Fiber bragg grating temperature demodulator parameter calibration method

Abstract

The invention relates to a fiber bragg grating temperature demodulator parameter calibration method, in particular to a fiber bragg grating temperature demodulator adopting a tunable laser to tune wavelength. Parameters of the fiber bragg grating temperature demodulator comprise a parameter table of multiple groups of parameters, and each group of parameters is composed of three digital quantities. The three digital quantities are converted into current signals of a driving light source through a D / A conversion circuit of the optical fiber grating temperature demodulator light source driving circuit, a left grating area, a right grating area and a phase area of the tunable laser are driven respectively, different digital quantity combinations are sent to the demodulator in a circulating mode during working, optical signals with different wavelengths are output, and the optical signals with different wavelengths are output. Tuning control on the output light wavelength of the light source is realized.

Description

Technical Field

[0001] The invention relates to a parameter calibration method for a fiber Bragg grating temperature demodulator, in particular to a fiber Bragg grating temperature demodulator using a tunable laser to tune the wavelength, and belongs to the technical field of optical fiber sensing. Background Art

[0002] With the continuous development of aerospace technology, the requirements for the weight, reliability and service life of spacecraft are getting higher and higher. As a new generation of temperature measurement products, fiber Bragg grating temperature interrogator has the characteristics of light weight, flexible deployment, strong adaptability to space environment, etc. It is very suitable for large-scale multi-point temperature measurement of large-scale precision structures of spacecraft. In order to realize multi-point temperature measurement of satellites, fiber Bragg grating temperature sensor networks can be laid in the satellite cabin and fuel tanks to monitor the temperature changes of various satellite components.

[0003] The fiber Bragg grating temperature measurement demodulator is the core equipment of the grating temperature measurement system. Its performance directly affects the temperature measurement accuracy of the system. The left grating area (I LR )、Right grating area (I RR ) and phase region (I PH ), can output a fixed sequence of wavelengths, but in actual use, the output wavelength has deviations or the relative error of the output wavelength in high and low temperature environments is too large, resulting in a decrease in demodulation accuracy; light of the same wavelength can be generated by tuning different current sequences. Therefore, in order to improve the temperature measurement accuracy of the demodulator, the parameters of the fiber Bragg grating temperature demodulator are calibrated, and parameters with more stable output are selected to improve the demodulation accuracy of the demodulator in normal temperature and full temperature environments. Summary of the invention

[0004] The technical problem solved by the invention is to overcome the deficiencies of the prior art, provide a parameter calibration method for a fiber grating temperature demodulator, and improve the temperature measurement accuracy of the demodulator.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The invention discloses a parameter calibration method for a fiber grating temperature demodulator, comprising:

[0007] Build a test system;

[0008] Setting includes a combination of initial parameters and corresponding wavelengths;

[0009] According to the combination of digital quantities, the parameters of the fiber Bragg grating temperature demodulator are calibrated in a normal temperature environment using a test system to obtain the wavelength measurement value in the normal temperature environment;

[0010] Calculate the absolute error between the measured wavelength and the set wavelength at room temperature;

[0011] According to the absolute error, obtain the parameters that meet the error requirements under normal temperature environment;

[0012] According to the parameters that meet the error requirements under normal temperature environment, the test system is used to calibrate the parameters of the fiber Bragg grating temperature demodulator in high and low temperature environments to obtain the wavelength measurement values ​​under high and low temperature environments;

[0013] Calculate the extreme value error of wavelength measurement values ​​at different temperature points under high and low temperature environments;

[0014] According to the extreme value error, the corresponding parameters that meet the error requirements are selected to form a parameter table of the fiber Bragg grating temperature demodulator.

[0015] Furthermore, in the above method, the test system comprises: a host computer, an optical wavelength meter, an optical connector and a temperature demodulator; wherein,

[0016] The fiber Bragg grating temperature demodulator and the optical wavelength meter are connected via an optical connector; the temperature demodulator and the optical wavelength meter are connected to a host computer respectively;

[0017] The host computer is used to send a digital quantity combination to the temperature demodulator; receive the wavelength measurement value of the wavelength meter, and store it in one-to-one correspondence with the digital quantity combination;

[0018] A temperature demodulator is used to emit an optical signal of a corresponding wavelength according to a combination of digital quantities;

[0019] The optical wavelength meter is used to receive the optical signal sent by the temperature demodulator, analyze the corresponding wavelength measurement value, and send it to the host computer.

[0020] Furthermore, in the above method, the parameters of the fiber Bragg grating temperature demodulator are calibrated in a normal temperature environment to obtain the wavelength measurement value in the normal temperature environment, specifically:

[0021] S1, placing the demodulator in a room temperature environment, connecting the fiber Bragg grating temperature demodulator and the optical wavelength meter through an optical connector, and connecting the temperature demodulator and the optical wavelength meter to a host computer respectively;

[0022] S2, the host computer sends a digital quantity combination to the temperature demodulator; the temperature demodulator sends out an optical signal of the corresponding wavelength according to the digital quantity combination;

[0023] S3, the optical wavelength meter receives the optical signal sent by the temperature demodulator and parses the corresponding wavelength measurement value;

[0024] S4, the host computer software receives the wavelength measurement value of the wavelength meter and saves it in one-to-one correspondence with the digital quantity combination in step S2;

[0025] S5, repeating steps S2 to S4 to complete the wavelength information collection of all digital quantity combinations, and obtaining the wavelength measurement values ​​of all digital quantity combinations under normal temperature environments.

[0026] Furthermore, in the above method, the parameters of the fiber Bragg grating temperature demodulator are calibrated in a high and low temperature environment to obtain the wavelength measurement value in the high and low temperature environment, specifically:

[0027] S31, placing the fiber Bragg grating temperature demodulator into a temperature box, connecting the fiber Bragg grating temperature demodulator and the optical wavelength meter through an optical connector, and connecting the temperature demodulator and the optical wavelength meter to a host computer respectively;

[0028] S32, setting the temperature of the incubator according to the use environment requirements, and setting the insulation time corresponding to each incubator temperature;

[0029] S33, the host computer cyclically sends the corresponding digital quantity combination to the temperature demodulator; the temperature demodulator sends out an optical signal of the corresponding wavelength according to the digital quantity combination;

[0030] S34, the optical wavelength meter receives the optical signal sent by the temperature demodulator and parses the corresponding wavelength measurement value;

[0031] S35, the host computer receives the wavelength measurement value and stores it in one-to-one correspondence with the digital quantity combination in S33;

[0032] S36, repeating steps S33 to S35, completing the wavelength information collection of all digital quantity combinations, and obtaining wavelength measurement values ​​under high and low temperature environments.

[0033] Furthermore, in the above method, the parameters that meet the error requirements under normal temperature environment are obtained based on the absolute error, specifically: judging whether the absolute error is greater than the normal temperature error threshold, if so, eliminating a set of parameters corresponding to the absolute error; if not, determining that a set of parameters corresponding to the absolute error are parameters that meet the error requirements under normal temperature environment.

[0034] Furthermore, in the above method, the calculation of the extreme value error of the wavelength measurement value at different temperature points under high and low temperature environments is specifically as follows:

[0035] From the wavelength measurement values ​​under high and low temperature environments, select the maximum and minimum values ​​of the same set of parameters at different temperatures;

[0036] The difference between the maximum and minimum values ​​is calculated as the extreme value error.

[0037] Furthermore, in the above method, the corresponding parameters that meet the error requirements are selected according to the extreme value error to form a fiber Bragg grating temperature demodulator parameter table, which is specifically:

[0038] Determine whether the extreme value error is less than the high and low temperature thresholds; if so, determine that a set of parameters corresponding to the extreme value error is the corresponding parameter when the error requirement is met; if not, eliminate the set of parameters corresponding to the extreme value error.

[0039] Furthermore, in the above method, the setting includes a digital combination of initial parameters and corresponding wavelengths, specifically:

[0040] Generate a wavelength list based on the wavelength step;

[0041] According to the wavelength list, generate the parameters corresponding to each wavelength;

[0042] Each group of parameters consists of multiple digital quantities to form a digital quantity combination.

[0043] Furthermore, in the above method, the normal temperature error threshold is ±1.5 pm.

[0044] Furthermore, in the above method, the high and low temperature thresholds are 5 to 10 pm.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] (1) The present invention adopts the technical solution of normal temperature calibration of fiber Bragg grating demodulator parameters to achieve the purpose of normal temperature screening and calibration of lasers and circuits in the demodulator, and solves the problem of stability of the demodulator output optical signal in the full wavelength range at normal temperature;

[0047] (2) The present invention adopts the technical solution of full-temperature calibration of fiber Bragg grating demodulator parameters to realize calibration of the demodulator over the full temperature range, solves the problem of stability of the demodulator output optical signal over the full temperature range, and improves the temperature adaptability of the demodulator and the measurement accuracy over the full temperature range;

[0048] (3) The present invention adopts the parameter calibration technology of the fiber Bragg grating demodulator to achieve an absolute temperature measurement accuracy of better than ±0.5°C over the entire temperature range of the fiber Bragg grating temperature demodulator, thereby ensuring the temperature measurement accuracy of the fiber Bragg grating;

[0049] (4) The fiber Bragg grating interrogator parameter calibration method adopted by the present invention can make the tunable laser in the fiber Bragg grating temperature interrogator output stable and appropriate wavelength light without tuning the optical power of the laser, thereby ensuring the accuracy of the interrogator.

[0050] (5) The present invention calibrates the parameters of the demodulator under normal temperature and high and low temperature environments, and completes the fiber Bragg grating temperature demodulator parameter table by selecting parameters whose absolute error under normal temperature and relative error under high and low temperature environments meet the requirements, thereby improving the temperature measurement accuracy of the demodulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1This is a diagram of the calibration equipment and connection relationship of the present invention;

[0052] Figure 2 This is a schematic diagram of driving a tunable laser according to the present invention. DETAILED DESCRIPTION

[0053] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0054] The invention discloses a parameter calibration method for a fiber grating temperature demodulator, comprising:

[0055] Build a test system;

[0056] Setting includes a combination of initial parameters and corresponding wavelengths;

[0057] According to the combination of digital quantities, the parameters of the fiber Bragg grating temperature demodulator are calibrated in a normal temperature environment using a test system to obtain the wavelength measurement value in the normal temperature environment;

[0058] Calculate the absolute error between the measured wavelength and the set wavelength at room temperature;

[0059] According to the absolute error, obtain the parameters that meet the error requirements under normal temperature environment;

[0060] According to the parameters that meet the error requirements under normal temperature environment, the test system is used to calibrate the parameters of the fiber Bragg grating temperature demodulator in high and low temperature environments to obtain the wavelength measurement values ​​under high and low temperature environments;

[0061] Calculate the extreme value error of wavelength measurement values ​​at different temperature points under high and low temperature environments;

[0062] According to the extreme value error, the corresponding parameters that meet the error requirements are selected to form a parameter table of the fiber Bragg grating temperature demodulator.

[0063] Preferably, if Figure 1 As shown, the test system includes: a host computer, an optical wavelength meter, an optical connector and a temperature demodulator; wherein,

[0064] The fiber Bragg grating temperature demodulator and the optical wavelength meter are connected via an optical connector; the temperature demodulator and the optical wavelength meter are connected to a host computer respectively;

[0065] The host computer is used to send a digital quantity combination to the temperature demodulator; receive the wavelength measurement value of the wavelength meter, and store it in one-to-one correspondence with the digital quantity combination;

[0066] A temperature demodulator is used to emit an optical signal of a corresponding wavelength according to a combination of digital quantities;

[0067] The optical wavelength meter is used to receive the optical signal sent by the temperature demodulator, analyze the corresponding wavelength measurement value, and send it to the host computer.

[0068] Preferably, the parameters of the fiber Bragg grating temperature demodulator are calibrated in a normal temperature environment to obtain the wavelength measurement value in the normal temperature environment, specifically:

[0069] S1, placing the demodulator in a room temperature environment, connecting the fiber Bragg grating temperature demodulator and the optical wavelength meter through an optical connector, and connecting the temperature demodulator and the optical wavelength meter to a host computer respectively;

[0070] S2, the host computer sends a digital quantity combination to the temperature demodulator; the temperature demodulator sends out an optical signal of the corresponding wavelength according to the digital quantity combination;

[0071] S3, the optical wavelength meter receives the optical signal sent by the temperature demodulator and parses the corresponding wavelength measurement value;

[0072] S4, the host computer software receives the wavelength measurement value of the wavelength meter and saves it in one-to-one correspondence with the digital quantity combination in step S2;

[0073] S5, repeating steps S2 to S4 to complete the wavelength information collection of all digital quantity combinations, and obtaining the wavelength measurement values ​​of all digital quantity combinations under normal temperature environments.

[0074] Preferably, in a high and low temperature environment, the parameters of the fiber Bragg grating temperature demodulator are calibrated to obtain the wavelength measurement value in the high and low temperature environment, specifically:

[0075] S31, placing the fiber Bragg grating temperature demodulator into a temperature box, connecting the fiber Bragg grating temperature demodulator and the optical wavelength meter through an optical connector, and connecting the temperature demodulator and the optical wavelength meter to a host computer respectively;

[0076] S32, setting the temperature of the incubator according to the use environment requirements, and setting the insulation time corresponding to each incubator temperature;

[0077] S33, the host computer cyclically sends the corresponding digital quantity combination to the temperature demodulator; the temperature demodulator sends out an optical signal of the corresponding wavelength according to the digital quantity combination;

[0078] S34, the optical wavelength meter receives the optical signal sent by the temperature demodulator and parses the corresponding wavelength measurement value;

[0079] S35, the host computer receives the wavelength measurement value and stores it in one-to-one correspondence with the digital quantity combination in S33;

[0080] S36, repeating steps S33 to S35, completing the wavelength information collection of all digital quantity combinations, and obtaining wavelength measurement values ​​under high and low temperature environments.

[0081] Preferably, based on the absolute error, parameters that meet the error requirements under normal temperature environment are obtained, specifically: determine whether the absolute error is greater than the normal temperature error threshold, if so, eliminate a group of parameters corresponding to the absolute error; if not, determine that a group of parameters corresponding to the absolute error are parameters that meet the error requirements under normal temperature environment.

[0082] Preferably, the extreme value error of the wavelength measurement value at different temperature points under high and low temperature environments is calculated as follows:

[0083] From the wavelength measurement values ​​under high and low temperature environments, select the maximum and minimum values ​​of the same set of parameters at different temperatures;

[0084] The difference between the maximum and minimum values ​​is calculated as the extreme value error.

[0085] Preferably, according to the extreme value error, corresponding parameters that meet the error requirements are selected to form a fiber Bragg grating temperature demodulator parameter table, specifically:

[0086] Determine whether the extreme value error is less than the high and low temperature thresholds; if so, determine that a set of parameters corresponding to the extreme value error is the corresponding parameter when the error requirement is met; if not, eliminate the set of parameters corresponding to the extreme value error.

[0087] Preferably, the setting includes a digital combination of initial parameters and corresponding wavelengths, specifically:

[0088] Generate a wavelength list based on the wavelength step;

[0089] According to the wavelength list, generate the parameters corresponding to each wavelength;

[0090] Each group of parameters consists of multiple digital quantities to form a digital quantity combination.

[0091] Preferably, the normal temperature error threshold is ±1.5 pm.

[0092] Preferably, the high and low temperature thresholds are 5-10 pm.

[0093] Example

[0094] The present embodiment provides a parameter calibration method for a fiber Bragg grating temperature demodulator, including parameter calibration under normal temperature and high and low temperature environments, firstly performing normal temperature calibration, and then performing high and low temperature fixed temperature point calibration.

[0095] The fiber grating temperature demodulator involved in the present invention is required to have a temperature measurement accuracy of ±0.5°C in a full temperature environment, and the use environment of the demodulator is 0-50°C.

[0096] The specific steps of the calibration method under normal temperature environment are as follows:

[0097] 1. Place the demodulator in a room temperature environment with good heat dissipation, connect the fiber Bragg grating temperature demodulator and the optical wavelength meter through an optical connector, and connect the temperature demodulator and the optical wavelength meter to the host computer respectively, such as Figure 1 ;

[0098] 2. Send the parameter table containing parameter 1, parameter 2, parameter 3 and SETλ to the fiber Bragg grating temperature demodulator through the host computer, and convert it into a current sequence by the D / A conversion circuit of the light source driving circuit in the demodulator, so as to drive the tunable laser to emit a light signal of a specific wavelength, such as Figure 2 ;

[0099] 3. The optical wavelength meter receives the optical signal sent by the fiber Bragg grating temperature demodulator, analyzes the corresponding wavelength and sends it to the host computer. The host computer stores TESTλ and the parameters in a one-to-one correspondence, as shown in Table 1;

[0100] Table 1

[0101] Parameter 1 (LSB) Parameter 2 (LSB) Parameter 3 (LSB) SETλ(nm) TESTλ(nm) <![CDATA[I LR 1]]> <![CDATA[I RR 1]]> <![CDATA[I PH 1]]> 1528.6 <![CDATA[λ1]]> <![CDATA[I LR 2]]> <![CDATA[I RR 2]]> <![CDATA[I PH 2]]> 1528.62 <![CDATA[λ2]]> <![CDATA[I LR 3]]> <![CDATA[I RR 3]]> <![CDATA[I PH 3]]> 1528.64 <![CDATA[λ3]]> …… …… …… …… …… <![CDATA[I LR n-1]]> <![CDATA[I RR n-1]]> <![CDATA[I PH n-1]]> 1554.38 <![CDATA[λ n-1 ]]> <![CDATA[I LR n]]> <![CDATA[I RR n]]> <![CDATA[I PH n]]> 1554.4 <![CDATA[λ n ]]>

[0102] 4. Calculate the difference between TESTλ and SETλ in each row of parameters and replace the parameters with a difference > 1.5pm.

[0103] The specific steps of the calibration method under high and low temperature environments are as follows:

[0104] 1. Place the fiber Bragg grating temperature demodulator in the incubator, connect the fiber Bragg grating temperature demodulator and the optical wavelength meter through the optical connector, and connect the temperature demodulator and the optical wavelength meter to the host computer respectively, such as Figure 1 ;

[0105] 2. Set the temperature of the incubator to 0℃, 10℃, 20℃, 30℃, 40℃, and 50℃, and keep warm for 4 hours at each temperature point;

[0106] 3. The parameter table containing parameter 1, parameter 2, parameter 3 and SETλ is sent to the fiber Bragg grating temperature demodulator through the host computer loop, and converted into a current sequence by the D / A conversion circuit of the light source driving circuit in the demodulator, thereby driving the tunable laser to emit a light signal of a specific wavelength, such as Figure 2 ;

[0107] 4. The optical wavelength meter receives the optical signal sent by the fiber Bragg grating temperature demodulator, analyzes the corresponding wavelength and sends it to the host computer. The host computer stores TESTλ and the parameters in a one-to-one correspondence, as shown in Table 1;

[0108] 5. Calculate the relative difference of TESTλ at different temperatures for points with the same parameters 1, 2 and 3, and replace the parameters with a difference > 5 pm.

[0109] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

[0110] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A method for calibrating parameters of a fiber Bragg grating temperature demodulator, characterized in that: include: Build a test system; Setting includes a combination of initial parameters and corresponding wavelengths; According to the combination of digital quantities, the parameters of the fiber Bragg grating temperature demodulator are calibrated in a normal temperature environment using a test system to obtain the wavelength measurement value in the normal temperature environment; Calculate the absolute error between the measured wavelength and the set wavelength at room temperature; According to the absolute error, obtain the parameters that meet the error requirements under normal temperature environment; According to the parameters that meet the error requirements under normal temperature environment, the test system is used to calibrate the parameters of the fiber Bragg grating temperature demodulator in high and low temperature environments to obtain the wavelength measurement values ​​under high and low temperature environments; Calculate the extreme value error of wavelength measurement values ​​at different temperature points under high and low temperature environments; According to the extreme value error, the corresponding parameters that meet the error requirements are selected to form a parameter table of the fiber Bragg grating temperature demodulator.

2. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 1, characterized in that: The test system comprises: a host computer, an optical wavelength meter, an optical connector and a temperature demodulator; wherein, The fiber Bragg grating temperature demodulator and the optical wavelength meter are connected via an optical connector; the temperature demodulator and the optical wavelength meter are connected to a host computer respectively; The host computer is used to send a digital quantity combination to the temperature demodulator; receive the wavelength measurement value of the wavelength meter, and store it in one-to-one correspondence with the digital quantity combination; A temperature demodulator is used to emit an optical signal of a corresponding wavelength according to a combination of digital quantities; The optical wavelength meter is used to receive the optical signal sent by the temperature demodulator, analyze the corresponding wavelength measurement value, and send it to the host computer.

3. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 1, characterized in that: In a normal temperature environment, the parameters of the fiber Bragg grating temperature demodulator are calibrated to obtain the wavelength measurement value in the normal temperature environment, specifically: S1, placing the demodulator in a room temperature environment, connecting the fiber Bragg grating temperature demodulator and the optical wavelength meter through an optical connector, and connecting the temperature demodulator and the optical wavelength meter to a host computer respectively; S2, the host computer sends a digital quantity combination to the temperature demodulator; the temperature demodulator sends out an optical signal of the corresponding wavelength according to the digital quantity combination; S3, the optical wavelength meter receives the optical signal sent by the temperature demodulator and parses the corresponding wavelength measurement value; S4, the host computer software receives the wavelength measurement value of the wavelength meter and saves it in one-to-one correspondence with the digital quantity combination in step S2; S5, repeating steps S2 to S4 to complete the wavelength information collection of all digital quantity combinations, and obtaining the wavelength measurement values ​​of all digital quantity combinations under normal temperature environments.

4. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 1, characterized in that: In high and low temperature environments, the parameters of the fiber Bragg grating temperature demodulator are calibrated to obtain the wavelength measurement values ​​in high and low temperature environments, specifically: S31, placing the fiber Bragg grating temperature demodulator into a temperature box, connecting the fiber Bragg grating temperature demodulator and the optical wavelength meter through an optical connector, and connecting the temperature demodulator and the optical wavelength meter to a host computer respectively; S32, setting the temperature of the incubator according to the use environment requirements, and setting the insulation time corresponding to each incubator temperature; S33, the host computer cyclically sends the corresponding digital quantity combination to the temperature demodulator; the temperature demodulator sends out an optical signal of the corresponding wavelength according to the digital quantity combination; S34, the optical wavelength meter receives the optical signal sent by the temperature demodulator and parses the corresponding wavelength measurement value; S35, the host computer receives the wavelength measurement value and stores it in one-to-one correspondence with the digital quantity combination in S33; S36, repeating steps S33 to S35, completing the wavelength information collection of all digital quantity combinations, and obtaining wavelength measurement values ​​under high and low temperature environments.

5. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 1, characterized in that: The method of obtaining parameters that meet the error requirements under normal temperature environment based on the absolute error is specifically as follows: determining whether the absolute error is greater than the normal temperature error threshold, and if so, eliminating a group of parameters corresponding to the absolute error; if not, determining that a group of parameters corresponding to the absolute error are parameters that meet the error requirements under normal temperature environment.

6. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 1, characterized in that: The calculation of the extreme value error of the wavelength measurement value at different temperature points under high and low temperature environments is specifically: From the wavelength measurement values ​​under high and low temperature environments, select the maximum and minimum values ​​of the same set of parameters at different temperatures; The difference between the maximum and minimum values ​​is calculated as the extreme value error.

7. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 1, characterized in that: According to the extreme value error, the corresponding parameters that meet the error requirements are selected to form a fiber Bragg grating temperature demodulator parameter table, which is specifically: Determine whether the extreme value error is less than the high and low temperature thresholds; if so, determine that a set of parameters corresponding to the extreme value error is the corresponding parameter when the error requirement is met; if not, eliminate the set of parameters corresponding to the extreme value error.

8. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 1, characterized in that: The settings include initial parameters and several digital quantity combinations of corresponding wavelengths, specifically: Generate a wavelength list based on the wavelength step; According to the wavelength list, generate the parameters corresponding to each wavelength; Each group of parameters consists of multiple digital quantities to form a digital quantity combination.

9. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 5, characterized in that: The normal temperature error threshold is ±1.5 pm.

10. A method for calibrating parameters of a fiber Bragg grating temperature demodulator according to claim 7, characterized in that: The high and low temperature thresholds are 5 to 10 pm.

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