Multi-domain synchronous real-time analysis and display method for complex signals in digital oscilloscope

Abstract

The invention discloses a multi-domain synchronous real-time analysis and display method for complex signals in a digital oscilloscope, which comprises the following steps: firstly, controlling a memory to store sampling data and record the initial position of the storage of the sampling data by using a trigger module, and reading the data from the memory by an upper computer according to the initial position and dividing the data into two paths, one path is displayed through a time domain display window; according to a display mode set by the digital oscilloscope, panoramic analysis and real-time display are carried out through the panoramic analysis module, and detail analysis and real-time display are carried out through the detail analysis module; in this way, the problem that multi-domain analysis cannot be carried out on signals in the measurement process or panorama and details cannot be taken into consideration when multi-domain analysis is carried out is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of digital oscilloscopes, and more specifically, relates to a multi-domain synchronous real-time analysis and display method for complex signals in a digital oscilloscope. Background Art

[0002] In actual measurement, it is sometimes necessary to analyze the signal not only in the time domain, but also in other domains such as the frequency domain and time-frequency domain. The parameters of the signal in different domains and the analysis results are often correlated, and this correlation often reveals the deep characteristics of the signal. In addition, for the analysis of multi-standard signals in the same system, the logical correlation of the parameters of different standard signals at the same time often reveals the inherent characteristics of the system.

[0003] In actual communication test scenarios, testers need to demodulate and analyze a group of modulated signals at the receiving end and observe their frequency band occupancy. Traditional test methods require the use of signal measurement instruments including oscilloscopes and spectrum analyzers to capture this group of signals and draw conclusions after observing them from the time domain, frequency domain, modulation domain and other dimensions. In order to test whether the signal meets the transmission requirements after modulation and before transmission, it is necessary to measure the signal-to-noise ratio and modulation parameters of the signal. The spectrum analyzer can easily obtain the signal-to-noise ratio of the transmitted signal, but it cannot observe the overall shape and quality of the signal from the perspective of the time domain. Using a digital oscilloscope can observe the time domain waveform of the measured signal at a certain time resolution, but it is not easy to obtain the frequency domain parameters of the signal. Traditional digital oscilloscopes do not have signal demodulation functions, so the information that can be obtained is very limited. It can only be inferred whether the modulation type of the signal is amplitude modulation or frequency modulation. If you want to dig deeper information, such as the relationship between the amplitude or frequency of the modulated signal and time, the modulation depth of the amplitude modulated signal, and the frequency offset of the frequency modulated signal, you also need a variety of test instruments. The cumbersome measurement parameter configuration and the low time correlation of the instrument due to physical separation will greatly affect the accuracy of the test results, resulting in inaccurate analysis conclusions.

[0004] Currently, there is no instrument capable of analyzing these correlations, and there are almost no patents involving multi-domain analysis methods. There are only studies on single-domain analysis methods, such as various parameter measurement methods in the time domain, real-time broadband spectrum methods in the frequency domain, time-frequency analysis methods in the time-frequency domain, demodulation methods in the modulation domain, etc. There is no method that can analyze multiple domains simultaneously. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a multi-domain synchronous real-time analysis and display method for complex signals in a digital oscilloscope. The multi-domain analysis method of signals based on digital down-conversion can realize multi-domain synchronous real-time panoramic and detailed analysis of the digital oscilloscope, so that the measured signal can be analyzed in depth in multiple dimensions at the same time.

[0006] To achieve the above-mentioned object of the invention, the present invention provides a multi-domain synchronous real-time analysis and display method for complex signals in a digital oscilloscope, characterized in that it comprises the following steps:

[0007] (1) Power on the digital oscilloscope and connect it to the measured signal, turn on the write enable of the memory in the digital oscilloscope, and set the display mode of the digital oscilloscope: real-time display of panoramic analysis or real-time display of detailed analysis;

[0008] (2) The measured signal is collected by the acquisition system of the digital oscilloscope to obtain N parallel sampling data, and then the N parallel sampling data are divided into two paths, one of which is sent to the memory and the other is sent to the trigger module;

[0009] (3) In the trigger module, the parallel N-channel sampling data is passed through the parallel data comparator to obtain N-channel trigger comparison signals, and then the N-channel trigger comparison signals are monitored. If any of the trigger comparison signals is at a high level, a trigger signal is generated and fed back to the memory;

[0010] (4) When the memory detects the rising edge of the trigger signal, it records the location of the current sampled data storage in the memory and uses it as the timestamp P trig ; Then the memory is timestamped P trig The calculation starts from the starting address, and the sampling data with a record length of D is used as the multi-domain analysis data, where D is the time domain display window length of the host computer;

[0011] (5) Real-time and synchronous display of multi-domain analysis data;

[0012] (5.1) The host computer reads the multi-domain analysis data from the memory, and then divides it into two paths through the parallel splitter A. One path of the multi-domain analysis data is displayed in the time domain through the time domain display window of the host computer after parallel-to-serial conversion, extraction, correction and interpolation processing; the other path of the multi-domain analysis data is sent to the multi-domain analysis module;

[0013] (5.2), the multi-domain analysis data is divided into two paths through the parallel splitter B, one path of the multi-domain analysis data is sent to the panoramic analysis module, and then goes to step (5.3); the other path of the multi-domain analysis data is sent to the detail analysis module, and then goes to step (5.4);

[0014] (5.3) Panoramic analysis and real-time display;

[0015] (5.3.1), the multi-domain analysis data is converted into serial data by a parallel-to-serial converter B;

[0016] (5.3.2) When the display mode of the digital oscilloscope is set to panoramic analysis real-time display, the data selector C selects the serial data to be stored in the data buffer;

[0017] (5.3.3), the short-time Fourier transform module reads serial data from the data buffer and performs short-time Fourier transform to obtain multi-frame FFT data;

[0018] (5.3.4) The host computer draws each frame of FFT data into a spectrum diagram, and then displays each spectrum diagram in the frequency domain through the frequency domain display window of the host computer; in addition, the host computer superimposes each frame of FFT data in the time axis direction, and converts the amplitude value into a color value and then draws it into a time-frequency diagram and a time / frequency / amplitude three-dimensional stereogram, and then displays the time-frequency diagram in the time-frequency domain through the time-frequency domain display window of the host computer, and displays the time / frequency / amplitude three-dimensional stereogram in the time / frequency / amplitude three-dimensional display window;

[0019] (5.4) Real-time display of detailed analysis;

[0020] (5.4.1) The multi-domain analysis data is divided into two paths through the parallel splitter C, one path of the multi-domain analysis data is input to the mixer I, and the other path of the multi-domain analysis data is input to the mixer Q;

[0021] (5.4.2) The N-channel parallel direct frequency synthesizer DDS generates N-channel parallel sine signals and N-channel parallel cosine signals, and then inputs the N-channel parallel cosine signals to mixer I, and inputs the N-channel parallel sine signals to mixer Q;

[0022] (5.4.3) The mixer I mixes the multi-domain analysis data and the N-channel parallel cosine signals to obtain N-channel parallel I data; the N-channel parallel I data is divided into two channels by the parallel splitter D, one channel is sent to the parallel-serial conversion module C to be converted into serial I data; the other channel is sent to the parallel extraction filter structure for parallel extraction filtering to obtain serial extracted I data; then the serial I data and the serial extracted I data are selected and outputted by the data selector A, and the output result is inputted into the serial extraction filter structure for serial extraction filtering to obtain the final serial I data;

[0023] (5.4.4), the mixer Q mixes the multi-domain analysis data and the N parallel sinusoidal signals to obtain N parallel Q data; the N parallel Q data are divided into two paths by the parallel splitter E, one path is sent to the parallel-serial conversion module D to be converted into serial Q data; the other path is sent to the parallel extraction filter structure for parallel extraction filtering to obtain serial extracted Q data; then the serial Q data and the serial extracted Q data are selected and outputted by the data selector B, and the output result is inputted into the serial extraction filter structure for serial extraction filtering to obtain the final serial Q data;

[0024] (5.4.5) When the display mode of the digital oscilloscope is set to detailed analysis real-time display, the data selector C selects the serial I and Q data to be stored in the data buffer;

[0025] (5.4.6) According to steps (5.3.3) to (5.3.4), the short-time Fourier transform module reads the serial I and Q data from the data cache and processes and displays them; at the same time, the amplitude / phase / frequency calculation module reads the serial I and Q data from the data cache, calculates the amplitude / phase / frequency discrete sequence, and plots the discrete sequence into an amplitude-time curve, a phase-time curve, and a frequency-time curve, and then displays them in the modulation domain through the modulation domain display window of the host computer.

[0026] The object of the invention of the present invention is achieved in this way:

[0027] The present invention discloses a multi-domain synchronous real-time analysis and display method for complex signals in a digital oscilloscope. Firstly, a trigger module is used to control a memory to store sampled data and record the starting position of the sampled data storage. A host computer reads data from the memory according to the starting position and divides the data into two paths, one of which is displayed through a time domain display window; the other path is sent to a multi-domain analysis module. According to the display mode set by the digital oscilloscope, a panoramic analysis module is used to perform a panoramic analysis and real-time display, and a detail analysis module is used to perform a detail analysis and real-time display. In this way, the problem that a signal cannot be multi-domain analyzed during a measurement process or that the panoramic view and the detail cannot be considered at the same time when the multi-domain analysis is performed is solved.

[0028] At the same time, the multi-domain synchronous real-time analysis and display method of complex signals in a digital oscilloscope of the present invention also has the following beneficial effects:

[0029] (1) Through panoramic analysis, the characteristic information within the full bandwidth of the signal can be quickly obtained;

[0030] (2) Detailed analysis shows that local fine analysis of the signal features of interest can be performed;

[0031] (3) Through the panoramic and detailed display of multi-domain information of the signal, a single digital oscilloscope can build a more complete test system and perform multi-dimensional and in-depth analysis of the measured signal at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a principle block diagram of a multi-domain synchronous real-time analysis and display method of complex signals in a digital oscilloscope of the present invention;

[0033] Figure 2 yes Figure 1 The structural diagram of the short-time Fourier transform module shown;

[0034] Figure 3 It is a rendering of the real-time display of multi-domain panoramic analysis;

[0035] Figure 4 yes Figure 1 The block diagram of the parallel mixer shown;

[0036] Figure 5 It is the block diagram of the parallel CIC filter;

[0037] Figure 6 It is the block diagram of the parallel half-band filter;

[0038] Figure 7 It is the block diagram of the serial CIC filter;

[0039] Figure 8 It is a rendering of the real-time display of multi-domain detail analysis. DETAILED DESCRIPTION

[0040] The specific implementation of the present invention is described below in conjunction with the accompanying drawings so that those skilled in the art can better understand the present invention. It should be noted that in the following description, when the detailed description of known functions and designs may dilute the main content of the present invention, these descriptions will be omitted here.

[0041] Example

[0042] In this embodiment, if Figure 1 As shown, the present invention provides a multi-domain synchronous real-time analysis and display method for complex signals in a digital oscilloscope, comprising the following steps:

[0043] (1) The digital oscilloscope is powered on and connected to the measured signal. The measured signal is a frequency modulated signal with a carrier frequency of 50 MHz, a modulation frequency of 50 kHz, a frequency deviation of 10 MHz, and a modulation type of sine.

[0044] Enable the write function of the memory in the digital oscilloscope, set the display mode of the digital oscilloscope: real-time display of panoramic analysis or real-time display of detailed analysis, set the time base and amplitude of the time domain display window of the digital oscilloscope according to the measured signal, and select the appropriate window function type;

[0045] (2) The sampling rate of the digital oscilloscope is 20 GSPS, and the bandwidth is 8 GHz. The measured signal input to the digital oscilloscope is collected and received using a 250 MHz clock to obtain 80 parallel sampling data. The 80 parallel sampling data are then divided into two paths, one of which is sent to the memory, and the other is sent to the trigger module.

[0046] (3) In the trigger module, the 80 parallel sampling data are passed through the parallel data comparator to obtain 80 trigger comparison signals, and then the 80 trigger comparison signals are monitored. If any of the trigger comparison signals is at a high level, a trigger signal is generated and fed back to the memory;

[0047] (4) When the memory detects the rising edge of the trigger signal, it records the location of the current sampled data storage in the memory and uses it as the timestamp P trig ; Then the memory is timestamped P trig The calculation starts from the starting address, and the sampling data with a record length of D is used as the multi-domain analysis data, where D is the time domain display window length of the host computer;

[0048] (5) Real-time and synchronous display of multi-domain analysis data;

[0049] (5.1) The host computer reads the multi-domain analysis data from the memory, and then divides it into two paths through the parallel splitter A. One path of the multi-domain analysis data is displayed in the time domain through the time domain display window of the host computer after parallel-to-serial conversion, extraction, correction and interpolation processing; the other path of the multi-domain analysis data is sent to the multi-domain analysis module;

[0050] (5.2), the multi-domain analysis data is divided into two paths through the parallel splitter B, one path of the multi-domain analysis data is sent to the panoramic analysis module, and then goes to step (5.3); the other path of the multi-domain analysis data is sent to the detail analysis module, and then goes to step (5.4);

[0051] (5.3) Panoramic analysis and real-time display;

[0052] (5.3.1) The multi-domain analysis data is converted into serial data by a parallel-to-serial converter B. The serial data at this time contains the characteristic information of the signal within the full bandwidth, but the frequency resolution is low;

[0053] (5.3.2) When the display mode of the digital oscilloscope is set to panoramic analysis real-time display, the analysis bandwidth of the frequency domain display window is set to full bandwidth 8 GHz, the FFT length of the frequency domain analysis window is set to L = 1024, the window function moving step of the short-time Fourier transform module is set to S = 16, and the data selector C selects serial data A to be stored in the data cache;

[0054] (5.3.3), the short-time Fourier transform module reads serial data from the data buffer and performs short-time Fourier transform to obtain multi-frame FFT data;

[0055] In this embodiment, the structure of the short-time Fourier transform module is as follows: Figure 2 As shown, it is assumed that the length of each FFT calculation is L, and the moving step of the window function of the short-time Fourier transform is S;

[0056] When the first frame of data is transmitted, the data cache outputs L data to the RAM, and the data is stored in sequence starting from address 0. At this time, the data in the RAM are D0, D1, D2, ..., D L-1 , a total of L pairs of I and Q data;

[0057] When performing FFT operation on the first frame of data, the subsequent FFT module reads the data in the RAM from address 0 to address L-1. The read data are D0, D1, D2, ..., D L-1 ;

[0058] When the second frame of data is transmitted, the data cache transmits S data to the RAM. The RAM starts writing from address 0 and finishes writing to address S-1, overwriting the data stored in the previous frame of this address. After the writing is completed, the data in the RAM are D L , D L+1 , D L+2 , …, D L+S-1 , D S , D S+1 , …, D L-1 , a total of L pairs of I and Q data;

[0059] When performing FFT calculation on the second frame of data, the post-stage FFT module reads the data in the RAM in sequence starting from address S. When the read address exceeds L and the number of data is less than L, it returns to address 0 and reads the data in sequence. The read data is D S , D S+1 , …, D L-1 , D L , D L+1 , D L+2 , …, D L+S-1 ;

[0060] When reading data from RAM, the window function coefficients W0, W1, W2, ..., W are read from RAM at the same time. L-1 , the data and coefficients are multiplied by the multiplier and then sent to FFT, and finally L frames of FFT data are obtained;

[0061] (5.3.4) The host computer draws each frame of FFT data into a spectrum diagram, and then displays each spectrum diagram in the frequency domain through the frequency domain display window of the host computer; in addition, the host computer superimposes each frame of FFT data in the time axis direction, and converts the amplitude value into a color value and then draws it into a time-frequency diagram and a time / frequency / amplitude three-dimensional stereogram, and then displays the time-frequency diagram in the time-frequency domain through the time-frequency domain display window of the host computer, and displays the time / frequency / amplitude three-dimensional stereogram in the time / frequency / amplitude three-dimensional display window;

[0062] In this embodiment, all the results of the panoramic analysis displayed in real time are as follows Figure 3 As shown in the figure, the distribution of signals within the full bandwidth can be observed through panoramic analysis, but the resolution of the signal's frequency domain information and time-frequency domain information is low;

[0063] (5.4) Real-time display of detailed analysis;

[0064] (5.4.1) The multi-domain analysis data is divided into two paths through the parallel splitter C, one path of the multi-domain analysis data is input to the mixer I, and the other path of the multi-domain analysis data is input to the mixer Q;

[0065] (5.4.2) The 80-channel parallel direct frequency synthesizer DDS generates 80 parallel sine signals and N parallel cosine signals, and then inputs the 80 parallel cosine signals to mixer I, and inputs the 80 parallel sine signals to mixer Q;

[0066] In this embodiment, in order to process the front-end high-speed sampling data, it is necessary to adopt real-time mixing technology. Figure 4 The structural block diagram of the real-time mixing technology is shown. The frequency domain display window mixing frequency is set to 50MHz, the analysis bandwidth is set to 50MHz, the short-time Fourier transform module FFT length is set to 256, and the window function moving step is set to 16; each channel of input data is multiplied by the sine and cosine signals output by the DDS to obtain the I and Q results of each channel of mixing;

[0067] (5.4.3) The mixer I mixes the multi-domain analysis data and the 80 parallel cosine signals to obtain 80 parallel I data; the 80 parallel I data are divided into two paths by the parallel splitter D, one of which is sent to the parallel-serial conversion module C to be converted into serial I data; the other is sent to the parallel extraction filter structure for parallel extraction filtering to obtain serial extraction I data;

[0068] In this embodiment, in order to process high-speed sampling data in real time, a parallel decimation filtering technique is required. The parallel decimation filtering structure is composed of a parallel CIC filter and a parallel half-band filter. Figure 5 As shown, the parallel CIC filter is composed of a cascaded parallel integrator, a parallel decimator and a cascaded parallel comb filter; the parallel integrator and the parallel comb filter have the same cascaded number of stages, which can be determined according to the stopband attenuation index required by the design, and the decimation number R=40; after 80 parallel I data pass through the parallel CIC filter, 2 parallel I data are obtained;

[0069] like Figure 6 As shown, the structure of the parallel half-band filter includes parallel data splitting, FIR filter, delay and shift, and after the two-way parallel I data pass through the parallel half-band filter, serial I data is obtained;

[0070] Then the serial I data and the serial decimation I data are selected and outputted through the data selector A, and the output result is inputted into the serial decimation filter structure for serial decimation filtering to obtain the final serial I data;

[0071] In this embodiment, the serial decimation filter structure is composed of a serial CIC filter and a serial half-band filter. Figure 7 As shown, the serial CIC filter is composed of a serial integrator, a serial decimator and a serial comb filter. The number of cascaded stages of the serial integrator and the serial comb filter is the same, and the number of cascaded stages can be determined according to the stopband attenuation index required by the design; the serial half-band filter is essentially a serial FIR filter, and the half-band filter coefficient can be determined according to the stopband attenuation index required by the design;

[0072] (5.4.4), the mixer Q mixes the multi-domain analysis data and 80 parallel sinusoidal signals to obtain 80 parallel Q data; the 80 parallel Q data are divided into two paths by the parallel splitter E, one path is sent to the parallel-serial conversion module D to be converted into serial Q data; the other path is sent to the parallel extraction filter structure for parallel extraction filtering to obtain serial extracted Q data; then the serial Q data and the serial extracted Q data are selected and outputted by the data selector B, and the output result is input into the serial extraction filter structure for serial extraction filtering to obtain the final serial Q data;

[0073] (5.4.5) When the display mode of the digital oscilloscope is set to detailed analysis real-time display, the data selector C selects the serial data I and Q to be stored in the data buffer;

[0074] (5.4.6) According to steps (5.3.3) to (5.3.4), the short-time Fourier transform module reads the serial I and Q data from the data cache and processes and displays them; at the same time, the amplitude / phase / frequency calculation module reads the serial I and Q data from the data cache, calculates the amplitude / phase / frequency discrete sequence, plots the discrete sequence into an amplitude-time curve, a phase-time curve, and a frequency-time curve, and then displays the modulation domain through the modulation domain display window of the host computer;

[0075] In this embodiment, all results displayed in real time by detailed analysis are as follows Figure 8 As shown in the figure, after detailed analysis, the distribution of signals in a specific frequency band can be observed. The frequency domain display window of the signal can be used to observe the range of signal frequency changes, and the frequency resolution is relatively high. The time-frequency domain display window can be used to observe the form of the modulation signal frequency changing over time. The time / frequency / amplitude three-dimensional display window can be used to observe the overall and detailed changes in the signal time, frequency and amplitude. The modulation domain display window can be used to observe the changes in the modulation signal amplitude and phase over time, and the signal observation information is richer.

[0076] Finally, after the rising edge of the next cycle of the trigger signal, the process returns to step (4) to continue extracting the next set of multi-domain analysis data for processing and display.

[0077] Although the above describes the illustrative specific embodiments of the present invention to facilitate those skilled in the art to understand the present invention, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. A multi-domain synchronous real-time analysis and display method for complex signals in a digital oscilloscope, characterized in that: The following steps are involved: (1) Power on the digital oscilloscope and connect it to the measured signal, turn on the write enable of the memory in the digital oscilloscope, and set the display mode of the digital oscilloscope: real-time display of panoramic analysis or real-time display of detailed analysis; (2) The measured signal is collected by the acquisition system of the digital oscilloscope to obtain N parallel sampling data, and then the N parallel sampling data are divided into two paths, one of which is sent to the memory and the other is sent to the trigger module; (3) In the trigger module, the parallel N-channel sampling data is passed through the parallel data comparator to obtain N-channel trigger comparison signals, and then the N-channel trigger comparison signals are monitored. If any of the trigger comparison signals is at a high level, a trigger signal is generated and fed back to the memory; (4) When the memory detects the rising edge of the trigger signal, it records the location of the current sampled data storage in the memory and uses it as the timestamp P trig ; Then the memory is timestamped P trig The calculation starts from the starting address, and the sampling data with a record length of D is used as the multi-domain analysis data, where D is the time domain display window length of the host computer; (5) Real-time and synchronous display of multi-domain analysis data; (5.1) The host computer reads the multi-domain analysis data from the memory, and then divides it into two paths through the parallel splitter A. One path of the multi-domain analysis data is displayed in the time domain through the time domain display window of the host computer after parallel-to-serial conversion, extraction, correction and interpolation processing; the other path of the multi-domain analysis data is sent to the multi-domain analysis module; (5.2), the multi-domain analysis data is divided into two paths through the parallel splitter B, one path of the multi-domain analysis data is sent to the panoramic analysis module, and then goes to step (5.3); the other path of the multi-domain analysis data is sent to the detail analysis module, and then goes to step (5.4); (5.3) Panoramic analysis and real-time display; (5.3.1), the multi-domain analysis data is converted into serial data by a parallel-to-serial converter B; (5.3.2) When the display mode of the digital oscilloscope is set to panoramic analysis real-time display, the data selector C selects the serial data to be stored in the data buffer; (5.3.3), the short-time Fourier transform module reads serial data from the data buffer and performs short-time Fourier transform to obtain multi-frame FFT data; (5.3.4) The host computer draws each frame of FFT data into a spectrum diagram, and then displays each spectrum diagram in the frequency domain through the frequency domain display window of the host computer; in addition, the host computer superimposes each frame of FFT data in the time axis direction, and converts the amplitude value into a color value and then draws it into a time-frequency diagram and a time / frequency / amplitude three-dimensional stereogram, and then displays the time-frequency diagram in the time-frequency domain through the time-frequency domain display window of the host computer, and displays the time / frequency / amplitude three-dimensional stereogram in the time / frequency / amplitude three-dimensional display window; (5.4) Real-time display of detailed analysis; (5.4.1) The multi-domain analysis data is divided into two paths through the parallel splitter C, one path of the multi-domain analysis data is input to the mixer I, and the other path of the multi-domain analysis data is input to the mixer Q; (5.4.2) The N-channel parallel direct frequency synthesizer DDS generates N-channel parallel sine signals and N-channel parallel cosine signals, and then inputs the N-channel parallel cosine signals to mixer I, and inputs the N-channel parallel sine signals to mixer Q; (5.4.3) The mixer I mixes the multi-domain analysis data and the N-channel parallel cosine signals to obtain N-channel parallel I data; the N-channel parallel I data is divided into two channels by the parallel splitter D, one channel is sent to the parallel-serial conversion module C to be converted into serial I data; the other channel is sent to the parallel extraction filter structure for parallel extraction filtering to obtain serial extracted I data; then the serial I data and the serial extracted I data are selected and outputted by the data selector A, and the output result is inputted into the serial extraction filter structure for serial extraction filtering to obtain the final serial I data; (5.4.4), the mixer Q mixes the multi-domain analysis data and the N parallel sinusoidal signals to obtain N parallel Q data; the N parallel Q data are divided into two paths by the parallel splitter E, one path is sent to the parallel-serial conversion module D to be converted into serial Q data; the other path is sent to the parallel extraction filter structure for parallel extraction filtering to obtain serial extracted Q data; then the serial Q data and the serial extracted Q data are selected and outputted by the data selector B, and the output result is inputted into the serial extraction filter structure for serial extraction filtering to obtain the final serial Q data; (5.4.5) When the display mode of the digital oscilloscope is set to detailed analysis real-time display, the data selector C selects the serial I and Q data to be stored in the data buffer; (5.4.6) According to steps (5.3.3) to (5.3.4), the short-time Fourier transform module reads the serial I and Q data from the data cache and processes and displays them; at the same time, the amplitude / phase / frequency calculation module reads the serial I and Q data from the data cache, calculates the amplitude / phase / frequency discrete sequence, and plots the discrete sequence into an amplitude-time curve, a phase-time curve, and a frequency-time curve, and then displays them in the modulation domain through the modulation domain display window of the host computer.

2. The method for multi-domain synchronous real-time analysis and display of complex signals in a digital oscilloscope according to claim 1, characterized in that: The parallel decimation filter structure is composed of a parallel CIC filter and a parallel half-band filter.

3. The method for multi-domain synchronous real-time analysis and display of complex signals in a digital oscilloscope according to claim 1, characterized in that: The serial decimation filter structure is composed of a serial CIC filter and a serial half-band filter.

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