CN113810106B - Safety monitoring method and device of optical fiber energy information common transmission system - Google Patents

Abstract

The invention discloses a safety monitoring method and device for an optical fiber energy information co-transmission system. On the one hand, the invention monitors the optical fiber link by monitoring the reflected optical power generated by Rayleigh scattering at the central station; on the other hand, using high power The nonlinear effect of energy light in the fiber, by monitoring the Brillouin scattered light power and Raman backscattered light power generated by the nonlinear effect at the central station, and then monitoring the optical power of the incoming fiber in real time to avoid excessive optical power. Damage from fiber bursts. The invention uses simple devices to monitor the reflected power at the transmitting end, and provides a protection scheme of real-time monitoring and low-delay control for the information-energy co-transmission system.

Description

Safety monitoring method and device for optical fiber energy information co-transmission system

technical field

The invention relates to the technical field of optoelectronics and optical fiber communication, in particular to a safety monitoring method and device for an optical fiber energy information co-transmission system.

Background technique

In the new generation of wireless communication systems, in order to solve the contradiction between the shortage of existing wireless communication spectrum resources and the explosive growth of data traffic services, the working frequency band of wireless communication is expanding towards the millimeter wave and even the terahertz frequency band. With the improvement of the working frequency band of the radio frequency signal, the transmission loss of the signal in the air is greatly increased, and the diffraction ability is weakened, which leads to the reduction of the coverage of a single base station. In order to ensure the coverage area, the number of required base stations increases sharply, and operators will face a sharp rise in total power consumption and hardware costs, as well as difficulties in supplying power to a large number of base stations. In addition, in the rapid connection of communication systems after natural disasters, and when base stations are erected in remote areas, it is difficult to obtain local power for communication equipment. The optical fiber-based energy information co-transmission technology can solve the above problems. The optical energy and optical information are transmitted to the base station together through an optical fiber, which not only realizes the remote autonomous power supply of the base station, but also realizes the communication function between the central station and the base station.

Due to the high optical power of the energy transmitted by the optical fiber energy information co-transmission system, once the laser leaks, it will cause serious damage to people's eyes and skin, especially in indoor micro base station application scenarios, which have potential safety hazards. Moreover, the real-time monitoring and evaluation of the working status of the system link facilitates the warning and response of faults. Therefore, the present invention proposes a safety monitoring method and device for an optical fiber energy information co-transmission system, which uses a simple device at the transmitting end to monitor the reflected power, and provides a protection scheme of real-time monitoring and low-latency control for the information-energy co-transmission system.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies of the prior art, and to provide a safety monitoring method and device for an optical fiber energy information co-transmission system.

The purpose of the present invention is to be achieved through the following technical solutions: a safety monitoring method for an optical fiber energy information co-transmission system, comprising the following steps:

S1: Obtain the Rayleigh scattered light, Brillouin scattered light and Raman backscattered light generated in the optical fiber by the energy light;

S2: The Rayleigh scattered light, Brillouin scattered light and Raman backscattered light pass through the optical coupler to the second port of the optical circulator, and are output from the third port of the optical circulator to the second optical wavelength division multiplexing The device is divided into three channels by the second optical wavelength division multiplexer and then enters the power supply laser control system respectively and obtains the Rayleigh scattered light power P _E1 , the Brillouin scattered light power P _E2 , and the Raman backscattered light power P _E3 ;

S3: The energy-supplying laser control system measures the Rayleigh threshold P R , the Brillouin threshold P SBS and the Raman threshold P SRS of the Rayleigh scattered light, Brillouin scattered light and Raman backscattered light respectively, and calculates the Rayleigh threshold P _R , the Brillouin threshold P _SBS and the Raman threshold P _SRS . The scattered light measurement threshold P _{E1-R =} γ ₁ *PR , the Brillouin scattered light measurement threshold P _E2-SBS =γ ₂ *P _SBS , the Raman backscattered light measurement threshold P _E3-SRS =γ ₃ * P _SRS , the 0.1<γ ₁ <0.5, 0.1<γ ₂ <0.5, 0.1<γ ₃ <0.5;

S4: The Rayleigh scattered light power P _E1 , the Brillouin scattered light power P _E2 , and the Raman backscattered light power P _E3 are smaller than the Rayleigh scattered light measurement threshold P _E1-R and the Brillouin scattered light measurement threshold P When _E2-SBS and Raman backscattered light measurement threshold P _E3-SRS , the energy-supplying laser works normally.

The central wavelengths of the Rayleigh scattered light, Brillouin scattered light, and Raman backscattered light are λ ₂ , λ ₂ +Δλ ₁ , λ ₂ +Δλ ₂ respectively and enter the Rayleigh control system of the power supply laser control system respectively. The Δλ ₁ is the wavelength difference corresponding to the stimulated Brillouin frequency shift, and the Δλ ₂ is the Raman back scattered light. corresponding wavelength difference.

The step S4 also includes the following situations:

①: When the optical fiber is worn or broken, the energy light undergoes Fresnel reflection in the optical fiber, the Rayleigh scattered light power increases sharply, and the Rayleigh scattered light power P _E1 received by the Rayleigh scattered light port of the power supply laser control system is higher than that of Rayleigh scattered light. Using the scattered light measurement threshold P _E1-R , the energized laser control system issues a Type 1 alarm and turns off the energized laser;

②: When the energy supply laser uses a high-power energy supply laser with a narrow linewidth, and the energy light power P _E2 exceeds the Brillouin threshold P _SBS , the energy light will produce a wavelength offset of △λ ₁ during the fiber transmission process. At this time, the Brillouin scattering light power P _E2 received by the Brillouin scattering light port of the energy-supplying laser control system is higher than the Brillouin scattering light measurement threshold P _E2-SBS , and the energy-supplying laser controls The system issues a Type 2 alarm and shuts down the powered laser.

③: When the energy-supplying laser uses a high-power energy-supplying laser with a wide linewidth, and the energy light power P _HPLD exceeds the Raman threshold P _SRS , the energy light produces a stimulated pull with a wavelength offset of Δλ ₂ during the fiber transmission process. Raman backscattered light, at this time, the Raman backscattered light power _PE3 received by the Raman backscattered light port of the energy-supplying laser control system is higher than the Raman backscattered light measurement threshold _PE3-SRS , and the energy supply The laser control system issues a Type 3 alarm and shuts down the powered laser.

A safety monitoring device for an optical fiber energy information co-transmission system, comprising a second optical wavelength division multiplexer, a power supply laser, and a power supply laser control system for analyzing power, the second optical wavelength division multiplexer and the power supply laser The control system is connected, and the energy-supplying laser control system is connected with the energy-supplying laser.

Further, the power supply laser control system includes a Rayleigh scattered light port, a Brillouin scattered light port, and a Raman backscattered light port, and the second optical wavelength division multiplexer is respectively connected with the Rayleigh scattered light port, the Brillouin scattered light port, and the Raman backscattered light port. The Brillouin scattered light port and the Raman backscattered light port are connected, the Rayleigh scattered light port is used to measure the power of Rayleigh scattered light and compare it with the measurement threshold of Rayleigh scattered light, the Brillouin scattered light The port is used to measure the power of the Brillouin scattered light and compare it with the Brillouin scattered light measurement threshold, and the Raman backscattered light port is used to measure the power of the Raman backscattered light and compare it with the Raman backscattered light. Compare to scattered light measurement thresholds.

The transmission optical fibers can be single-mode optical fibers, multi-mode optical fibers, multi-core optical fibers, and double-clad optical fibers.

In the central station, the first port of the optical circulator receives the energy light output by the energizing laser, and the energy light is output to the optical coupler through the second port of the optical circulator, and then transmitted to the base station through the optical fiber through the optical coupler. The energy light will generate Rayleigh scattered light, Brillouin scattered light and Raman backscattered light in the fiber. The three kinds of reflected light pass through the optical coupler to the second port of the optical circulator and from the third port of the optical circulator. The output is sent to the second optical wavelength division multiplexer, divided into three channels by the second optical wavelength division multiplexer, and then respectively enters the power supply laser control system and obtains Rayleigh scattered light power P _E1 , Brillouin scattered light power P _E2 , Raman light power Backscattered light power P _E3 . Once the monitoring power exceeds the Rayleigh scattered light measurement threshold, the Brillouin scattered light measurement threshold, and the Raman backscattered light measurement threshold range, the energy-supplying laser control system will issue an alarm and turn off the energy-supplying laser, and subsequent staff will conduct troubleshooting. The energy light is branched by the first wavelength division multiplexer in the base station, and the energy light is converted into electric energy by the photovoltaic converter to supply power to the first photodetector and the electric amplifier in the base station. The laser is used to provide an optical carrier, and an electro-optical modulator is used to load the data signal on the optical carrier. The optical carrier is coupled with the energy light through an optical coupler after passing through the optical isolator, and then transmitted to the remote base station through an optical fiber. In the base station, the first wavelength division multiplexer is used for branching, and after photoelectric conversion is performed by the first photodetector, it is amplified by an electric amplifier and finally transmitted through an antenna.

The beneficial effects of the present invention are:

1. In the present invention, the power of the reflected light is analyzed by the power supply laser control system, so as to control the opening and closing of the power supply laser.

2. The present invention converts the energy light into electrical energy through the photovoltaic converter to supply power for the first photodetector and the electric amplifier.

Description of drawings

Fig. 1 is the schematic diagram of the present invention;

In the figure: 1-laser, 2-electro-optical modulation, 3-optical isolator, 4-optical coupler, 5-optical fiber, 6-first optical wavelength division multiplexer, 7-first photodetector, 8-electrical amplifier , 9-antenna, 10-powered laser, 11-optical circulator, 12-photovoltaic converter, 13-second optical wavelength division multiplexer, 14-powered laser control system.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations. Thus, the following detailed description of the embodiments of the invention provided in the accompanying drawings are not intended to limit the scope of the invention as claimed, but are merely representative of selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

The dotted line with arrows in Figure 1 is the circuit, and the solid line is the optical path.

As shown in FIG. 1 , a method and device for safety monitoring of an optical fiber energy information co-transmission system, the energy supply laser 10 generates high-power energy light with a center wavelength of λ ₂ and a power of P _HPLD , and the first port of the optical circulator 11 The high-power energy light is received, and the high-power energy light is output to the optical coupler 4 through the second port of the optical circulator 11 , and is coupled into a multimode fiber 5 through the optical coupler 4 . The high-power energy light generates Rayleigh scattered light, Brillouin scattered light and Raman backscattered light in the multimode fiber 5, and the three kinds of reflected light pass through the optical coupler 4 to the second port of the optical circulator 11 and from the optical ring. The third port of the device 11 is output to the second optical wavelength division multiplexer 13, and is divided into three channels by the second optical wavelength division multiplexer 13. The center wavelengths are λ ₂ , λ ₂ +Δλ ₁ , λ ₂ +Δλ ₂ respectively The optical signal enters the Rayleigh scattered light port, the Brillouin scattered light port, and the Raman backscattered light port of the high-power laser control system 14. The scattered light power P _E1 , the Brillouin scattered light power P _E2 , and the Raman backscattered light power P _E3 are analyzed, where Δλ ₁ is the wavelength difference corresponding to the stimulated Brillouin frequency shift, and Δλ ₂ is the Raman The wavelength difference corresponding to the backscattered light. The high-power laser control system 14 measures the Rayleigh threshold P _R , the Brillouin threshold P _SBS and the Raman threshold P _SRS of the Rayleigh scattered light, the Brillouin scattered light and the Raman backscattered light respectively, and calculates the Rayleigh scattered light measurement threshold P _{E1-R =} γ ₁ *PR , Brillouin scattered light measurement threshold P _E2-SBS =γ ₂ *P _SBS , Raman backscattered light measurement threshold P _E3-SRS =γ ₃ *P _SRS , said 0.1<γ ₁ <0.5, 0.1<γ ₂ <0.5, 0.1<γ ₃ <0.5;

When the high-power energy optical power P _HPLD output by the high-power energy-supplying laser 10 is lower than the Brillouin threshold P _SBS and the Raman threshold P _SRS and the optical fiber is in good condition, the three ports of the high-power energy-supplying laser control system 14 measure the The optical powers _PE1 , _PE2 and _PE3 are respectively smaller than the Rayleigh scattered light measurement threshold _PE1-R , the Brillouin scattered light measurement threshold _PE2-SBS , the Raman backscattered light measurement threshold _PE3-SRS , and the signal energy The co-transmission system works normally. When the optical fiber transmission system is worn or broken, the high-power energy light undergoes Fresnel reflection in the multimode fiber 5, and the power of the Rayleigh scattered light increases sharply. When the Rayleigh scattered light power _PE1 is higher than the Rayleigh scattered light measurement threshold _PE1-R , the high-power powered laser control system 14 issues a Type 1 alarm and automatically turns off the high-power powered laser 10 . When the high-power energy-supplying laser 10 uses a high-power energy-supplying laser 10 with a narrow linewidth, and the energy light power P _HPLD exceeds the Brillouin threshold P _SBS , the energy light will generate a wavelength shift of Δ during the transmission process of the optical fiber 5 . The stimulated Brillouin scattering light of λ ₁ , at this time, the Brillouin scattering light power P _E2 received by the Brillouin scattering light port of the high-power laser control system 14 is higher than the Brillouin scattering light measurement threshold P _{E2 -SBS} , the high power powered laser control system 14 issues a Type 2 alarm and shuts down the high power powered laser 10. When the high-power energy-supplying laser 10 uses the high-power energy-supplying laser 10 with a wide linewidth, and the energy light power P _HPLD exceeds the Raman threshold P _SRS , the energy light produces a wavelength offset of Δλ ₂ during the transmission process of the optical fiber 5 . Stimulated Raman backscattered light, at this time, the Raman backscattered light power P _E3 received by the Raman backscattered light port of the high-power laser control system 14 is higher than the Raman backscattered light measurement threshold P _E3-SRS , the high-power laser control system 14 issues a type 3 alarm and turns off the high-power laser 10, and then the staff will carry out system troubleshooting.

Laser 1 is a distributed feedback laser (DFB-LD) 1 with a narrow linewidth with a central wavelength of λ _2. The optical carrier generated by laser 1 passes through a Mach-Zehnder electro-optic modulator 2 working in a push-pull mode. The electro-optic modulator 2 loads a radio frequency signal with a frequency of f _RF onto the optical carrier to obtain modulated signal light, and the modulated signal light passes through the optical isolator 3 to isolate the energy reflected light, so as to prevent the reflected light from affecting the laser 1 and the Mach-Zehnder electro-optic modulator. 2. Damage is caused, and the modulated signal and the high-power energy light are coupled into the same multimode fiber 5 through the optical coupler 4. After the coupled light is transmitted to the remote base station, the first wavelength division multiplexer 6 is used to separate the modulated signal light from the high-power energy light. The high-power energy light is converted into electrical energy with a success rate of αP _HPLD through a high-power photovoltaic converter 12 with a matching wavelength of λ ₂ , where α is the conversion efficiency of the energy of the entire system, and the electrical energy is supplied to the highly saturated first photodetector 7 in the base station. And the electric amplifier 8 provides the driving voltage. The modulated signal light undergoes photoelectric conversion through the first photodetector 7 and is amplified by the electric amplifier 8, and finally emitted from the antenna 9 to realize the communication function between the central station and the base station.

The above are only preferred embodiments of the present invention, and it should be understood that the present invention is not limited to the form disclosed herein, should not be construed as an exclusion of other embodiments, but may be used in various other combinations, modifications and environments, and Modifications can be made within the scope of the concepts described herein, from the above teachings or from skill or knowledge in the relevant field. However, modifications and changes made by those skilled in the art do not depart from the spirit and scope of the present invention, and should all fall within the protection scope of the appended claims of the present invention.

Claims (5)

1. a safety monitoring method of an optical fiber energy information transmission system, is characterized in that, comprises the following steps: S1: Obtain the Rayleigh scattered light, Brillouin scattered light and Raman backscattered light generated in the optical fiber (5) by the energy light; S2: The Rayleigh scattered light, Brillouin scattered light and Raman backscattered light pass through the optical coupler (4) to the input end of the optical circulator (11) and output from the output end of the optical circulator (11) to the second optical wavelength division multiplexer (13), divided into three channels by the second optical wavelength division multiplexer (13), and then respectively entered into the power supply laser control system (14) and obtained the Rayleigh scattered light power

, Brillouin scattered light power

, Raman backscattered light power

; S3: The energy-supplying laser control system (14) measures the Rayleigh thresholds of the Rayleigh scattered light, the Brillouin scattered light and the Raman backscattered light respectively

, Brillouin threshold

and Raman threshold

And calculate the Rayleigh scattered light measurement threshold

, Brillouin scattering light measurement threshold

, Raman backscattered light measurement threshold

, where 0.1<γ ₁ <0.5, 0.1<γ ₂ <0.5, 0.1<γ ₃ <0.5; S4: the Rayleigh scattered light power

, Brillouin scattered light power

, Raman backscattered light power

less than the Rayleigh scattered light measurement threshold, respectively

, Brillouin scattering light measurement threshold

, Raman backscattered light measurement threshold

When the power supply laser (10) works normally. 2 . The safety monitoring method of a fiber optic energy information co-transmission system according to claim 1 , wherein the central wavelengths of the Rayleigh scattered light, the Brillouin scattered light and the Raman backscattered light are respectively 2 .

,

,

and respectively enter the Rayleigh scattered light port, the Brillouin scattered light port, and the Raman backscattered light port of the energy-supplying laser control system (14).

is the wavelength difference corresponding to the stimulated Brillouin shift, the

is the wavelength difference corresponding to the Raman backscattered light. 3. The method for safety monitoring of an optical fiber energy information co-transmission system according to claim 2, wherein the step S4 also includes the following conditions:

: When the optical fiber (5) is worn or broken, the energy light undergoes Fresnel reflection in the optical fiber (5), the Rayleigh scattered light power increases sharply, and the Rayleigh scattered light port received by the Rayleigh scattered light port of the power supply laser control system (14) Scattered light power

Above the Rayleigh Scattered Light Measurement Threshold

, the power supply laser control system (14) issues a type 1 alarm and turns off the power supply laser (10);

: When the energy supply laser (10) uses a narrow linewidth high power energy supply laser (10), and the energy optical power

exceeds the Brillouin threshold

, the wavelength shift of the energy light during the transmission of the optical fiber (5) is

The stimulated Brillouin scattering light, at this time, the Brillouin scattering light power received by the Brillouin scattering light port of the power supply laser control system (14)

Above the Brillouin scattering light measurement threshold

, the energizing laser control system (14) issues a type 2 alarm and turns off the energizing laser (10);

: When the energy supply laser (10) uses a high-power energy supply laser (10) with a wide linewidth, and the energy optical power

exceeds the Raman threshold

, the wavelength shift of the energy light during the transmission of the fiber (5) is

The stimulated Raman backscattered light, at this time, the power of the Raman backscattered light received by the Raman backscattered light port of the energy-supplying laser control system (14)

Above the Raman Backscattered Light Measurement Threshold

, the energized laser control system (14) issues a Type 3 alarm and turns off the energized laser (10). 4. A safety monitoring device of an optical fiber energy information co-transmission system, the safety monitoring device comprising the safety monitoring method of a fiber optic energy information co-transmission system according to any one of claims 1 to 3, characterized in that : comprising a second optical wavelength division multiplexer (13), a power supply laser (10) and a power supply laser control system (14) for analyzing power, the second optical wavelength division multiplexer (13) and the power supply laser A control system (14) is connected, and the powered laser control system (14) is connected with the powered laser (10). 5 . The safety monitoring device of a fiber optic energy information co-transmission system according to claim 4 , wherein the power supply laser control system ( 14 ) comprises a Rayleigh scattering light port, a Brillouin scattering light port and a Raman backscattered light port, the second optical wavelength division multiplexer (13) is respectively connected to the Rayleigh scattered light port, the Brillouin scattered light port, and the Raman backscattered light port, the Rayleigh scattered light port The port is used to measure the power of Rayleigh scattered light and measure the threshold with Rayleigh scattered light

For comparison, the Brillouin scattered light port is used to measure the power of the Brillouin scattered light and measure the threshold with the Brillouin scattered light

For comparison, the Raman backscattered light port is used to measure the power of the Raman backscattered light and is compared with the Raman backscattered light measurement threshold

Compare.

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