CN-122017344-A - Broadband signal real-time spectrum analysis system, method, device and storage medium

CN122017344ACN 122017344 ACN122017344 ACN 122017344ACN-122017344-A

Abstract

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

Inventors

ZHANG ZHIXUAN
CHI HAO
YANG SHUNA
YANG BO
ZHAI YANRONG
OU JUN

Assignees

杭州电子科技大学

Dates

Publication Date: 20260512
Application Date: 20260112

Claims (8)

1. A broadband signal real-time spectrum analysis system, the broadband signal comprising a radio frequency signal to be measured, the real-time spectrum analysis system comprising: The Talbot frequency-time mapping module comprises a pulse light source, an electro-optical modulator, a dispersion element and a photoelectric detector which are sequentially connected, wherein the Talbot frequency-time mapping module is used for converting a radio frequency signal to be detected into an electric signal, and the delay time of the electric signal corresponds to the frequency of the radio frequency signal to be detected; the digital signal processing module is used for converting the delay time of the electric signal into folding frequency and calculating the real frequency of the radio frequency signal to be detected according to the folding frequency; The method is characterized in that at least three paths of Talbot frequency-time mapping modules are arranged, the repetition frequency of the optical pulse sequences of all paths of pulse light sources is sequentially increased according to fixed frequency increment, so that the same radio frequency signal to be detected is converted into three paths of electric signals with different delay times, and the digital signal processing module calculates the real frequency of the radio frequency signal to be detected according to the three paths of electric signals with different delay times.
2. The broadband signal real-time spectrum analysis system according to claim 1, wherein the repetition frequency is at least 20 times the fixed frequency increment.
3. The broadband signal real-time spectrum analysis system according to claim 1, wherein the dispersive element is one or more of a dispersive optical fiber, a chirped fiber grating, or an integrated dispersive waveguide.
4. The broadband signal real-time spectrum analysis system according to claim 1, wherein the electro-optical modulator is an intensity modulator, a mach-zehnder modulator, or a phase modulator.
5. The method for analyzing the real-time spectrum of the broadband signal is applied to the real-time spectrum analysis system of any one of claims 1 to 4, and is characterized in that the broadband signal is a single-frequency signal, three sequentially increased repetition frequencies are a third repetition frequency, a first repetition frequency and a second repetition frequency respectively, corresponding folding frequencies are a third folding frequency, a first folding frequency and a second folding frequency respectively, corresponding folding orders are the third folding order, the first folding order and the second folding order respectively, and the method for analyzing the real-time spectrum of the broadband signal comprises: Converting the first folding frequency into a first non-mirror folding frequency, wherein the first non-mirror folding frequency is equal to the first folding frequency if the second folding frequency is smaller than the third folding frequency, and the first non-mirror folding frequency is equal to the first repeating frequency minus the first folding frequency if the second folding frequency is larger than the third folding frequency; The first folding order is equal to the second folding order or equal to the second folding order plus one, the second non-mirror folding frequency is equal to the second folding frequency or equal to the second repeating frequency minus the first folding frequency, four groups of hypothetical parameters are obtained; Utilizing each set of hypothesis parameters, and for the first path Talbot frequency-time mapping module and the second path Talbot frequency-time mapping module, adding the non-mirror image folding frequency to be equal to the real frequency according to the product of the folding order and the repetition frequency, and listing one equation set; Solving four equation sets to obtain four solutions, wherein each solution comprises a first folding order, a first non-mirror folding frequency, a second folding order and a second non-mirror folding frequency; and selecting a solution with the first folding order and the second folding order being non-negative integers from the four groups of solutions as a real solution, and calculating by using the real solution to obtain the real frequency.
6. A broadband signal real-time spectrum analysis method 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 multi-frequency signal, and the broadband signal real-time spectrum analysis method comprises: selecting a folding frequency of a radio frequency signal to be tested from the folding frequencies of each path to be combined, so as to obtain at least eight folding frequency combinations; For each folding frequency combination, enumerating all possible non-mirror image folding frequency combinations, traversing all possible folding orders of one path, and obtaining folding orders of the other two paths; For two paths of Talbot frequency-time mapping modules with the same folding order, calculating a first difference value of two paths of non-mirror image folding frequencies, calculating a second difference value of two paths of repeating frequencies, and calculating a first ratio of the absolute value of the first difference value to the absolute value of the second difference value; calculating a first difference value of two paths of non-mirror image folding frequencies for two paths of Talbot frequency-time mapping modules with different folding orders, multiplying the folding order of one path by the repetition frequency of the other path to obtain a first product, subtracting one path of folding order from the repetition frequency of the other path to obtain a second product, and calculating a third difference value of the first product and the second product; If the first ratio is the folding order of the two paths of Talbot frequency-time mapping modules and the absolute value of the first difference is equal to the absolute value of the third difference, the folding frequency combination is considered to correspond to the same radio frequency signal to be detected and is reserved; The method for analyzing the real-time spectrum of the broadband signal according to claim 5, wherein the real frequency of the radio frequency signal to be measured is calculated by using the reserved folding 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, wherein the broadband signal is a single-frequency signal, three sequentially increasing repetition frequencies are a third repetition frequency, a first repetition frequency and a second repetition frequency, corresponding folding frequencies are a third folding frequency, a first folding frequency and a second folding frequency, and corresponding folding orders are the third folding order, the first folding order and the second folding order, respectively, and the broadband signal real-time spectrum analysis device comprises: The image frequency identification module is used for converting the first folding frequency into a first non-image folding frequency, wherein the first non-image folding frequency is equal to the first folding frequency if the second folding frequency is smaller than the third folding frequency, and the first non-image folding frequency is equal to the first repeating frequency minus the first folding frequency if the second folding frequency is larger than the third folding frequency; the assumed parameter generating module is used for assuming that the first folding order is equal to the second folding order or equal to the second folding order plus one, assuming that the second non-mirror folding frequency is equal to the second folding frequency or equal to the second repeating frequency minus the first folding frequency, and obtaining four groups of assumed parameters; The system comprises an equation set generating module, a total of four equation sets and a total of four equation sets, wherein the equation set generating module is used for utilizing each set of hypothesis parameters, and for a first path Talbot frequency-time mapping module and a second path Talbot frequency-time mapping module, the sum of the product of a folding order and a repetition frequency is equal to the real frequency without mirror image; The equation set solving module is used for solving four equation sets to obtain four sets of solutions, wherein each set of solutions comprises a first folding order, a first non-mirror image folding frequency, a second folding order and a second non-mirror image folding frequency; And the real frequency recovery module is used for selecting a solution with the first folding order and the second folding order being non-negative integers from the four groups of solutions as a real solution, and calculating the real frequency by using the real solution.
8. A computer readable storage medium having stored thereon a computer program, characterized in that the computer program, when executed by a processor, implements the wideband signal real-time spectrum analysis method of claim 5.

Description

Broadband signal real-time spectrum analysis system, method, device and storage medium Technical Field The application relates to the technical field of microwave photonics and photoelectric detection, and more particularly to a broadband signal real-time spectrum analysis system, method, apparatus and storage medium. Background With the development of radar detection, electronic countermeasure and broadband communication technologies, the instantaneous bandwidth of the radio frequency signal to be detected is continuously improved, and the frequency range can cover tens of GHz or even higher. The traditional pure electric scheme is limited by the sampling rate and the bandwidth of the analog-to-digital converter, and is difficult to achieve the combination of large bandwidth, high resolution and real-time performance. Microwave photonics utilizes the high-broadband and low-loss characteristics of an optical carrier wave, can complete high-speed signal processing and spectrum analysis in an optical domain, and becomes an important way for realizing broadband frequency measurement. According to a Talbot effect-based Frequency-time mapping (Talbot-based Frequency-to-TIME MAPPING) scheme, the spectrum information of a radio Frequency signal can be mapped into a time waveform of light intensity by carrying out dispersion broadening and Talbot shaping on a periodic light pulse sequence, and then the spectrum analysis and the Frequency measurement can be realized through photoelectric detection and sampling. The system has compact structure, is easy to realize high resolution and high dynamic range, and is one of hot spots studied in recent years. However, existing Talbot spectral analysis and Talbot frequency measurement schemes commonly employ a single pulse repetition frequency, the effective aliasing-free measurement bandwidth of which is typically limited to about half the pulse repetition frequency. When the frequency of the radio frequency signal to be detected exceeds the Nyquist bandwidth, the high frequency component is folded back to the baseband, so that different real frequencies correspond to the same time position or alias frequency, and frequency aliasing and folding ambiguity are generated. Especially under the radio frequency signal to be detected or a multi-target scene, the real position of each frequency component is difficult to be uniquely determined only through single-path Talbot output, the existing scheme is often effective only for single-frequency or narrow-band signals, and the wide-band and multi-source unambiguous frequency measurement is difficult to realize. On the other hand, the multi-optical comb and multi-recovery frequency downsampling scheme proposed in the prior literature can recover the real frequency by utilizing a plurality of groups of beat frequencies generated by a plurality of different repetition frequencies through methods of integer property, solution space division, remainder matching and the like, and expands the unambiguous measurement range. However, the scheme usually depends on a multi-optical comb or a complex optical down-conversion structure, has higher realization difficulty, is used for processing beat signals in multiple directions, and is not combined with Talbot frequency-time mapping. Therefore, a new Talbot frequency measurement scheme is needed in the prior art, the concept of multi-sampling rate and aliasing is introduced while the system structure is kept relatively simple, the problem of frequency aliasing and folding ambiguity of a single-sampling rate Talbot system under high frequency and multi-frequency conditions is solved, and broadband, unambiguous and multi-source frequency measurement is realized. Disclosure of Invention In view of the above drawbacks of the prior art, the present application aims to provide a system, a method, a device and a storage medium for real-time spectrum analysis of a wideband signal, which are used for solving the problems of frequency aliasing and folding ambiguity of a single sampling rate Talbot system under high frequency and multiple frequency conditions, and realizing wideband, unambiguous and multi-source frequency measurement. In a first aspect, the present application provides a real-time spectrum analysis system for a broadband signal, the broadband signal including a radio frequency signal to be detected, the real-time spectrum analysis system comprising: The Talbot frequency-time mapping module comprises a pulse light source, an electro-optical modulator, a dispersion element and a photoelectric detector which are sequentially connected, wherein the Talbot frequency-time mapping module is used for converting a radio frequency signal to be detected into an electric signal, and the delay time of the electric signal corresponds to the frequency of the radio frequency signal to be detected; the digital signal processing module is used for converting the delay time of the electric signal into folding