Phase state interference performance measuring device and method

Abstract

The invention provides a phase state interference performance measuring device and method, and mainly relates to the technical field of quantum information. The measuring device comprises a pulse preparation module which is configured to generate an optical pulse pair at a preset frequency; the unequal arm interferometer is configured to perform interference processing on the light pulse pairs based on the long and short arm delay difference to obtain interference pulse signals and non-interference pulse signals corresponding to each light pulse pair; the measuring module is configured to measure the interference pulse signals and the non-interference pulse signals corresponding to the multiple optical pulse pairs respectively to obtain detection responses of the multiple interference pulse signals and detection responses of the multiple non-interference pulse signals; and a data processing module configured to determine response counts of interference peak positions and response counts of non-interference peak positions in a plurality of sampling periods based on the detection responses of the plurality of interference pulse signals and the detection responses of the plurality of non-interference pulse signals so as to obtain a phase state interference result and a phase state non-interference result.

Description

Technical Field

[0001] The present disclosure relates to the field of quantum information technology, and more particularly, to an apparatus and method for measuring the interference performance of phase states. Background Art

[0002] In quantum communication, a quantum key distribution (QKD) system can provide high-level information security protection based on the principles of quantum no-cloning and uncertainty to resist high-computing-power cracking. At present, the evaluation of the interference contrast and drift rate of phase states is an important part of the QKD system evaluation. The currently commonly used evaluation method is to develop a complete QKD system and indirectly infer the phase state performance based on the system bit error rate. This method requires the support of a complete system, has problems such as a long development cycle and high complexity, and it is difficult to quickly verify the performance of new schemes.

[0003] In addition, during the evaluation of the interference contrast and drift rate of phase states, since the interference peaks are mixed in the non-interference peaks, it is difficult to evaluate by means of average power. In this regard, most of the existing technologies use an intensity modulation module, or through a high-speed polarization modulation module and an analyzer, modulate the non-interference peaks into a polarization state that cannot pass through the analyzer, modulate the non-interference peaks (corresponding to extinction), and only let the interference peaks enter the measurement module.

[0004] However, both of these methods will lead to hardware complexity by adding a high-speed intensity modulation module or a high-speed polarization modulation module and an analyzer, and it is also necessary to perform bias point stabilization and timing alignment. At the same time, it is difficult to directly apply to a non-equal-arm interferometer under test with polarization independence and single-mode output such as a Faraday-Michelson interferometer. Additional polarization or polarization stabilization is required during application, further increasing the complexity and easily introducing errors.

[0005] Disclosure

[0006] In view of this, the present disclosure provides an apparatus and method for measuring the interference performance of phase states.

[0007] One aspect of the present disclosure provides a device for measuring the interference performance of a phase state. Among them, the above-mentioned measuring device includes: a pulse preparation module configured to generate a pair of optical pulses at a preset frequency and generate a first synchronization signal based on the emission time of the pair of optical pulses; an unequal-arm interferometer configured to perform interference processing on the pair of optical pulses based on the delay difference between the long and short arms to obtain an interference pulse signal and a non-interference pulse signal corresponding to each pair of optical pulses; a measurement module configured to use a plurality of sampling periods determined based on the first synchronization signal to measure the interference pulse signals and non-interference pulse signals corresponding to a plurality of pairs of optical pulses respectively, and obtain the detection responses of the plurality of interference pulse signals and the detection responses of the plurality of non-interference pulse signals; a data processing module configured to determine the response counts at the interference peak positions and the response counts at the non-interference peak positions in the plurality of sampling periods based on the detection responses of the plurality of interference pulse signals and the detection responses of the plurality of non-interference pulse signals, so as to obtain the phase state interference result and the phase state non-interference result.

[0008] According to an embodiment of the present disclosure, the above-mentioned data processing module is further configured to perform noise reduction processing on the phase state interference result based on the noise signal introduced by the measurement module to obtain a net phase state interference result.

[0009] According to an embodiment of the present disclosure, the above-mentioned measuring device further includes an adjustable optical attenuator; the pulse preparation module is configured to generate a single pulse at the above-mentioned preset frequency and generate a second synchronization signal based on the emission time of the single pulse; the adjustable optical attenuator is configured to adjust the optical power of the single pulse based on the response count at the non-interference peak position of the non-interference pulse signal in the plurality of sampling periods to obtain a single pulse signal corresponding to each single pulse; the measurement module is configured to use the plurality of sampling periods determined based on the second synchronization signal to measure a plurality of single pulse signals and obtain the detection responses of a plurality of noise signals.

[0010] According to an embodiment of the present disclosure, the above-mentioned data processing module is configured to determine the response count at the interference peak position of the noise signal in the plurality of sampling periods based on the detection responses of the plurality of noise signals, and perform a mathematical operation on the response count at the interference peak position of the noise signal in the plurality of sampling periods and the response count at the interference peak position of the interference pulse signal in the plurality of sampling periods based on a preset cumulative time to obtain the above-mentioned net phase state interference result after noise deduction.

[0011] According to an embodiment of the present disclosure, the above data processing module is configured to: group the response counts of the interference peak positions of the above noise signals in the above multiple sampling periods based on the above preset cumulative time to obtain multiple noise signal count groups; sum the response counts of the multiple above noise signals included in each noise signal count group at the interference peak positions in the above multiple sampling periods to obtain the total noise count of each noise signal count group; calculate the mean value of the total noise counts of the multiple noise signal count groups to obtain the average noise count per unit time.

[0012] According to an embodiment of the present disclosure, the above data processing module is further configured to: group the response counts of the interference peak positions of the above interference pulse signals in multiple sampling periods based on the above preset cumulative time to obtain multiple interference signal count groups; sum the response counts of the multiple above interference pulse signals included in each interference signal count group at the interference peak positions in multiple sampling periods to obtain the total interference peak count of each interference signal count group; obtain the above net phase state interference result based on the difference between the total interference peak count of each interference signal count group and the average noise count per unit time.

[0013] According to an embodiment of the present disclosure, the above data processing module is further configured to use the above net phase state interference result to calculate the phase state contrast and the drift rate, wherein the above phase state contrast is calculated based on the maximum and minimum values of the above net phase state interference result, and the above drift rate is obtained based on the change rate of the above net phase state interference result.

[0014] According to an embodiment of the present disclosure, the above preset frequency is determined based on the time interval between two optical pulses in the above optical pulse pair.

[0015] Another aspect of the present disclosure provides a method for measuring the phase state interference performance, which is applied to the above phase state interference performance measuring device. The above measuring method includes: in response to a measurement request for the phase state interference performance, generating an optical pulse pair and a first synchronization signal at a preset frequency; performing interference processing on the above optical pulse pair to obtain an interference pulse signal and a non-interference pulse signal corresponding to each optical pulse pair; using multiple sampling periods determined based on the above synchronization signal to measure the interference pulse signals and non-interference pulse signals corresponding to multiple optical pulse pairs respectively to obtain the detection responses of multiple interference pulse signals and the detection responses of multiple non-interference pulse signals; determining the response count data at the interference peak positions and the response counts at the non-interference peak positions in the above multiple sampling periods based on the detection responses of the multiple interference pulse signals and the detection responses of the multiple non-interference pulse signals to obtain the phase state interference result and the phase state non-interference result.

[0016] According to an embodiment of the present disclosure, the above method further includes: generating a single pulse and a second synchronization signal at the above preset frequency; adjusting the optical power of the single pulse based on the response count of the non-interference peak positions of the non-interference pulse signal in the above multiple sampling periods to obtain a noise signal corresponding to each single pulse; measuring the noise signals corresponding to the multiple single pulses by using the multiple sampling periods determined based on the second synchronization signal to obtain detection responses of the multiple noise signals; determining the response count of the interference peak positions of the noise signal in the above multiple sampling periods based on the detection responses of the multiple noise signals; performing a mathematical operation on the response count of the interference peak positions of the noise signal in the above multiple sampling periods and the response count of the interference peak positions of the interference pulse signal in the multiple sampling periods based on a preset cumulative time to obtain a net phase state interference result after noise deduction.

[0017] Embodiments of the present disclosure can obtain a phase state interference signal and a non-interference signal only through common instruments and data processing by using the response count of the non-interference peak positions and the response count of the interference peak positions, accurately evaluate core indicators such as the phase state contrast and drift rate required by the system, without developing a complete quantum key distribution system (such as a transmitter, a receiver, a phase compensation unit, etc.) and additional hardware (such as a high-speed intensity modulation or polarization modulation module), thereby simplifying the system design and reducing the hardware complexity. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following description of the embodiments of the present disclosure with reference to the accompanying drawings.

[0019] Figure 1 A schematic diagram of a conventional unequal-arm interferometer test device based on intensity modulation is schematically shown.

[0020] Figure 2 A schematic diagram of a conventional unequal-arm interferometer measurement device based on polarization selection is schematically shown.

[0021] Figure 3 A schematic diagram of a phase state interference performance measurement device according to an embodiment of the present disclosure is schematically shown.

[0022] Figure 4 A schematic diagram of a phase state interference performance measurement device according to another embodiment of the present disclosure is schematically shown.

[0023] Figure 5 A schematic diagram of a phase state interference performance measurement device according to a specific embodiment of the present disclosure for obtaining a phase state interference result is schematically shown.

[0024] Figure 6Schematically shown is a schematic diagram of a phase state interference performance measurement apparatus according to a specific embodiment of the present disclosure for obtaining a noise-removed net phase state interference result.

[0025] Figure 7 Schematically shown is a flowchart of a phase state interference performance measurement method according to an embodiment of the present disclosure.

[0026] Figure 8 Schematically shown is a flowchart of a phase state interference performance measurement method according to another embodiment of the present disclosure. Detailed Embodiments

[0027] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present disclosure. In the following detailed description, for the sake of explanation, many specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure. However, it is obvious that one or more embodiments can also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts of the present disclosure.

[0028] The terms used herein are merely for describing specific embodiments and are not intended to limit the present disclosure. The terms "including", "comprising", etc. used herein indicate the presence of the described features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0029] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0030] In the case of using expressions such as "at least one of A, B, and C, etc.", generally, it should be interpreted according to the meaning commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include, but is not limited to, a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0031] Quantum key distribution (QKD) systems are based on the principles of quantum no-cloning and the uncertainty principle, and can provide a high level of information security protection against high-computing-power cracking. Currently, QKD systems mainly use weak photons as information carriers and achieve information transmission through methods such as polarization coding, phase coding, or time-phase coding. In phase coding and time-phase coding schemes, the system needs to generate a pair of optical pulses and assign a specific phase difference to the pulse pair according to random numbers (such as 0, 0.5π, π, 1.5π in the phase coding system, or 0 and π in the time-phase coding system). After transmission, these pulse pairs reach the receiving terminal, are demodulated by an unbalanced interferometer, and finally the encoded information is restored based on the detected interference results.

[0032] Among them, the interference contrast of the phase state and the drift rate are key indicators of the performance of QKD systems. The interference contrast of the phase state directly affects the bit error rate of the system, while the phase state drift rate is closely related to the stability of the system or the design of the phase compensation unit. Therefore, the evaluation of the interference contrast and drift rate of the phase state is an important part of the QKD system evaluation.

[0033] However, the commonly used evaluation method at present is to indirectly estimate the phase state performance based on the bit error rate of the system by developing a complete QKD system. This method requires the support of a complete system (such as including a transmitter, a receiver, a phase compensation unit, etc.), has problems of long development cycle and high complexity, and it is difficult to quickly verify the performance of new schemes.

[0034] For example, when studying new schemes such as developing a new interferometer or pulse pair generation based on photon integration technology, due to the differences between the new scheme and the conventional system, the supporting software and hardware drivers often need to be adjusted or even redeveloped. This not only increases the R & D cost and time, but also introduces technical risks.

[0035] In addition, the main difficulty in evaluating the phase state contrast and drift rate is that after the pulse pair at the transmitting terminal passes through the unbalanced interferometer at the receiving terminal, three pulses, namely t0 - t, t0, and t0 + t, will be formed. Among them, the pulses corresponding to t0 - t and t0 + t are non-interference peaks, and their amplitudes remain unchanged, and the phase state information cannot be demodulated; only the pulse at the t0 moment is the interference peak, and its amplitude depends on the phase difference of the pulse pair. Therefore, the interference peak is mixed in the non-interference peaks, and it is difficult to evaluate by the method of average power.

[0036] In response to this, the existing technology uses an intensity modulation module, or through a high-speed polarization modulation module and a polarization analyzer, modulates the non-interference peaks into a polarization state that cannot pass through the polarization analyzer, modulates the non-interference peaks (corresponding to extinction), and only allows the interference peak to enter the measurement module.

[0037] Figure 1 Schematically shows a schematic diagram of an existing unbalanced interferometer test device based on intensity modulation.

[0038] Specifically, as Figure 1 shown, the intensity modulation-based unequal-arm interferometer test device disclosed in the prior art adds a high-speed intensity modulation module to apply a modulation voltage in the time window corresponding to the non-interference peak to suppress its light intensity, so as to modulate the non-interference peak (corresponding to extinction), and finally obtain a result with only interference peaks.

[0039] However, this solution requires a high-speed intensity modulator, which increases the system complexity and cost, and requires bias point stabilization and timing alignment. In addition, based on the principle of polarization vector synthesis, the polarization modulation module requires specific polarized light input, and it is difficult to directly apply it to the unequal-arm interferometer to be measured that is independent of polarization (such as the Faraday-Michelson type). Polarization or polarization stabilization is also required, which further increases the complexity and is prone to introducing errors. It should be noted that in practical applications, the phase state coding system often emphasizes polarization independence, and the interferometer is generally polarization independent and has single-mode output.

[0040] Figure 2 Schematically shows the schematic diagram of the existing unequal-arm interferometer measurement device based on polarization selection.

[0041] As Figure 2 shown, the unequal-arm interferometer measurement device based on polarization selection disclosed in the prior art adds a high-speed polarization modulation module and a polarization analyzer to modulate the non-interference peak into a polarization state that cannot pass through the polarization analyzer, and finally obtains a result with only interference peaks.

[0042] However, the system of this solution is relatively complex and requires the coordinated action of a high-speed polarization modulator and a polarization analyzer. Especially in testing new phase state preparation schemes, the supporting hardware drive circuit and software system often need to be adjusted or even newly developed, with a long cycle and high cost. If the key performance is verified based on the complete system, the cycle is long and it is difficult to meet the requirements of rapid iteration. If the new scheme has poor indicators after developing the complete system, a large amount of resources will be wasted.

[0043] In view of this, the phase state interference performance measurement device proposed in the implementation of the present disclosure can obtain the phase state interference signal and the non-interference signal only through common instruments and data processing by counting the responses at the non-interference peak position and the responses at the interference peak position, without developing a complete QKD system (such as a transmitter, a receiver, a phase compensation unit, etc.) and additional hardware (such as a high-speed intensity modulation or polarization modulation module), thereby simplifying the system design and reducing the hardware complexity.

[0044] Specifically, an embodiment of the present disclosure provides a device for measuring the phase-state interference performance, including: a pulse preparation module configured to generate optical pulse pairs at a preset frequency and generate a first synchronization signal based on the emission time of the optical pulse pairs; an unequal-arm interferometer configured to perform interference processing on the optical pulse pairs based on the delay difference between the long and short arms to obtain an interference pulse signal and a non-interference pulse signal corresponding to each optical pulse pair; a measurement module configured to measure the interference pulse signals and the non-interference pulse signals corresponding to multiple optical pulse pairs by using a plurality of sampling periods determined based on the first synchronization signal to obtain the detection responses of the multiple interference pulse signals and the detection responses of the multiple non-interference pulse signals; and a data processing module configured to determine the response counts at the interference peak positions and the response counts at the non-interference peak positions in the plurality of sampling periods based on the detection responses of the multiple interference pulse signals and the detection responses of the multiple non-interference pulse signals to obtain a phase-state interference result and a phase-state non-interference result.

[0045] It should be noted that the device and method for measuring the phase-state interference performance determined in the embodiments of the present disclosure can be used in the field of quantum information technology. The device and method for measuring the phase-state interference performance determined in the embodiments of the present disclosure can also be used in any field other than the field of quantum information technology, such as the fields of quantum communication and optical measurement technology. The application fields of the device and method for measuring the phase-state interference performance determined in the embodiments of the present disclosure are not limited.

[0046] To make the objectives, technical solutions, and advantages of the present disclosure clearer and more understandable, the present disclosure will be further described in detail below with reference to specific embodiments and the accompanying drawings.

[0047] Figure 3 A schematic diagram of a device for measuring the phase-state interference performance according to an embodiment of the present disclosure is schematically shown.

[0048] As Figure 3 shown, the measurement device includes a pulse preparation module 1, an unequal-arm interferometer 2, a measurement module 3, and a data processing module 4.

[0049] According to an embodiment of the present disclosure, the output end of the pulse preparation module 1 is connected to the input end of the unequal-arm interferometer 2. The pulse preparation module 1 is configured to repeatedly generate optical pulse pairs with a specific phase difference at a preset frequency, that is, a pair of optical pulses with a fixed time interval. Specifically, the optical pulse pairs can be generated based on a laser and an unequal-arm interferometer, or the optical pulses can be chopped by means of injection locking of two lasers or an intensity modulation unit. In the embodiments of the present disclosure, no specific limitation is made thereto.

[0050] Specifically, in an embodiment of the present disclosure, when the time delay difference between the long arm and the short arm of the unequal-arm interferometer 2 is t, the pulse preparation module 1 can send optical pulse pairs to the unequal-arm interferometer 2 at a preset repetition frequency f. Each optical pulse pair includes two pulses with a time interval of t. The number of optical pulse pairs generated in one second is f, and the total number of optical pulses is 2f.

[0051] Among them, the pulse preparation module 1 is further configured to generate a first synchronization signal and send it to the measurement module 3. The first synchronization signal is used to mark the emission time of each optical pulse pair, so as to perform subsequent time synchronization and data acquisition.

[0052] According to an embodiment of the present disclosure, after receiving the optical pulse pair, the unequal-arm interferometer 2 splits the two optical pulses included in the optical pulse pair into the long arm and the short arm for transmission, so as to convert the phase information of the optical pulse pair into a measurable light intensity change (interference peaks and non-interference peaks) through the interference effect. Specifically, the optical pulses can be interfered based on the time delay difference between the long arm and the short arm to generate an interference pulse signal and a non-interference pulse signal corresponding to each optical pulse pair, and the interference pulse signal and the non-interference pulse signal are transmitted to the measurement module 3. Among them, the time delay difference between the long arm and the short arm determines the time interval between the interference peaks and the non-interference peaks.

[0053] Among them, the unequal-arm interferometer 2 can include an unequal-arm Mach-Zehnder interferometer or an unequal-arm Faraday-Michelson interferometer, etc., which are not specifically limited in the embodiments of the present disclosure.

[0054] According to an embodiment of the present disclosure, the measurement module 3 is configured to measure the time position data of the interference peaks and the non-interference peaks, and output the detection result corresponding to the first synchronization signal to the data processing module 4. Specifically, based on the received first synchronization signal, multiple sampling periods can be determined, and the interference pulse signals and non-interference pulse signals corresponding to multiple optical pulse pairs are measured at specific time positions in each sampling period, and the detection responses of the multiple interference pulse signals and the detection responses of the multiple non-interference pulse signals (such as photon counting or optical pulse power) are recorded.

[0055] Among them, the measurement module 3 can include a high-speed photodetector or a single-photon detector and a time-to-digital converter, etc., which are not specifically limited in the embodiments of the present disclosure.

[0056] Specifically, in an embodiment of the present disclosure, the detection responses of multiple pairs of optical pulses detected by the measurement module 3 at specific time positions within multiple sampling periods may specifically include: the first period (T0, T0 + t, T0 + 2t), the second period (T0, T0 + t, T0 + 2t) + 1 / f, the third period (T0, T0 + t, T0 + 2t) + 2 / f, …, the Nth period (T0, T0 + t, T0 + 2t) + N / f. Among them, three pulses can be detected at three time positions within each sampling period. For the (T0, T0 + t, T0 + 2t) detected in the first period, T0 represents the position of the first detected pulse (non-interference peak position), T0 + t represents the position of the second detected pulse (interference peak position), and T0 + 2t represents the position of the third detected pulse (non-interference peak position).

[0057] According to an embodiment of the present disclosure, the data processing module 4 is configured to, based on the detection responses of multiple interference pulse signals and the detection responses of multiple non-interference pulse signals collected by the measurement module 3, statistically obtain the response counts at the interference peak positions and the response counts at the non-interference peak positions in multiple sampling periods, and obtain the phase state interference result (including phase information) and the phase state non-interference result (background noise) by analyzing the response counts at the interference peak positions and the response counts at the non-interference peak positions.

[0058] Among them, the data processing module 4 may employ a dedicated processor or a general-purpose processor. Preferably, the data processing module may employ a personal computer.

[0059] Specifically, in an embodiment of the present disclosure, the data processing module 4 statistically processes the detection responses of multiple pairs of optical pulses, and records the pulse power or response counts at the moments of T0 + t, T0 + t + 1 / f, T0 + t + 2 / f, …, T0 + t + N / f as GS 0 ,GS 1 ,…,GS N ,and saves the data, thereby obtaining the phase state interference result (including noise).

[0060] In this embodiment, the detection responses of multiple pairs of optical pulses are statistically processed, and the pulse power or response counts at the moments of T0, T0 + 1 / f, T0 + 2 / f, …, T0 + N / f are recorded as FGS 0 ,FGS 1 ,…,FGS N ,and saves the data, thereby obtaining the result of one non-interference position of the phase state.

[0061] According to an embodiment of the present disclosure, if the pulse preparation module 1 is the object to be measured, the unequal-arm interferometer 2 can be used as a companion measurement component. If the unequal-arm interferometer 2 is the object to be measured, the pulse preparation module 1 can be used as a companion measurement component.

[0062] According to an embodiment of the present disclosure, the time delay difference between the optical pulse pairs generated by the pulse preparation module 1 is configured to be the same as or close to the time delay difference between the long and short arms of the unbalanced interferometer 2.

[0063] Based on this, the phase state interference performance measurement device proposed in the embodiment of the present disclosure can obtain the phase state interference signal and the non-interference signal only through common instruments and data processing by counting the responses at the non-interference peak positions and the responses at the interference peak positions, without developing a complete QKD system (such as a transmitter, a receiver, a phase compensation unit, etc.) and additional hardware (such as a high-speed intensity modulation or polarization modulation module), thereby simplifying the system design and reducing the hardware complexity.

[0064] According to an embodiment of the present disclosure, in the pulse preparation module, the preset frequency of the optical pulse pairs emitted by the laser is determined based on the time interval between the two optical pulses in the optical pulse pairs.

[0065] Specifically, the preset frequency of the optical pulse pairs needs to satisfy , to ensure that the period of the optical pulse pairs is at least 2t, thereby avoiding the overlap between adjacent optical pulse pairs. Wherein, f represents the preset repetition frequency, and t represents the time interval between the two optical pulses. For example, if t = 800 ps, then .

[0066] Preferably, the preset frequency of the optical pulse pairs can satisfy f = 1 / (2M·t), where M represents an integer greater than 1. For example, if t = 800 ps and M = 2, then f = 312.5 MHz.

[0067] According to an embodiment of the present disclosure, the data processing module is further configured to perform noise reduction processing on the phase state interference result based on the noise signal introduced by the measurement module to obtain a net phase state interference result.

[0068] According to an embodiment of the present disclosure, the noise introduced by the measurement module may include, for example, the background of the photodetector, or the dark counts generated by the single-photon detector when there is no light input, the after-pulses generated after the previous photon event, and other noises. This noise signal will be superimposed on the response counts at the interference peak positions, thereby causing the phase state interference result to be distorted. If the noise is not deducted, the measurement result may not accurately reflect the true performance of the phase state.

[0069] Therefore, in the embodiments of the present disclosure, the output end of the pulse preparation module is directly connected to the measurement module, that is, the optical path does not pass through an unequal-arm interferometer, and an adjustable optical attenuator is used to adjust the optical power of a single pulse, and the adjusted single pulse is transmitted to the measurement module, so that the measurement module detects the detection response of the single pulse and uses it as a noise signal, and the data processing module uses the noise signal to perform denoising processing on the phase-state interference result, thereby obtaining a net phase-state interference result after subtracting the system background noise.

[0070] According to an embodiment of the present disclosure, the pulse preparation module is configured to generate a single pulse at a preset frequency and generate a second synchronization signal based on the emission time of the single pulse; the adjustable optical attenuator is configured to adjust the optical power of the single pulse based on the response count of the non-interference peak position of the non-interference pulse signal in multiple sampling periods to obtain a single pulse signal corresponding to each single pulse; the measurement module is configured to use multiple sampling periods determined based on the second synchronization signal to measure multiple single pulse signals to obtain detection responses of multiple noise signals.

[0071] According to an embodiment of the present disclosure, the data processing module is configured to determine the response count of the noise signal at the interference peak position in multiple sampling periods based on the detection responses of multiple noise signals, and perform a mathematical operation on the response count of the noise signal at the interference peak position in multiple sampling periods and the response count of the interference pulse signal at the interference peak position in multiple sampling periods based on a preset cumulative time to obtain a net phase-state interference result after subtracting the noise.

[0072] Next, with reference to Figure 4 , the above noise evaluation process will be further explained.

[0073] Figure 4 FIG. schematically shows a schematic diagram of a phase-state interference performance measurement device according to another embodiment of the present disclosure.

[0074] As Figure 4 shown, the measurement device includes a pulse preparation module 1, a measurement module 3, a data processing module 4, and an adjustable optical attenuator 5.

[0075] Among them, the input end of the adjustable optical attenuator 5 is connected to the output end of the pulse preparation module 1, and the output end of the adjustable optical attenuator 5 is connected to the input end of the measurement module 3.

[0076] According to an embodiment of the present disclosure, the adjustable optical attenuator 5 can be used to adjust the optical power entering the measurement module 3 and can be applied when the measurement instrument noise is advanced. Among them, the adjustable optical attenuator can adopt a MEMS adjustable optical attenuator or a magneto-optical adjustable optical attenuator, etc.

[0077] According to an embodiment of the present disclosure, in the noise evaluation stage, a single pulse input can be used to simulate the system state without interference signals, so that the single pulse is input to the measurement module 3 without passing through the interferometer, to separately detect the background noise introduced by the measurement module 3 (such as a single photon detector).

[0078] According to an embodiment of the present disclosure, the pulse preparation module 1 is configured to generate single pulses at a preset frequency, that is, only one optical pulse is emitted in each period, and at the same time generate a second synchronization signal and send it to the measurement module 3 to mark the emission time of each single pulse. The second synchronization signal is used to ensure the timing alignment of the noise measurement and the subsequent interference measurement.

[0079] According to an embodiment of the present disclosure, the tunable optical attenuator 5 is configured to dynamically adjust the optical power of the single pulse based on the response count at the non-interference peak position, to obtain an adjusted single pulse signal, so that the response count of the single pulse is the same as or close to the response count at the non-interference peak position, thereby ensuring that the measurement result of the single pulse can accurately reflect the system background noise characteristics.

[0080] Specifically, in an embodiment of the present disclosure, the pulse pair preparation module 1 only repeatedly sends single pulses at a preset frequency f, and adjusts the tunable optical attenuator 5, so that the pulse power or response count of the measurement module 3 at times T1, T1 + 1 / f, T1 + 2 / f,..., T1 + N / f is equal to or close to the response count T0, T0 + 1 / f, T0 + 2 / f,..., T0 + N / f at one of the non-interference positions of the phase state in terms of the cumulative power per unit time or the cumulative count within the unit time. Wherein, T1 represents the first pulse position of the single pulse signal detected by the measurement module 3, and N is much larger than f.

[0081] According to an embodiment of the present disclosure, the measurement module 3 is configured to detect the detection response of the single pulse signal and output the detection result corresponding to the second synchronization signal to the data processing module 4. Specifically, based on the received second synchronization signal, multiple sampling periods can be determined, and the detection response of the single pulse signal at the interference peak position is measured within each sampling period and recorded as a noise signal. Even when the input is a single pulse (without interference effect), the background noise will still be recorded at the interference peak position of the measurement module 3.

[0082] Specifically, in an embodiment of the present disclosure, the measurement module 3 detects the detection responses of the noise signals corresponding to multiple single pulse signals within multiple sampling periods, which may specifically include: the first period T1 + t, the second period T1 + t + 1 / f, the third period T1 + t + 2 / f,..., the Nth period T1 + t + N / f.

[0083] According to an embodiment of the present disclosure, the data processing module 4 is used to statistically obtain the response counts of the interference peak positions of the noise signals corresponding to multiple single-pulse signals in multiple sampling periods.

[0084] Specifically, in an embodiment of the present disclosure, based on the detection responses of the noise signals corresponding to multiple single-pulse signals at the interference peak positions (such as T0 + t), the data processing module 4 records the pulse power or response counts of the measurement module 3 at times T1 + t, T1 + t + 1 / f, T1 + t + 2 / f,..., T1 + t + N / f, denoted as ZS 0 , ZS 1 , …, ZS N , and saves the data, that is, the noise introduced by the measurement module 3 is obtained.

[0085] According to an embodiment of the present disclosure, the data processing module 4 is further configured to group the response counts of the noise signals at the interference peak positions in multiple sampling periods based on a preset cumulative time to obtain multiple noise signal count groups; sum the response counts of the multiple noise signals included in each noise signal count group at the interference peak positions in multiple sampling periods respectively to obtain the total noise count of each noise signal count group; and calculate the mean value of the total noise counts of the multiple noise signal count groups to obtain the average noise count per unit time.

[0086] Specifically, first, the noise signals can be statistically analyzed.

[0087] In this embodiment, the response counts of the noise signals at the interference peak positions in multiple sampling periods are grouped according to the preset cumulative time, and each group contains multiple noise data points, where the number of these data points can be obtained based on the preset frequency. For example, if the repetition frequency f = 312.5 MHz, then pulse pairs are generated per second, corresponding to noise data points.

[0088] In this embodiment, the sum of each group of noise signal count groups is calculated to obtain the total noise count per unit time, and the average noise count per unit time is calculated. For example, f consecutive noise data points are divided into a group, and each group corresponds to a cumulative time of 1 second. The grouping is as follows: The 1st second: ZS 1 , ZS 2 ,..., ZS f , the 2nd second: ZS f+1 , ZS f+2 ,..., ZS 2f , …, the Kth second: ZS Kf+1 , ZS Kf+2 ,..., ZS Kf+f . The sum of the noise counts per unit time for each group is LZJS 1 = (ZS1 +ZS 2 +…+ZS f ), LZJS 2 =(ZS f+1 +ZS f+2 +…+ZS 2f ), LZJS 3 =(ZS 2f+1 +ZS 2f+2 +…+ZS 2f+f ), …, LZJS K =(ZS Kf+1 +ZS Kf+2 +…+ZS Kf+f ), where K is an integer.

[0089] In this embodiment, the average value of the noise power sum and / or the count sum per unit time is obtained by solving. For example, ZS = (LZJS 1 +LZJS 2 +LZJS 3 +…+LZJS K ) / K, where ZS represents the average noise count per unit time (1 second).

[0090] According to an embodiment of the present disclosure, the data processing module 4 is further configured to group the response counts of the interference peak positions of the interference pulse signals in multiple sampling periods based on a preset cumulative time to obtain a plurality of interference signal count groups; sum the response counts of the interference peak positions of the multiple interference pulse signals included in each interference signal count group in multiple sampling periods to obtain the total interference peak count of each interference signal count group; and obtain a net phase state interference result based on the difference between the total interference peak count of each interference signal count group and the average noise count per unit time.

[0091] Specifically, after statistically averaging the noise count, the interference signals can also be statistically analyzed. And based on the total interference peak count and the average noise count per unit time, a net phase state interference result is calculated.

[0092] In this embodiment, the response counts of the interference peak positions of the interference pulse signals in multiple sampling periods are grouped according to the same preset cumulative time, and each group contains multiple interference data points. The sum of each interference signal count group is calculated to obtain the total interference count per unit time. For example, f consecutive interference data points are divided into a group, and each group corresponds to a cumulative time of 1 second. The grouping is as follows: The 1st second: GS 1 , GS 2 , ..., GS f , the 2nd second: GS f+1 , GS f+2 , ..., GS 2f, …, the Kth second: GS Kf+1 , GS Kf+2 ,..., GS Kf+f . The sum of the interference signal counts of each group within the unit time is respectively LZGS 1 = (GS 1 + GS 2 + … + GS f ), LZGS 2 = (GS f+1 + GS f+2 + … + GS 2f ), LZGS 3 = (GS 2f+1 + GS 2f+2 + … + GS 2f+f ), …, LZGS K = (GS Kf+1 + GS Kf+2 + … + GS Kf+f ), where K is an integer.

[0093] In this embodiment, based on the difference between the total interference count within the unit time and the average noise count within the unit time, the net phase state interference result is obtained. For example, the data after noise deduction is LZJS 1 - ZS, LZJS 2 - ZS, LZJS 3 - ZS, …, LZJS K - ZS.

[0094] Based on this, the embodiments of the present disclosure utilize an optical attenuator. It only needs to adjust the optical power to match the non-interference peak noise, ensuring that the noise level of the single-pulse signal is consistent with the non-interference peak, so as to accurately measure the noise of the detector itself without relying on high-speed modulation, while reducing the hardware complexity and avoiding the influence of noise introduced by intensity modulation or polarization modulation in the conventional scheme on the result due to being easily affected by the environment. In addition, the measurement device can distinguish signals and noise only based on the time position (such as T0, T0 + t, T0 + 2t), without processing polarization information and not relying on the signal polarization state, so as to be applicable to single-mode / polarization-maintaining interferometers and have wide compatibility.

[0095] According to the embodiments of the present disclosure, the data processing module 4 is further configured to calculate the phase state contrast and the drift rate by using the net phase state interference result.

[0096] Among them, the phase state contrast can be calculated by the ratio of the maximum value to the minimum value in the net phase state interference result, which is used to characterize the intensity change range of the interference signal. For example, the higher the contrast, the more significant the intensity change of the interference signal, and the better the system performance. If the contrast is close to 1, it indicates that there is no significant change in the interference signal intensity, which may indicate problems such as phase drift or system mismatch.

[0097] Among them, the drift rate can be represented by the change rate of the net phase state interference result over time, which reflects the stability of the phase state (such as phase fluctuations caused by temperature and mechanical vibration). For example, the larger the drift rate, the more unstable the system, and phase compensation or environmental control needs to be optimized. When the drift rate approaches zero, it indicates that the system phase state is highly stable.

[0098] According to an embodiment of the present disclosure, if the drift rate is very fast, the preset accumulation time can be shortened, such as adjusted from 1 second to 0.1 second, to capture the phase state change faster and avoid data distortion; if the drift rate is very slow, the preset accumulation time can be increased, such as adjusted from 1 second to 10 seconds, to reduce the noise impact by increasing the data statistics and improve the measurement accuracy.

[0099] Based on this, the embodiments of the present disclosure calculate the phase state contrast and the drift rate, and combine the dynamic adjustment of the accumulation time to achieve efficient evaluation and adaptive optimization of the phase state performance.

[0100] Next, with reference to Figures 5 - 6 , a further explanation will be given to the specific implementation manner of the above-mentioned phase state interference performance measurement device.

[0101] Figure 5 Schematically shows a schematic diagram of a phase state interference performance measurement device according to a specific embodiment of the present disclosure for obtaining a phase state interference result.

[0102] As Figure 5 shown, in a specific embodiment of the present disclosure, the phase state interference performance measurement device is composed of a laser, a Mach-Zehnder unequal-arm interferometer, a Faraday-Michelson unequal-arm interferometer, a MEMS tunable optical attenuator, a gated single-photon detector, a time-to-digital converter, and a personal laser. Among them, the laser and the Mach-Zehnder unequal-arm interferometer can be used as a pulse preparation module.

[0103] Among them, the emission frequency f of the laser can be configured to 312.5 MHz, and the emission period T of the laser can be obtained based on T = 1 / f. Specifically, the emission period T of the laser can be configured to . In the case where the optical pulse sequence emitted by the laser is P 0 , P 1 , P 2 , …, P N the case, Pi Represents the i-th pulse with a time interval of 3200 ps.

[0104] Meanwhile, the laser is also configured to transmit the generated first synchronization signal to the gated single-photon detector.

[0105] Among them, the Mach-Zehnder non-equal-arm interferometer consists of two fiber optic beam splitters, and the time delay difference of the optical pulse transmitted through the upper and lower arms is 800 ps. The Faraday-Michelson non-equal-arm interferometer consists of a fiber optic beam splitter and two Faraday mirrors, and the time delay difference of the optical pulse transmitted through the long and short arms is 800 ps.

[0106] Among them, the gating frequency of the gated single-photon detector is configured to 1250 MHz to match the 800 ps time delay difference.

[0107] Among them, the time-to-digital converter (TDC) can be used to record the photon arrival time with a precision of ps level.

[0108] In this specific implementation device, by calibration, it is ensured that the time delay differences of the two interferometers are both 800 ps. The laser emits optical pulse pairs at 312.5 MHz. After being split by the Mach-Zehnder interferometer, they are then secondarily interfered by the Faraday-Michelson interferometer to form interference pulse signals and non-interference pulse signals.

[0109] For example, when the optical pulse P i enters the interferometer, it will be split into two paths. At the output end of the interferometer, the two optical pulses will recombine to form a pulse pair. Among them, the first pulse is P from the short arm i (without time delay, the time position is T i ). The second pulse is P from the long arm i (with a time delay of 800 ps, the time position is T i +800 ps). Since the pulse interval of the laser is 3200 ps, the next pulse P i+1 will arrive at the interferometer at T i +3200 ps. Similarly, it will be split into two paths. Among them, the short arm outputs P i+1 (the time position is T i +3200 ps), and the long arm outputs P i+1 delayed by 800 ps (the time position is T i +3200 ps+800 ps=T i +4000 ps).

[0110] In this specific implementation device, the gated single-photon detector samples the interference pulse signal and the non-interference pulse signal at a frequency of 1250 MHz (period 800 ps), and each sampling window covers each pulse position. For example, the detection response can be obtained at the following time positions. Taking the first detection pulse as the 0 moment, the detection response may be obtained at the following moments , , ,…, .

[0111] In this specific implementation device, the personal computer is used to separately count the response counts at 800 ps, 800 ps + 3200 ps, ,…, moments, and record them as GS 0 , GS 1 ,…, GS N , and save the data, then the interference result of the phase state including noise can be obtained.

[0112] In this specific implementation device, the personal computer is used to separately count the response counts at 0, 3200 ps, ,…, moments, and record them as FGS 0 , FGS 1 ,…, FGS N , and save the data, then the result of one non-interference position of the phase state can be obtained.

[0113] Figure 6 Schematically shows a schematic diagram of the phase state interference performance measurement device according to a specific embodiment of the present disclosure for obtaining the net phase state interference result after removing noise.

[0114] As Figure 6 shown, in a specific embodiment of the present disclosure, the output end of the laser is connected to the input end of the MEMS tunable optical attenuator, the output end of the MEMS tunable optical attenuator is connected to the input end of the gated single-photon detector, the output end of the gated single-photon detector is connected to the input end of the time-to-digital converter, and the output end of the time-to-digital converter is connected to the input end of the personal computer.

[0115] In this specific implementation device, the optical path does not pass through an unbalanced interferometer, and the laser only outputs a single pulse. Among them, the preset frequency of the laser is configured to be 312.5 MHz.

[0116] In this specific implementation device, the single pulse is input into the MEMS tunable optical attenuator. By adjusting the optical power of the single pulse, multiple single pulse signals are made at the non-interference peak positions (such as 0, 3200 ps, ,…, The response count at a certain moment is equal to or close to the cumulative count per unit time of the non-interference peak data (such as FGS 0 , FGS 1 , …, FGS N ). Among them, N is much larger than .

[0117] In this specific implementation device, the gated single-photon detector is used to measure multiple single-pulse signals to obtain the detection responses of multiple noise signals. The personal computer records the pulse power or response count of the gated single-photon detector at 800 ps, 800 ps + 3200 ps, , …, moments, and records them as ZS 0 , ZS 1 , …, ZS N , and saves the data to obtain the noise introduced by the gated single-photon detector.

[0118] In this specific implementation device, the personal computer can statistically calculate the noise power sum or count sum based on a preset cumulative time, and statistically calculate the noise power sum or count sum within one second. For example: The first second LZJS 1 = (ZS 1 + ZS 2 + … + ZS f ), the second second LJZS 2 = (ZS f+1 + ZS f+2 + … + ZS f+f ), the third second LZJS 3 = (ZS 2f+1 + ZS 2f+2 + … + ZS 2f+f ), …, the Kth second LZJS K = (ZS Kf+1 + ZS Kf+2 + … + ZS Kf+f ), where K is an integer. Based on the above noise power or morning count sum per second, the average value of the noise power sum or count sum per unit time is solved, ZS = (LZJS 1 + LZJS 2 + LZJS 3 + … + LZJS K ) / K.

[0119] In this specific implementation device, the personal computer can also statistically calculate the interference signal, and statistically calculate the interference peak power sum or count sum according to a preset cumulative time to obtain the interference peak power sum or count sum within one second. For example, LZGS 1 = (GS 1 + GS 2 + … + GSf ), LZGS 2 = (GS f+1 + GS f+2 + … + GS 2f ), LZGS 3 = (GS 2f+1 + GS 2f+2 + … + GS 2f+f ), …, LZGS K = (GS Kf+1 + GS Kf+2 + … + GS Kf+f ), where K is an integer. Based on this, the interference result of the net phase state after noise deduction can be obtained as LZJS 1 - ZS, LZJS 2 - ZS, LZJS 3 - ZS, …, LZJS K - ZS.

[0120] In this specific implementation device, the personal computer can also calculate the phase state contrast and the drift rate according to the data. Among them, the relative state contrast is the maximum value of the data after noise deduction divided by the minimum value, and the drift rate is the change rate of the data after noise deduction.

[0121] Based on this, the embodiments of the present disclosure do not require a complete quantum key distribution system, only common instruments, and the measurement and evaluation of the phase state contrast and the drift rate can be realized through data processing. In addition, the embodiments of the present disclosure have no requirements on the polarization characteristics of the interferometer and can adapt to interferometers with single-mode output. In addition, this solution can well deduct the noise interference of the measuring instrument and has a small measurement error.

[0122] Figure 7 Schematically shows a flowchart of a method for measuring the phase state interference performance according to an embodiment of the present disclosure.

[0123] As Figure 7 shown, this method for measuring the phase state interference performance includes operations S710 to S740.

[0124] In operation S710, in response to a measurement request for the phase state interference performance, optical pulse pairs and a first synchronization signal are generated at a preset frequency.

[0125] In operation S720, the optical pulse pairs are subjected to interference processing to obtain an interference pulse signal and a non-interference pulse signal corresponding to each optical pulse pair.

[0126] In operation S730, using a plurality of sampling periods determined based on the first synchronization signal, the interference pulse signals and non-interference pulse signals corresponding to the respective plurality of optical pulse pairs are measured to obtain detection responses of the plurality of interference pulse signals and detection responses of the plurality of non-interference pulse signals.

[0127] In operation S740, based on the detection responses of multiple interference pulse signals and the detection responses of multiple non-interference pulse signals, the response count data of the interference peak positions and the response counts of the non-interference peak positions are determined in multiple sampling periods to obtain the phase-state interference result and the phase-state non-interference result.

[0128] Figure 8 The flowchart of the phase-state interference performance measurement method according to another embodiment of the present disclosure is schematically shown.

[0129] As Figure 8 shown, the phase-state interference performance measurement method further includes operation S810 to operation S850.

[0130] In operation S810, a single pulse and a second synchronization signal are generated at a preset frequency.

[0131] In operation S820, based on the response counts of the non-interference peak positions of the non-interference pulse signals in multiple sampling periods, the optical power of the single pulse is adjusted to obtain a noise signal corresponding to each single pulse.

[0132] In operation S830, using multiple sampling periods determined based on the second synchronization signal, the noise signals corresponding to multiple single pulses are measured to obtain the detection responses of the multiple noise signals.

[0133] In operation S840, based on the detection responses of the multiple noise signals, the response counts of the noise signals at the interference peak positions in multiple sampling periods are determined.

[0134] In operation S850, based on a preset cumulative time, a mathematical operation is performed on the response counts of the noise signals at the interference peak positions in multiple sampling periods and the response counts of the interference pulse signals at the interference peak positions in multiple sampling periods to obtain a net phase-state interference result after noise deduction.

[0135] It should be noted that the part of the phase-state interference performance measurement method in the embodiments of the present disclosure corresponds to the part of the phase-state interference performance measurement device in the embodiments of the present disclosure. For the description of the part of the phase-state interference performance measurement method, please refer to the part of the phase-state interference performance measurement device specifically, and details are not repeated here.

[0136] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, a segment of a program, or a part of code that contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions noted in the blocks may occur in an order different from that noted in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, or they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram or flowchart, and combinations of blocks in the block diagram or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions. Those skilled in the art will appreciate that the features described in the various embodiments of the present disclosure can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present disclosure. In particular, without departing from the spirit and teachings of the present disclosure, the features described in the various embodiments of the present disclosure can be combined and / or combined in various ways. All such combinations and / or combinations fall within the scope of the present disclosure.

[0137] The embodiments of the present disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Although the embodiments have been described separately above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Without departing from the scope of the present disclosure, those skilled in the art can make various substitutions and modifications, and all such substitutions and modifications should fall within the scope of the present disclosure.

Claims

1. A phase state interferometry performance measurement device, wherein: The measuring device comprises: a pulse preparation module, the pulse preparation module being configured to generate a light pulse pair at a preset frequency and to generate a first synchronization signal based on a transmission time of the light pulse pair; An unequal-arm interferometer, wherein the unequal-arm interferometer is configured to perform interference processing on the optical pulse pairs based on the delay difference between the long and short arms to obtain interference pulse signals and non-interference pulse signals corresponding to each optical pulse pair; a measurement module, wherein the measurement module is configured to measure interference pulse signals and non-interference pulse signals corresponding to each of the plurality of optical pulse pairs using a plurality of sampling periods determined based on the first synchronization signal, to obtain detection responses of the plurality of interference pulse signals and detection responses of the plurality of non-interference pulse signals; and A data processing module, wherein the data processing module is configured to determine the response counts of the interference peak positions and the response counts of the non-interference peak positions in multiple sampling periods based on the detection responses of the multiple interference pulse signals and the detection responses of the multiple non-interference pulse signals, so as to obtain phase-state interference results and phase-state non-interference results.

2. The measuring device according to claim 1, wherein: The data processing module is further configured to perform denoising processing on the phase state interference result based on the noise signal introduced by the measurement module to obtain a net phase state interference result.

3. The measuring device according to claim 2, wherein: The measuring device also includes an adjustable optical attenuator; The pulse preparation module is configured to generate a single pulse at the preset frequency, and generate a second synchronization signal based on the emission time of the single pulse; The adjustable optical attenuator is configured to adjust the optical power of the single pulse based on the response count of the non-interference peak position of the non-interference pulse signal in the multiple sampling periods to obtain a single pulse signal corresponding to each single pulse; as well as The measurement module is configured to measure a plurality of single pulse signals using the plurality of sampling periods determined based on the second synchronization signal to obtain detection responses of a plurality of noise signals.

4. The measuring device according to claim 3, wherein: The data processing module is configured to determine the response count of the interference peak position of the noise signal in the multiple sampling periods based on the detection response of the multiple noise signals, and based on a preset accumulation time, perform mathematical operations on the response count of the interference peak position of the noise signal in the multiple sampling periods and the response count of the interference peak position of the interference pulse signal in the multiple sampling periods to obtain the net phase state interference result after deducting the noise.

5. The measuring device according to claim 4, wherein: The data processing module is configured as follows: Based on the preset accumulation time, grouping the response counts of the interference peak positions of the noise signal in the multiple sampling periods to obtain multiple noise signal count groups; respectively summing up the response counts of the interference peak positions of the plurality of noise signals included in each noise signal counting group in the plurality of sampling periods to obtain a total noise count of each noise signal counting group; as well as The total noise counts of the multiple noise signal count groups are averaged to obtain an average noise count per unit time.

6. The measuring device according to claim 5, wherein: The data processing module is further configured to: Based on the preset accumulation time, grouping the response counts of the interference peak positions of the interference pulse signal in multiple sampling periods to obtain multiple interference signal count groups; summing the response counts of the interference peak positions of the plurality of interference pulse signals included in each interference signal counting group in a plurality of sampling periods to obtain a total interference peak count of each interference signal counting group; and The net phase state interference result is obtained based on the difference between the total interference peak count of each interference signal count group and the average noise count per unit time.

7. The measuring device according to claim 2, wherein: The data processing module is also configured to use the net phase state interference result to calculate the phase state contrast and drift rate, wherein the phase state contrast is calculated based on the maximum and minimum values ​​of the net phase state interference result, and the drift rate is calculated based on the rate of change of the net phase state interference result.

8. The measuring device according to claim 1, wherein: The preset frequency is determined based on a time interval between two light pulses in the light pulse pair.

9. A phase state interferometry performance measurement method, applied to the phase state interferometry performance measurement device according to any one of claims 1 to 8, wherein: The measuring method comprises: In response to a measurement request for phase state interferometry performance, generating an optical pulse pair and a first synchronization signal at a preset frequency; Performing interference processing on the optical pulse pairs to obtain interference pulse signals and non-interference pulse signals corresponding to each optical pulse pair; Measuring interference pulse signals and non-interference pulse signals corresponding to the plurality of light pulse pairs respectively using a plurality of sampling periods determined based on the synchronization signal to obtain detection responses of the plurality of interference pulse signals and detection responses of the plurality of non-interference pulse signals; and Based on the detection responses of the multiple interference pulse signals and the detection responses of the multiple non-interference pulse signals, the response count data of the interference peak positions and the response counts of the non-interference peak positions in multiple sampling periods are determined to obtain phase-state interference results and phase-state non-interference results.

10. The measuring method according to claim 9, wherein: The method further comprises: generating a single pulse and a second synchronization signal at the preset frequency; Based on the response counts of the non-interference peak positions of the non-interference pulse signal in the multiple sampling periods, the optical power of the single pulse is adjusted to obtain a noise signal corresponding to each single pulse; Measuring the noise signals corresponding to the plurality of single pulses using the plurality of sampling periods determined based on the second synchronization signal to obtain detection responses of the plurality of noise signals; Determining response counts of interference peak positions of the noise signals in the plurality of sampling periods based on the detection responses of the plurality of noise signals; and Based on the preset accumulation time, mathematical operations are performed on the response counts of the interference peak position of the noise signal in the multiple sampling periods and the response counts of the interference peak position of the interference pulse signal in the multiple sampling periods to obtain a net phase state interference result after deducting the noise.

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