Temperature monitoring system

Abstract

The invention relates to the technical field of temperature detection, in particular to a temperature monitoring system which comprises a wide-spectrum light source generation module, an optical fiber coupling module, an optical fiber coupling module and a control module. The optical fiber coupling module transmits the data to the temperature sensing module; the temperature sensing module receives the spectrum signal and generates a reflection spectrum signal, and the optical signal demodulation module receives the reflection spectrum signal and demodulates the reflection spectrum signal to obtain temperature information. According to the invention, the reflection spectrum signal of the optical fiber unit is demodulated to obtain rough temperature positioning, the problems of possible overlapping and difficult distinguishing of the interference spectrum in wide temperature section measurement are solved, the interference spectrum of the direct band gap semiconductor unit is demodulated, the temperature measurement result of the optical fiber unit is subjected to refined compensation, and the measurement accuracy is improved. And high-resolution and high-precision temperature measurement is realized in a wide temperature measurement range.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature detection, and in particular to a temperature monitoring system. Background Art

[0002] In modern industry, scientific research and daily life, the demand for accurate and real-time temperature monitoring is growing. Although traditional temperature sensors, such as thermocouples and thermal resistors, perform well in many applications, they have limitations in high speed, high precision and remote monitoring. Especially in complex environments or places where direct contact is difficult, the installation, maintenance and accuracy assurance of traditional sensors face challenges.

[0003] As a new type of temperature monitoring method, optical fiber temperature sensor has gradually attracted widespread attention due to its advantages such as anti-electromagnetic interference, corrosion resistance, remote monitoring and easy networking. Among them, the fiber Bragg grating (FBG) sensor can achieve a wide range of temperature measurement due to its unique wavelength reflection characteristics. The working principle of the FBG sensor is based on the relationship between the grating period and the reflection wavelength. When the ambient temperature changes, the period of the FBG will change accordingly, causing the reflection wavelength to shift. The temperature value can be calculated by measuring this shift. However, the accuracy and interchangeability of FBG sensors are not high, and they are easily disturbed by environmental physical quantities. The packaging form is first, and it has great limitations, making it difficult to achieve accurate temperature measurement in complex and changing environments. Summary of the invention

[0004] (I) Purpose of the invention

[0005] The object of the present invention is to provide a temperature monitoring system capable of realizing high-precision temperature measurement within a wide temperature measurement range.

[0006] (II) Technical solution

[0007] In order to solve the above problems, the present invention provides a temperature monitoring system, comprising: a wide-spectrum light source generating module, an optical fiber coupling module, a temperature sensing module and an optical signal demodulation module;

[0008] The broadband light source generating module outputs a spectrum signal and transmits it to the optical fiber coupling module;

[0009] The optical fiber coupling module receives the spectrum signal and transmits it to the temperature sensing module;

[0010] The temperature sensing module receives the spectrum signal and generates a reflection spectrum signal, and transmits the reflection spectrum signal to the optical fiber coupling module, wherein the temperature sensing module includes an optical fiber unit, a direct bandgap semiconductor unit and a reflection unit;

[0011] The optical fiber coupling module receives the reflection spectrum signal and transmits it to the optical signal demodulation module;

[0012] The optical signal demodulation module receives the reflected spectrum signal and performs demodulation to obtain temperature information.

[0013] In another aspect of the present invention, preferably, the optical fiber unit, the direct bandgap semiconductor unit and the reflective unit are connected in sequence, the direct bandgap semiconductor unit forms a Fabry-Perot cavity structure, and a portion of the optical fiber unit close to the direct bandgap semiconductor unit is provided with a fiber Bragg grating structure;

[0014] The Bragg fiber grating structure is used to reflect the optical signal to form a Bragg reflection spectrum;

[0015] The Fabry-Perot cavity structure generates an interference spectrum through the reflection unit.

[0016] In another aspect of the present invention, preferably,

[0017] The incident end of the direct bandgap semiconductor unit is connected to one end of the optical fiber unit, the reflection end of the direct bandgap semiconductor unit is far away from the optical fiber unit, and the reflection end is provided with the reflection unit;

[0018] The incident end and the reflection end are arranged in parallel, and the incident end and the reflection end are parallel mirror surfaces of the Fabry-Perot cavity structure.

[0019] In another aspect of the present invention, preferably,

[0020] The Fabry-Perot cavity structure for generating an interference spectrum comprises:

[0021] After passing through the Bragg fiber grating structure, part of the optical signal in the spectrum signal enters the direct bandgap semiconductor unit, and is continuously reflected and transmitted between the incident end and the reflection end, forming parallel light with decreasing amplitude between the incident end and the reflection end;

[0022] An interference spectrum is generated based on the parallel light.

[0023] In another aspect of the present invention, preferably,

[0024] The optical signal demodulation module includes a division unit, an FBG analysis unit, a direct bandgap semiconductor analysis unit and a fitting unit;

[0025] The division unit divides the reflection spectrum signal according to the wavelength band to obtain the FBG data segment and the direct bandgap semiconductor data segment;

[0026] The FBG analysis unit compares and analyzes the FBG data segment with the FBG segment temperature information-wavelength curve to obtain first temperature information;

[0027] The direct bandgap semiconductor analysis unit compares and analyzes the direct bandgap semiconductor data segment with a direct bandgap semiconductor segment temperature information-wavelength curve to obtain second temperature information;

[0028] The fitting unit fits the first temperature information and the second temperature information to obtain temperature data.

[0029] In another aspect of the present invention, preferably,

[0030] The FBG analysis unit compares and analyzes the FBG data segment with the FBG segment temperature information-wavelength curve to obtain the first temperature information, including:

[0031] Performing peak analysis on the real-time wavelength of the FBG data segment to extract the Bragg wavelength;

[0032] The extracted Bragg wavelength is compared with the FBG segment temperature information-wavelength curve to obtain the first temperature information.

[0033] In another aspect of the present invention, preferably,

[0034] The direct bandgap semiconductor analysis unit compares and analyzes the direct bandgap semiconductor data segment with a direct bandgap semiconductor segment temperature information-wavelength curve to obtain second temperature information, including:

[0035] Performing Gaussian fitting on the direct bandgap semiconductor data segment to extract the peak wavelength of the interference spectrum;

[0036] The extracted peak wavelength is compared with a temperature information-wavelength curve of a direct bandgap semiconductor segment to obtain second temperature information.

[0037] In another aspect of the present invention, preferably,

[0038] The fitting unit fits the first temperature information with the second temperature information to obtain temperature data, including:

[0039] The first temperature information is used to locate a temperature interval, and the second temperature information is used to determine temperature data in the temperature interval.

[0040] In another aspect of the present invention, preferably, it further comprises an extended optical cable, through which the broadband light source generating module, the optical fiber coupling module, the temperature sensing module and the optical signal demodulation module are connected.

[0041] In another aspect of the present invention, preferably,

[0042] The optical fiber coupling module comprises: an input unit, an output unit, a reflection unit and a return unit;

[0043] The input unit is used to receive a spectrum signal from a wide spectrum light source generating module;

[0044] The output unit is used to transmit the spectral signal to the temperature sensing module;

[0045] The reflection unit is used to receive the reflection spectrum signal returned by the temperature sensing module;

[0046] The return unit is used to transmit the reflection spectrum signal to the optical signal demodulation module.

[0047] (III) Beneficial effects

[0048] The above technical solution of the present invention has the following beneficial technical effects:

[0049] The wide-spectrum light source generating module, the optical fiber coupling module, the temperature sensing module and the optical signal demodulation module of the present invention form a complete and highly integrated system. The temperature sensing module includes an FBG-direct bandgap semiconductor dual mode. The two modes are measured in coordination, which can effectively reduce the measurement error. The combination of the optical fiber coupling module and the temperature sensing module ensures the anti-electromagnetic interference and insulation of the system. In a complex electromagnetic environment, such as a transformer substation, a communication base station and other places, the system can work stably without being affected by external electromagnetic interference on the measurement result. The optical signal demodulation module demodulates the reflection spectrum signal generated by the temperature sensing module, and obtains a rough temperature positioning by demodulating the reflection spectrum signal of the optical fiber unit, thereby solving the problems of overlap and difficulty in resolution of the interference spectrum in wide temperature range measurement. At the same time, the interference spectrum of the direct bandgap semiconductor unit is demodulated, and the temperature measurement result of the optical fiber unit is refined and compensated, thereby realizing high-resolution and high-precision temperature measurement in a wide temperature measurement range. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention;

[0051] Figure 2 is a schematic diagram of a temperature sensing module according to an embodiment of the present invention;

[0052] Figure 3 is a schematic diagram of the structure of an optical fiber coupling module according to an embodiment of the present invention;

[0053] Figure 4 is a schematic diagram of the structure of an optical signal demodulation module according to an embodiment of the present invention;

[0054] Figure 5 It is a schematic diagram of the structure of a direct bandgap semiconductor;

[0055] Reference numerals:

[0056] 1: Broad spectrum light source generation module, 2: Fiber coupling module, 3: Temperature sensing module, 4: Optical signal demodulation module,

[0057] 201: input unit, 202: output unit, 203: reflection unit, 204: return unit, 301: optical fiber unit, 302: direct bandgap semiconductor unit, 303: reflection unit, 401: division unit, 402: FBG analysis unit, 403: direct bandgap semiconductor analysis unit, 404: fitting unit. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0059] The accompanying drawings show schematic diagrams of layer structures according to embodiments of the present invention. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clarity. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0060] Obviously, the described embodiments are only some embodiments of the present invention, but not all 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.

[0061] 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.

[0062] The present invention will be described in more detail below with reference to the accompanying drawings. In each of the accompanying drawings, the same elements are represented by similar reference numerals. For the sake of clarity, the various parts in the accompanying drawings are not drawn to scale.

[0063] Embodiment 1

[0064] A temperature monitoring system, Figure 1 FIG. 1 shows a schematic diagram of the overall structure of an embodiment of the present invention. Figure 1 As shown, it includes: a wide spectrum light source generating module 1, an optical fiber coupling module 2, a temperature sensing module 3 and an optical signal demodulating module 4;

[0065] The broadband light source generating module 1 outputs a spectrum signal and transmits it to the optical fiber coupling module 2; the broadband light source generating module generates a spectrum signal within a certain wavelength range, and the generated spectrum signal has a wide coverage range and can cover the working wavelength of FBG (fiber Bragg grating) and direct bandgap semiconductor.

[0066] The optical fiber coupling module 2 receives the spectral signal and transmits it to the temperature sensing module 3; the optical fiber coupling module 2 serves as a transmission channel for the spectral signal, and is responsible for efficiently transmitting the spectral signal generated by the wide-spectrum light source to the temperature sensing module, and receiving the reflected spectral signal returned by the temperature sensing module.

[0067] The temperature sensing module 3 receives the spectrum signal and generates a reflection spectrum signal, and transmits the reflection spectrum signal to the optical fiber coupling module 2. Figure 2 FIG. 1 shows a schematic diagram of a temperature sensing module according to an embodiment of the present invention. Figure 2 As shown, in this embodiment, the temperature sensing module 3 includes an optical fiber unit 301, a direct bandgap semiconductor unit 302 and a reflection unit 303; the optical fiber unit 301, the direct bandgap semiconductor unit 302 and the reflection unit 303 are connected in sequence, the direct bandgap semiconductor unit 302 forms a Fabry-Perot cavity structure, and the portion of the optical fiber unit 301 close to the direct bandgap semiconductor unit 302 is provided with a fiber Bragg grating structure; the Bragg fiber grating structure is used to reflect the light signal to form a Bragg reflection spectrum; the Bragg fiber grating structure has a specific periodic refractive index change, when the spectrum signal passes through, only the specific wavelength light that meets the Bragg condition will be reflected back to form a Bragg reflection spectrum. The Fabry-Perot cavity structure generates an interference spectrum through the reflection unit 303. Furthermore, the incident end of the direct bandgap semiconductor unit 302 is connected to one end of the optical fiber unit 301, the reflection end of the direct bandgap semiconductor unit 302 is far away from the optical fiber unit 301, and the reflection end is provided with the reflection unit 303; the incident end and the reflection end are arranged in parallel, and the incident end and the reflection end are parallel mirrors of the Fabry-Perot cavity structure. The Fabry-Perot cavity structure is used to generate an interference spectrum, including: after a part of the optical signal in the spectrum signal passes through the Bragg fiber grating structure, it enters the direct bandgap semiconductor unit 302, and is continuously reflected and transmitted between the incident end and the reflection end through the reflection unit 303, so as to form parallel light with decreasing amplitude between the incident end and the reflection end; and an interference spectrum is generated according to the parallel light. When the temperature changes, the thermal expansion effect of the direct bandgap semiconductor unit 302 will change the optical path difference of the Fabry-Perot cavity, thereby causing the interference spectrum to shift. By detecting the change in the interference spectrum, high-precision measurement of temperature can be achieved. Among them, Figure 5 shows a schematic diagram of the structure of a direct bandgap semiconductor, such as Figure 5As shown, in the structure of a direct bandgap semiconductor, the top of the valence band and the bottom of the conduction band are in the same position in momentum space, and the energy gap between the conduction band and the valence band, i.e., the bandgap, allows electrons to absorb photons (light of a specific wavelength) and directly transition from the top of the valence band (the position with the highest energy in the valence band) to the bottom of the conduction band (the position with the lowest energy in the conduction band), and the photon energy is equal to or greater than its bandgap width. This transition process does not involve the participation of other intermediate energy levels or states, so it is called a "direct" transition. Semiconductors with this energy band structure are called direct bandgap semiconductors. In this embodiment, the material of the direct bandgap semiconductor crystal 2 can be: gallium arsenide (GaAs), gallium nitride (GaN), indium phosphide (InP), etc.;

[0068] The optical fiber coupling module 2 receives the reflected spectrum signal and transmits it to the optical signal demodulation module 4; the optical fiber coupling module 2 receives the reflected spectrum signal and transmits it to the optical signal demodulation module 4; Figure 3 FIG. 4 shows a schematic diagram of the structure of an optical fiber coupling module according to an embodiment of the present invention. Figure 3 As shown, in this embodiment, the optical fiber coupling module 2 includes: an input unit 201, an output unit 202, a reflection unit 203 and a return unit 204;

[0069] The input unit 201 is used to receive the spectrum signal from the wide-spectrum light source generating module 1; the input unit 201 is the entrance of the optical fiber coupling module 2, and is used to receive the spectrum signal from the wide-spectrum light source generating module 1. This spectrum signal is generated by the wide-spectrum light source and covers the working wavelength range of the temperature sensing module 3. The input unit 201 needs to ensure the efficient reception of the spectrum signal and stably transmit it to the output unit 202.

[0070] The output unit 202 is used to transmit the spectral signal to the temperature sensing module 3; the output unit 202 is responsible for transmitting the spectral signal from the optical fiber coupling module 2 to the temperature sensing module 3. The output unit 202 needs to ensure the integrity and accuracy of the spectral signal so that the temperature sensing module 3 can correctly receive and process these signals. The design of the output unit 202 takes into account factors such as the loss of the optical fiber, the coupling efficiency, and the integrity of the signal to ensure the stability and accuracy of the spectral signal during the transmission process.

[0071] The reflection unit 203 is used to receive the reflection spectrum signal returned by the temperature sensing module 3; the reflection unit 203 is an important part of the optical fiber coupling module 2, and receives the reflection spectrum signal returned by the temperature sensing module 3. The reflection spectrum signal contains temperature information and is the key data that the system needs to demodulate. The reflection unit 203 ensures the efficient reception of the reflection spectrum signal and stably transmits it to the return unit 204 for transmission.

[0072] The optical signal demodulation module 4 receives the reflected spectrum signal and performs demodulation to obtain temperature information. The demodulation process includes converting the reflected spectrum signal into an electrical signal and extracting the temperature information through a signal processing algorithm. Figure 4 FIG. 4 shows a schematic diagram of the structure of an optical signal demodulation module according to an embodiment of the present invention. Figure 4 As shown, the optical signal demodulation module 4 includes a dividing unit 401, a FBG analysis unit 402, a direct bandgap semiconductor analysis unit 403 and a fitting unit 404;

[0073] The dividing unit 401 divides the reflected spectrum signal according to the bands to obtain the FBG data segment and the direct bandgap semiconductor data segment; the dividing unit 401 is the preprocessing part of the optical signal demodulation module 4, and the dividing unit 401 divides the received reflected spectrum signal according to the bands to distinguish the FBG data segment and the direct bandgap semiconductor data segment. The dividing standard is to set the corresponding band data of the FBG data segment and the direct bandgap semiconductor data segment, and divide the reflected spectrum signal according to the set band data.

[0074] The FBG analysis unit 402 compares and analyzes the FBG data segment with the FBG segment temperature information-wavelength curve to obtain the first temperature information; the FBG analysis unit 402 receives the FBG data segment output by the division unit 401, and compares and analyzes it with the known FBG segment temperature information-wavelength curve, which can be obtained through experiments. In this embodiment, the FBG analysis unit 402 compares and analyzes the FBG data segment with the FBG segment temperature information-wavelength curve to obtain the first temperature information, including:

[0075] Perform peak-finding analysis on the real-time wavelength of the FBG data segment to extract the Bragg wavelength; use a peak detection algorithm to find the peak position in the FBG data segment, where the peak position corresponds to the position of the Bragg wavelength;

[0076] The extracted Bragg wavelength is compared with the FBG segment temperature information-wavelength curve to obtain the first temperature information. The extracted Bragg wavelength is matched with the known FBG segment temperature information-wavelength curve. According to the matching result, the temperature value corresponding to the extracted Bragg wavelength is searched from the FBG segment temperature information-wavelength curve.

[0077] The direct bandgap semiconductor analysis unit 403 compares and analyzes the direct bandgap semiconductor data segment with the direct bandgap semiconductor segment temperature information-wavelength curve to obtain the second temperature information; the direct bandgap semiconductor analysis unit 403 receives the direct bandgap semiconductor data segment output by the division unit 401, and compares and analyzes it with the known direct bandgap semiconductor segment temperature information-wavelength curve, including: performing Gaussian fitting on the direct bandgap semiconductor data segment to extract the interference spectrum peak wavelength; comparing the extracted peak wavelength with the direct bandgap semiconductor segment temperature information-wavelength curve to obtain the second temperature information. The direct bandgap semiconductor segment temperature information-wavelength curve can be obtained through experiments.

[0078] The fitting unit 404 fits the first temperature information with the second temperature information to obtain temperature data, including: the first temperature information is used to locate the temperature interval, and the second temperature information is used to determine the temperature data in the temperature interval. The temperature detected according to the FBG data segment is a wider temperature range, and an approximate temperature range is obtained. Then, the second temperature information obtained according to the direct bandgap semiconductor data segment is refined and compensated within the approximate temperature range to obtain more accurate temperature data. In this embodiment, within the temperature measurement range of -20 to 150°C, a temperature sensitivity of 0.12nm / °C, a wavelength demodulation resolution of 0.1pm, and a temperature demodulation error of ±0.41°C are achieved.

[0079] Furthermore, in this embodiment, an extended optical cable is also included, and the broadband light source generating module, the optical fiber coupling module, the temperature sensing module and the optical signal demodulation module are connected by the extended optical cable. The use of the extended optical cable makes the connection between the broadband light source generating module, the optical fiber coupling module, the temperature sensing module and the optical signal demodulation module no longer limited to a short distance or a fixed position. By extending the optical cable, these modules can be flexibly arranged according to actual needs, which greatly improves the convenience and adaptability of system installation.

[0080] The wide-spectrum light source generating module, the optical fiber coupling module, the temperature sensing module and the optical signal demodulation module of the present invention form a complete and highly integrated system. The temperature sensing module includes an FBG-direct bandgap semiconductor dual mode. The two modes are measured in coordination, which can effectively reduce the measurement error. The combination of the optical fiber coupling module and the temperature sensing module ensures the anti-electromagnetic interference and insulation of the system. In a complex electromagnetic environment, such as a transformer substation, a communication base station and other places, the system can work stably without being affected by external electromagnetic interference on the measurement result. The optical signal demodulation module demodulates the reflection spectrum signal generated by the temperature sensing module, and obtains a rough temperature positioning by demodulating the reflection spectrum signal of the optical fiber unit, thereby solving the problems of overlap and difficulty in resolution of the interference spectrum in wide temperature range measurement. At the same time, the interference spectrum of the direct bandgap semiconductor unit is demodulated, and the temperature measurement result of the optical fiber unit is refined and compensated, thereby realizing high-resolution and high-precision temperature measurement in a wide temperature measurement range.

[0081] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

[0082] In the above description, the technical details of patterning and etching of each layer are not described in detail. However, those skilled in the art should understand that various means in the prior art can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above.

[0083] The present invention has been described above with reference to the embodiments of the present invention. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims and their equivalents. Without departing from the scope of the present invention, a person skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

[0084] Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.

[0085] 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 temperature monitoring system, characterized in that: include: A wide-spectrum light source generating module (1), an optical fiber coupling module (2), a temperature sensing module (3) and an optical signal demodulating module (4); The wide spectrum light source generating module (1) outputs a spectrum signal and transmits it to the optical fiber coupling module (2); The optical fiber coupling module (2) receives the spectrum signal and transmits it to the temperature sensing module (3); The temperature sensing module (3) receives the spectrum signal and generates a reflection spectrum signal, and transmits the reflection spectrum signal to the optical fiber coupling module (2), wherein the temperature sensing module (3) comprises an optical fiber unit (301), a direct bandgap semiconductor unit (302) and a reflection unit (303); The optical fiber coupling module (2) receives the reflection spectrum signal and transmits it to the optical signal demodulation module (4); The optical signal demodulation module (4) receives the reflected spectrum signal and performs demodulation to obtain temperature information.

2. The temperature monitoring system according to claim 1, characterized in that: The optical fiber unit (301), the direct bandgap semiconductor unit (302) and the reflection unit (303) are connected in sequence, the direct bandgap semiconductor unit (302) forms a Fabry-Perot cavity structure, and a portion of the optical fiber unit (301) close to the direct bandgap semiconductor unit (302) is provided with a fiber Bragg grating structure; The Bragg fiber grating structure is used to reflect the optical signal to form a Bragg reflection spectrum; The Fabry-Perot cavity structure generates an interference spectrum through the reflection unit (303).

3. The temperature monitoring system according to claim 1, characterized in that: The incident end of the direct bandgap semiconductor unit (302) is connected to one end of the optical fiber unit (301), the reflection end of the direct bandgap semiconductor unit (302) is away from the optical fiber unit (301), and the reflection end is provided with the reflection unit (303); The incident end and the reflection end are arranged in parallel, and the incident end and the reflection end are parallel mirror surfaces of the Fabry-Perot cavity structure.

4. The temperature monitoring system according to claim 3, characterized in that: The Fabry-Perot cavity structure for generating an interference spectrum comprises: After passing through the Bragg fiber grating structure, part of the optical signal in the spectrum signal enters the direct bandgap semiconductor unit (302), and is continuously reflected and transmitted between the incident end and the reflection end, thereby forming parallel light with decreasing amplitude between the incident end and the reflection end; An interference spectrum is generated based on the parallel light.

5. The temperature monitoring system according to claim 1, characterized in that: The optical signal demodulation module (4) comprises a dividing unit (401), an FBG analysis unit (402), a direct bandgap semiconductor analysis unit (403) and a fitting unit (404); The division unit (401) divides the reflection spectrum signal according to the wavelength band to obtain the FBG data segment and the direct bandgap semiconductor data segment; The FBG analysis unit (402) compares and analyzes the FBG data segment with the FBG segment temperature information-wavelength curve to obtain first temperature information; The direct bandgap semiconductor analysis unit (403) compares and analyzes the direct bandgap semiconductor data segment with a direct bandgap semiconductor segment temperature information-wavelength curve to obtain second temperature information; The fitting unit (404) fits the first temperature information and the second temperature information to obtain temperature data.

6. The temperature monitoring system according to claim 5, characterized in that: The FBG analysis unit (402) compares and analyzes the FBG data segment with the FBG segment temperature information-wavelength curve to obtain the first temperature information, including: Performing peak analysis on the real-time wavelength of the FBG data segment to extract the Bragg wavelength; The extracted Bragg wavelength is compared with the FBG segment temperature information-wavelength curve to obtain the first temperature information.

7. The temperature monitoring system according to claim 5, characterized in that: The direct bandgap semiconductor analysis unit (403) compares and analyzes the direct bandgap semiconductor data segment with a direct bandgap semiconductor segment temperature information-wavelength curve to obtain second temperature information, including: Performing Gaussian fitting on the direct bandgap semiconductor data segment to extract the peak wavelength of the interference spectrum; The extracted peak wavelength is compared with a temperature information-wavelength curve of a direct bandgap semiconductor segment to obtain second temperature information.

8. The temperature monitoring system according to claim 5, characterized in that: The fitting unit (404) fits the first temperature information and the second temperature information to obtain temperature data, including: The first temperature information is used to locate a temperature interval, and the second temperature information is used to determine temperature data in the temperature interval.

9. The temperature monitoring system according to claim 1, characterized in that: It also includes an extended optical cable, through which the wide-spectrum light source generating module, the optical fiber coupling module, the temperature sensing module and the optical signal demodulation module are connected.

10. The temperature monitoring system according to claim 1, characterized in that: The optical fiber coupling module (2) comprises: an input unit (201), an output unit (202), a reflection unit (203) and a return unit (204); The input unit (201) is used to receive a spectrum signal from a wide-spectrum light source generating module (1); The output unit (202) is used to transmit the spectral signal to the temperature sensing module (3); The reflection unit (203) is used to receive the reflection spectrum signal returned by the temperature sensing module (3); The return unit (204) is used to transmit the reflection spectrum signal to the optical signal demodulation module (4).

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