CN114518162B - Optical fiber hydrophone interference signal intensity compensation method and system - Google Patents

Abstract

The application discloses a method and a system for compensating interference signal intensity of an optical fiber hydrophone, wherein the method comprises the following steps: acquiring an echo pulse signal, and processing the echo pulse signal by using a preset method to obtain an initial interference signal; calculating an intensity attenuation coefficient of the initial interference signal; and performing intensity compensation on the initial interference signal according to the intensity attenuation coefficient to obtain an interference signal after intensity compensation. The method resamples the distorted echo pulse signals by using a preset method, so that the track of each pulse peak value can be positioned more accurately; determining a signal intensity attenuation coefficient by calculating the peak value of the pulse signal; and performing intensity compensation on the signal according to the intensity attenuation coefficient. The invention fundamentally solves the problem of amplitude attenuation of interference signals caused by introducing the circulator, effectively improves the signal-to-noise ratio of the interference signals and improves the stability of signal demodulation.

Description

A method and system for compensating the interference signal strength of an optical fiber hydrophone

technical field

The invention relates to the technical field of optical fiber sensing, in particular to a method, device, computer-readable storage medium and system for compensating the interference signal strength of an optical fiber hydrophone.

Background technique

Optical fiber sensors have been extensively studied worldwide due to their advantages of high sensitivity, anti-electromagnetic interference, and large-scale multiplexing. In recent years, with the mature application of drawing tower online grating technology, the weak reflection grating sensor array has been vigorously developed, and the multiplexing ability of the grating has been greatly enhanced. In the field of underwater environment detection, large-scale multiplexing and good resolution are the key indicators of fiber optic hydrophones, especially for towed arrays, the increase of array multiplexing primitives can increase the array gain, thereby expanding the detection range of targets ; At the same time, good spatial resolution can further improve detection accuracy.

In order to realize the high spatial resolution of the quasi-distributed TDM array, reducing the grating interval and increasing the sampling rate of the system have become the preferred solutions. Improving the detection accuracy of weak light pulses and selecting a stable interference signal demodulation algorithm have an important impact on system performance. In the prior art, the demodulation algorithm based on the 3×3 coupler has been widely used because of its simple structure; however, in the optical path where this algorithm is applied, due to the insertion loss of the circulator, the light intensity of one of the signals will be reduced, and at the same time, Due to the extension of the optical path, the timing of the three optical pulses arriving at the detector is not consistent, which is very likely to cause the position of the peak point to shift. Recording the wrong movement track of the peak after the offset will greatly reduce the intensity of the interference signal and increase the three-way signal. of asymmetry. The phase-shift demodulation technology based on Ellipse Fitting Algorithm (EFA) has high precision and stability for measuring such asymmetric signals, but the complexity of this algorithm is high, especially for time-division multiplexing systems, generally A high-speed data acquisition system is required to process massive amounts of data, and the application of this method will also increase the burden of data processing, which is not conducive to application and promotion.

Therefore, it is necessary to provide a simple and effective signal preprocessing method to solve the problem of interference signal amplitude attenuation caused by the introduction of a single-channel circulator. At the same time, it is necessary to improve the stability of the interference signal output and the signal-to-noise ratio of the signal. Subsequent signal demodulation is provided for convenience.

Contents of the invention

In view of this, it is necessary to provide a fiber optic hydrophone interference signal strength compensation method, device, computer-readable storage medium and system to solve the interference signal amplitude attenuation, signal The problem of low signal-to-noise ratio and poor demodulation stability.

In order to solve the above problems, the present invention provides a method for compensating the interference signal strength of an optical fiber hydrophone, comprising:

acquiring an echo pulse signal, and processing the echo pulse signal by a preset method to obtain an initial interference signal;

calculating an intensity attenuation coefficient of the initial interference signal;

Perform intensity compensation on the initial interference signal according to the intensity attenuation coefficient to obtain an intensity-compensated interference signal.

Further, the preset method is a cubic spline interpolation algorithm.

Further, the echo pulse signal is processed by a preset method to obtain an initial interference signal, including:

Inputting several interpolation nodes at equal intervals within the preset interval of the echo pulse signal;

respectively substituting the interpolation nodes into preset cubic spline interpolation functions to obtain the cubic spline interpolation function values corresponding to the interpolation nodes;

The cubic spline interpolation function value corresponding to the interpolation node is determined as the echo pulse data corresponding to the interpolation node.

Further, the echo pulse signal and the initial interference signal are three-way signals.

Further, obtaining the echo pulse signal includes:

The echo pulse signal after interference generated by the sensing arm and the reference arm through the coupler is obtained.

Further, the three initial interference signals specifically include:

where E _m represents the amplitude of the sensing arm, E _k represents the amplitude of the reference arm, represents the phase change measured due to an external shock, /> represents the constant of the initial phase, and a and b represent the coefficient of variation of the signal peak intensity, respectively.

Further, calculating the intensity attenuation coefficient of the initial interference signal includes:

Obtaining the first peak-to-peak value according to the intensity maximum value and the intensity minimum value of the first interference signal;

Obtaining the second peak-to-peak value according to the intensity maximum value and the intensity minimum value of the second interference signal;

An intensity attenuation coefficient is calculated according to the first peak-to-peak value and the second peak-to-peak value.

The present invention also provides a fiber optic hydrophone interference signal strength compensation device, including a processor and a memory, and a computer program is stored in the memory, and when the computer program is executed by the processor, any of the above-mentioned technical solutions can be realized A method for compensating the interference signal strength of an optical fiber hydrophone.

The present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, a kind of optical fiber hydrophone interference signal strength compensation as described in any of the above technical solutions is realized. method.

The present invention also provides a fiber optic hydrophone interference signal strength compensation system, which includes the fiber optic hydrophone interference signal strength compensation device, and also includes a light source, a signal generator, an acousto-optic modulator, an erbium-doped fiber amplifier, a first optical fiber Circulator, weak reflection grating sensor array, second circulator, 3×3 coupler, Faraday rotating mirror, demodulator;

The narrow-linewidth continuous light emitted by the light source enters the acousto-optic modulator driven by the signal generator and is modulated into pulsed light;

After the pulsed light is amplified by the erbium-doped fiber amplifier, it enters the weak reflection grating sensing array through the first optical fiber circulator;

The pulse sequence reflected back by the weak reflection grating sensor array passes through the second optical fiber circulator, enters the 3×3 coupler, and then passes through the Faraday rotating mirror to obtain the echo pulse signal;

The echo pulse signal enters a 3×3 coupler, and is processed by the optical fiber hydrophone interference signal strength compensation device to obtain a compensated interference signal;

The compensated interference signal enters the demodulator for demodulation processing.

Compared with the prior art, the beneficial effects of the present invention include: firstly, acquiring the echo pulse signal, processing the echo pulse signal with a preset method to obtain an initial interference signal; secondly, calculating the initial interference signal an intensity attenuation coefficient; finally, performing intensity compensation on the initial interference signal according to the intensity attenuation coefficient to obtain an intensity-compensated interference signal. The present invention uses a preset method to resample the distorted echo pulse signal, fits the echo pulse signal, and can more accurately locate the trajectory of each pulse peak value; by calculating the peak value of the pulse signal, the signal strength attenuation is determined Coefficient, the signal intensity is compensated according to the intensity attenuation coefficient. The invention fundamentally solves the problem of amplitude attenuation of the interference signal caused by the introduction of the circulator, effectively improves the signal-to-noise ratio of the interference signal, and improves the stability of signal demodulation.

Description of drawings

Fig. 1 is a schematic flow chart of an embodiment of an optical fiber hydrophone interference signal strength compensation method provided by the present invention;

Fig. 2 is a structural schematic diagram of an embodiment of an optical fiber hydrophone interference signal strength compensation system provided by the present invention;

Fig. 3 is a principle schematic diagram of an embodiment of an optical fiber hydrophone interference signal strength compensation system provided by the present invention;

Fig. 4 is a kind of fiber optic hydrophone interference signal intensity compensation system one embodiment provided by the present invention The weak reflection grating sensor array is the waveform diagram of the original echo pulse signal of 800 weak reflection fiber grating sensor arrays;

Fig. 5 is a waveform comparison diagram of an echo pulse signal and an initial interference signal of an embodiment of an optical fiber hydrophone interference signal strength compensation system provided by the present invention;

6 is a schematic diagram of an actual experiment of an embodiment of an optical fiber hydrophone interference signal strength compensation method provided by the present invention;

Fig. 7 is a schematic diagram of 10 Hz demodulated signals obtained by using three different methods in an embodiment of a method for compensating the interference signal strength of an optical fiber hydrophone provided by the present invention.

Detailed ways

Preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the application and together with the embodiments of the present invention are used to explain the principle of the present invention and are not intended to limit the scope of the present invention.

The present invention provides a fiber optic hydrophone interference signal strength compensation method, device, computer-readable storage medium and system, which will be described in detail below.

An embodiment of the present invention provides a method for compensating the interference signal strength of an optical fiber hydrophone, the schematic flow chart of which is shown in Figure 1, specifically including:

Step S101, acquiring an echo pulse signal, and processing the echo pulse signal by a preset method to obtain an initial interference signal;

Step S102, calculating the intensity attenuation coefficient of the initial interference signal;

Step S103 , performing intensity compensation on the initial interference signal according to the intensity attenuation coefficient to obtain an intensity-compensated interference signal.

Compared with the prior art, this embodiment provides a fiber optic hydrophone interference signal strength compensation method. First, the echo pulse signal is obtained, and the echo pulse signal is processed by a preset method to obtain an initial interference signal ; secondly, calculating the intensity attenuation coefficient of the initial interference signal; finally, performing intensity compensation on the initial interference signal according to the intensity attenuation coefficient to obtain an intensity-compensated interference signal. The present invention uses a preset method to resample the distorted echo pulse signal, thereby fitting the echo pulse signal, and can more accurately locate the trajectory of each pulse peak value; by calculating the peak value of the pulse signal, the signal can be determined Intensity attenuation coefficient, according to the intensity attenuation coefficient to compensate the signal strength. The invention fundamentally solves the problem of amplitude attenuation of the interference signal caused by the introduction of the circulator, effectively improves the signal-to-noise ratio of the interference signal, and improves the stability of signal demodulation.

As a preferred embodiment, in step S101, the preset method is a cubic spline interpolation algorithm.

As a preferred embodiment, the echo pulse signal is processed by a preset method to obtain an initial interference signal, including:

Inputting several interpolation nodes at equal intervals within the preset interval of the echo pulse signal;

respectively substituting the interpolation nodes into preset cubic spline interpolation functions to obtain the cubic spline interpolation function values corresponding to the interpolation nodes;

The cubic spline interpolation function value corresponding to the interpolation node is determined as the echo pulse data corresponding to the interpolation node.

Since no research shows that the echo pulse signal can be described by a fixed mathematical expression, in order to reduce the noise of the echo pulse signal, a cubic spline interpolation method is introduced to process the echo pulse signal. For the echo pulse signal, insert n+1 discrete sampling points equidistantly on the interval [p, q], and interpolate the original echo pulse signal by constructing the cubic polynomial function s(x) of the interval;

Assuming s"( _xi )=M _i (i=0,1,...,n), s'(xi ₎ =m _i (i=0,1,...,n) is valid, we can use the existing Known conditions are used to solve the function value of the above function, and the three types of boundary conditions can be expressed as:

Among them, s'(g) and s"(g) represent the first derivative and second derivative of the polynomial function respectively. It can be seen that the cubic spline interpolation algorithm can dynamically fit the echo pulse signal, which is used to process optical fiber hydrophone The echo pulse signal of the device system.

As a preferred embodiment, both the echo pulse signal and the initial interference signal are three-way signals.

As a preferred embodiment, obtaining the echo pulse signal includes:

The echo pulse signal after interference generated by the sensing arm and the reference arm through the coupler is obtained.

As a preferred embodiment, the initial interference signal specifically includes:

where E _m represents the amplitude of the sensing arm, E _k represents the amplitude of the reference arm, represents the phase change measured due to an external shock, /> represents the constant of the initial phase, and a and b represent the coefficient of variation of the signal peak intensity, respectively.

As a preferred embodiment, in step S102, calculating the intensity attenuation coefficient of the initial interference signal includes:

Obtaining the first peak-to-peak value according to the intensity maximum value and the intensity minimum value of the first interference signal;

Obtaining the second peak-to-peak value according to the intensity maximum value and the intensity minimum value of the second interference signal;

An intensity attenuation coefficient is calculated according to the first peak-to-peak value and the second peak-to-peak value.

As a specific embodiment, since each pulse in the echo pulse signal represents a grating sensor, the echo pulse signal needs to be segmented according to the sensing distance. For the pulse corresponding to any grating sensor, the echo pulse signal generated by the grating sensor can be recorded, and a fixed pulse delay can be used to obtain the change track of the peak value of the pulse signal. For the three initial interference signals obtained through the 3×3 coupler:

when When , the signal strength of the first interference signal I _C-1 is the largest, so the maximum signal strength of the first interference signal is expressed as:

when When , the signal strength of the first interference signal I _C-1 is the smallest, so the minimum signal strength of the first interference signal is expressed as:

From this, it can be obtained that the first peak-to-peak value (vpp) of the first interference signal I _C-1 is:

(I _C-1 ) _max -(I _C-1 ) _min ＝4aE _m E _k

By the same method, the second peak-to-peak value of the second interference signal _IC-2 can be obtained as:

(I _C-2 ) _max -(I _C-2 ) _min ＝4bE _m E _k

From this, the attenuation coefficient of the interference signal strength caused by the pulse delay can be calculated as:

As a specific embodiment, in step S103, according to the intensity attenuation coefficient, the intensity compensation is performed on the initial interference signal to obtain the intensity-compensated interference signal, including:

For the intensity attenuation coefficient The initial interference signal:

The method of performing intensity compensation on the initial interference signal is: divide the signal peak intensity variation coefficient by the intensity attenuation coefficient to compensate the signal intensity attenuation generated by the echo pulse signal passing through the circulator, which can be expressed as:

As a specific embodiment, a demodulation algorithm based on a 3*3 coupler is used to obtain the processing result of the underwater acoustic signal.

An embodiment of the present invention provides a fiber optic hydrophone interference signal strength compensation device, including a processor and a memory, and a computer program is stored in the memory, and when the computer program is executed by the processor, any of the above-mentioned A method for compensating the interference signal strength of an optical fiber hydrophone described in the technical solution.

An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, a fiber optic hydrophone interference signal as described in any of the above technical solutions is realized. Intensity Compensation Method.

According to the computer-readable storage medium and device provided by the above-mentioned embodiments of the present invention, it can be implemented with reference to the specific description of the method for compensating the interference signal strength of an optical fiber hydrophone as described above according to the present invention, and has the same characteristics as described above A fiber optic hydrophone interference signal strength compensation method has similar beneficial effects and will not be repeated here.

An embodiment of the present invention provides a fiber optic hydrophone interference signal strength compensation system, as shown in Figure 2, Figure 2 is a schematic structural diagram of the fiber optic hydrophone interference signal strength compensation system, the system includes the fiber optic hydrophone The hearing instrument interference signal strength compensation device also includes a light source, a signal generator, an acousto-optic modulator, an erbium-doped fiber amplifier, a first optical fiber circulator, a weak reflection grating sensing array, a second circulator, a 3×3 coupler, Faraday rotating mirror, demodulator;

The narrow-linewidth continuous light emitted by the light source enters the acousto-optic modulator driven by the signal generator and is modulated into pulsed light;

After the pulsed light is amplified by the erbium-doped fiber amplifier, it enters the weak reflection grating sensing array through the first optical fiber circulator;

The pulse sequence reflected back by the weak reflection grating sensor array passes through the second optical fiber circulator, enters the 3×3 coupler, and then passes through the Faraday rotating mirror to obtain the echo pulse signal;

The echo pulse signal enters a 3×3 coupler, and is processed by the optical fiber hydrophone interference signal strength compensation device to obtain a compensated interference signal;

The compensated interference signal enters the demodulator for demodulation processing.

As a specific embodiment, the Faraday rotating mirror includes a first Faraday rotating mirror and a second Faraday rotating mirror whose arm length difference is equal to the pitch of the grating.

As a specific embodiment, as shown in Fig. 3, Fig. 3 is a schematic diagram of the principle of the optical fiber hydrophone interference signal strength compensation system in this embodiment, and the weak reflection grating sensing array in the system is an uwFBGs array. The echo pulse signal passing through the 3×3 coupler is divided into three signals of C-1, C-2 and C-3. In order to meet the conditions of the 3×3 demodulation algorithm, the second optical fiber circulator is usually used to transmit C -1 way signal. In the specific analysis, the echo pulse signal and the initial interference signal are shown in the dotted line diagram. After passing through the second optical fiber circulator, the pulse of the C-1 signal has a delay compared with the C-2 signal and the C-3 signal. In this case, the peak-to-peak amplitudes of the three interference signals obtained by fixing the abscissa will be different. The strength of the three-way signal of C-1, C-2 and C-3 can be expressed as:

where E _m represents the amplitude of the sensing arm, E _k represents the amplitude of the reference arm, represents the phase change measured due to an external shock, /> represents the constant of the initial phase, and a and b represent the coefficient of variation of the signal peak intensity, respectively.

Example 1

As a specific embodiment, in order to meet the interference conditions in the optical fiber hydrophone interference signal intensity compensation system, the light source is a narrow linewidth laser (DFB-M-1550-150-F-10-09MPF-FC/APC) , the bandwidth of the laser is 3kHz, and the center wavelength is 1550nm;

The acousto-optic modulator (T-M200-0.1C2J-3-F2S) generates a pulse period of 2kHz and a pulse width of 20ns;

The echo pulse signal through the 3×3 coupler is divided into three signals: C-2 signal and C-3 signal directly enter the optical fiber hydrophone interference signal strength compensation device, and C-1 signal passes through the second ring The sensor then enters the optical fiber hydrophone interference signal strength compensation device.

The detection bandwidth of the interference signal strength compensation device (KG-200M-APR) is 200MHz. In order to distinguish each narrow pulse of the sensor, the sampling rate of the processor is set to 250MSa/s.

In this embodiment, the weak reflection grating sensor array is a uwFBG TDM array with 800 grating sensors, and its sensing distance is 4km. As shown in Figure 4, the abscissa in the figure is the distance of the sensor, and the ordinate is the amplitude of the echo pulse signal. By amplifying part of the echo pulse signal, it can be seen that: For example, the total offset of the C-1 signal is t ₀ , therefore, the amplitude of the C-1 signal at the same position will be greatly reduced during interference, which verifies the above theoretical analysis.

After the echo pulse signal enters the optical fiber hydrophone interference signal strength compensation device, cubic spline interpolation is first used to fit the echo pulse signal to reduce the strong noise in the echo pulse signal. The echo pulse signal and the initial interference signal obtained after interpolation of the echo pulse signal are shown in FIG. 5 . In Figure 5, (a) is the original echo pulse signal, (b) is the initial interference signal; in (a) and (b), the abscissa is the time, and the ordinate is the amplitude value, which can be seen intuitively from the figure , compared with the echo pulse signal, the initial interference signal obtained after cubic spline interpolation processing is relatively complete, which proves that the cubic spline interpolation algorithm is suitable for processing the pulse signal of weak reflection fiber grating.

Example 2

As a specific embodiment, as shown in FIG. 6, FIG. 6 is a schematic diagram of an actual experiment of an optical fiber hydrophone interference signal strength compensation system; this embodiment adopts the vibration liquid column method to simulate and generate underwater sound waves. The sound pressure field in the liquid column is generated by an excitation table with a linear power amplifier (VT500), and the voltage sensitivity of the accelerometer is 5.76pc/m·s ^-2 . Limited by the output power, the exciter can only generate a large amplitude at low frequency. Therefore, in order to meet the requirement of generating a phase change greater than π amplitude, the underwater acoustic signal in the low frequency range of 5-50 Hz is selected for the experiment. At the same time, in order to obtain the correct standing wave signal, the inner diameter of the circular tube is set to 7.50cm, and the height of the liquid column is set to 18.75cm. The fiber optic hydrophone in the experimental system uses a uwFBGs array with a center wavelength of 1550nm and a reflectivity between -40dB and -50dB. The distance between adjacent gratings is 5m. The data collector uses NI PXIe 5170R, using data processing The detector performs preprocessing of cubic spline interpolation and intensity compensation on the acquired signal.

Example 3

In this embodiment, three different methods are used to obtain the 10 Hz demodulated signal, and the power spectral density (PSD) is calculated, hereinafter referred to as PSD. The experimental results are shown in Figure 7, in which the abscissa of each waveform is the frequency, and the ordinate is the demodulated signal amplitude value. In Figure 7, the upper waveform represents the demodulation result obtained from the echo pulse signal without interpolation and intensity compensation processing, and the middle waveform represents the demodulation result obtained by directly applying intensity compensation to the echo pulse signal without interpolation , the lower waveform represents the result of demodulation of the echo pulse signal after cubic spline interpolation and intensity compensation; the signal-to-noise ratios obtained by the three methods are 10.75dB, 23.21dB and 23.31dB, respectively.

It can be seen that the signal-to-noise ratio of the signal without any processing is low, and the attenuation of the interference signal caused by the pulse delay is the main factor causing the signal distortion. After the intensity compensation is performed by the method of the technical solution, the demodulation effect is obviously improved.

On the other hand, the present embodiment analyzes the average values of the noise PSD when the reference signal is 1 rad, and they are -36.14dB, -45.06dB and -46.17dB respectively. It can be seen that after cubic spline interpolation, the noise PSD average value can be reduced by 1.11dB; after intensity compensation, the suppression of noise can be further increased by about 8.92dB, which also proves that the method for dealing with the pulse delay problem proposed by this application is very effective.

In addition, as shown in Table 1, in this embodiment, demodulation experiments of different frequencies were carried out on underwater acoustic signals of 5 Hz, 10 Hz, 20 Hz, 30 Hz, 40 Hz and 50 Hz, and the qualitative analysis results are shown in Table 1. It can be seen that after cubic spline interpolation and intensity compensation, the average PSD of the signal is greatly improved, and the gain is greater than 7dB, which verifies the robustness of the method of the present invention under different frequencies. Table 1 records the original and corrected PSD results at different frequencies.

Table 1

The invention discloses a method, a device, a computer-readable storage medium and a system for compensating the interference signal strength of an optical fiber hydrophone. First, the echo pulse signal is obtained, and the echo pulse signal is processed by a preset method to obtain an initial interference signal; secondly, an intensity attenuation coefficient is calculated according to the initial interference signal; finally, an intensity attenuation coefficient is obtained according to the intensity attenuation coefficient , performing intensity compensation on the initial interference signal to obtain an intensity-compensated interference signal.

The present invention uses a preset method to resample the distorted echo pulse signal, thereby fitting the echo pulse signal, and can more accurately locate the trajectory of each pulse peak value; by calculating the peak value of the pulse signal, the signal can be determined Intensity attenuation coefficient, according to the intensity attenuation coefficient to compensate the signal intensity. The invention fundamentally solves the problem of amplitude attenuation of the interference signal caused by the introduction of the circulator, effectively improves the signal-to-noise ratio of the interference signal, and improves the stability of signal demodulation. It can be seen from various experimental results that the present invention has a good effect on dealing with the pulse delay problem, and the demodulation stability is obviously improved; it also has good robustness and good practicability, and is suitable for wide-scale popularization and use.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention.

Claims (7)

1. The optical fiber hydrophone interference signal intensity compensation method is characterized by comprising the following steps:

acquiring an echo pulse signal, and processing the echo pulse signal by using a preset method to obtain an initial interference signal;

calculating an intensity attenuation coefficient of the initial interference signal;

performing intensity compensation on the initial interference signal according to the intensity attenuation coefficient to obtain an interference signal after intensity compensation;

the echo pulse signal and the initial interference signal are three signals;

the three paths of initial interference signals specifically comprise:

wherein ,representing the first path of interference signal->Representing the second path of interference signal, ">Representing a third path of the interference signal,E _m representing the amplitude of the sensing arm,E _k the amplitude of the reference arm is indicated,φ _s (t) Indicating the phase change measured due to external impact,φ ₀ a constant representing the initial phase is provided,aandbrespectively representing the signal peak intensity change coefficients;

calculating an intensity attenuation coefficient of the initial interference signal, comprising:

obtaining a first peak-to-peak value according to the difference value between the maximum intensity value and the minimum intensity value of the first path of interference signals;

obtaining a second peak-to-peak value according to the difference value between the maximum intensity value and the minimum intensity value of the second path of interference signals;

and calculating to obtain an intensity attenuation coefficient according to the ratio of the first peak value to the second peak value.

2. The method for compensating for the interference signal strength of an optical fiber hydrophone according to claim 1, wherein the preset method is a cubic spline interpolation algorithm.

3. The method for compensating the interference signal intensity of the optical fiber hydrophone according to claim 2, wherein the echo pulse signal is processed by a preset method to obtain an initial interference signal, comprising:

inputting a plurality of interpolation nodes at equal intervals in a preset interval of the echo pulse signal;

substituting the interpolation nodes into a preset cubic spline interpolation function respectively to obtain a cubic spline interpolation function value corresponding to the interpolation nodes;

and determining the cubic spline interpolation function value corresponding to the interpolation node as echo pulse data corresponding to the interpolation node.

4. The method of compensating for the intensity of an interference signal of a fiber optic hydrophone as recited in claim 1, wherein acquiring the echo pulse signal comprises:

and acquiring echo pulse signals generated by the sensor arm and the reference arm after interference through the coupler.

5. An optical fiber hydrophone interference signal strength compensation device, comprising a processor and a memory, wherein the memory stores a computer program, which when executed by the processor, implements the optical fiber hydrophone interference signal strength compensation method according to any one of claims 1-4.

6. A computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements a method of optical fiber hydrophone interference signal strength compensation according to any of the claims 1-4.

7. An optical fiber hydrophone interference signal intensity compensation system is characterized by comprising the optical fiber hydrophone interference signal intensity compensation device according to claim 5, and further comprising a light source, a signal generator, an acousto-optic modulator, an erbium-doped optical fiber amplifier, a first optical fiber circulator, a weak reflection grating sensing array, a second circulator, a 3×3 coupler, a Faraday rotating mirror and a demodulator;

the narrow linewidth continuous light emitted by the light source enters an acousto-optic modulator driven by a signal generator to modulate Cheng Maichong light;

the pulse light enters the weak reflection grating sensing array through the first optical fiber circulator after being amplified by the erbium-doped optical fiber amplifier;

the pulse sequence reflected by the weak reflection grating sensing array enters a 3 multiplied by 3 coupler through a second optical fiber circulator and then passes through a Faraday rotating mirror to obtain an echo pulse signal;

the echo pulse signals enter a 3 multiplied by 3 coupler and are processed by the optical fiber hydrophone interference signal intensity compensation device to obtain compensated interference signals;

and the compensated interference signal enters the demodulator for demodulation processing.