A feedback loop control method and device for dual Mach-Zehnder interferometer

Abstract

The present invention provides a feedback loop control method and device for a dual Mach-Zehnder interferometer, wherein the method comprises: obtaining vibration signals of multiple acquisition points continuously acquired by the dual Mach-Zehnder interferometer to form a vibration signal sequence; comparing the peak-to-peak value of the vibration signal sequence with a preset threshold value, and updating a first judgment value and a second judgment value according to the comparison result; if it is determined that a vibration event exists according to the first judgment value and the second judgment value, the feedback loop is closed; if it is determined that no vibration event exists according to the first judgment value and the second judgment value, the feedback loop is opened, and the phase difference in the dual Mach-Zehnder interferometer is adjusted through the feedback loop. By implementing the present invention, the feedback operation is performed only when there is no vibration event, thereby eliminating the mutual influence between the event-induced and feedback-induced phase changes, solving the contradiction in the feedback bandwidth setting, and greatly simplifying the post-processing process.

Description

Technical Field

[0001] The present invention relates to the technical field of distributed optical fiber sensing, and in particular to a feedback loop control method and device of a dual Mach-Zehnder interferometer. Background Art

[0002] Distributed fiber optic sensing technology has the unique advantage of measuring physical quantities at any location within a large spatial range, which has led to the rapid development of this technology in the past few decades. The two most commonly used distributed fiber optic sensing technologies today are based on reflection measurement and interferometry. Generally speaking, reflection measurement-based technologies, such as phase-sensitive optical time-domain reflectometers and Brillouin optical time-domain analysis / reflectometers, are able to map the distribution of environmental information across the entire sensing fiber and are ideal candidates for monitoring large assets such as cables, railways, and bridges. Interferometry-based technologies can only identify and locate single events, but have the advantages of fast event acquisition, high sensitivity, and simple structure, so they are more suitable for intrusion detection in applications such as perimeter security.

[0003] Dual Mach-Zehnder Interferometer (DMZI) is a widely used distributed sensing technology based on interferometry and has achieved great success in the global commercial market. The standard DMZI sensor consists of two Mach-Zehnder Interferometers (MZI) sharing the same physical optical path, in which bidirectional optical signals propagate simultaneously, and eventually form two interference curves carrying disturbance information from opposite directions, and then calculate the location of the disturbance based on the time delay between the two disturbance curves. In order to ensure that the DMZI always has the highest sensitivity to external disturbances, the system optical path needs to operate at the orthogonal bias point, that is, the phase difference between the two optical signals in the interferometer needs to be stable at ±π / 2. However, interference factors such as ambient temperature changes will inevitably cause the phase difference to change, and the longer sensing distance will directly amplify this effect, resulting in unstable working bias points. A common way to overcome this problem is to introduce a feedback loop to monitor the bias point in real time. When the phase difference is different from its nominal value (±π / 2), the relevant information will be converted into an error signal to control the phase modulator (PM) pre-placed in one arm of the DMZI to compensate for the phase changes caused by the environment. PM is usually implemented by a piezoelectric transducer (PZT).

[0004] In order to obtain good feedback performance, the feedback bandwidth should usually be wide enough to catch up with environmental changes in time, thereby ensuring that the system noise level is minimized. But in fact, the PM in the feedback loop is equivalent to an additional vibration source. Since DMZI cannot identify two or more simultaneous vibrations at different locations, post-processing must be paid attention to at this time to extract event-related data from the raw data affected by both PM and vibration events. If the vibration event frequency exceeds the feedback bandwidth, such post-processing can be performed directly, because there is sufficient duration between two consecutive feedback steps to extract the vibration signal; when such conditions are not met, that is, the vibration frequency is close to or within the feedback bandwidth, the PM sensing signal and the event sensing signal are physically indistinguishable, resulting in a systematic error in locating the vibration event.

[0005] Therefore, when using the above feedback method, the minimum measurable frequency of the vibration event to be measured must be much higher than the highest cutoff frequency of the feedback bandwidth, otherwise, the low-frequency part of the vibration event will be aliased with the feedback signal, causing irreversible distortion of the vibration signal and ultimately leading to large errors in event location. In other words, in order to be able to measure a sufficiently low vibration frequency, the feedback bandwidth needs to be narrow enough; and in order to ensure that the system performs phase compensation in a timely manner and has strong robustness, the feedback bandwidth needs to be wide enough. If the feedback bandwidth is not set reasonably, it is impossible to maintain a balance between system stability and event detection efficiency. Summary of the invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art that if the feedback bandwidth is set unreasonably, the balance between system stability and event detection efficiency cannot be maintained, thereby providing a feedback loop control method and device for a dual Mach-Zehnder interferometer.

[0007] A first aspect of the present invention provides a feedback loop control method for a dual Mach-Zehnder interferometer, comprising: acquiring vibration signals of multiple acquisition points continuously acquired by the dual Mach-Zehnder interferometer to form a vibration signal sequence; comparing the peak-to-peak value of the vibration signal sequence with a preset threshold, and updating a first judgment value and a second judgment value according to the comparison result; if a vibration event is determined to exist according to the first judgment value and the second judgment value, closing the feedback loop; if no vibration event is determined to exist according to the first judgment value and the second judgment value, opening the feedback loop, and adjusting the phase difference in the dual Mach-Zehnder interferometer through the feedback loop.

[0008] Optionally, in the feedback loop control method of the dual Mach-Zehnder interferometer provided by the present invention, the peak-to-peak value of the vibration signal sequence is compared with a preset threshold, and the step of updating the first judgment value and the second judgment value according to the comparison result includes: comparing the peak-to-peak value of the vibration signal sequence with the preset threshold, if the peak-to-peak value of the vibration signal sequence is greater than the preset threshold, setting the first judgment value to the first set value, and setting the second judgment value to the second set value, wherein when the second judgment value is the second set value, it indicates the presence of a vibration event.

[0009] Optionally, in the feedback loop control method of the dual Mach-Zehnder interferometer provided by the present invention, the vibration signal is obtained by the dual Mach-Zehnder interferometer periodically, continuously collecting signals from multiple collection points in each cycle, wherein each cycle corresponds to a vibration signal sequence; the peak-to-peak value of the vibration signal sequence is compared with a preset threshold, and the steps of updating the first judgment value and the second judgment value according to the comparison result include: if the peak-to-peak value of the vibration signal sequence is less than or equal to the preset threshold, setting the first judgment value to the third setting value; if the first judgment values ​​in the adjacent first M cycles of the current cycle are all the third setting values, setting the second judgment value to the fourth setting value, wherein when the second judgment value is the fourth setting value, it indicates that there is no vibration event.

[0010] Optionally, in the feedback loop control method of the dual Mach-Zehnder interferometer provided by the present invention, it also includes: if the first judgment value of at least one cycle in the first M adjacent cycles of the current cycle is a first set value, the second judgment value is set to a second set value, wherein when the second judgment value is the second set value, it indicates the presence of a vibration event.

[0011] Optionally, in the feedback loop control method of the dual Mach-Zehnder interferometer provided by the present invention, the vibration signal sequence is obtained by continuously collecting vibration signals of N collection points by the dual Mach-Zehnder interferometer, and the data sampling interval of the dual Mach-Zehnder interferometer is N times shorter than the feedback interval of the feedback loop.

[0012] Optionally, in the feedback loop control method of the dual Mach-Zehnder interferometer provided by the present invention, if a vibration event is determined to exist based on the first judgment value and the second judgment value, after the step of closing the feedback loop, the method further includes: determining the vibration event position information based on the vibration signal sequence.

[0013] The second aspect of the present invention provides a feedback loop control device for a dual Mach-Zehnder interferometer, comprising: a data acquisition module, used to obtain vibration signals of multiple acquisition points continuously acquired by the dual Mach-Zehnder interferometer to form a vibration signal sequence; a comparison module, used to compare the peak-to-peak value of the vibration signal sequence with a preset threshold, and update a first judgment value and a second judgment value according to the comparison result; a feedback loop control module, if it is determined that a vibration event exists according to the first judgment value and the second judgment value, the loop control module is used to close the feedback loop; if it is determined that no vibration event exists according to the first judgment value and the second judgment value, the loop control module is used to open the feedback loop, and adjust the phase difference in the dual Mach-Zehnder interferometer through the feedback loop.

[0014] Optionally, in the feedback loop control device of the dual Mach-Zehnder interferometer provided by the present invention, the dual Mach-Zehnder interferometer periodically collects vibration signals, and continuously collects vibration signals of multiple collection points in each cycle, and each cycle corresponds to a vibration signal sequence. The comparison module includes: a comparison submodule, which is used to compare the peak-to-peak value of the vibration signal sequence with a preset threshold; a first assignment submodule, if the peak-to-peak value of the vibration signal sequence is less than or equal to the preset threshold, the first assignment submodule is used to set the first judgment value to a third setting value; a second assignment submodule, if the first judgment values ​​in the adjacent first M cycles of the current cycle are all the third setting values, the second assignment submodule is used to set the second judgment value to a fourth setting value, and when the second judgment value is the fourth setting value, it indicates that there is no vibration event.

[0015] The third aspect of the present invention provides a computer device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor, thereby executing the feedback loop control method of the dual Mach-Zehnder interferometer provided in the first aspect of the present invention.

[0016] A fourth aspect of the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the feedback loop control method of a dual Mach-Zehnder interferometer as provided in the first aspect of the present invention.

[0017] The technical solution of the present invention has the following advantages:

[0018] The feedback loop control method and device of the dual Mach-Zehnder interferometer provided by the present invention, after continuously collecting vibration signals of multiple collection points through DMZI to form a vibration signal sequence, the first judgment value and the second judgment value are updated according to the comparison result, and whether there is a vibration event can be determined based on the first judgment value and the second judgment value. When it is determined that there is a vibration event, the feedback loop is closed. After the feedback loop is closed, even if the vibration signal frequency falls within the feedback bandwidth, the system can obtain vibration information without interference and correctly locate. When it is determined that there is no vibration event, the feedback loop is kept in an open state, and the phase difference in the DMZI is adjusted through the feedback loop, so that the DMZI can be kept working at the orthogonal point in the standby state, so that the upcoming vibration event can be measured with the highest sensitivity. It can be seen that by implementing the present invention, the feedback operation is performed only when there is no vibration event, thereby eliminating the mutual influence between the event-induced and feedback-induced phase changes, solving the contradiction in the feedback bandwidth setting, and because the feedback is closed when the vibration event occurs, the data related to the vibration event can be directly extracted from a large amount of measurement data, which greatly simplifies the post-processing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 Schematic diagram of the structure of a dual Mach-Zehnder interferometer in an embodiment of the present invention;

[0021] Figure 2 is a flow chart of a specific example of a feedback loop control method of a dual Mach-Zehnder interferometer in an embodiment of the present invention;

[0022] Figure 3 is a flow chart of another specific example of a feedback loop control method for a dual Mach-Zehnder interferometer in an embodiment of the present invention;

[0023] Figure 4 A schematic diagram of a vibration signal in an embodiment of the present invention;

[0024] Figure 5 is a principle block diagram of a specific example of a feedback loop control device for a dual Mach-Zehnder interferometer in an embodiment of the present invention;

[0025] Figure 6 It is a principle block diagram of a specific example of a computer device in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be noted that the terms “first”, “second”, “third” and “fourth” are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0028] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0029] The schematic diagram of the feedback-based DMZI sensor is shown in Figure 1 As shown, the DMZI includes optical fiber A, optical fiber B, optical fiber C, a first polarization controller (polarization controller 1, PC1), a second polarization controller (polarization controller 2, PC2), phase modulation (Phase Modulation, PM), a first photodetector (Photo-Detector 1, PD1), a second photodetector (Photo-Detector 2, PD2), a third photodetector (Photo-Detector 3, PD3), a first analog-to-digital converter (Analog-to-Digital Converter 1, ADC1), a second analog-to-digital converter (Analog-to-Digital Converter 2, ADC2), a digital-to-analog converter (Digital-to-Analog Converter, DAC), a central processing unit (Central Processing Unit, CPU), a first circulator (circulator 1, C1), a second circulator (circulator 2, C2), and a third circulator (circulator 3, C3), wherein the lengths of optical fiber A, optical fiber B, and optical fiber C are equal, optical fiber A and optical fiber B are the sensing arms of the DMZI, and optical fiber C is only responsible for guiding optical signals transmitted in the clockwise and counterclockwise directions.

[0030] PC1, PD3, ADC2, CPU, DAC, and PM form a feedback loop. The signal transmission path of the feedback loop is as follows: Figure 1As shown, the CPU analyzes the interference results output by PD3 and ADC2, and sends a compensation signal to the PM placed in the optical fiber B through the DAC. The compensation signal is mainly used to cope with the slow change of the optical fiber phase caused by changes in factors such as ambient temperature, so that the DMZI interference can be stabilized at the orthogonal bias point to obtain the highest vibration sensing sensitivity.

[0031] In order to overcome the defect in the prior art that if the feedback bandwidth is not set reasonably, the balance between system stability and event detection efficiency cannot be maintained, an embodiment of the present invention provides a feedback loop control method for a dual Mach-Zehnder interferometer, such as Figure 2 As shown, including:

[0032] Step S11: Acquire vibration signals of multiple acquisition points continuously acquired by the dual Mach-Zehnder interferometer to form a vibration signal sequence.

[0033] In an optional embodiment, vibration signals of multiple acquisition points are continuously acquired by ADC1 in DMZI to form a vibration signal sequence, wherein the vibration signal sequence may be voltage values ​​at different moments.

[0034] Step S12: Compare the peak-to-peak value of the vibration signal sequence with a preset threshold, and update the first determination value and the second determination value according to the comparison result.

[0035] In an optional embodiment, the preset threshold is a voltage slightly larger than the peak-to-peak value of the noise curve in the absence of vibration, which depends on the thermal noise, coherent Rayleigh noise and environmental noise of the system, and the specific value can be set according to actual conditions.

[0036] If it is determined that a vibration event exists according to the first determination value and the second determination value, step S13 is executed to close the feedback loop.

[0037] In the embodiment of the present invention, when it is determined that a vibration event exists, after the feedback loop is closed, the PM in the feedback loop will not generate vibration, and no matter how the feedback bandwidth is set, the PM will not affect the extraction of data related to the vibration event.

[0038] If it is determined that there is no vibration event according to the first determination value and the second determination value, step S14 is executed to start the feedback loop and adjust the phase difference in the dual Mach-Zehnder interferometer through the feedback loop.

[0039] In the embodiment of the present invention, when it is determined that there is no vibration event, the feedback loop is turned on, and the phase difference in the DMZI is adjusted through the feedback loop to ensure that the DMZI can maintain working at the orthogonal point, so that the DMZI can measure the upcoming vibration event with the highest sensitivity.

[0040] In an optional embodiment, the feedback loop may use any relevant method to adjust the phase survey in the DMZI, which is not limited in the embodiment of the present invention.

[0041] The feedback loop control method of the dual Mach-Zehnder interferometer provided by the embodiment of the present invention, after continuously collecting vibration signals of multiple collection points through DMZI to form a vibration signal sequence, the first judgment value and the second judgment value are updated according to the comparison result, and whether there is a vibration event can be determined based on the first judgment value and the second judgment value. When it is determined that there is a vibration event, the feedback loop is closed. After the feedback loop is closed, even if the vibration signal frequency falls within the feedback bandwidth, the system can obtain vibration information without interference and correctly locate. When it is determined that there is no vibration event, the feedback loop is kept in an open state, and the phase difference in the DMZI is adjusted through the feedback loop, so that the DMZI can be kept working at the orthogonal point in the standby state, so that the upcoming vibration event can be measured with the highest sensitivity. It can be seen that by implementing the present invention, the feedback operation is performed only when there is no vibration event, thereby eliminating the mutual influence between the event-induced and feedback-induced phase changes, solving the contradiction in the feedback bandwidth setting, and because the feedback is closed when the vibration event occurs, the data related to the vibration event can be directly extracted from a large amount of measurement data, which greatly simplifies the post-processing process.

[0042] In an optional embodiment, before executing the above step S11, it is necessary to debug the DMZI first: sequentially scan the voltage V driving the PM and observe the interference output to cover the phase modulation range of 2π (i.e., 1 cycle), find the maximum and minimum values ​​of the interference result, and calculate the corresponding driving voltage values ​​V respectively. max and V min . Use V Ref represents the PM drive voltage corresponding to the DMZI quadrature bias point, then V Ref =(V max +V min ) / 2.

[0043] In an alternative embodiment, if Figure 3 As shown, the above step S12 specifically includes the following steps:

[0044] If the peak-to-peak value of the vibration signal sequence is greater than a preset threshold, the first determination value is set to a first setting value, and the second determination value is set to a second setting value, wherein when the second determination value is the second setting value, it indicates that a vibration event exists.

[0045] In an optional embodiment, the first set value and the second set value may be the same value or different values. For example, when the peak-to-peak value of the vibration signal sequence is greater than a preset threshold, the first judgment value S1 and the second judgment value S2 are both set to 1. When the second judgment value is 1, it is determined that a vibration event exists.

[0046] In the embodiment of the present invention, when the peak-to-peak value V of the vibration signal sequence pp Greater than the preset threshold V th , it indicates that there must be a vibration time, such as Figure 4 As shown in the rightmost box in the figure, at this time, the second determination value is set to a second set value that can indicate the presence of a vibration event.

[0047] In an optional embodiment, the vibration signal is obtained by periodically collecting the vibration signal by DMZI, and continuously collecting signals of multiple collection points in each cycle, wherein each cycle corresponds to a vibration signal sequence, such as Figure 3 As shown, the above step S12 specifically includes the following steps:

[0048] If the peak-to-peak value of the vibration signal sequence is less than or equal to the preset threshold, the first determination value is set to the third set value.

[0049] If the first determination values ​​in the adjacent first M cycles of the current cycle are all the third set value, the second determination value is set to the fourth set value, wherein when the second determination value is the fourth set value, it indicates that there is no vibration event.

[0050] If the first determination value of at least one cycle in the first M adjacent cycles of the current cycle is the first set value, the second determination value is set to the second set value, wherein when the second determination value is the second set value, it indicates that a vibration event exists.

[0051] In the embodiment of the present invention, when the peak-to-peak value of the vibration signal sequence is less than or equal to the preset threshold, it is not possible to directly determine whether there is a vibration event based on the vibration signal of the current cycle, such as Figure 4 As shown, in Figure 4 In the leftmost box, the peak-to-peak value of the vibration signal sequence is less than or equal to the preset threshold, and there is no vibration event at this time, but Figure 4 In the middle box, although the peak-to-peak value of the vibration signal is also less than or equal to the preset threshold, a vibration event exists at this time. Therefore, when the peak-to-peak value of the vibration signal sequence is less than or equal to the preset threshold, the second judgment value cannot be directly assigned, and the second judgment value needs to be determined based on the historical value of the first judgment value.

[0052] In an optional embodiment, the value of M can be set according to actual needs. For example, when the value of M is 3, it means that when the first judgment value is the first set value in three consecutive periods, the second judgment value is set to the second set value. The first judgment value is the first set value in three consecutive periods, indicating that the peak-to-peak value of the vibration signal sequence for three consecutive periods is greater than the preset threshold. At this time, the second judgment value can be determined as the second set value, and it is determined that a vibration event currently exists. However, when there is a vibration signal sequence with a peak-to-peak value less than or equal to the preset threshold in the vibration signal sequence for three consecutive periods, it indicates that the possibility of vibration caused by interference is greater than the occurrence of a vibration event. At this time, the second judgment value is determined as the fourth set value.

[0053] Exemplarily, the first set value and the second set value are determined to be 1, and the third set value and the fourth set value are determined to be 0. When the peak-to-peak value of the vibration signal sequence is greater than the preset threshold, the first judgment value S1 and the second judgment value S2 are both determined to be 1. When the peak-to-peak value of the vibration signal sequence is less than or equal to the preset threshold, S1 is determined to be 0. If S1 is 0 in multiple consecutive cycles, S2 is determined to be 0, otherwise S2 is determined to be 1. When S2 is 1, it indicates that a vibration event exists, and the feedback loop is closed at this time. When S2 is 0, it indicates that there is no vibration event, and the feedback loop is opened at this time.

[0054] In an optional embodiment, in the feedback loop control method of the dual Mach-Zehnder interferometer provided in the embodiment of the present invention, the vibration signal sequence is continuously collected by the dual Mach-Zehnder interferometer N 2 The data sampling interval of the dual Mach-Zehnder interferometer is shorter than the feedback interval of the feedback loop by N. 2 times.

[0055] The method provided in the embodiment of the present invention is only higher than the traditional feedback method. 2 The contradiction in feedback bandwidth setting can be solved at the cost of doubling the sampling rate (not the feedback speed), and the feedback loop will not interfere with the vibration signal of the vibration event.

[0056] In an optional embodiment, after determining that a vibration event exists and closing the feedback loop, the vibration event position information is determined based on the vibration signal sequence.

[0057] In an embodiment of the present invention, only when the second judgment value is the second set value, the vibration event information is determined according to the vibration signal sequence corresponding to the second judgment value, and there is no need to process other vibration signals. That is, the embodiment of the present invention does not need to use complex algorithms to extract event-related data, thereby simplifying the post-processing process.

[0058] In an optional embodiment, the method provided in the embodiment of the present invention does not use all vibration-related data for post-processing, but specifically selects an appropriate data segment from the beginning of the vibration, whose duration is short enough to ignore the environmental impact, and long enough to include enough vibration cycles to accurately locate the event. In the specific implementation process, the higher the vibration signal frequency and the environmental noise frequency, the shorter the required data segment duration.

[0059] The embodiment of the present invention provides a feedback loop control device for a dual Mach-Zehnder interferometer, such as Figure 5 As shown, including:

[0060] The data acquisition module 21 is used to obtain vibration signals of multiple acquisition points continuously acquired by the dual Mach-Zehnder interferometer to form a vibration signal sequence. For details, please refer to the description of step S11 in the above embodiment, which will not be repeated here.

[0061] The comparison module 22 is used to compare the peak-to-peak value of the vibration signal sequence with a preset threshold value, and update the first determination value and the second determination value according to the comparison result. For details, please refer to the description of step S12 in the above embodiment, which will not be repeated here.

[0062] The feedback loop control module 23, if it is determined that a vibration event exists according to the first judgment value and the second judgment value, the loop control module is used to close the feedback loop; if it is determined that no vibration event exists according to the first judgment value and the second judgment value, the loop control module is used to open the feedback loop, and adjust the phase difference in the dual Mach-Zehnder interferometer through the feedback loop. For details, please refer to the description of step S13 and step S14 in the above embodiment, which will not be repeated here.

[0063] In an optional embodiment, in the feedback loop control device of the dual Mach-Zehnder interferometer provided in the embodiment of the present invention, the dual Mach-Zehnder interferometer periodically collects vibration signals, continuously collects vibration signals of multiple collection points in each cycle, and each cycle corresponds to a vibration signal sequence. The comparison module 22 includes:

[0064] A comparison submodule, used for comparing the peak-to-peak value of the vibration signal sequence with a preset threshold;

[0065] The first assignment submodule is used to set the first determination value to a third set value if the peak-to-peak value of the vibration signal sequence is less than or equal to a preset threshold. For details, please refer to the description in the above method embodiment, which will not be repeated here.

[0066] The second assignment submodule is used to set the second judgment value to the fourth setting value if the first judgment values ​​in the adjacent first M cycles of the current cycle are all the third setting values. When the second judgment value is the fourth setting value, it indicates that there is no vibration event. For details, please refer to the description in the above method embodiment, which will not be repeated here.

[0067] An embodiment of the present invention provides a computer device, such as Figure 6 As shown, the computer device mainly includes one or more processors 31 and a memory 32. Figure 6 A processor 31 is taken as an example.

[0068] The computer device may further include: an input device 33 and an output device 34 .

[0069] The processor 31, the memory 32, the input device 33 and the output device 34 may be connected via a bus or other means. Figure 6 The example of connecting through bus is taken in the following.

[0070] The processor 31 may be a central processing unit (CPU). The processor 31 may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, or a combination of the above chips. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc. The memory 32 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the feedback loop control device of the dual Mach-Zehnder interferometer, etc. In addition, the memory 32 may include a high-speed random access memory, and may also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 32 may optionally include a memory remotely arranged relative to the processor 31, and these remote memories may be connected to the feedback loop control device of the dual Mach-Zehnder interferometer via a network. The input device 33 can receive a calculation request (or other digital or character information) input by a user, and generate a key signal input related to the feedback loop control device of the dual Mach-Zehnder interferometer. The output device 34 can include a display device such as a display screen to output the calculation result.

[0071] An embodiment of the present invention provides a computer-readable storage medium, which stores computer instructions, and the computer storage medium stores computer executable instructions, which can execute the feedback loop control method of the dual Mach-Zehnder interferometer in any of the above method embodiments. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above types of memory.

[0072] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A feedback loop control method for a dual Mach-Zehnder interferometer, characterized in that: include: Acquire vibration signals of multiple acquisition points continuously acquired by a dual Mach-Zehnder interferometer to form a vibration signal sequence; Comparing the peak-to-peak value of the vibration signal sequence with a preset threshold, and updating the first determination value and the second determination value according to the comparison result; If it is determined that a vibration event exists according to the first determination value and the second determination value, closing the feedback loop; If it is determined that there is no vibration event according to the first determination value and the second determination value, the feedback loop is started, and the phase difference in the dual Mach-Zehnder interferometer is adjusted through the feedback loop; The vibration signal is obtained by the dual Mach-Zehnder interferometer periodically collecting signals from multiple collection points in each cycle, wherein each cycle corresponds to a vibration signal sequence; The step of comparing the peak-to-peak value of the vibration signal sequence with a preset threshold value and updating the first determination value and the second determination value according to the comparison result comprises: If the peak-to-peak value of the vibration signal sequence is less than or equal to the preset threshold, setting the first determination value to a third set value; If the first determination values ​​in the first M adjacent cycles of the current cycle are all the third set value, the second determination value is set to the fourth set value, wherein when the second determination value is the fourth set value, it indicates that there is no vibration event; The step of comparing the peak-to-peak value of the vibration signal sequence with a preset threshold value and updating the first determination value and the second determination value according to the comparison result comprises: The peak-to-peak value of the vibration signal sequence is compared with a preset threshold. If the peak-to-peak value of the vibration signal sequence is greater than the preset threshold, the first judgment value is set to a first setting value, and the second judgment value is set to a second setting value. When the second judgment value is the second setting value, it indicates the presence of a vibration event.

2. The feedback loop control method of a dual Mach-Zehnder interferometer according to claim 1, characterized in that: Also includes: If the first determination value of at least one cycle in the first M adjacent cycles of the current cycle is the first set value, the second determination value is set to the second set value, wherein when the second determination value is the second set value, it indicates the presence of a vibration event.

3. The feedback loop control method of a dual Mach-Zehnder interferometer according to claim 1, characterized in that: The vibration signal sequence is obtained by continuously collecting vibration signals of N2 collection points by the dual Mach-Zehnder interferometer, and the data sampling interval of the dual Mach-Zehnder interferometer is N2 times shorter than the feedback interval of the feedback loop.

4. The feedback loop control method of a dual Mach-Zehnder interferometer according to claim 1, characterized in that: If it is determined that a vibration event exists according to the first determination value and the second determination value, then after the step of closing the feedback loop, the method further includes: Vibration event position information is determined according to the vibration signal sequence.

5. A feedback loop control device for a dual Mach-Zehnder interferometer, characterized in that: include: A data acquisition module is used to acquire vibration signals of multiple acquisition points continuously acquired by a dual Mach-Zehnder interferometer to form a vibration signal sequence; A comparison module, used for comparing the peak-to-peak value of the vibration signal sequence with a preset threshold value, and updating the first determination value and the second determination value according to the comparison result; A feedback loop control module, wherein if it is determined that a vibration event exists according to the first determination value and the second determination value, the loop control module is used to close the feedback loop; if it is determined that no vibration event exists according to the first determination value and the second determination value, the loop control module is used to open the feedback loop, and adjust the phase difference in the dual Mach-Zehnder interferometer through the feedback loop; The dual Mach-Zehnder interferometer periodically collects vibration signals, continuously collects vibration signals of multiple collection points in each cycle, and each cycle corresponds to a vibration signal sequence. The comparison module includes: A comparison submodule, used for comparing the peak-to-peak value of the vibration signal sequence with a preset threshold; a first assignment submodule, wherein if the peak-to-peak value of the vibration signal sequence is less than or equal to a preset threshold, the first assignment submodule is used to set the first determination value to a third set value; A second value assignment submodule, if the first determination values ​​in the adjacent first M cycles of the current cycle are all the third set value, then the second value assignment submodule is used to set the second determination value to a fourth set value, wherein when the second determination value is the fourth set value, it indicates that there is no vibration event; The comparison module is also used to compare the peak-to-peak value of the vibration signal sequence with a preset threshold; if the peak-to-peak value of the vibration signal sequence is greater than the preset threshold, the first judgment value is set to a first setting value, and the second judgment value is set to a second setting value; wherein, when the second judgment value is the second setting value, it indicates the presence of a vibration event.

6. A computer device, characterized in that: include: at least one processor; And a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to execute the feedback loop control method of the dual Mach-Zehnder interferometer as described in any one of claims 1-4.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the feedback loop control method of the dual Mach-Zehnder interferometer according to any one of claims 1 to 4.

Images