Transient response measurement system and method for electro-optic intensity modulator

Abstract

The invention belongs to the technical field of photoelectric measurement, particularly relates to a transient response measurement system and method of an electro-optical intensity modulator, and aims to solve the problem that high-precision and ultra-wideband measurement cannot be realized due to limitation of a measurement instrument in the conventional measurement means. The system comprises a signal generation module and a response measurement module. The signal generation module is used for generating sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and respectively inputting the sampling light and the standard pulse signal into the electro-optical intensity modulator to be measured; wherein the electro-optical intensity modulator to be measured outputs an optical signal after frequency reduction sampling; and the response measurement module is used for acquiring an electric signal based on the optical signal after underclocking sampling, performing acquisition and underclocking sampling reduction processing on the electric signal based on the asynchronous sampling trigger signal, and removing a standard pulse signal waveform through deconvolution calculation to obtain a transient response of the electro-optical intensity modulator to be measured. According to the invention, ultra-wideband measurement can be realized.

Description

Background Art

[0002] In recent years, microwave photonic links have broad application prospects in the fields of wireless communication, intelligent communication, radar, etc. They are mainly used to realize the mutual conversion and transmission of microwaves and light waves, overcoming the defects of high-speed electronic devices such as large losses and complex systems. Electro-optic intensity modulators are the core optoelectronic devices in microwave photonic links. With the development of science and technology, the attention paid to the waveform information of broadband signals in microwave photonic links is increasing, and higher requirements are also put forward for key technical indicators such as the transient response of electro-optic modulators. Transient response reveals important characteristics of device materials, systems and functions, and directly affects the overall performance indicators of microwave photonic links. Therefore, accurate measurement of transient response has become an important prerequisite for the development of microwave photonic technology.

[0003] Common measurement methods include spectral analysis and electrical spectral analysis. Due to the low measurement resolution and dynamic range of the spectrometer, the measurement accuracy of spectral analysis is low. Electrical spectral analysis can achieve high-precision measurement, but testing in an ultra-wide frequency range requires ultra-high-speed measuring instruments. Therefore, the realization of ultra-wideband measurement is limited by the development level of the measuring instruments. Summary of the invention

[0004] In order to solve the above-mentioned problem in the prior art, that is, the problem that the existing measurement means cannot achieve high-precision, ultra-wideband measurement due to the limitation of the measuring instruments, the present invention provides an electro-optic intensity modulator transient response measurement system and method, which downsamples the input high-speed pulse signal based on the asynchronous sampling principle, and realizes the measurement of the transient response of the electro-optic intensity modulator through deconvolution calculation.

[0005] In one aspect of the present invention, a system for measuring transient response of an electro-optical intensity modulator is provided, comprising a signal generating module and a response measuring module; wherein the signal generating module is connected to the input end of the electro-optical intensity modulator to be measured, and the response measuring module is connected to the output end of the electro-optical intensity modulator to be measured;

[0006] The signal generating module is used to generate sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and input the sampling light and the standard pulse signal into the electro-optical intensity modulator to be tested respectively, and input the asynchronous sampling trigger signal into the response measuring module at the same time; wherein the electro-optical intensity modulator to be tested performs asynchronous sampling on the sampling light after being modulated by the standard pulse signal, and outputs a down-sampled optical signal;

[0007] The response measurement module is used to obtain an electrical signal based on the optical signal after the down-sampling, collect the electrical signal based on the asynchronous sampling trigger signal, perform down-sampling restoration processing on the electrical signal, and remove the standard pulse signal waveform through deconvolution calculation to obtain the transient response of the electro-optical intensity modulator to be tested. Preferably, the signal generation module includes a femtosecond dual optical comb generation module, a difference frequency locking module and a pulse generation module;

[0008] The femtosecond dual-comb generating module is used to generate dual-path laser pulses, wherein the first path of laser pulses is loaded into the pulse generating module as the excitation light, and the second path of laser pulses is input into the electro-optical intensity modulator to be measured as the sampling light;

[0009] The difference frequency locking module is used to lock the repetition frequency difference so that the dual-path laser pulses generate a preset repetition frequency difference, and output the asynchronous sampling trigger signal according to the preset repetition frequency difference;

[0010] The pulse generating module is used to generate a standard pulse signal based on the first laser pulse and input it into the electro-optic intensity modulator to be tested.

[0011] Preferably, the system further comprises a bias point control module connected to a DC input port of the electro-optic intensity modulator to be tested;

[0012] The bias point control module is used to input a DC voltage into a DC input port of the electro-optic intensity modulator to be tested and set a voltage value to control the electro-optic intensity modulator to be tested to be at an optimal working bias point.

[0013] Preferably, the dual-path laser pulses generated by the femtosecond dual-comb generating module are femtosecond pulses with a width less than 200 femtoseconds, and the repetition frequency of the dual-path laser pulses is 100 MHz.

[0014] Preferably, the locking frequency difference of the difference frequency locking module is 100 Hz or 1 kHz.

[0015] Preferably, the pulse generating module is a broadband photodetector, and the bandwidth of the standard pulse signal generated by the pulse generating module is larger than the working bandwidth of the electro-optic intensity modulator to be tested.

[0016] Preferably, the response measurement module includes a photoelectric detector and a signal acquisition and processing module; wherein the signal acquisition and processing module includes a signal acquisition and restoration module and a signal waveform shaping module;

[0017] The photoelectric detector is used to perform photoelectric conversion on the down-sampled optical signal to obtain the electrical signal;

[0018] The signal acquisition and restoration module is used to acquire the electrical signal and perform down-frequency sampling and restoration processing based on the asynchronous sampling trigger signal;

[0019] The signal waveform shaping module is used to obtain the transient response of the electro-optical intensity modulator to be tested by removing the standard pulse signal waveform through deconvolution calculation.

[0020] Another aspect of the present invention provides a method for measuring transient response of an electro-optical intensity modulator, comprising:

[0021] Generate sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and input the sampling light and the standard pulse signal into the electro-optical intensity modulator to be tested respectively; wherein the electro-optical intensity modulator to be tested performs asynchronous sampling on the sampling light after being modulated by the standard pulse signal, and outputs a down-sampled optical signal;

[0022] After obtaining an electrical signal based on the down-sampled optical signal, the electrical signal is collected and down-sampled based on the asynchronous sampling trigger signal, and the standard pulse signal waveform is removed by deconvolution calculation to obtain the transient response of the electro-optical intensity modulator to be tested.

[0023] Preferably, generating sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and inputting the sampling light and the standard pulse signal into the electro-optical intensity modulator to be measured respectively comprises:

[0024] Generate dual-path laser pulses, wherein a first path of laser pulses is loaded into the pulse generation module as excitation light, and a second path of laser pulses is input into the electro-optical intensity modulator to be measured as sampling light;

[0025] The dual-path laser pulses generate a preset repetition frequency difference by locking the repetition frequency difference, and output the asynchronous sampling trigger signal according to the preset repetition frequency difference;

[0026] A standard pulse signal is generated based on the first laser pulse and input into the electro-optical intensity modulator to be tested.

[0027] Preferably, the method further comprises: inputting a DC voltage into a DC input port of the electro-optical intensity modulator to be tested and setting a voltage value to control the electro-optical intensity modulator to be tested to be at an optimal operating bias point.

[0028] Beneficial effects of the present invention:

[0029] (1) Based on the asynchronous sampling principle, the optical signal modulated by the standard pulse signal is downsampled, which has a faster sampling time;

[0030] (2) The repetition frequency difference between the two paths of light is generally in the Hertz or kilohertz range, thus having the characteristic of high resolution;

[0031] (3) The ability to achieve ultra-wideband measurements without being limited by the bandwidth of the measuring instrument enables accurate measurement of the transient response of high-performance electro-optic intensity modulators. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0033] Figure 1 It is a structural block diagram of a transient response measurement system of an electro-optic intensity modulator;

[0034] Figure 2 It is the structural block diagram of the signal generation module;

[0035] Figure 3 It is a schematic diagram of the physical device connection of the electro-optic intensity modulator transient response measurement system;

[0036] Figure 4 It is a connection diagram of another embodiment of a physical device of an electro-optic intensity modulator transient response measurement system;

[0037] Figure 5 It is the structural block diagram of the response measurement module;

[0038] Figure 6 This is the schematic diagram of asynchronous sampling achieved by femtosecond dual optical comb;

[0039] Figure 7 The present invention is a flow chart of a method for measuring transient response of an electro-optic intensity modulator. DETAILED DESCRIPTION

[0040] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the relevant invention are shown in the accompanying drawings.

[0041] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0042] The present invention provides an electro-optic intensity modulator transient response measurement system. The system performs frequency down sampling on an input high-speed pulse signal based on the asynchronous sampling principle, and realizes measurement of the electro-optic intensity modulator transient response through deconvolution calculation, thereby solving the problem that the existing measurement means cannot realize high-precision and ultra-wideband measurement due to the limitation of the measuring instrument.

[0043] The present invention provides an electro-optical intensity modulator transient response measurement system, comprising a signal generating module and a response measuring module; wherein the signal generating module is connected to the input end of the electro-optical intensity modulator to be measured, and the response measuring module is connected to the output end of the electro-optical intensity modulator to be measured;

[0044] The signal generating module is used to generate sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and input the sampling light and the standard pulse signal into the electro-optical intensity modulator to be tested respectively, and input the asynchronous sampling trigger signal into the response measuring module at the same time; wherein the electro-optical intensity modulator to be tested performs asynchronous sampling on the sampling light after being modulated by the standard pulse signal, and outputs a down-sampled optical signal;

[0045] The response measurement module is used to obtain an electrical signal based on the optical signal after the down-convolution sampling, collect the electrical signal based on the asynchronous sampling trigger signal, perform down-convolution sampling and restoration processing on the electrical signal, and obtain the transient response of the electro-optical intensity modulator to be tested by removing the standard pulse signal waveform through deconvolution calculation.

[0046] In order to more clearly explain the transient response measurement system of the electro-optic intensity modulator of the present invention, the following is combined with Figure 1 Each module in the embodiment of the present invention is described in detail.

[0047] The electro-optical intensity modulator transient response measurement system of the first embodiment of the present invention comprises a signal generating module 101 and a response measuring module 102; wherein the signal generating module 101 is connected to the input end of the electro-optical intensity modulator 103 to be measured, and the response measuring module 102 is connected to the output end of the electro-optical intensity modulator 103 to be measured;

[0048] Specifically, the input end of the electro-optical intensity modulator 103 to be tested includes an optical input port, a radio frequency signal input port and a direct current input port.

[0049] The signal generating module 101 is used to generate sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and input the sampling light and the standard pulse signal into the electro-optical intensity modulator 103 to be tested respectively, and input the asynchronous sampling trigger signal into the response measuring module 102 at the same time; wherein the electro-optical intensity modulator 103 to be tested performs asynchronous sampling on the sampling light after being modulated by the standard pulse signal, and outputs the optical signal after the down-conversion sampling;

[0050] The response measurement module 102 is used to obtain an electrical signal based on the optical signal after the down-sampling, collect the electrical signal based on the asynchronous sampling trigger signal, perform down-sampling restoration processing on the electrical signal, and obtain the transient response of the electro-optical intensity modulator 103 to be tested by removing the standard pulse signal waveform through deconvolution calculation.

[0051] The present invention performs frequency down sampling on the input high-speed pulse signal based on the asynchronous sampling principle, and realizes the measurement of the transient response of the electro-optical intensity modulator through deconvolution calculation, thereby solving the problem that the existing measurement means cannot realize high-precision and ultra-wideband measurement due to the limitation of the measuring instrument.

[0052] It should be noted that the electro-optical intensity modulator transient response measurement system provided in the above embodiment is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the modules or steps in the embodiments of the present invention can be decomposed or combined. For example, the modules in the above embodiment can be combined into one module, or further divided into multiple sub-modules to complete all or part of the functions described above. The names of the modules and steps involved in the embodiments of the present invention are only for distinguishing the modules or steps, and are not regarded as improper limitations of the present invention.

[0053] Based on the above embodiments, Figure 2 Said signal generating module comprises a femtosecond dual optical comb generating module 201, a difference frequency locking module 202 and a pulse generating module 203;

[0054] Here, if Figure 3 As shown, the physical device of the electro-optic intensity modulator transient response measurement system includes a femtosecond dual-comb generating module 1, a difference frequency locking module 2, an ultrafast pulse generating module 3, an electro-optic intensity modulator 4, a photodetector 5 and a signal acquisition and processing module 6.

[0055] The femtosecond dual-comb generating module 201 is used to generate dual-path laser pulses, wherein the first path of laser pulses is loaded into the pulse generating module 203 as the excitation light, and the second path of laser pulses is input into the electro-optical intensity modulator to be measured as the sampling light;

[0056] Specifically, if Figure 2 Combined with Figure 3 The femtosecond dual-comb generating module 1 outputs two laser beams: a first light beam and a second light beam, that is, a first laser pulse and a second laser pulse.

[0057] like Figure 3 The first light is input to the pulse generation module 3 to generate a repetition frequency of f r The standard pulse signal is loaded into the RF signal input port of the electro-optical intensity modulator 4 to be tested, and the second light is input into the optical input port of the electro-optical intensity modulator 4 to be tested as the sampling light, and the optical signal modulated by the standard pulse signal is asynchronously sampled.

[0058] The difference frequency locking module 202 is used to lock the repetition frequency difference so that the dual-path laser pulses generate a preset repetition frequency difference, and output the asynchronous sampling trigger signal according to the preset repetition frequency difference;

[0059] Specifically, if Figure 2 Combined with Figure 3 , the difference frequency locking module 2 locks the repetition frequency of the first light to f r , the repetition frequency of the second light is f r -Δf, and at the same time output a square wave signal with a repetition frequency of Δf as an asynchronous sampling trigger signal to the signal acquisition processing module 5 to provide the trigger signal required for asynchronous sampling.

[0060] The pulse generating module 203 is used to generate a standard pulse signal based on the first laser pulse and input it into the electro-optic intensity modulator to be tested.

[0061] Specifically, combined Figure 3 , the 4 pairs of electro-optical intensity modulators to be tested generate optical signals after being modulated by the standard pulse signal.

[0062] Based on the above embodiments, combined with Figure 2 , the measurement system further comprises a bias point control module 204 connected to a DC input port of the electro-optic intensity modulator to be measured;

[0063] The bias point control module 204 is used to input a DC voltage into a DC input port of the electro-optic intensity modulator to be tested and set a voltage value to control the electro-optic intensity modulator to be tested to be at an optimal working bias point.

[0064] That is to say, combined Figure 4 , using the bias point control module 7, outputting a DC voltage to the DC input port of the electro-optic intensity modulator to be tested, setting a suitable and fixed voltage value to maximize the modulation depth of the electrical signal modulated by the standard pulse signal and maintain the stability of the working state of the electro-optic intensity modulator to be tested.

[0065] Based on the above embodiment, the dual-path laser pulses generated by the femtosecond dual-comb generating module are femtosecond pulses with a width less than 200 femtoseconds, and the repetition frequency of the dual-path laser pulses is 100 MHz.

[0066] Based on the above embodiment, the locking frequency difference of the difference frequency locking module is 100 Hz or 1 kHz.

[0067] Based on the above embodiment, the pulse generating module is a broadband photoelectric detector, and the bandwidth of the standard pulse signal generated by the pulse generating module is larger than the working bandwidth of the electro-optic intensity modulator to be tested.

[0068] Specifically, the pulse generation module selects a broadband photodetector with a 110 GHz and 1 mm coaxial connection, and generates a standard pulse signal with a bandwidth of 110 GHz and a width of about 3 ps under the excitation of the 200 femtosecond laser pulse.

[0069] The bandwidth of the standard pulse signal generated by the pulse generating module is greater than the working bandwidth of the electro-optical intensity modulator to be tested, and the larger the bandwidth of the standard pulse signal is, the larger the transient response test frequency range is.

[0070] Based on the above embodiments, Figure 5 As shown, the response measurement module includes a photoelectric detector 501 and a signal acquisition and processing module 502; wherein, the signal acquisition and processing module 502 includes a signal acquisition and restoration module 5021 and a signal waveform shaping module 5022;

[0071] The photodetector 501 is used to perform photoelectric conversion on the down-sampled optical signal to obtain the electrical signal;

[0072] The signal acquisition and restoration module 5021 is used to acquire the electrical signal and perform down-frequency sampling and restoration processing based on the asynchronous sampling trigger signal;

[0073] Specifically, if Figure 6 The schematic diagram of asynchronous sampling of the femtosecond dual optical comb is shown in the figure. When the repetition frequency of the standard pulse generated by the first optical excitation is f r The time difference between the two optical pulses changes linearly in the continuous cycle, which is equivalent to the scanning rate of Δf in the whole 1 / f. r Scan in the time window to obtain the waveform after downsampling. r By restoring the multiple relationship of Δf to the signal before frequency reduction, the actual electro-optical signal waveform modulated by the standard pulse signal at the output end of the electro-optical intensity modulator can be obtained.

[0074] The signal waveform shaping module 5022 is used to obtain the transient response of the electro-optic intensity modulator to be tested by removing the standard pulse signal waveform through deconvolution calculation.

[0075] It should be noted that the standard pulse signal waveform is p1, and the result obtained after the signal acquisition and processing module collects and restores it is p2. The above process can be expressed as p2=p1*hEOM, where hEOM is the transient response of the electro-optic intensity modulator to be tested. The transient response waveform of the electro-optic intensity modulator to be tested can be obtained by removing the standard pulse signal waveform through deconvolution calculation, and the transient response characteristic waveform parameters can be extracted from it.

[0076] The method for measuring transient response of an electro-optical intensity modulator according to the second embodiment of the present invention comprises steps S701 and S702. Figure 7 As shown, each step is described in detail as follows:

[0077] Step S701, generating sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and inputting the sampling light and the standard pulse signal into the electro-optical intensity modulator to be tested respectively; wherein the electro-optical intensity modulator to be tested performs asynchronous sampling on the sampling light after being modulated by the standard pulse signal, and outputs a down-sampled optical signal;

[0078] Step S702, after obtaining an electrical signal based on the down-sampled optical signal, the electrical signal is collected and down-sampled based on the asynchronous sampling trigger signal, and the standard pulse signal waveform is removed by deconvolution calculation to obtain the transient response of the electro-optical intensity modulator to be tested.

[0079] The present invention adopts an optical domain measurement method to achieve high-resolution characteristics consistent with an electrical domain test method, and can achieve ultra-wideband measurement capabilities without the need for ultra-wideband measurement instruments, which is conducive to accurate measurement of transient responses of high-performance electro-optic intensity modulators.

[0080] Based on the above embodiment, generating sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and inputting the sampling light and the standard pulse signal into the electro-optical intensity modulator to be tested respectively comprises:

[0081] Generate dual-path laser pulses, wherein a first path of laser pulses is loaded into the pulse generation module as excitation light, and a second path of laser pulses is input into the electro-optical intensity modulator to be measured as sampling light;

[0082] The dual-path laser pulses generate a preset repetition frequency difference by locking the repetition frequency difference, and output the asynchronous sampling trigger signal according to the preset repetition frequency difference;

[0083] A standard pulse signal is generated based on the first laser pulse and input into the electro-optical intensity modulator to be tested.

[0084] Based on the above embodiment, the method further includes: inputting a DC voltage into a DC input port of the electro-optical intensity modulator to be tested and setting a voltage value to control the electro-optical intensity modulator to be tested to be at an optimal working bias point.

[0085] Although the various steps in the above embodiment are described in the above-mentioned order, those skilled in the art can understand that in order to achieve the effect of this embodiment, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in a reverse order. These simple changes are within the scope of protection of the present invention.

[0086] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process and related instructions of the method described above can refer to the corresponding process in the aforementioned system embodiment, and will not be repeated here.

[0087] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0088] The terms "first", "second", etc. are used to distinguish similar objects rather than to describe or indicate a particular order or sequence.

[0089] The term "comprise" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus / device.

[0090] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. An electro-optic intensity modulator transient response measurement system, characterized in that: It includes a signal generating module and a response measuring module; wherein the signal generating module is connected to the input end of the electro-optical intensity modulator to be tested, and the response measuring module is connected to the output end of the electro-optical intensity modulator to be tested; The signal generating module is used to generate sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and input the sampling light and the standard pulse signal into the electro-optical intensity modulator to be tested respectively, and input the asynchronous sampling trigger signal into the response measuring module at the same time; wherein the electro-optical intensity modulator to be tested performs asynchronous sampling on the sampling light after being modulated by the standard pulse signal, and outputs a down-sampled optical signal; The response measurement module is used to obtain an electrical signal based on the optical signal after the down-convolution sampling, collect the electrical signal based on the asynchronous sampling trigger signal, perform down-convolution sampling and restoration processing on the electrical signal, and obtain the transient response of the electro-optical intensity modulator to be tested by removing the standard pulse signal waveform through deconvolution calculation.

2. The electro-optic intensity modulator transient response measurement system according to claim 1, characterized in that: The signal generation module includes a femtosecond dual-comb generation module, a difference frequency locking module and a pulse generation module; The femtosecond dual-comb generating module is used to generate dual-path laser pulses, wherein the first path of laser pulses is loaded into the pulse generating module as the excitation light, and the second path of laser pulses is input into the electro-optical intensity modulator to be measured as the sampling light; The difference frequency locking module is used to lock the repetition frequency difference so that the dual-path laser pulses generate a preset repetition frequency difference, and output the asynchronous sampling trigger signal according to the preset repetition frequency difference; The pulse generating module is used to generate a standard pulse signal based on the first laser pulse and input it into the electro-optic intensity modulator to be tested.

3. The electro-optic intensity modulator transient response measurement system according to claim 2, characterized in that: Also included is a bias point control module connected to the DC input port of the electro-optic intensity modulator to be tested; The bias point control module is used to input a DC voltage into a DC input port of the electro-optic intensity modulator to be tested and set a voltage value to control the electro-optic intensity modulator to be tested to be at an optimal working bias point.

4. The electro-optic intensity modulator transient response measurement system according to claim 2, characterized in that: The dual-path laser pulses generated by the femtosecond dual-comb generation module are femtosecond pulses with a width less than 200 femtoseconds, and the repetition frequency of the dual-path laser pulses is 100 MHz.

5. The electro-optic intensity modulator transient response measurement system according to claim 2, characterized in that: The locking frequency difference of the difference frequency locking module is 100 Hz or 1 kHz.

6. The electro-optic intensity modulator transient response measurement system according to claim 2, characterized in that: The pulse generating module is a broadband photoelectric detector, and the bandwidth of the standard pulse signal generated by the pulse generating module is larger than the working bandwidth of the electro-optic intensity modulator to be tested.

7. The electro-optic intensity modulator transient response measurement system according to claim 1, characterized in that: The response measurement module includes a photoelectric detector and a signal acquisition and processing module; wherein the signal acquisition and processing module includes a signal acquisition and restoration module and a signal waveform shaping module; The photoelectric detector is used to perform photoelectric conversion on the down-sampled optical signal to obtain the electrical signal; The signal acquisition and restoration module is used to acquire the electrical signal and perform down-frequency sampling and restoration processing based on the asynchronous sampling trigger signal; The signal waveform shaping module is used to obtain the transient response of the electro-optical intensity modulator to be tested by removing the standard pulse signal waveform through deconvolution calculation.

8. A method for measuring transient response of an electro-optic intensity modulator, characterized in that: include: Generate sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and input the sampling light and the standard pulse signal into the electro-optical intensity modulator to be tested respectively; wherein the electro-optical intensity modulator to be tested performs asynchronous sampling on the sampling light after being modulated by the standard pulse signal, and outputs a down-sampled optical signal; After obtaining an electrical signal based on the down-sampled optical signal, the electrical signal is collected and down-sampled based on the asynchronous sampling trigger signal, and the standard pulse signal waveform is removed by deconvolution calculation to obtain the transient response of the electro-optical intensity modulator to be tested.

9. The method for measuring transient response of an electro-optical intensity modulator according to claim 8, characterized in that: Generating sampling light, a standard pulse signal and an asynchronous sampling trigger signal, and inputting the sampling light and the standard pulse signal into the electro-optical intensity modulator to be tested respectively comprises: Generate dual-path laser pulses, wherein a first path of laser pulses is loaded into the pulse generation module as excitation light, and a second path of laser pulses is input into the electro-optical intensity modulator to be measured as sampling light; The dual-path laser pulses generate a preset repetition frequency difference by locking the repetition frequency difference, and output the asynchronous sampling trigger signal according to the preset repetition frequency difference; A standard pulse signal is generated based on the first laser pulse and input into the electro-optical intensity modulator to be tested.

10. The method for measuring transient response of an electro-optical intensity modulator according to claim 8, characterized in that: The method further comprises: inputting a DC voltage into a DC input port of the electro-optical intensity modulator to be tested and setting a voltage value to control the electro-optical intensity modulator to be tested to be at an optimal working bias point.

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