Microwave photon enhancement device for transient weak pulse spectrum sensing and sensing method

Abstract

The invention discloses a microwave photon enhancement device for transient weak pulse spectrum sensing and a sensing method. The microwave photon enhancement device comprises an electro-optical modulation module, a first transient pulse replication branch, a second transient pulse replication branch and an autocorrelation detection module. A to-be-measured signal forms a first carrier signal at the electro-optical modulation module modulating the carrier light source; the first pulse copy loop copies the first carrier signal to form a first pulse stream signal; the second pulse copy loop copies the first carrier signal, and forms a second pulse stream signal after passing through the optical delayer; the self-correlation detection module carries out self-correlation operation on the first pulse flow signal and the second pulse flow signal. According to the microwave photon enhancement device for transient weak pulse spectrum sensing and the sensing method, the pulse replication loop is adopted to perform periodic replication on transient extremely narrow pulses, instantaneous self-correlation operation of a radio frequency domain of an analog signal to be detected is realized through the microwave photon link, the signal-to-noise ratio of the signal to be detected is improved, and the sensitivity of an instantaneous frequency measurement system is improved.

Description

Technical Field

[0001] This invention belongs to the field of transient weak pulse spectrum measurement in the field of electronic measurement, and particularly relates to a microwave photon enhancement device and sensing method for transient weak pulse spectrum sensing. Background Technology

[0002] In certain complex electromagnetic environments, the radio frequency signals encountered by instantaneous frequency measurement receivers often manifest as transient, extremely narrow pulses with pulse widths of hundreds of nanoseconds or even narrower. These signals typically have extremely short durations, weak periodicity, and extremely low signal-to-noise ratios. Existing instantaneous frequency measurement receiving technologies struggle to effectively capture and accurately analyze such weak instantaneous signals, limiting the real-time, fine-grained sensing capabilities of the electromagnetic environment and necessitating improvements in overall sensing efficiency.

[0003] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art. Summary of the Invention

[0004] The purpose of this invention is to provide a microwave photon enhancement device and sensing method for transient weak pulse spectrum sensing.

[0005] To achieve the above objectives, the present invention provides a microwave photon enhancement device for transient weak pulse spectrum sensing, comprising:

[0006] An electro-optic modulation module includes a carrier light source and a signal under test input interface. The signal under test input interface is used to receive the signal under test and modulate the carrier light source with the signal under test to form a first carrier signal.

[0007] The first transient pulse replication branch includes a first signal input terminal, a first pulse replication loop, and a first signal output terminal connected in sequence. The first signal input terminal is connected to the electro-optic modulation module. The first pulse replication loop replicates the first carrier signal to form a first pulse stream signal and transmits it to the first signal output terminal.

[0008] The second transient pulse replication branch includes a second signal input terminal, a second pulse replication loop, an optical delay unit, and a second signal output terminal. The second signal input terminal is connected to the electro-optic modulation module. The second pulse replication loop replicates the first carrier signal, which is then converted into a second pulse stream signal by the optical delay unit and transmitted to the second signal output terminal.

[0009] The autocorrelation detection module is connected to the first signal output terminal and the second signal output terminal respectively, and performs autocorrelation calculation on the first pulse stream signal and the second pulse stream signal.

[0010] Optionally, the electro-optic modulation module includes:

[0011] A laser for generating the carrier light source;

[0012] An electro-optic modulator includes a test signal input interface, a carrier light source input interface, and a modulation signal output interface, wherein the test signal modulates the carrier light source within the electro-optic modulator to form the first carrier signal.

[0013] Optionally, the microwave photonic enhancement device further includes a first optical coupler, the input end of which is connected to the electro-optic modulation module to receive the first carrier signal, and the output end of which is connected to the first signal input end and the second signal input end respectively, and the first optical coupler distributes the first carrier signal to the first signal input end and the second signal input end.

[0014] Optionally, the microwave photonic enhancement device further includes a second optical coupler, the input of which is connected to the first signal output and the second signal output respectively, and the output of which is connected to the autocorrelation detection module. The second optical coupler is used to integrate the first pulse stream signal and the second pulse stream signal.

[0015] Optionally, the first pulse replication loop includes a third optical coupler, a first optical amplifier, a first optical attenuator, and a first adjustable optical delay line. The third optical coupler includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal. The first input terminal of the third optical coupler is connected to the output terminal of the first optical coupler, and the first output terminal of the third optical coupler is connected to the input terminal of the second optical coupler. The first optical amplifier, the first optical attenuator, and the first adjustable optical delay line are sequentially connected between the second output terminal and the second input terminal of the third optical coupler.

[0016] Optionally, the second pulse replication loop includes a fourth optical coupler, a second optical amplifier, a second optical attenuator, and a second tunable optical delay line, wherein the second tunable optical delay line has the same delay as the first tunable optical delay line; the fourth optical coupler includes a third input terminal, a fourth input terminal, a third output terminal, and a fourth output terminal, wherein the third input terminal of the third optical coupler is connected to the output terminal of the first optical coupler, and the third output terminal of the third optical coupler is connected to the input terminal of the optical delay unit; the second optical amplifier, the second optical attenuator, and the second tunable optical delay line are sequentially connected between the fourth output terminal and the fourth input terminal of the third optical coupler.

[0017] Optionally, the autocorrelation detection module includes a photodetector, which performs square law detection on the first pulse stream signal and the second pulse stream signal.

[0018] Optionally, the autocorrelation detection module further includes a low-pass filter, the input of which is connected to the output of the photodetector.

[0019] This application also provides a method for sensing the spectrum of transient weak pulses, wherein the sensing method is implemented using the microwave photon enhancement device described above, and the sensing method includes:

[0020] S10. The carrier light source is modulated using the signal to be measured to obtain the first carrier signal;

[0021] S20. The first carrier signal is copied in the first transient pulse copying branch to form a first pulse stream signal, and the first carrier signal is copied and delayed in the second transient pulse copying branch to form a second pulse stream signal.

[0022] S30. Perform autocorrelation operation on the first pulse stream signal and the second pulse stream signal.

[0023] In summary, compared with the prior art, the microwave photon enhancement device and sensing method for transient weak pulse spectrum sensing provided by the present invention have the following beneficial effects:

[0024] The microwave photonic enhancement device and sensing method for transient weak pulse spectrum sensing of this application adopts a pulse replication loop to periodically replicate transient extremely narrow pulses, and realizes instantaneous autocorrelation operation of the radio frequency domain of the analog signal under test through a microwave photonic link, thereby improving the signal-to-noise ratio of the signal under test, increasing the sensitivity of the instantaneous frequency measurement system, and reducing the resource consumption of digital correlation operation under broadband. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the microwave photon enhancement device of this application.

[0026] Figure 2 This is a schematic diagram of the structure of the first pulse replication loop.

[0027] Figure 3 This is to simulate the signal spectrum after autocorrelation output.

[0028] Figure 4 This is a flowchart of the sensing method in this application.

[0029] Explanation of reference numerals in the attached figures:

[0030] Microwave photon enhancement device 1

[0031] Electro-optic modulation module 10

[0032] Laser 110

[0033] Electro-optic modulator 120

[0034] First transient pulse replication branch 20

[0035] Third optical coupler 210

[0036] First input terminal 211

[0037] Second input terminal 212

[0038] First output terminal 213

[0039] Second output terminal 214

[0040] First Optical Amplifier 220

[0041] First optical attenuator 230

[0042] First adjustable delay line 240

[0043] Second transient pulse replication branch 30

[0044] Fourth optical coupler 310

[0045] Second optical amplifier 320

[0046] Second optical attenuator 330

[0047] Second adjustable delay line 340

[0048] Autocorrelation detection module 40

[0049] Photodetector 410

[0050] Low-pass filter 420

[0051] First optical coupler 50

[0052] Second optical coupler 60

[0053] Optical delayer 70 Detailed Implementation

[0054] The microwave photon enhancement device and sensing method for transient weak pulse spectrum sensing proposed in this invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of this invention will become clearer from the following description. It should be noted that the drawings are in a very simplified form and use non-precise proportions, only for the purpose of conveniently and clearly illustrating the embodiments of this invention. Please refer to the drawings to make the objectives, features, and advantages of this invention more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationships, or adjustments to the size, without affecting the effects and objectives achieved by this invention, should still fall within the scope of the technical content disclosed in this invention.

[0055] like Figure 1 As shown, the present invention provides a microwave photonic enhancement device 1 for transient weak pulse spectrum sensing. The microwave photonic enhancement device 1 includes an electro-optic modulation module 10, a first transient pulse replication branch 20, a second transient pulse replication branch 30, and an autocorrelation detection module 40.

[0056] The electro-optic modulation module 10 includes a carrier light source and a signal under test (SUT) input interface. The SUT input interface is used to receive the SUT signal. Within the electro-optic modulation module 10, the SUT signal modulates the carrier light source to form a first carrier signal. Specifically, the electro-optic modulation module 10 includes a laser 110 and an electro-optic modulator 120. The laser 110 generates the carrier light source. The electro-optic modulator 120 includes a SUT input interface, a carrier light source input interface, and a modulation signal output interface. The SUT signal modulates the carrier light source within the electro-optic modulator 120 to form the first carrier signal.

[0057] In this application, the laser 110 uses a Santec TSL-510 tunable continuous light source as the system carrier light source. The wavelength range of the laser 110 is 1510nm to 1630nm. To ensure the lowest link transmission loss, the wavelength is adjusted to 1550nm, so that the system operates in the low-loss transmission window. The electro-optic modulator 120 is a modulation module with a bandwidth of 40GHz.

[0058] The microwave photonic enhancement device 1 further includes a first optical coupler 50 and a second optical coupler 60. The input terminal of the first optical coupler 50 is connected to the electro-optic modulation module 10 to receive a first carrier signal. The first optical coupler 50 distributes the first carrier signal to the first signal input terminal of the first transient pulse replication branch 20 and the second signal input terminal of the second transient pulse replication branch 30. In this embodiment, the first optical coupler 50 is a 1×2 optical coupler, and the first carrier signal is evenly distributed to the first and second signal input terminals after being distributed by the first optical coupler 50.

[0059] The second optocoupler 60 is a 1×2 optocoupler, with its input terminals connected to the first signal output terminal and the second signal output terminal, respectively. The output terminal of the second optocoupler 60 is connected to the autocorrelation detection module 40. The second optocoupler 60 is used to integrate the first pulse current signal and the second pulse current signal and input them to the autocorrelation detection module 40 to perform autocorrelation calculations on the first and second pulse current signals.

[0060] The first transient pulse replication branch 20 includes a first signal input terminal, a first pulse replication loop, and a first signal output terminal connected in sequence. The first signal input terminal is connected to the electro-optic modulation module 10. The first pulse replication loop replicates the first carrier signal to form a first pulse stream signal and transmits it to the first signal output terminal. Figure 2As shown, the first pulse replication loop includes a third optical coupler 210, a first optical amplifier 220, a first optical attenuator 230, and a first adjustable optical delay line 240. The third optical coupler 210 includes a first input terminal 211, a second input terminal 212, a first output terminal 213, and a second output terminal 214. The first input terminal 211 of the third optical coupler 210 is connected to the output terminal of the first optical coupler 50, and the first output terminal 213 of the third optical coupler 210 is connected to the input terminal of the second optical coupler 60. The first optical amplifier 220, the first optical attenuator 230, and the first adjustable optical delay line 240 are sequentially connected between the second output terminal 214 and the second input terminal 212 of the third optical coupler 210. In the first pulse replication loop, the first carrier signal is input to the third optical coupler 210 via the first input terminal 211. One optical signal is directly output from the first output terminal 213, while the other optical signal enters the active fiber loop via the second input terminal 212. After optical amplification, optical attenuation, and optical delay, the signal returns to the second input terminal 212 of the third optical coupler 210. The returned optical signal is then split again, with one path output from the first output terminal 213 of the third optical coupler 210, and the other path re-entering the active fiber loop to repeat the above process. Throughout the first pulse replication loop, signal amplification and modulation are performed in the optical domain. The loop's operating state can be tuned and controlled in real time to ensure energy balance and maintain stable operation. The first pulse replication loop incorporates a first optical amplifier 220 and a first optical attenuator 230 to compensate for edge loss and appropriately amplify the optical pulse. Furthermore, the length of the entire first pulse replication loop must be greater than the width of the optical pulse to be replicated.

[0061] The first carrier signal is a carrier signal including a single transient pulse. The first carrier signal enters the first transient pulse replication branch 20 through the first signal input terminal, and then enters the third optical coupler 210 of the first pulse replication loop through the first input terminal 211. The transient pulse in the first carrier signal completes transient narrow pulse replication in the first pulse replication loop. The gain-loss balance in the first pulse replication loop is achieved by adjusting the first optical amplifier 220 and the first optical attenuator 230, thereby forming a stable replicated pulse flow. In addition, the delay amount of the first adjustable optical delay line 240 is adjusted to form a pulse flow with a replication period T1.

[0062] The second transient pulse replication branch 30 includes a second signal input terminal, a second pulse replication loop, an optical delay unit 70, and a second signal output terminal. The second signal input terminal is connected to the electro-optic modulation module 10. The second pulse replication loop replicates the first carrier signal, which is then converted into a second pulse stream signal after passing through the optical delay unit 70 and transmitted to the second signal output terminal.

[0063] The structure of the second pulse replication loop is the same as that of the first pulse replication loop, and the replication process of the first carrier signal by the second pulse replication loop is also the same as that of the first pulse replication loop. The second pulse replication loop includes a fourth optical coupler 310, a second optical amplifier 320, a second optical attenuator 330, and a second adjustable optical delay line 340. The second adjustable optical delay line 340 has the same delay as the first adjustable optical delay line 240. The fourth optical coupler 310 includes a third input terminal, a fourth input terminal, a third output terminal, and a fourth output terminal. The third input terminal of the third optical coupler 310 is connected to the output terminal of the first optical coupler 50, and the third output terminal of the third optical coupler 210 is connected to the input terminal of the optical delay unit 70. The second optical amplifier 320, the second optical attenuator 330, and the second adjustable optical delay line 340 are sequentially connected between the fourth output terminal and the fourth input terminal of the third optical coupler 210. The first carrier signal enters the second transient pulse replication branch 30 through the second signal input terminal, and then enters the fourth optical coupler 310 of the second pulse replication loop through the third input terminal. The transient pulse in the first carrier signal completes transient narrow pulse replication in the second pulse replication loop. The second optical amplifier 320 and the second optical attenuator 330 are adjusted to achieve gain-loss balance in the first pulse replication loop, thereby forming a stable replicated pulse stream. In addition, the second adjustable optical delay line 340 and the first adjustable optical delay line 240 have the same delay. After the first carrier signal passes through the second pulse replication loop, it forms a pulse stream with a replication period T1, and after passing through the optical delay unit 70 of the second transient pulse replication branch 30, it forms a delayed signal.

[0064] The autocorrelation detection module 40 is connected to the first signal output terminal and the second signal output terminal respectively, and performs autocorrelation calculation on the first pulse current signal and the second pulse current signal. The autocorrelation calculation can detect periodic components mixed in random signals (such as noise). For aperiodic random functions, as τ→∞, the autocorrelation function R x (τ)→0; Using this property, autocorrelation is performed on the noisy signal y(t)=x(t)+n(t) (where: x(t) is a periodic signal, n(t) is a random signal) to obtain: R y (τ)=R x (τ)+R n (τ), when τ is large, R n (τ)→0. Therefore, performing autocorrelation on the signal can effectively eliminate random noise in the signal and highlight the periodic components of the signal, where τ is the delay amount of the optical delayer 70.

[0065] The autocorrelation detection module 40 includes a photodetector 410, which performs square-law detection on the first pulse current signal and the second pulse current signal. The square-law detection can be approximately equivalent to the autocorrelated signal. The autocorrelation detection module 40 also includes a low-pass filter 420, the input of which is connected to the output of the photodetector 410.

[0066] In this application, a photodetector 410 with a 40 GHz response bandwidth is selected to realize the photoelectric conversion of two optical signals and complete the autocorrelation operation.

[0067] In summary, the signal enhancement mechanism of the microwave photonic enhancement device 1 for transient weak pulse spectrum sensing in this application is as follows: assuming the carrier frequency of the signal to be measured input to the electro-optic modulator 120 is ω0, and the optical carrier signal expression is E... c ·exp(jω c t), the input RF signal to be tested is V RF (t)=v rf (t)+n rf (t); The output signal after passing through the electro-optic intensity modulator is Ideally, after the two optical signals are stably replicated n times by the first pulse replication loop and the second pulse replication loop, the output signal is... Where, n s (t) represents the noise introduced into the system.

[0068] The second pulse stream signal formed after the delay in the second transient pulse replication branch 30 is: In the formula, V RF (t)=E0exp(jω0t), V DC V is the bias voltage (fixed value) of the electro-optic modulator 120. π τ is the half-wave voltage (fixed value) of the electro-optic modulator 120; τ is the delay amount of the optical delay unit 70 in the second transient pulse replication branch 30, and n' s (t) represents the noise introduced into the system.

[0069] The first pulse current signal from the first transient pulse replication branch 20 and the second pulse current signal from the second transient pulse replication branch 30 are combined in the optical domain and then detected and output by the photodetector 410.

[0070] The photoelectric detection process is equivalent to the conjugate multiplication process. Therefore, the signals from the two branches are equivalent to undergoing autocorrelation after photoelectric detection and low-pass filtering.

[0071] The noise introduced by the system can be considered as random white noise. After correlation calculation, it is suppressed due to the lack of correlation of the noise, i.e., R n(τ)→0. The signal-to-noise ratio of the system output signal is further improved.

[0072] like Figure 1 and Figure 2 As shown, after connecting the various device modules, the first optical amplifier 220 and the first optical attenuator 230 in the first pulse replication loop are adjusted, and the second optical amplifier 320 and the second optical attenuator 330 in the second pulse replication loop are adjusted to ensure stable output of the replicated pulse. The delay of the first adjustable optical delay line 240 and the second adjustable optical delay line 340 is set to be 10ns less than the width of the pulse to be measured. An AWG (Arbitrary Waveform Generator) is used to generate the single-pulse signal to be measured, with the pulse width set to 10ns, the carrier frequency to 12GHz, and the single-pulse signal power set to -37dBm. The system noise floor of the optical correlation device is approximately -10dBm, therefore the input signal-to-noise ratio is approximately -27dB. After enhancement by the microwave photonic enhancement device 1, the output signal power of the device is as follows. Figure 3 As shown, the output signal power is -4.4dBm and the signal-to-noise ratio is approximately 5.6dB, obtained from the autocorrelation output signal spectrum. Therefore, the signal-to-noise ratio is improved by 32.6dB.

[0073] like Figure 4 As shown, this application also provides a method for sensing the spectrum of transient weak pulses. The sensing method is implemented using the microwave photon enhancement device 1 described above, and the sensing method includes:

[0074] S10. The carrier light source is modulated using the signal to be measured to obtain the first carrier signal;

[0075] S20. The first carrier signal is copied in the first transient pulse copying branch to form a first pulse stream signal, and the first carrier signal is copied in the second transient pulse copying branch and delayed to form a second pulse stream signal.

[0076] S30. Perform autocorrelation operation on the first pulse stream signal and the second pulse stream signal.

[0077] The microwave photonic enhancement device and sensing method for transient weak pulse spectrum sensing disclosed in this application employs an optical autocorrelation link to enhance transient weak pulses in the radio frequency domain, effectively suppressing microwave photonic link noise, improving the signal-to-noise ratio by approximately 32 dB, and increasing the sensitivity of the microwave photonic broadband frequency measurement system by more than 30 dB. Furthermore, an active fiber resonant loop (i.e., a first pulse replication loop and a second pulse replication loop) is used to complete the periodic replication of transient weak pulses in the radio frequency domain, avoiding the "detection → frequency conversion to intermediate frequency" stage in digital radio frequency storage, saving system processing time and improving processing efficiency.

[0078] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0079] In the description of this invention, it should be understood that the terms "center," "height," "thickness," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0080] In the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0081] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0082] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A microwave photonic enhancement device for transient weak pulse spectrum sensing, characterized in that, The microwave photonic enhancement device includes: An electro-optic modulation module includes a carrier light source and a signal under test input interface. The signal under test input interface is used to receive the signal under test and modulate the carrier light source with the signal under test to form a first carrier signal. The first transient pulse replication branch includes a first signal input terminal, a first pulse replication loop, and a first signal output terminal connected in sequence. The first signal input terminal is connected to the electro-optic modulation module. The first pulse replication loop replicates the first carrier signal to form a first pulse stream signal and transmits it to the first signal output terminal. The second transient pulse replication branch includes a second signal input terminal, a second pulse replication loop, an optical delay unit, and a second signal output terminal. The second signal input terminal is connected to the electro-optic modulation module. The second pulse replication loop replicates the first carrier signal, which is then converted into a second pulse stream signal by the optical delay unit and transmitted to the second signal output terminal. The autocorrelation detection module is connected to the first signal output terminal and the second signal output terminal respectively, and performs autocorrelation calculation on the first pulse stream signal and the second pulse stream signal.

2. The microwave photon enhancement device as described in claim 1, characterized in that, The electro-optic modulation module includes: A laser for generating the carrier light source; An electro-optic modulator includes a test signal input interface, a carrier light source input interface, and a modulation signal output interface, wherein the test signal modulates the carrier light source within the electro-optic modulator to form the first carrier signal.

3. The microwave photon enhancement device as described in claim 1, characterized in that, The microwave photonic enhancement device further includes a first optical coupler, the input end of which is connected to the electro-optic modulation module to receive the first carrier signal, and the output end of which is connected to the first signal input end and the second signal input end respectively. The first optical coupler distributes the first carrier signal to the first signal input end and the second signal input end.

4. The microwave photon enhancement device as described in claim 3, characterized in that, The microwave photonic enhancement device further includes a second optical coupler, the input end of which is connected to the first signal output end and the second signal output end respectively, and the output end of which is connected to the autocorrelation detection module. The second optical coupler is used to integrate the first pulse stream signal and the second pulse stream signal.

5. The microwave photon enhancement device as described in claim 4, characterized in that, The first pulse replication loop includes a third optical coupler, a first optical amplifier, a first optical attenuator, and a first adjustable optical delay line. The third optical coupler includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal. The first input terminal of the third optical coupler is connected to the output terminal of the first optical coupler, and the first output terminal of the third optical coupler is connected to the input terminal of the second optical coupler. The first optical amplifier, the first optical attenuator, and the first adjustable optical delay line are sequentially connected between the second output terminal and the second input terminal of the third optical coupler.

6. The microwave photon enhancement device as described in claim 5, characterized in that, The second pulse replication loop includes a fourth optical coupler, a second optical amplifier, a second optical attenuator, and a second tunable optical delay line. The second tunable optical delay line has the same delay as the first tunable optical delay line. The fourth optical coupler includes a third input terminal, a fourth input terminal, a third output terminal, and a fourth output terminal. The third input terminal of the third optical coupler is connected to the output terminal of the first optical coupler, and the third output terminal of the third optical coupler is connected to the input terminal of the optical delay unit. The second optical amplifier, the second optical attenuator, and the second tunable optical delay line are sequentially connected between the fourth output terminal and the fourth input terminal of the third optical coupler.

7. The microwave photon enhancement device as described in claim 1, characterized in that, The autocorrelation detection module includes a photodetector, which performs square law detection on the first pulse stream signal and the second pulse stream signal.

8. The microwave photon enhancement device as described in claim 8, characterized in that, The autocorrelation detection module also includes a low-pass filter, the input of which is connected to the output of the photodetector.

9. A method for sensing the spectrum of transient weak pulses, characterized in that, The sensing method is implemented using the microwave photon enhancement device as described in any one of claims 1-8, and the sensing method includes: S10. The carrier light source is modulated using the signal to be measured to obtain the first carrier signal; S20. The first carrier signal is copied in the first transient pulse copying branch to form a first pulse stream signal, and the first carrier signal is copied and delayed in the second transient pulse copying branch to form a second pulse stream signal. S30. Perform autocorrelation operation on the first pulse stream signal and the second pulse stream signal.

Images