CN102928001A - Forest fire monitoring wireless sensing system based on fiber bragg grating sensing technology - Google Patents

Abstract

The invention relates to the fields of optical fiber grating sensing technology and forest fire prevention technology. The invention discloses a wireless sensing system for forest fire monitoring based on fiber grating sensing technology. Adjustment device, data processing module, wireless communication module. Its characteristics are: the solar power supply system is used to supply power to the light source, the light source is connected to the fiber grating, the fiber grating is connected to the photoelectric detection device with a single-mode optical fiber, the output end of the photoelectric detection device is connected to the demodulation device, and the output of the demodulation device The terminal is connected with the data processing and wireless communication module. The beneficial effects of the present invention are: applying the fiber grating sensing technology to the field of forest fire monitoring, opening up a new field for the application of fiber grating sensors, and providing a new method for safety and health monitoring in complex and harsh environments in forests and means.

Description

Wireless Sensing System for Forest Fire Monitoring Based on Fiber Bragg Grating Sensing Technology

technical field

The invention relates to the field of optical fiber grating sensing technology and forest fire prevention technology, in particular to a wireless sensing system for forest fire monitoring based on optical fiber grating sensing technology.

Background technique

Forest fire has the characteristics of wide occurrence, great destructiveness, and extremely difficult rescue. It ranks first among the three natural disasters (fire, disease, and insect damage) that destroy forests. At present, the forest fire monitoring methods commonly used in the world mainly include: manual patrol, video surveillance, forest ranger aircraft and infrared remote sensing fire early warning aircraft patrol, satellite patrol monitoring system, and forest fire automatic early warning system based on various sensor networks. Judging from the current use situation, manual patrols consume too much manpower and are likely to cause missed reports; the use of forest ranger aircraft consumes too much financial resources and is not a long-term solution; satellite images or images obtained through remote video mainly reflect fire , smog, etc., it is difficult to reflect the dynamic changes of direct environmental and meteorological factors such as temperature, humidity, and atmospheric pressure; at the same time, because the observation effect is limited by the terrain, the coverage is small, and there are dead spots and gaps. Establishing an automatic early warning system for forest fire monitoring to realize all-round three-dimensional monitoring of forest fires in the air and on the ground is the development direction of forest fire prevention, and finally realize the intelligence and informationization of forest fire prevention. The wireless sensor network is the core and key of this automatic early warning system.

At present, there have been many reports on the research of wireless sensor network applied in forest fire monitoring system at home and abroad. Most of the sensors that make up the wireless sensor network are electrical sensors. Electrical sensors are low in price and mature in technology, but they cannot be used under harsh conditions such as high temperature, high pressure, strong electromagnetic interference, and chemical corrosion. The sensory network will be destroyed. Optical fiber sensors have been widely used in many fields such as military, civil engineering, electric power, petrochemical, biomedicine, and environmental monitoring due to their unique advantages such as light weight, easy reuse, anti-electromagnetic interference, and anti-chemical corrosion. The wireless sensing system for forest fire monitoring based on fiber grating sensing technology has not been reported yet.

At present, there is no wireless sensing system for forest fire monitoring based on fiber grating sensing technology.

Contents of the invention

The purpose of the present invention is to use the fiber grating sensor as the sensing element to measure the physical quantities of the forest such as temperature, humidity, wind speed and direction, and smog concentration, and analyze and process the measured signal, and transmit the data to the forest through the wireless transmission module. The remote control center constitutes a wireless sensing system for forest fire monitoring based on fiber grating sensing technology.

The invention is a wireless sensing system for forest fire monitoring based on fiber grating sensing technology, which uses a fiber grating sensor as a sensing probe and transmits data signals in a wireless manner. The retrieval results show that there is no patent report on the wireless sensor system for forest fire monitoring that is consistent with it at present.

The invention discloses a wireless sensing system for forest fire monitoring based on fiber grating sensing technology, and its technical scheme is as follows:

This wireless sensor system for forest fire monitoring based on fiber grating sensing technology includes power supply system, light source, single-mode fiber, fiber grating, photoelectric detection device, demodulation device, data processing module, and wireless communication module.

The wireless sensor system for forest fire monitoring based on fiber Bragg grating sensing technology is characterized by: using a solar power supply system to power the light source, using a single-mode fiber to connect the light source to the fiber grating, and the fiber grating to the photoelectric detection device, and the photoelectric detection device The output end of the demodulation device is connected with the demodulation device, and the output end of the demodulation device is connected with the data processing and wireless communication module.

The power supply system is powered by solar energy, and supplies power to the sensor system without erecting an antenna, and takes power locally.

The light source is a tunable light source or a broadband light source, and its wave band should be able to cover the wave band of the fiber grating.

The fiber Bragg grating is an optical device that can change the spectrum or light intensity due to physical parameters such as temperature, strain, humidity, and smoke concentration, that is, a fiber Bragg grating, a long-period fiber grating, or a tilted fiber grating.

The fiber grating can be packaged correspondingly according to different measurement requirements to form a sensing probe for measuring various physical quantities. It is also possible to form a fiber grating array in a system in a series, parallel or series-parallel connection.

The wireless communication module can also form a sensor network with other sensors through a wireless network to complete information exchange, cooperate with each other, and complete functions such as data extraction, analysis, and decision-making.

The demodulation device can be a demodulation device of wavelength or beat frequency or light intensity signal, and different demodulation means can be adopted according to different sensing signals.

The wireless sensing system for forest fire monitoring based on fiber grating sensing technology of the present invention applies fiber grating sensing technology to the field of forest fire monitoring, while maintaining the characteristics of high sensitivity and anti-interference of fiber grating sensors, combined with wireless communication Technology, can produce a modular, low-cost fiber grating wireless sensing system. It opens up a new field for the application of the fiber grating sensor, so that it can form a large-scale sensor network system more flexibly and conveniently on the basis of maintaining the original excellent characteristics. Provide new methods and means for safety and health monitoring in complex and harsh environments in forests.

Description of drawings

Fig. 1 is a structural diagram of a wireless sensing system for forest fire monitoring based on fiber grating sensing technology of the present invention.

Detailed ways

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

This wireless sensor system for forest fire monitoring based on fiber grating sensing technology includes: power supply system, light source, fiber grating, photoelectric detection device, demodulation device, data processing module, wireless communication module, and single-mode fiber for connection. It is characterized in that the light source is connected with the optical fiber grating, and the optical fiber grating and the photoelectric detection device are respectively connected by a single-mode optical fiber. The output end of the photoelectric detection device is connected with the demodulation device, and the output end of the demodulation device is connected with the data processing and wireless communication module.

The power supply system can adopt solar power supply system.

The light source can be a broadband light source or a narrowband tunable light source.

Fiber Bragg gratings can be optical devices such as Bragg fiber gratings, long-period fiber gratings, or tilted fiber gratings, which can cause changes in spectrum or light intensity due to physical parameters such as temperature, strain, humidity, and smoke concentration.

Fiber Bragg gratings can be packaged according to different measurement requirements to form sensing probes for measuring various physical quantities. It is also possible to form a fiber grating array in a system in a series, parallel or series-parallel connection.

The photoelectric detection device adopts PIN photodiode of InGaAs material.

The demodulation device can be a demodulation device of wavelength or beat frequency or light intensity signal, and different demodulation means can be adopted according to different sensing signals of the fiber grating. Send the data to the data processing and wireless communication module.

The wireless communication module can adopt 3G communication mode, and can also form a sensor network with other sensors through a wireless network to complete information exchange, cooperate with each other, and complete functions such as data extraction, analysis, and decision-making.

Example :

The power supply system uses solar cells to supply power to the light source. The working band of the light source is 1525-1575nm. The fiber grating adopts long-period fiber grating, the central wavelength is 1530nm, the bandwidth is 5nm, and the reflectivity at the central wavelength is 95%. The photoelectric detection device adopts a PIN photodiode made of InGaAs material, its response center wavelength is 1300nm, and its response bandwidth is 600nm. The demodulation device adopts a tunable fiber filter or a linear demodulator based on light intensity, which can detect the wavelength of the fiber grating. The single-mode optical fiber adopts the single-mode optical fiber in the 1550nm band. The wireless communication module uses a 3G wireless signal transmitter to transmit the data information to the remote monitoring center through the 3G network.

In practical application, a single-mode optical fiber is used to connect the light source with the fiber grating, the fiber grating and the photoelectric detection device correspondingly.

Claims (9)

1. wireless sensing system based on the forest fire monitoring of fiber grating sensing technology, it comprises: electric power system, light source, fiber grating, photoelectric detection system, demodulating equipment, data processing module, wireless communication module connects and uses single-mode fiber, it is characterized in that: respectively light source is linked to each other with photoelectric detection system with fiber grating, fiber grating with single-mode fiber; The output terminal of photoelectric detection system is connected with demodulating equipment, and the output terminal of demodulating equipment processes with data and wireless communication module is connected.

2. the wireless sensing system of the forest fire monitoring based on fiber grating sensing technology according to claim 1, it is characterized in that: electric power system is solar powered.

3. the wireless sensing system of the forest fire monitoring based on fiber grating sensing technology according to claim 1, it is characterized in that: light source is wideband light source or tunable optical source, and its wave band can cover the wave band of fiber grating.

4. the wireless sensing system of the forest fire monitoring based on fiber grating sensing technology according to claim 1, it is characterized in that: sensor is the fiber grating of bragg grating, long period fiber grating or other type.

5. the wireless sensing system of the forest fire monitoring based on fiber grating sensing technology according to claim 1, it is characterized in that: fiber grating can require to encapsulate according to different measurements, measure the various physical quantitys in the forest fire monitoring, such as temperature, humidity, smokescope etc.

6. the wireless sensing system of the forest fire monitoring based on fiber grating sensing technology according to claim 1, it is characterized in that: fiber grating can take the connected mode of a plurality of serial or parallel connections or series-parallel connection to consist of optical fibre optical grating sensing array.

7. the wireless sensing system of the forest fire monitoring based on fiber grating sensing technology according to claim 1, it is characterized in that: photoelectric detection system adopts the PIN photodiode of InGaAs material.

8. the wireless sensing system of the forest fire monitoring based on fiber grating sensing technology according to claim 1, it is characterized in that: demodulating equipment is the demodulating equipment of wavelength or beat frequency or light intensity signal, can take different demodulation means according to the different transducing signal of fiber grating.

9. the wireless sensing system of the forest fire monitoring based on fiber grating sensing technology according to claim 1, it is characterized in that: wireless communication module adopts the 3G communication modes, can also consist of sensing network by wireless network and other sensors, finish and exchange information, cooperate with each other, finish the functions such as data extraction, analysis, decision-making.

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