Broadband signal real-time spectrum analysis system, method and device and storage medium

Abstract

The invention provides a broadband signal real-time spectrum analysis system, method and device and a storage medium, the real-time spectrum analysis system comprises at least three paths of Talbot frequency-time mapping modules, the repetition frequency of the optical pulse sequence of each path of pulse light source is sequentially increased according to the fixed frequency increment, the same radio frequency signal to be detected is converted into three paths of electric signals with different delay time; and the digital signal processing module is used for calculating the real frequency of the radio frequency signal to be measured according to the three paths of electric signals with different delay time. According to the broadband signal real-time spectrum analysis system, method and device and the storage medium, broadband, unambiguous and multi-source frequency measurement can be realized.

Description

Technical Field

[0001] This application relates to the fields of microwave photonics and optoelectronic detection technology, and in particular to broadband signal real-time spectrum analysis systems, methods, devices, and storage media. Background Technology

[0002] With the development of radar detection, electronic countermeasures, and broadband communication technologies, the instantaneous bandwidth of the radio frequency signals under test is constantly increasing, and the frequency range can cover tens of GHz or even higher. Traditional pure electric solutions are limited by the sampling rate and bandwidth of analog-to-digital converters, making it difficult to balance high bandwidth, high resolution, and real-time performance. Microwave photonics utilizes the high bandwidth and low loss characteristics of optical carriers to perform high-speed signal processing and spectrum analysis in the optical domain, becoming an important approach to achieving broadband frequency measurement.

[0003] The Talbot-based frequency-to-time mapping scheme maps the spectral information of a radio frequency signal onto the time waveform of light intensity by performing dispersion broadening and Talbot shaping on a periodic optical pulse sequence. Spectral analysis and frequency measurement can then be achieved through photoelectric detection and sampling. This type of system is compact, easily achieving high resolution and high dynamic range, and has become a research hotspot in recent years.

[0004] However, existing Talbot spectrum analysis and Talbot frequency measurement schemes generally use a single pulse repetition frequency, and their effective non-aliasing measurement bandwidth is usually limited to about half of the pulse repetition frequency. When the frequency of the RF signal under test exceeds this Nyquist bandwidth, high-frequency components will fold back into the baseband, causing different true frequencies to correspond to the same time position or alias frequency, resulting in frequency aliasing and folding ambiguity. Especially in scenarios involving the RF signal under test or multiple targets, it is difficult to uniquely determine the true position of each frequency component using only a single Talbot output. Existing schemes are often only effective for single-frequency or narrowband signals, making it difficult to achieve wideband, multi-source, unambiguous frequency measurement.

[0005] On the other hand, existing literature proposes multi-comb, multi-repetition-frequency downsampling schemes that can utilize multiple sets of beat frequencies generated by different repetition frequencies to recover the true frequency through methods such as integer properties, solution space partitioning, and remainder matching, thus expanding the unambiguous measurement range. However, such schemes usually rely on multi-combs or complex optical downconversion structures, making them difficult to implement, and they are mostly designed for beat frequency signal processing, without being combined with Talbot frequency-time mapping.

[0006] Therefore, existing technologies urgently need a new Talbot frequency measurement scheme that, while maintaining a relatively simple system structure, introduces the concepts of multiple sampling rates and dealiasing to solve the frequency aliasing and folding ambiguity problems of single-sampling-rate Talbot systems under high-frequency and multi-frequency conditions, thereby achieving broadband, unambiguous, and multi-source frequency measurement. Summary of the Invention

[0007] In view of the shortcomings of the prior art, the purpose of this application is to provide a broadband signal real-time spectrum analysis system, method, device and storage medium to solve the frequency aliasing and folding ambiguity problems of single sampling rate Talbot system under high frequency and multi-frequency conditions, and realize broadband, unambiguous and multi-source frequency measurement.

[0008] In a first aspect, this application provides a real-time spectrum analysis system for broadband signals, wherein the broadband signal includes a radio frequency signal under test, and the real-time spectrum analysis system includes: The Talbot frequency-time mapping module includes a pulsed light source, an electro-optic modulator, a dispersive element, and a photodetector connected in sequence. It is used to convert the radio frequency signal under test into an electrical signal, and the delay time of the electrical signal corresponds to the frequency of the radio frequency signal under test. The digital signal processing module is used to convert the delay time of the electrical signal into a folding frequency and calculate the true frequency of the radio frequency signal under test based on the folding frequency. The Talbot frequency-time mapping module is configured with at least three channels. The repetition frequency of the light pulse sequence of each pulse light source increases sequentially according to a fixed frequency increment, so as to convert the same radio frequency signal under test into three electrical signals with different delay times. The digital signal processing module calculates the true frequency of the radio frequency signal under test based on the three electrical signals with different delay times.

[0009] In one implementation of the first aspect, the repetition frequency is at least 20 times the fixed frequency increment.

[0010] In one implementation of the first aspect, the dispersive element is one or more of a dispersive fiber, a chirped fiber grating, or an integrated dispersive waveguide.

[0011] In one implementation of the first aspect, the electro-optic modulator is an intensity modulator, a Mach-Zehnder modulator, or a phase modulator.

[0012] Secondly, this application provides a real-time spectrum analysis method for broadband signals, applied to a real-time spectrum analysis system for broadband signals. The broadband signal is a single-frequency signal, with three successively increasing repetition frequencies being the third repetition frequency, the first repetition frequency, and the second repetition frequency, respectively. The corresponding folding frequencies are the third folding frequency, the first folding frequency, and the second folding frequency, respectively, and the corresponding folding orders are the third folding order, the first folding order, and the second folding order, respectively. The real-time spectrum analysis method for broadband signals includes: Convert the first folding frequency to the first non-mirror folding frequency: if the second folding frequency is less than the third folding frequency, then the first non-mirror folding frequency is equal to the first folding frequency; if the second folding frequency is greater than the third folding frequency, then the first non-mirror folding frequency is equal to the first repetition frequency minus the first folding frequency. Assume the first fold order is equal to the second fold order or equal to the second fold order plus one; assume the second non-mirror fold frequency is equal to the second fold frequency or equal to the second repetition frequency minus the first fold frequency; thus, four sets of hypothetical parameters are obtained. Using each set of assumed parameters, for the first Talbot frequency-time mapping module and the second Talbot frequency-time mapping module, a system of equations is established based on the fact that the product of the folding order and the repetition frequency plus the folding frequency without mirror equals the true frequency; a total of four systems of equations are obtained. Solving the four systems of equations yields four sets of solutions, each of which includes the first folding order, the first non-mirror folding frequency, the second folding order, and the second non-mirror folding frequency. From the four sets of solutions, the solution with both the first folding order and the second folding order being non-negative integers is selected as the true solution, and the true frequency is calculated using the true solution.

[0013] Thirdly, this application provides a real-time spectrum analysis method for broadband signals, applied to a real-time spectrum analysis system for broadband signals. The broadband signal is a multi-frequency signal, and the real-time spectrum analysis method for broadband signals includes: Select the folding frequency of the RF signal under test from each folding frequency and combine them to obtain at least eight folding frequency combinations; For each combination of folded frequencies, enumerate all possible combinations of folded frequencies without mirror image, traverse all possible folding orders of one path, and obtain the folding orders of the other two paths. For two Talbot frequency-time mapping modules with the same folding order, calculate the first difference between the two unmirrored folding frequencies, calculate the second difference between the two repetition frequencies, and calculate the first ratio of the absolute values ​​of the first difference and the second difference. For two Talbot frequency-time mapping modules with different folding orders, calculate the first difference between the two unmirrored folding frequencies; multiply the folding order of one path by the repetition frequency of the other path to obtain the first product; subtract one from the folding order of one path and multiply it by its own repetition frequency to obtain the second product; calculate the third difference between the first product and the second product. If the first ratio is the folding order of the two Talbot frequency-time mapping modules, and the absolute value of the first difference is equal to the absolute value of the third difference, then the folded frequency combination is considered to correspond to the same RF signal under test and is retained; otherwise, the folded frequency combination is discarded. Based on the real-time spectrum analysis method for broadband signals, the true frequency of the radio frequency signal under test is calculated using the retained folded frequency combination.

[0014] Fourthly, this application provides a real-time spectrum analysis device for broadband signals, applied to a real-time spectrum analysis system for broadband signals. The broadband signal is a single-frequency signal, with three sequentially increasing repetition frequencies being a third repetition frequency, a first repetition frequency, and a second repetition frequency. The corresponding folding frequencies are a third folding frequency, a first folding frequency, and a second folding frequency, and the corresponding folding orders are a third folding order, a first folding order, and a second folding order. The real-time spectrum analysis device for broadband signals includes: The mirror frequency identification module is used to convert the first folding frequency into the first non-mirror folding frequency: if the second folding frequency is less than the third folding frequency, then the first non-mirror folding frequency is equal to the first folding frequency; if the second folding frequency is greater than the third folding frequency, then the first non-mirror folding frequency is equal to the first repetition frequency minus the first folding frequency. The parameter generation module assumes that the first folding order is equal to the second folding order or equal to the second folding order plus one; and that the second non-mirror folding frequency is equal to the second folding frequency or equal to the second repetition frequency minus the first folding frequency; thus obtaining four sets of assumed parameters.

[0015] The equation generation module is used to generate a set of equations for each set of assumed parameters. For the first Talbot frequency-time mapping module and the second Talbot frequency-time mapping module, the product of the folding order and the repetition frequency plus the non-mirror folding frequency equals the true frequency. A total of four sets of equations are obtained. The equation solving module solves four systems of equations, yielding four sets of solutions. Each set of solutions includes the first folding order, the first non-mirror folding frequency, the second folding order, and the second non-mirror folding frequency. The true frequency recovery module selects the solution with both the first and second folding orders being non-negative integers from the four sets of solutions as the true solution, and calculates the true frequency using the true solution.

[0016] Fifthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for real-time spectrum analysis of broadband signals.

[0017] As described above, the broadband signal real-time spectrum analysis system, method, apparatus, and storage medium of this application have the following beneficial effects: The Talbot frequency-time mapping itself has the characteristics of high resolution and high dynamic range. Combined with the multi-sampling rate non-aliasing extension of this application, broadband real-time spectrum analysis and frequency measurement can be achieved while maintaining resolution, realizing an unambiguous measurement range far exceeding the single-path Nyquist bandwidth. Simultaneously, it can also achieve real-time spectrum analysis of the RF signal under test, enabling high-accuracy true frequency recovery. Attached Figure Description

[0018] Figure 1 The diagram shown is a schematic representation of a real-time spectrum analysis system for broadband signals according to an embodiment of this application.

[0019] Figure 2 The flowchart shown is a method for real-time spectrum analysis of a single-frequency signal according to an embodiment of this application.

[0020] Figure 3 The diagram shown is a schematic diagram of frequency band division in one embodiment of this application.

[0021] Figure 4 The diagram shown is a frequency-time mapping result of a single-frequency signal in one embodiment of this application.

[0022] Figure 5 The flowchart shown is a real-time spectrum analysis method for multi-frequency signals according to an embodiment of this application.

[0023] Figure 6 The diagram shown is a frequency-time mapping result of a multi-frequency signal in one embodiment of this application.

[0024] Figure 7 The diagram shown is a structural schematic of a broadband signal real-time spectrum analysis device according to an embodiment of this application. Detailed Implementation

[0025] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0026] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. Therefore, the drawings only show the components related to this application and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0027] In one embodiment, this application provides a real-time spectrum analysis system for broadband signals, wherein the broadband signal includes a radio frequency signal under test, and the real-time spectrum analysis system includes: The Talbot frequency-time mapping module includes a pulsed light source, an electro-optic modulator, a dispersive element, and a photodetector connected in sequence. It is used to convert the radio frequency signal under test into an electrical signal, and the delay time of the electrical signal corresponds to the frequency of the radio frequency signal under test. The digital signal processing module is used to convert the delay time of the electrical signal into a folding frequency and calculate the true frequency of the radio frequency signal under test based on the folding frequency. The Talbot frequency-time mapping module is configured with at least three channels. The repetition frequency of the light pulse sequence of each pulse light source increases sequentially according to a fixed frequency increment, so as to convert the same radio frequency signal under test into three electrical signals with different delay times. The digital signal processing module calculates the true frequency of the radio frequency signal under test based on the three electrical signals with different delay times.

[0028] The hardware structures of the pulsed light source, electro-optic modulator, dispersive element, photodetector, and digital signal processing module in this embodiment can all employ existing technologies. The process of converting the delay time of the electrical signal into a folding frequency via the digital signal processing module in this embodiment can also employ existing technologies.

[0029] The main improvement of this embodiment is that at least three parallel Talbot frequency-time mapping modules are set, and the repetition frequency of each channel is set to increase sequentially in small fixed frequency increments.

[0030] In one embodiment, the pulsed light source is a mode-locked laser, a pulsed fiber laser, or an optical comb source. Its output pulse repetition frequency is adjustable or can be externally modulated to achieve different effective sampling frequencies.

[0031] In one embodiment, the electro-optic modulator is an intensity modulator, a Mach-Zehnder modulator, or a phase modulator.

[0032] In one embodiment, the dispersive element is one or more of a dispersive fiber, a chirped fiber grating, or an integrated dispersive waveguide.

[0033] In one embodiment, the group velocity dispersion parameter of the dispersive element and the corresponding Talbot order satisfy the Talbot frequency-time mapping condition. This ensures that different frequency components are monotonically arranged on the time axis within their respective sampling frequency Nyquist bandwidth, thereby completing the frequency-time mapping.

[0034] In one embodiment, the digital signal processing module is an FPGA or a DSP.

[0035] In one embodiment, the repetition frequency is at least 20 times the fixed frequency increment.

[0036] Please refer to Figure 1 In one embodiment, the three-channel Talbot frequency-time mapping module includes: a first-channel Talbot frequency-time mapping module, a second-channel Talbot frequency-time mapping module, and a third-channel Talbot frequency-time mapping module.

[0037] The first Talbot frequency-time mapping module includes a first pulse light source 1, a first electro-optic modulator 5, a first dispersive element 8, and a first photodetector 11 connected in sequence. The second Talbot frequency-time mapping module includes a second pulse light source 2, a second electro-optic modulator 6, a second dispersive element 9, and a second photodetector 12 connected in sequence. The third Talbot frequency-time mapping module includes a third pulse light source 3, a third electro-optic modulator 7, a third dispersive element 10, and a third photodetector 13 connected in sequence.

[0038] The first pulse source 1 emits a first light pulse sequence, the repetition frequency of which is... .

[0039] The second pulse source 2 emits a second light pulse sequence, the repetition frequency of which is... .

[0040] The third pulse source 3 emits a third light pulse sequence, the repetition frequency of which is... .

[0041] The repetition frequencies of the third, first, and second light pulse sequences increase by a fixed frequency. Increasing sequentially, that is , .

[0042] The radio frequency signal under test (RF signal 4) is loaded onto a first optical pulse sequence via a first electro-optic modulator 5 to generate a first modulated signal. The first modulated signal is processed by a first dispersive element 8 and a first photodetector 11 to obtain a first electrical signal. The RF signal under test 4 is then loaded onto a second optical pulse sequence via a second electro-optic modulator 6 to generate a second modulated signal. The second modulated signal is processed by a second dispersive element 9 and a second photodetector 12 to obtain a second electrical signal. The RF signal under test 4 is then loaded onto a third optical pulse sequence via a third electro-optic modulator 7 to generate a third modulated signal. The third modulated signal is processed by a third dispersive element 10 and a third photodetector 13 to obtain a third electrical signal. The first, second, and third electrical signals are three electrical signals with different delay times. The frequency-time mapping relationship of the RF signal under test is as follows: .

[0043] The digital signal processing module 14 extracts the delay time of the first electrical signal and converts the delay time of the first electrical signal into a first folding frequency. The digital signal processing module 14 extracts the delay time of the second electrical signal and converts the delay time of the second electrical signal into a second folding frequency. The digital signal processing module 14 extracts the delay time of the third electrical signal and converts the delay time of the third electrical signal into a third folding frequency. The process of extracting and converting the delay time can refer to existing technologies and is not considered an improvement in this embodiment.

[0044] The digital signal processing module 14 calculates the true frequency of the radio frequency signal under test based on the first folding frequency, the second folding frequency, and the third folding frequency.

[0045] In one embodiment, the first dispersive element 8, the second dispersive element 9, and the third dispersive element 10 satisfy the integer-order Talbot effect, and the dispersion amount satisfies ,in The period of the light pulse sequence ( ).

[0046] Please refer to Figure 2 This application also provides a real-time spectrum analysis method for broadband signals, applied to the real-time spectrum analysis system for broadband signals in the above embodiments. The three sequentially increasing repetition frequencies are the third repetition frequency, the first repetition frequency, and the second repetition frequency, respectively. The corresponding folding frequencies are the third folding frequency, the first folding frequency, and the second folding frequency, respectively, and the corresponding folding orders are the third folding order, the first folding order, and the second folding order, respectively. The real-time spectrum analysis method for broadband signals includes: Step S100: Convert the first folding frequency to a first non-mirror folding frequency: If the second folding frequency is less than the third folding frequency, then the first non-mirror folding frequency is equal to the first folding frequency; if the second folding frequency is greater than the third folding frequency, then the first non-mirror folding frequency is equal to the first repetition frequency minus the first folding frequency. Step S200: Assume that the first folding order is equal to the second folding order or equal to the second folding order plus one; assume that the second non-mirror folding frequency is equal to the second folding frequency or equal to the second repetition frequency minus the first folding frequency; thus obtaining four sets of assumed parameters. Step S300: Using the assumed parameters of each set, for the first Talbot frequency-time mapping module and the second Talbot frequency-time mapping module, according to the product of the folding order and the repetition frequency plus the folding frequency without mirror equals the true frequency, a set of equations is set up; a total of four sets of equations are obtained. Step S400: Solve the four systems of equations to obtain four sets of solutions. Each set of solutions includes the first folding order, the second folding order, and the true frequency. Step S500: Select the solution from the four sets of solutions whose first folding order and second folding order are both non-negative integers as the true solution, and obtain the true frequency.

[0047] Please refer to Figure 3 , Figure 4 The folding frequencies of the three Talbot outputs are obtained through peak detection and mapping. , and ,in , , Since the measured signals are all real signals, their spectrum contains both a positive and a negative frequency component. That is, after down-conversion, the down-converted frequency received in the first half of the first repetition frequency interval may be... or Both conditions are met: (1) definition , and It is the correct downconversion frequency, i.e., the frequency without image folding. , and It is an incorrect mirror negative frequency, i.e., the mirror folding frequency. Frequency calculation is performed primarily using the first and second paths, with the third path used as a secondary method to solve the mirror problem. The following equation can be obtained: (2) in, The actual frequency of the radio frequency signal under test. and The folding order of the same signal in the first and second down-conversion processes. and The repetition frequency of the first and second channels. and The non-mirror folding frequency for the first and second channels.

[0048] The broadband signal real-time spectrum analysis system proposed in this application allows for a maximum measurement range of... The entire frequency band is divided into multiple regions based on different folding orders, such as... Figure 3 As shown, the frequency band of the first path is divided into There are 1 region, and the width of each region is 1. The second channel's frequency band is divided into There are 1 region, and the width of each region is 1. When the frequency of the radio frequency signal under test falls within the red area in the figure, , When the frequency of the radio frequency signal under test falls within the blue area in the figure, , Therefore, we can... Substitute into formula (1) to calculate the true frequency of the radio frequency signal under test. .

[0049] Regarding the image problem, that is, after down-conversion of the signal, the received down-conversion frequency in the first half of the first repetition frequency interval is the correct down-conversion frequency. Still an incorrect mirror frequency This embodiment introduces a third path to determine the mirroring status of the first path, based on a fixed frequency increment between the repetition frequencies of the three optical pulse sequences. The following relationship can be obtained: (3) Similarly, There are also two possibilities. and You only need to put and Substitute these two combinations into formula (4). If... ,but ;if ,but ,because If the integer must be a positive integer, then the right-hand side of formula (4) must also be a positive integer; otherwise, the... It does not exist. It can make The combination of positive integers is the correct combination.

[0050] (4) Finally, combine the correct elements. and Substituting the value into formula (2), the true frequency of the radio frequency signal under test can be calculated, thereby realizing the frequency recovery of the radio frequency signal under test.

[0051] Please refer to Figure 5 This application also provides a real-time spectrum analysis method for broadband signals, applied to the real-time spectrum analysis system for broadband signals in the above embodiments. The broadband signal is a multi-frequency signal, and the real-time spectrum analysis method for broadband signals includes: Step S100: Select a folding frequency of the radio frequency signal under test from each folding frequency and combine them to obtain at least eight folding frequency combinations. Step S200: For each folded frequency combination, enumerate all possible non-mirror folded frequency combinations, traverse all possible folding orders of one path, and obtain the folding orders of the other two paths. Step S300: For two Talbot frequency-time mapping modules with the same folding order, calculate the first difference between the two unmirrored folding frequencies, calculate the second difference between the two repetition frequencies, and calculate the first ratio of the absolute values ​​of the first difference and the second difference. Step S400: For two Talbot frequency-time mapping modules with different folding orders, calculate the first difference between the two unmirrored folding frequencies; multiply the folding order of one channel by the repetition frequency of the other channel to obtain the first product; subtract one from the folding order of one channel and multiply it by its own repetition frequency to obtain the second product; calculate the third difference between the first product and the second product. Step S500: If the first ratio is the folding order of the two Talbot frequency-time mapping modules, and the absolute value of the first difference is equal to the absolute value of the third difference, then the folded frequency combination is considered to correspond to the same radio frequency signal under test and is retained; otherwise, the folded frequency combination is discarded. Step S600: According to the broadband signal real-time spectrum analysis method of the above embodiment, the true frequency of the radio frequency signal under test is calculated by using the retained folded frequency combination.

[0052] Compared to single-frequency signal recovery, multi-frequency signal recovery adds a pairing step, namely, finding folded frequency pairs belonging to the same RF signal under test. For any real frequency The three-way sampling satisfies: (5) because Then the folding order satisfies and define the difference. , , Three correct downconversion frequencies with the same actual frequency. The difference between them is not arbitrary, but is determined by... and integers Constraints. When , When, the difference satisfies formula (6); when , When the difference is equal, the difference satisfies formula (7).

[0053] (6) (7) in, .

[0054] The folding frequency pairs belonging to the same physical signal source are obtained through formulas (6) and (7). Without proper pairing, incorrect combinations can occur, where folded frequencies from different frequency components appear in the same combination, significantly increasing the complexity and increasing the likelihood of errors in subsequent recovery. Therefore, a method for recovering single-frequency signals is used to recover each pair of folded frequency combinations one by one, thereby achieving the recovery of the true frequencies of each tested RF signal in the broadband signal.

[0055] exist Figure 1 The simulation verification of the system shown demonstrates the Talbot frequency-time mapping results for three channels with single-frequency and multi-frequency input signals. The simulation parameters are set as follows: repetition frequencies of the optical pulse sequences are 10 GHz, 11 GHz, and 9 GHz, pulse width is 5 ps, and dispersion is 1591.6. 1315.7 And 1965.5 When the input single-frequency signal has a frequency of 12GHz, the result of the three-channel Talbot frequency-time mapping is as follows: Figure 3 As shown, The folding frequencies are 19.79 ps, 8.31 ps, and 37.83 ps, respectively. The folding frequencies can be calculated using the frequency-time mapping relationship. , and The frequencies are 1.979 GHz, 1.005 GHz, and 3.064 GHz, respectively. When the input multi-frequency signals are 11.7 GHz and 13.1 GHz, the results of the three-channel Talbot frequency-time mapping are as follows: Figure 6 As shown, Figure 6 (a) shows the frequency-time mapping result of the first path. and The values ​​are 16.79 ps and 30.73 ps, respectively. The folding frequency can be calculated from the frequency-time mapping relationship in the time-delay-frequency conversion module. and The frequencies are 1.679 GHz and 3.073 GHz, respectively. Figure 6 (b) shows the frequency-time mapping result of the second path. and The frequencies are 5.84 ps and 17.3 ps respectively. The folding frequency can be calculated from the frequency-time mapping relationship. and The frequencies are 0.706 GHz and 2.093 GHz, respectively. Figure 6 (c) shows the frequency-time mapping result of the third path. and The frequencies are 33.25 ps and 50.69 ps respectively. The folding frequency can be calculated from the frequency-time mapping relationship. and The frequencies are 2.693 GHz and 4.105 GHz, respectively. First, the folded frequencies are paired according to the constraint formulas (6) and (7) to find folded frequency pairs belonging to the same frequency component. The folded frequency pairs corresponding to the frequency 11.7 GHz are (1.679 GHz, 0.706 GHz, 2.693 GHz) and (8.321 GHz, 10.294 GHz, 6.307 GHz); the folded frequency pairs corresponding to the frequency 13.1 GHz are (3.073 GHz, 2.093 GHz, 4.105 GHz) and (6.927 GHz, 8.907 GHz, 4.895 GHz). Then, a dealiasing algorithm is used to exclude fully mirrored combinations, retaining the correct combinations (1.679 GHz, 0.706 GHz, 2.693 GHz) and (3.073 GHz, 2.093 GHz, 4.105 GHz). According to... Figure 3 as well as and Size relationship 1.679GHz 0.706GHz and 3.073GHz 2.093GHz, from which the corresponding frequencies of 11.7GHz and 13.1GHz can be derived. All are 0. Finally, combine the correct combinations. Substituting into formula (2) for calculation, the actual frequencies of the input signals can be calculated as 11.693GHz and 13.083GHz, with errors of 0.007GHz and 0.017GHz, which are negligible.

[0056] As can be seen from the above embodiments, the broadband signal real-time spectrum analysis system proposed in this application features high resolution and high dynamic range. Combined with the multi-sampling rate non-aliasing spread of this application, it can achieve broadband real-time spectrum analysis and frequency measurement while maintaining resolution, achieving an unambiguous measurement range far exceeding the single-path Nyquist bandwidth. Simultaneously, it can also perform spectrum analysis of the RF signal under test, achieving high-accuracy true frequency recovery.

[0057] The scope of protection of the broadband signal real-time spectrum analysis method in this application is not limited to the execution order of the steps listed in this embodiment. Any solution implemented by adding, subtracting, or replacing steps in the prior art based on the principles of this application is included within the scope of protection of this application.

[0058] Please refer to Figure 7 This embodiment provides a real-time spectrum analysis device for broadband signals, applied to the real-time spectrum analysis system for broadband signals described in the above embodiment. The broadband signal is a single-frequency signal, with three sequentially increasing repetition frequencies: a third repetition frequency, a first repetition frequency, and a second repetition frequency. The corresponding folding frequencies are the third folding frequency, the first folding frequency, and the second folding frequency, and the corresponding folding orders are the third folding order, the first folding order, and the second folding order, respectively. The real-time spectrum analysis device for broadband signals includes: The mirror frequency identification module is used to convert the first folding frequency into the first non-mirror folding frequency: if the second folding frequency is less than the third folding frequency, then the first non-mirror folding frequency is equal to the first folding frequency; if the second folding frequency is greater than the third folding frequency, then the first non-mirror folding frequency is equal to the first repetition frequency minus the first folding frequency. The parameter generation module assumes that the first folding order is equal to the second folding order or equal to the second folding order plus one; and that the second non-mirror folding frequency is equal to the second folding frequency or equal to the second repetition frequency minus the first folding frequency; thus obtaining four sets of assumed parameters.

[0059] The equation generation module is used to generate a set of equations for each set of assumed parameters. For the first Talbot frequency-time mapping module and the second Talbot frequency-time mapping module, the product of the folding order and the repetition frequency plus the non-mirror folding frequency equals the true frequency. A total of four sets of equations are obtained. The equation solving module solves four systems of equations, yielding four sets of solutions. Each set of solutions includes the first folding order, the first non-mirror folding frequency, the second folding order, and the second non-mirror folding frequency. The true frequency recovery module selects the solution with both the first and second folding orders being non-negative integers from the four sets of solutions as the true solution, and calculates the true frequency using the true solution.

[0060] In the embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, or methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of modules / units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or units may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection of apparatuses or modules or units may be electrical, mechanical, or other forms.

[0061] The modules / units described as separate components may or may not be physically separate. The components shown as modules / units may or may not be physical modules; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules / units can be selected to achieve the objectives of the embodiments of this application, depending on actual needs. For example, the functional modules / units in the various embodiments of this application may be integrated into one processing module, or each module / unit may exist physically separately, or two or more modules / units may be integrated into one module / unit.

[0062] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0063] In addition, this embodiment also provides a storage medium storing program instructions, which, when executed by a processor, implement the real-time spectrum analysis method for broadband signals in the above embodiments.

[0064] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing a processor, and the program can be stored in a computer-readable storage medium. The storage medium is a non-transitory medium, such as random access memory, read-only memory, flash memory, hard disk, solid-state drive, magnetic tape, floppy disk, optical disk, and any combination thereof. The aforementioned storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., digital video disc (DVD)), or a semiconductor medium (e.g., solid-state disk (SSD)).

[0065] The descriptions of the processes or structures corresponding to the above figures each have their own emphasis. For parts of a process or structure that are not described in detail, please refer to the relevant descriptions of other processes or structures.

[0066] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A real-time spectrum analysis system for broadband signals, wherein the broadband signal includes a radio frequency signal under test, and the real-time spectrum analysis system comprises: The Talbot frequency-time mapping module includes a pulsed light source, an electro-optic modulator, a dispersive element, and a photodetector connected in sequence. It is used to convert the radio frequency signal under test into an electrical signal, and the delay time of the electrical signal corresponds to the frequency of the radio frequency signal under test. The digital signal processing module is used to convert the delay time of the electrical signal into a folding frequency and calculate the true frequency of the radio frequency signal under test based on the folding frequency. The feature is that the Talbot frequency-time mapping module is configured with at least three channels, and the repetition frequency of the light pulse sequence of each pulse light source increases sequentially according to a fixed frequency increment, so as to convert the same radio frequency signal under test into three electrical signals with different delay times. The digital signal processing module calculates the true frequency of the radio frequency signal under test based on the three electrical signals with different delay times.

2. The broadband signal real-time spectrum analysis system according to claim 1, characterized in that, The repetition frequency is at least 20 times the increment of the fixed frequency.

3. The broadband signal real-time spectrum analysis system according to claim 1, characterized in that, The dispersive element is one or more of the following: dispersive fiber, chirped fiber grating, or integrated dispersive waveguide.

4. The broadband signal real-time spectrum analysis system according to claim 1, characterized in that, Electro-optic modulators can be intensity modulators, Mach-Zehnder modulators, or phase modulators.

5. A method for real-time spectrum analysis of broadband signals, applied to the real-time spectrum analysis system for broadband signals according to any one of claims 1 to 4, characterized in that, The broadband signal is a single-frequency signal. The three successively increasing repetition frequencies are the third repetition frequency, the first repetition frequency, and the second repetition frequency, respectively. The corresponding folding frequencies are the third folding frequency, the first folding frequency, and the second folding frequency, respectively, and the corresponding folding orders are the third folding order, the first folding order, and the second folding order, respectively. Real-time spectrum analysis methods for broadband signals include: Convert the first folding frequency to the first non-mirror folding frequency: if the second folding frequency is less than the third folding frequency, then the first non-mirror folding frequency is equal to the first folding frequency; if the second folding frequency is greater than the third folding frequency, then the first non-mirror folding frequency is equal to the first repetition frequency minus the first folding frequency. Assume the first fold order is equal to the second fold order or equal to the second fold order plus one; assume the second non-mirror fold frequency is equal to the second fold frequency or equal to the second repetition frequency minus the first fold frequency; thus, four sets of hypothetical parameters are obtained. Using each set of assumed parameters, for the first Talbot frequency-time mapping module and the second Talbot frequency-time mapping module, a system of equations is established based on the fact that the product of the folding order and the repetition frequency plus the folding frequency without mirror equals the true frequency; a total of four systems of equations are obtained. Solving the four systems of equations yields four sets of solutions, each of which includes the first folding order, the first non-mirror folding frequency, the second folding order, and the second non-mirror folding frequency. From the four sets of solutions, the solution with both the first folding order and the second folding order being non-negative integers is selected as the true solution, and the true frequency is calculated using the true solution.

6. A method for real-time spectrum analysis of broadband signals, applied to the real-time spectrum analysis system for broadband signals according to any one of claims 1 to 4, characterized in that, Broadband signals are multi-frequency signals, and real-time spectrum analysis methods for broadband signals include: Select the folding frequency of the RF signal under test from each folding frequency and combine them to obtain at least eight folding frequency combinations; For each folded frequency combination, enumerate all possible non-mirror folded frequency combinations, traverse all possible folding orders of one path, and obtain the folding orders of the other two paths. For two Talbot frequency-time mapping modules with the same folding order, calculate the first difference between the two unmirrored folding frequencies, calculate the second difference between the two repetition frequencies, and calculate the first ratio of the absolute values ​​of the first difference and the second difference. For two Talbot frequency-time mapping modules with different folding orders, calculate the first difference between the two unmirrored folding frequencies; multiply the folding order of one path by the repetition frequency of the other path to obtain the first product; subtract one from the folding order of one path and multiply it by its own repetition frequency to obtain the second product; calculate the third difference between the first product and the second product. If the first ratio is the folding order of the two Talbot frequency-time mapping modules, and the absolute value of the first difference is equal to the absolute value of the third difference, then the folded frequency combination is considered to correspond to the same RF signal under test and is retained; otherwise, the folded frequency combination is discarded. According to the broadband signal real-time spectrum analysis method of claim 5, the true frequency of the radio frequency signal under test is calculated by using the retained folded frequency combination.

7. A broadband signal real-time spectrum analysis device, applied to the broadband signal real-time spectrum analysis system according to any one of claims 1 to 4, characterized in that, The broadband signal is a single-frequency signal. The three successively increasing repetition frequencies are the third repetition frequency, the first repetition frequency, and the second repetition frequency, respectively. The corresponding folding frequencies are the third folding frequency, the first folding frequency, and the second folding frequency, respectively. The corresponding folding orders are the third folding order, the first folding order, and the second folding order, respectively. The broadband signal real-time spectrum analysis device includes: The mirror frequency identification module is used to convert the first folding frequency into the first non-mirror folding frequency: if the second folding frequency is less than the third folding frequency, then the first non-mirror folding frequency is equal to the first folding frequency; if the second folding frequency is greater than the third folding frequency, then the first non-mirror folding frequency is equal to the first repetition frequency minus the first folding frequency. The parameter generation module assumes that the first folding order is equal to the second folding order or equal to the second folding order plus one; and that the second non-mirror folding frequency is equal to the second folding frequency or equal to the second repetition frequency minus the first folding frequency; thus obtaining four sets of assumed parameters. The equation generation module is used to generate a set of equations for each set of assumed parameters. For the first Talbot frequency-time mapping module and the second Talbot frequency-time mapping module, the product of the folding order and the repetition frequency plus the non-mirror folding frequency equals the true frequency. A total of four sets of equations are obtained. The equation solving module solves four systems of equations, yielding four sets of solutions. Each set of solutions includes the first folding order, the first non-mirror folding frequency, the second folding order, and the second non-mirror folding frequency. The true frequency recovery module selects the solution with both the first and second folding orders being non-negative integers from the four sets of solutions as the true solution, and calculates the true frequency using the true solution.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the real-time spectrum analysis method for broadband signals as described in claim 5.

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