A system and method for photon assisted microwave signal time-frequency-amplitude-phase measurement

Abstract

The application discloses a kind of photonic auxiliary microwave signal time-frequency amplitude phase measurement system and method, pulse light source output light pulse in the system enters input end dispersion medium and completes pulse broadening, then enters electro-optic modulation module, simultaneously power divider receives microwave signal and it is divided two-way input electro-optic modulation module in upper and lower sub-modulator to modulate light pulse;The modulated light signal output by the electro-optic modulation module passes through output end dispersion medium, completes time convolution process, after this, output light signal will pass through optical coupling module and be divided into two paths, in turn pass through polarization controller, polarization beam splitter, photodetector, analog-digital converter, digital signal processor, the position information and amplitude information of electric pulse are collected, and the time, amplitude, frequency and phase information of microwave signal are obtained.The application can simultaneously measure the time, frequency, amplitude, phase information of microwave signal, and does not need complex post-processing, and processing speed is fast.

Description

Technical Field

[0001] This invention belongs to the field of microwave photonic signal processing technology, specifically relating to a photonic-assisted microwave signal time-frequency amplitude-phase measurement system and method. Background Technology

[0002] Real-time measurement of multidimensional parameters of microwave signals is extremely important in signal analysis, electronic countermeasures, and instrumentation, attracting widespread attention from researchers. Firstly, the frequency of a microwave signal is fundamental for signal identification, helping systems accurately analyze signal characteristics and achieve effective signal separation and filtering in back-end processing. Furthermore, in practical applications, the microwave signals under test are often burst pulse signals. Identifying the pulse amplitude (PA), pulse width (PW), time of arrival (TOA) (which can also be characterized as the pulse repetition period), and modulation format of such signals can help systems estimate target distance, roughly identify target types, and predict the arrival time of the next target.

[0003] However, traditional electronic methods face several challenges, such as limited instantaneous frequency measurement bandwidth, susceptibility to electromagnetic interference, and non-real-time detection. Photon-assisted microwave signal parameter measurement methods have attracted widespread attention from researchers due to their large bandwidth, low loss, and resistance to electromagnetic interference.

[0004] Numerous schemes have been proposed for photon-assisted microwave signal frequency measurement. Microwave photon channelization enables high-resolution and high-sensitivity frequency measurement in each channel. Photon time stretching compresses bandwidth by stretching the microwave signal envelope, reducing the load on the output analog-to-digital converter. Photon-assisted compressed sensing utilizes signal sparsity to achieve low-sampling-rate signal acquisition, reducing the system's requirements for data storage and transmission. However, channelization schemes suffer from large system size and high loss, while the latter two frequency measurement schemes face complex back-end processing issues, leading to processing delays and limiting their application scope. To achieve real-time frequency measurement while reducing system complexity, instantaneous frequency measurement is commonly used. This scheme utilizes dispersion fading, optical filters with special spectral responses, and polarization multiplexing to construct amplitude comparison curves during the frequency-to-amplitude mapping process. Because the microwave signal frequency can be directly obtained from the amplitude comparison curve without further processing by the analog-to-digital converter, instantaneous frequency measurement offers high real-time performance, large operating bandwidth, and ease of integration. However, the drawback of instantaneous frequency measurement schemes is the inability to simultaneously measure multiple signal frequencies, which poses a significant challenge to their application in complex electromagnetic environments. Real-time Fourier transform (RTF), based on frequency-to-time mapping, can achieve simultaneous detection of multiple carrier frequency signals while ensuring real-time measurement. For spectral analysis of radio frequency signals, RTF based on the Thaler effect has the advantage of high repetition rate, enabling the capture of short-time jump signals and achieving gapless frequency measurement of microwave signals. However, this scheme has a relatively small frequency measurement bandwidth. Real-time Fourier transform based on time lenses uses quadratic phase modulation to generate chirped light. The microwave signal is modulated onto this chirped light and then passes through a matched dispersive medium to complete the frequency-to-time mapping. However, the optimal performance of time lenses is limited by the electronic devices that generate the quadratic phase modulation signal. Real-time Fourier transform based on time convolution can achieve a larger frequency measurement bandwidth. This scheme uses two dispersive media with complementary dispersion. The first dispersive medium is used to broaden the input light pulse to generate chirped light, and the second dispersive medium is used to compress the light pulse to complete the frequency-to-time mapping. The final output time-domain signal can be regarded as the result of the frequency-domain convolution of the input light pulse and the microwave signal.

[0005] To comprehensively analyze microwave signal parameters, after frequency measurement, it is necessary to detect PA, PW, and TOA, as well as identify the intra-pulse modulation format, laying the foundation for subsequent detailed analysis. However, existing real-time Fourier transform methods are limited to frequency identification of microwave signals and cannot distinguish the phase information and modulation format of microwave signals. Therefore, improvements are needed to address these technical issues. Summary of the Invention

[0006] In view of the above-mentioned deficiencies in the existing technology, the present invention provides a photon-assisted microwave signal time-frequency amplitude-phase measurement system and method.

[0007] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0008] A photon-assisted microwave signal time-frequency amplitude-phase measurement system includes a pulsed light source, an input dispersive medium, an electro-optic modulation module, a power divider, a delay module, an output dispersive medium, an optical coupling module, a polarization controller, a polarization beam splitter, a photodetector, an analog-to-digital converter, and a digital signal processor.

[0009] The pulsed light source outputs a light pulse that enters the dispersive medium at the input end to complete pulse broadening, and then enters the electro-optic modulation module. Simultaneously, a power divider receives the microwave signal under test and splits it into two paths, inputting them into the upper and lower sub-modulators of the electro-optic modulation module to modulate the light pulse. The modulated light signal output from the electro-optic modulation module passes through the dispersive medium at the output end to complete a time convolution process. Afterward, the output light signal is split into two paths by an optical coupling module, and then sequentially passes through a polarization controller, a polarization beam splitter, a photodetector, an analog-to-digital converter, and a digital signal processor to collect the position and amplitude information of the electrical pulse, thus obtaining the time, amplitude, frequency, and phase information of the microwave signal. As a preferred embodiment, the power divider receives the microwave signal under test and splits it into two paths, inputting them into the upper and lower sub-modulators of the electro-optic modulation module. Before the microwave signal is input to the lower sub-modulator, a time delay is introduced by a delay module. After modulation by the lower sub-modulator, the signal undergoes a 90° polarization rotation to complete the polarization state rotation.

[0010] As a preferred embodiment, the output optical signal is split into two paths by an optical coupling module, and then sequentially passes through a polarization controller, a polarization beam splitter, a photodetector, an analog-to-digital converter, and a digital signal processor. The acquisition of the position and amplitude information of the electrical pulse is specifically implemented as follows: one path passes through the first polarization controller and enters the first polarization beam splitter at a 0° principal axis angle, obtaining a signal of one polarization state, which enters the first photodetector, causing the optical pulse to be converted into an electrical pulse. Then, the first analog-to-digital converter acquires the position and amplitude information of the electrical pulse, transmits it to the digital signal processor, and calculates the frequency and amplitude of the microwave signal.

[0011] Another path passes through the second polarization controller and enters the second polarization beam splitter at a 45° principal axis angle. It is then split into two signals, which enter the second photodetector and the third photodetector, respectively. The second analog-to-digital converter and the third analog-to-digital converter collect the electrical pulse information output by the second photodetector and the third photodetector, respectively, and transmit it to the digital signal processor. The processor calculates the amplitude information corresponding to the time of the two output signals and performs specific calculations to integrate them, thereby obtaining the phase information of the microwave signal under test.

[0012] As a preferred embodiment, the input dispersion medium is either a single-mode fiber or a chirped fiber grating, and the output dispersion medium is either a dispersion-compensating fiber or a chirped fiber grating.

[0013] As a preferred embodiment, the electro-optic modulation module is a polarization multiplexed Mach-Zehnder modulator, whose output optical signal consists of two polarization-orthogonal signals.

[0014] Another objective of this invention is to provide a method for implementing a photon-assisted microwave signal time-frequency amplitude-phase measurement system, the steps of which are as follows:

[0015] S1, The pulse light source outputs a pulse train, which passes through a dispersion measure of... After dispersion at the input end, the light pulse is broadened, and the broadened light pulse will be modulated by a microwave signal;

[0016] S2. Before modulation, the microwave signal is split into two and input to the upper and lower sub-modulators of the electro-optic modulator. One of the inputs is then... The time delay is used to perform carrier-suppressed double-sideband modulation on the optical pulses respectively;

[0017] S3, the polarization multiplexed signal output after modulation is subjected to a dispersion of... The output dispersion completes the frequency-to-time mapping of the microwave signal. After that, the polarization multiplexed signal is divided into upper and lower outputs, which are polarization controlled separately to complete the conversion from analog signal to digital signal.

[0018] S4. After the polarization state of the upper branch optical signal is adjusted, it enters the first polarization beam splitter at a principal axis angle of 0°, resulting in a signal with only one polarization state. This signal undergoes photoelectric conversion, analog-to-digital conversion, and finally back-end processing. The amplitude and frequency of the microwave signal are obtained based on the amplitude and time interval of the output pulse signal.

[0019] S5. After polarization state adjustment, the lower branch optical signal enters the second polarization beam splitter at a 45° principal axis angle for polarization beam splitting, resulting in two output signals that are either coherent or destructive. The two output optical signals then undergo photoelectric conversion. After analog-to-digital conversion, the two coherent or destructive signals are subtracted and added in the back-end processing to obtain the time-corresponding amplitude relationship of the output signals. Furthermore, the phase information of the input microwave signal can be deduced from the amplitude.

[0020] As a preferred option, each electrical pulse cycle after photoelectric conversion corresponds to one frequency-time mapping of the input microwave signal, and there are two electrical pulses in each cycle.

[0021] As a preferred option, if the microwave signal is a BPSK signal, then when the phase of the BPSK signal changes, the amplitude of the corresponding output signal will also change.

[0022] Compared with the prior art, the beneficial effects of this invention are:

[0023] (1) The present invention can simultaneously measure the time, frequency, amplitude and phase information of microwave signals.

[0024] (2) The present invention is based on real-time Fourier transform of time convolution, which does not require complex back-end processing and has a fast processing speed.

[0025] (3) The present invention is applicable to scenarios with multiple microwave signals and can simultaneously measure the time, frequency, amplitude and phase information of multiple microwave signals.

[0026] (4) The present invention is applicable to scenarios where the work is continuous and can measure the time, frequency, amplitude and phase information of microwave signals in real time without time gaps. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the photon-assisted microwave signal time-frequency amplitude-phase measurement system and method according to an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the real-time Fourier transform process based on temporal convolution according to an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram illustrating the principle of the BPSK signal modulation format identification process implemented by the photon-assisted microwave signal time-frequency amplitude-phase measurement system and method according to an embodiment of the present invention.

[0030] Figure 4 This is a time-domain diagram of the electrical signal output by the second photodetector.

[0031] Figure 5 This is a time-domain diagram of the electrical signal output by the third photodetector.

[0032] Figure 6 The output signal after calculation by the digital signal processor is represented by an amplitude information graph corresponding to time.

[0033] Figure 7 This is a time-domain plot of one of the mapping windows;

[0034] The components include: 1. Pulsed light source, 2. Input dispersive medium, 3a. Sub-modulator 1 of the electro-optic modulation module, 3b. Sub-modulator 2 of the electro-optic modulation module, 3c. 90° polarization rotator, 4. Power divider, 5. Delay module, 6. Output dispersive medium, 7. Optical coupling module, 8a. First polarization controller, 8b. Second polarization controller, 9a. First polarization beam splitter, 9b. Second polarization beam splitter, 10a. First photodetector, 10b. Second photodetector, 10c. Third photodetector, 11a. First analog-to-digital converter, 11b. Second analog-to-digital converter, 11c. Third analog-to-digital converter, 12. Digital signal processor. Detailed Implementation

[0035] To more clearly illustrate the embodiments of the present invention, specific implementation methods will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0036] Example:

[0037] like Figure 1 As shown, this embodiment proposes a photon-assisted microwave signal time-frequency amplitude-phase measurement system. It employs real-time Fourier transform technology based on time convolution and polarization-multiplexed pulse interferometry to achieve simultaneous measurement of the time, frequency, amplitude, and phase of multiple signals. The system includes: a pulsed light source 1, an input dispersion medium 2, an upper sub-modulator 3a and a lower sub-modulator 3b of the electro-optic modulation module, a 90° polarization rotator 3c, a power divider 4, a delay module 5, an output dispersion medium 6, an optical coupling module 7, a first polarization controller 8a, a second polarization controller 8b, a first polarization beam splitter 9a, a second polarization beam splitter 9b, a first photodetector 10a, a second photodetector 10b, a third photodetector 10c, a first analog-to-digital converter 11a, a second analog-to-digital converter 11b, a third analog-to-digital converter 11c, and a digital signal processor 12. Specifically, the electro-optic modulation module uses a polarization-multiplexed Mach-Zehnder modulator, the input dispersion medium 2 is a single-mode fiber, and the output dispersion medium 6 is a dispersion-compensating fiber.

[0038] A method for measuring the time, frequency, amplitude, and phase of a photon-assisted microwave signal includes the following steps:

[0039] The light pulse output from the pulsed light source 1 enters the input dispersion medium 2 to complete pulse broadening, and then enters the electro-optic modulation module. Simultaneously, the power divider 4 receives the microwave signal and splits it into two paths, inputting them into the upper 3a and lower 3b sub-modulators of the electro-optic modulation module to modulate the light pulse. Before the microwave signal enters the lower sub-modulator, a delay module 5 introduces a certain time delay. Furthermore, after modulation by the lower sub-modulator, the polarization state is rotated by the 90° polarization rotator 3c. The modulated light signal output from the electro-optic modulation module passes through the output dispersion medium 6 to complete the time convolution process. The output light signal is then split into two paths by the optical coupling module 7. One path passes through the first polarization controller 8a and the first polarization beam splitter 9a, and then enters the first photodetector 10a, converting the light pulse into an electrical pulse. The first analog-to-digital converter 11a collects the position and amplitude information of the electrical pulse and transmits it to the digital signal processor 12 to calculate the microwave signal frequency and amplitude. The other signal, after passing through the second polarization controller 8b and the second polarization beam splitter 9b, is split into two signals, which enter the second photodetector 10b and the third photodetector 10c respectively. The second analog-to-digital converter 11b and the third analog-to-digital converter 11c respectively collect the electrical pulse information output by the second photodetector 10b and the third photodetector 10c and transmit it to the digital signal processor 12. The amplitude information of the two signals corresponding to time is calculated, and the phase information of the microwave signal is deduced.

[0040] The working principle of the photon-assisted microwave signal time-frequency amplitude-phase measurement system and method provided by this invention is as follows:

[0041] Theoretically, the light pulse train output by a pulsed light source can be represented as

[0042] (1)

[0043] In the formula It is the period of the optical pulse train, which represents the system's interval. A frequency-time mapping is performed over time. The schematic diagram is shown below. Figure 2 The diagram at point A shows time t and the i-th light pulse. Assuming the light pulse is a Gaussian pulse, then... It is the full width at half maximum (FWHM) of the pulse, where A is the amplitude of the optical pulse. The optical pulse train passes through a dispersion value... The input dispersion completes pulse broadening, and its time-domain schematic diagram is shown below. Figure 2 The schematic diagram at point B is shown. The expression for the broadened pulse is:

[0044] (2)

[0045] First, the microwave signal under test is input into the upper and lower sub-modulators of a polarization-multiplexed Mach-Zehnder modulator via two channels. In our system, one channel introduces... The time delay causes a phase difference between the two channels. , It is the angular frequency of the microwave signal. Therefore, the signals entering the modulator can be written as follows: , , It is the amplitude of the microwave signal. It is the normalized envelope of the microwave signal. This represents the phase information of the microwave signal. After carrier-suppressed double-sideband modulation and polarization multiplexing, the two polarization states are denoted as... , The expression is written as:

[0046] (3)

[0047] in The time-domain schematic diagram is as follows Figure 2 The diagram at point C is shown in the image. The insertion loss of the modulator. This is the half-wave voltage of the modulator, and the extinction ratio of the modulator is assumed to be infinite during the derivation. Expanding equation (3) using Bessel and ignoring higher-order terms, the expression for the two-polarization multiplexed signal can be rewritten as:

[0048] (4)

[0049] in, It is the modulation coefficient. It is a first-order Bessel function of the first kind. Then, the polarization-multiplexed signal enters the dispersive medium at the output, achieving frequency-time mapping. Using... To represent the envelope of a single Gaussian pulse, the expression for the two-channel signal is written as:

[0050] (5)

[0051] Subsequently, the optical signal is split into two paths on average in the optical coupling module. In the upper branch, after passing through the first polarization controller and the first polarization beam splitter, only one polarization state of the signal remains. The expression of this signal after photoelectric conversion by the first photodetector is as follows:

[0052] (6)

[0053] As shown in equation (6), there are two pulses within each mapping window, as illustrated in the time-domain diagram. Figure 2 The diagram at point D shows the pulse time interval. It is related to the frequency of the signal under test, and can be used Perform frequency calculations.

[0054] Furthermore, for parameters such as PA, PW, and TOA of microwave signals, it can be known in the case of small-signal modulation that... Therefore, the signal power envelope at this time can be written as:

[0055] (7)

[0056] Combining the modulation coefficient expression described above, the pulse envelope expression of the microwave signal can be obtained as follows: The PA, PW, TOA, and other information for pulse signals are all included in this. The above completes the theoretical derivation for the detection of multiple parameters such as microwave signal frequency, PA, PW, and TOA. Note that because the upper branch output of the optical coupling module only has a single polarization state signal, no interference occurs.

[0057] The identification of the intra-pulse modulation format will be accomplished using the lower branch output from the optical coupling module. Continuing with expression (5), the polarization multiplexed signal in the lower branch is adjusted by the second polarization controller to have its principal axis angle aligned with the second polarization beam splitter. Angle. The two output ports of the second polarization beam splitter will output coherent or decoupling signals from two polarization-state signals, respectively. Their relationship with the polarization multiplexed signal is as follows:

[0058] (8)

[0059] In this system, Set at 45°, after passing through the second polarization beam splitter, the two signals enter the second and third photodetectors respectively to complete photoelectric conversion, and then pass through the second and third analog-to-digital converters to acquire electrical pulse information. Only the power envelope of the output signal is read; its expression can be written as:

[0060] (9)

[0061] (10)

[0062] By performing the difference ratio and summation calculation on the two signals at the digital signal processor, we can obtain time-dependent amplitude information that is independent of input power.

[0063] (11)

[0064] As shown in the above equation, the phase change of the input signal is mapped to the normalized pulse power. Taking the input BPSK signal as an example, its phase is... If a phase change is performed for the symbol period, then... The expression can be written as

[0065] (12)

[0066] Where b is the BPSK signal in time The code elements within. As shown in the time-amplitude relationship of (11), for the BPSK signal, When a phase transition occurs, the value is 0 or π, and the time is... Inside A jump will also occur. Then when... When k is any integer, The value can be either -1 or 1. Also, The changing position is the same as the phase change position, so this scheme can not only identify the intra-pulse BPSK signal format, but also analyze the encoding. Furthermore, theoretically... This ensures that multiple mapping windows in the frequency-time mapping result can capture the pulse amplitude jump, visually displaying the position of the original signal phase jump.

[0067] When there are multiple signal components in the pulse, by combining (6) for derivation, the output result after passing through the second and third photodetectors can be obtained as follows:

[0068] (13)

[0069] (14)

[0070] Where N represents the number of microwave signals received. This represents the j-th signal angular frequency within a single mapping window. It can be seen that signals of different carrier frequencies are mapped to different pulses in the time domain, proving that our system has the capability to perform multi-carrier signal frequency detection. Simultaneously, the phase information of each carrier frequency is mapped to the amplitude of the corresponding pulse, indicating that the system can parse the phase information of each carrier frequency and thus obtain the modulation format of each carrier signal.

[0071] In this embodiment, the optical pulse train has a period of 20 ns and a full width at half maximum (FWHM) of 75 fs. To achieve the time convolution condition, the dispersion values ​​of the dispersion media at the input and output ends are set to 10 ns / nm, with opposite signs. The microwave signal is a BPSK signal with a center frequency of 10.8 GHz, a TOA of 1 μs, and a PW of 0.7 μs. The code group is set to 7 (Barker code 1110010), and the symbol period is 0.1 μs. The delay module introduces a time delay of 25.4 ns. It is worth noting that when a symbol change occurs, because of the delay between the two channels, the phase difference between the two channels will jump by 180° during the delay time, ultimately causing a jump in the difference ratio and amplitude value of the two signals at the output of the second polarization beam splitter. Since the system mapping period is 20 ns, the delay of approximately 25.4 ns will cause at least one mapping window to experience an amplitude jump. A schematic diagram of this principle is shown below. Figure 3 As shown. Figures 4 to 7 This is an experimental result diagram showing the multi-dimensional parameter detection of a 7-bit Barker code-encoded BPSK signal using a photon-assisted microwave signal time-frequency-amplitude-phase measurement system and method according to an embodiment of the present invention. The optical signal, after frequency-to-time mapping and a second polarization beam splitter, undergoes photoelectric conversion via a second and third photodetector. Two electrical pulse information channels are acquired by a second and a third analog-to-digital converter, respectively. The acquired output results are shown below. Figure 4 , Figure 5 As shown, the amplitude values ​​at both ports maintain a polarization relationship, accompanied by amplitude jump phenomena, and the amplitude jump position corresponds to the symbol change position. The detected TOA and PW errors are 1 ns and 21 ns, respectively. Next, the two signals are calculated in the digital signal processor as shown in equation (12) to eliminate the microwave signal input power dependence, and one pulse period is taken for observation. The amplitude information of the BPSK signal corresponding to time can be obtained, such as Figure 6 As shown in the figure, the initial encoding can be decoded based on this diagram. Finally, observing the mapping results of one time window, the system frequency measurement error is found to be 46 MHz. Figure 7 As shown in the figure. The above process demonstrates the system's ability to simultaneously measure multidimensional parameters of microwave signals.

[0072] For other structures and principles, please refer to Example 1.

[0073] It should be noted that the above embodiments can be freely combined as needed. The above description is only a detailed explanation of the preferred embodiments and principles of the present invention. For those skilled in the art, there will be changes in the specific implementation methods based on the ideas provided by the present invention, and these changes should also be considered within the scope of protection of the present invention.

Claims

1. A photon-assisted microwave signal time-frequency amplitude-phase measurement system, characterized in that, It includes a pulsed light source, an input dispersive medium, an electro-optic modulation module, a power divider, a delay module, an output dispersive medium, an optical coupling module, a polarization controller, a polarization beam splitter, a photodetector, an analog-to-digital converter, and a digital signal processor; The pulsed light source outputs a light pulse that enters the dispersive medium at the input end to complete pulse broadening, and then enters the electro-optic modulation module. At the same time, the power divider receives the microwave signal to be measured and splits it into two paths, which are then input into the upper and lower sub-modulators of the electro-optic modulation module to modulate the light pulse. The modulated light signal output by the electro-optic modulation module passes through the dispersive medium at the output end to complete the time convolution process. After that, the output light signal is split into two paths by the optical coupling module and then passes through the polarization controller, polarization beam splitter, photodetector, analog-to-digital converter, and digital signal processor in sequence to collect the position and amplitude information of the electric pulse, thereby obtaining the time, amplitude, frequency, and phase information of the microwave signal. The output optical signal is split into two paths by an optical coupling module, and then sequentially passes through a polarization controller, a polarization beam splitter, a photodetector, an analog-to-digital converter, and a digital signal processor. The acquisition of the position and amplitude information of the electrical pulses is specifically implemented as follows: one path passes through the first polarization controller and enters the first polarization beam splitter at a 0° principal axis angle, acquiring one polarization state signal which enters the first photodetector, converting the optical pulse into an electrical pulse. The first analog-to-digital converter then acquires the position and amplitude information of the electrical pulse and transmits it to the digital signal processor to calculate the microwave signal frequency and amplitude. The other path passes through the second polarization controller and enters the second polarization beam splitter at a 45° principal axis angle, splitting into two signals which enter the second and third photodetectors respectively. The second and third analog-to-digital converters acquire the electrical pulse information output by the second and third photodetectors respectively and transmit it to the digital signal processor. The digital signal processor calculates the amplitude information corresponding to the time of the two output signals and integrates the calculations to obtain the phase information of the microwave signal under test.

2. The photon-assisted microwave signal time-frequency amplitude-phase measurement system according to claim 1, characterized in that, The power divider receives the microwave signal to be tested and inputs it into the upper and lower sub-modulators of the electro-optic modulation module in two paths. The microwave signal is delayed by a delay module before being input to the lower sub-modulator. After the lower sub-modulator completes the modulation, the polarization state is rotated by a 90° polarization rotator.

3. The photon-assisted microwave signal time-frequency amplitude-phase measurement system according to claim 1, characterized in that, The input dispersion medium is a single-mode fiber or a chirped fiber grating, and the output dispersion medium is a dispersion-compensating fiber or a chirped fiber grating.

4. The photon-assisted microwave signal time-frequency amplitude-phase measurement system according to claim 1, characterized in that, The electro-optic modulation module is a polarization multiplexed Mach-Zehnder modulator, and its output optical signal consists of two polarization-orthogonal signals.

5. A method for measuring the time, frequency, amplitude, and phase of a photon-assisted microwave signal, used to implement the photon-assisted microwave signal time, frequency, amplitude, and phase measurement system as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S1, The pulse light source outputs a pulse train, which passes through a dispersion measure of... After dispersion at the input end, the light pulse is broadened, and the broadened light pulse will be modulated by a microwave signal; S2. Before modulation, the microwave signal is split into two and input to the upper and lower sub-modulators of the electro-optic modulator. One of the inputs is then... The time delay is used to perform carrier-suppressed double-sideband modulation on the optical pulses respectively; S3, the polarization multiplexed signal output after modulation is subjected to a dispersion of... The output dispersion completes the frequency-to-time mapping of the microwave signal. After that, the polarization multiplexed signal is divided into upper and lower outputs, which are polarization controlled separately to complete the conversion from analog signal to digital signal. S4. After the polarization state of the upper branch optical signal is adjusted, it enters the first polarization beam splitter at a principal axis angle of 0° and only one polarization state signal is obtained. After photoelectric conversion, the signal is converted from analog signal to digital signal and finally processed in the back end. The amplitude and frequency of the microwave signal are obtained according to the amplitude and time interval of the output pulse signal. S5. After polarization state adjustment, the lower branch optical signal enters the second polarization beam splitter at a 45° principal axis angle for polarization beam splitting, so that the two outputs after beam splitting are coherent or destructive optical signals. The two output optical signals are then converted into photoelectric signals. After completing the analog-to-digital signal conversion, the two coherent or destructive signals are subtracted and added in the back-end processing to obtain the amplitude relationship of the output signal corresponding to time, and the phase information of the input microwave signal is analyzed based on the amplitude.

6. The method for measuring the time, frequency, amplitude, and phase of a photon-assisted microwave signal according to claim 5, characterized in that, Each electrical pulse cycle after photoelectric conversion corresponds to one frequency-time mapping of the input microwave signal, and there are two electrical pulses in each cycle.

7. The method for measuring the time, frequency, amplitude, and phase of a photon-assisted microwave signal according to claim 5, characterized in that, If the microwave signal is a BPSK signal, then when the phase of the BPSK signal changes, the amplitude of the corresponding output signal will also change.

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