurement accuracy is higher than that of the signal analyzer to be calibrated.

[0103] Step S320: Calculate the calibration compensation amount of the signal analyzer to be calibrated based on the first frequency response characteristic of the RF signal.

[0104] Step S330: According to the calibration compensation amount, when the signal analyzer to be calibrated measures the signal to be measured, automatically calibrate the measurement result.

[0105] In this embodiment, the radio frequency signal with preset digital characteristics can be generated by any signal generator. The reference signal analyzer is a high-precision signal analyzer with a known frequency response characteristic, which is used as a reference device. After receiving the radio frequency signal output by the signal generator, the signal processing unit of the reference signal analyzer will analyze the received signal to obtain the frequency response characteristic of the radio frequency signal. Similarly, the signal processing unit of the signal analyzer to be calibrated will also analyze the received radio frequency signal to obtain the frequency response characteristic of the radio frequency signal. For the same radio frequency signal, its frequency response characteristic should be uniquely determined. Therefore, by comparing the analysis results of the two signal analyzers, other non-linear errors caused by the frequency response characteristic of the signal analyzer to be calibrated itself can be cancelled, and the frequency response characteristic of the signal analyzer to be calibrated can be determined, and then the accurate calibration compensation amount can be obtained. In this process, regardless of whether signal processing is performed on the radio frequency signal generated by the signal generator, the non-linear errors introduced in the processing process are the same and will be cancelled in the comparison process. Therefore, the finally determined frequency response characteristic of the signal analyzer to be calibrated is accurate, and the calibration compensation of the signal analyzer to be calibrated is also accurate and effective. Therefore, when using the second signal analyzer to measure the signal to be measured, the accuracy and reliability of its measurement results can be guaranteed.

[0106] Figure 4 This is a flowchart for calculating the calibration compensation amount provided by an embodiment of the present application. As Figure 4 shown, in this embodiment, step S320, based on the first frequency response characteristic of the radio frequency signal, calculate the calibration compensation amount of the signal analyzer to be calibrated, which specifically includes the following steps:

[0107] Step S3201, analyze the second frequency response characteristic of the radio frequency signal.

[0108] Step S3202, compare the first frequency response characteristic and the second frequency response characteristic of the radio frequency signal.

[0109] Step S3203, calculate the calibration compensation amount of the signal analyzer to be calibrated.

[0110] It can be understood that based on the principle of signal processing of the signal analyzer and the characteristics of the radio frequency signal, the first frequency response characteristic of the radio frequency signal is at least related to the digital characteristics 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 frequency response characteristic of the radio frequency signal is at least related to the digital characteristics of the radio frequency signal, the frequency response characteristic of the signal generator, and the frequency response characteristic of the second signal analyzer.

[0111] That is, the first frequency response characteristic of the radio frequency signal can be expressed as:

[0112] ;

[0113] Where is the first frequency response characteristic of the radio frequency signal; is the digital characteristic of the radio frequency signal; is the frequency response characteristic of the signal generator; is the frequency response characteristic of the reference signal analyzer.

[0114] The second frequency response characteristic of the radio frequency signal can be expressed as:

[0115] ;

[0116] wherein, is the second frequency response characteristic of the radio frequency signal; is the frequency response characteristic of the signal analyzer to be calibrated.

[0117] When calculating the calibration compensation amount of the signal analyzer to be calibrated, the digital characteristic of the radio frequency signal and the frequency response characteristic of the signal generator in the second frequency response characteristic of the radio frequency signal are cancelled out with the digital characteristic of the radio frequency signal and the frequency response characteristic of the signal generator in the first frequency response characteristic of the radio frequency signal.

[0118] That is to say, the frequency response characteristic of the second signal analyzer can be expressed as:

[0119] ;

[0120] Furthermore, the compensation amount when calibrating the second signal analyzer can be calculated as :

[0121] .

[0122] According to the above calibration compensation amount, when the second signal analyzer measures the signal to be measured, the measurement result can be automatically calibrated.

[0123] Figure 5 is the flowchart of the automatic calibration method of the signal analyzer provided by another embodiment of the present application. As Figure 5 shown, the automatic calibration method of the signal analyzer provided by this embodiment specifically includes the following steps:

[0124] Step S510, obtain a radio frequency signal with a preset digital characteristic.

[0125] Step S520, perform mixing processing on the radio frequency signal; the mixing processing includes at least up-conversion, amplification and attenuation processing.

[0126] Step S530: Obtain the first frequency response characteristic of the RF signal. Among them, the first frequency response characteristic of the RF signal is obtained through analysis by the first signal analyzer; the first signal analyzer is a reference device, whose frequency response characteristic is known and the measurement accuracy is higher than that of the signal analyzer to be calibrated.

[0127] Step S540: Calculate the calibration compensation amount of the signal analyzer to be calibrated based on the first frequency response characteristic of the RF signal.

[0128] Step S550: Automatically calibrate the measurement result when the signal analyzer to be calibrated measures the signal to be measured according to the calibration compensation amount.

[0129] That is, on the basis of any of the above embodiments, before comparing and analyzing the first frequency response characteristic of the RF signal and the frequency response characteristic of the signal analyzer to be calibrated, a series of mixing processes including up-conversion, amplification, and attenuation are first performed on the RF signal to change the frequency range of the RF signal to the working frequency range of the signal analyzer to be calibrated, and then the first frequency response characteristic is obtained through analysis by the first signal analyzer, the frequency response characteristic of the signal analyzer to be calibrated is obtained, other non-linear errors caused by the frequency response characteristics of the signal analyzer to be calibrated itself and on the signal transmission link are offset, and finally the calibration compensation amount is obtained to realize the automatic calibration of the signal analyzer to be calibrated.

[0130] It should be noted that there are many methods for calculating the frequency response of the RF signal, which may also include performing Fourier transforms 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, mainly for explaining that by using the first signal analyzer as a reference device, the frequency response characteristic compensation of the second signal analyzer to be calibrated can be realized.

[0131] In summary, by introducing a reference signal analyzer and using the analysis result of the frequency response characteristic of the same RF signal by the reference signal analyzer to offset other non-linear errors caused by the frequency response characteristics of the signal analyzer to be calibrated itself and on the signal transmission link, a more accurate calibration compensation amount can be obtained, realizing the linear compensation calibration of the signal analyzer to be calibrated, and other non-linear errors caused on the signal reception link are offset, and the calibration result has high accuracy, ensuring the accuracy and reliability of the subsequent measurement results of the signal analyzer to be calibrated.

[0132] The 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, it can implement each process of any embodiment of the above automatic calibration method of the signal analyzer and can achieve the same technical effect. To avoid repetition, it will not be elaborated here.

[0133] Among them, the processor can be a Central Processing Unit (CPU for short), or an Application Specific Integrated Circuit (ASIC for short), or one or more integrated circuits configured to implement the embodiments of the present application. The readable storage medium includes computer-readable storage media such as computer read-only memory ROM, random access memory RAM, magnetic disks or optical discs, etc.

[0134] The embodiments of the present application further provide a chip, which includes a processor and a communication interface. Among them, the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of any embodiment of the above-mentioned automatic calibration method of the signal analyzer, and can achieve the same technical effects. To avoid repetition, it will not be elaborated here.

[0135] It can be understood that the chip mentioned in the embodiments of the present application can also be referred to as a system-on-chip, system chip, chip system, or system-on-chip, etc.

[0136] The embodiments of the present application further provide a computer program product, which includes computer program code 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 above-mentioned automatic calibration method of the signal analyzer, and can achieve the same technical effects. To avoid repetition, it will not be elaborated here.

[0137] Those skilled in the art can understand that all or part of the functions of the above-mentioned methods can be implemented in a hardware manner or in a computer program manner. When all or part of the functions in the above-mentioned embodiments are implemented in a computer program manner, the program can be stored in a computer-readable storage medium. The storage medium can include: read-only memory, random access memory, magnetic disks, optical discs, hard disks, etc. The above functions are implemented by a computer executing the program. For example, the program is stored in the memory of the device, and when the processor executes the program in the memory, the above-mentioned all or part of the functions can be implemented. In addition, when all or part of the functions in the above-mentioned embodiments are implemented in a computer program manner, the program can also be stored in storage media such as servers, other computers, magnetic disks, optical discs, flash drives, or external hard drives, and saved to the memory of the local device by downloading or copying, or the system of the local device is updated. When the processor executes the program in the memory, the above-mentioned all or part of the functions in the embodiments can be implemented.

[0138] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Those of ordinary skill in the art, under the inspiration of the present application, without departing from the purpose of the present application and the scope protected by the claims, for those skilled in the technical field to which the present invention pertains, based on the idea of the present invention, can also make several simple deductions, deformations or substitutions, all of which fall within the protection scope 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; 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.

2. The automatic calibration system for a signal analyzer according to claim 1, 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.

3. The automatic calibration system for a signal analyzer according to claim 1 or 2, 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.

4. The automatic calibration system for a signal analyzer according to claim 2, 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.

5. 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, automatically calibrating the measurement result; 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 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.

6. The automatic calibration method of a signal analyzer according to claim 5, 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.

7. The automatic calibration method of a signal analyzer according to claim 6, characterized in that: 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.

8. The automatic calibration method for a signal analyzer according to any one of claims 5 to 7, 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.

9. 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 5 to 8 is implemented.

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