RU2698097C1 - Security system of a fiber-optic communication line and method of providing security of a fiber-optic communication line - Google Patents

Abstract

FIELD: fiber-optic communication lines.

SUBSTANCE: invention relates to fiber-optic communication lines and is intended for transmission of information streams over a long distance and protection of communication lines from extraneous interference. Method employs a security system for a fiber-optic communication line of a fiber-optic communication line, which is extended in a hard-to-reach area with n wells, connected to sewers, comprising sections of safety control sectors, a security control centre, retransmitters, safety sensors and video cameras with batteries, wherein each well has: a controller, a limit switch and an internal video camera, electrically connected to the battery, in first well of optical section of hard-to-reach area for transfer of energy to intermediate and last n-th well splitter is installed, to which laser optical module is connected, and in the intermediate and last n-th well through the splitter to the optical fiber a photoelectric voltage converter connected by electric wires to the battery is connected.

EFFECT: provision of safety systems with energy and its transfer to remote areas of the country and minimization of energy consumption.

10 cl, 16 dwg

Description

The group of inventions relates to fiber-optic communication lines and is intended to transmit information flows over long distances and protect communication lines from outside interference.

Known fiber optic communication line according to the patent of the Russian Federation for the invention No. 2504015 IPC G08B 25/08, publ. 01/10/2014

This system consists of a central control panel, a group of security sensors and a group of geographically remote video monitoring points having a first radio channel for communication with security sensors and a second radio channel for communication with a central control panel. The system is powered by battery or battery packs using inactive standby modes and active video monitoring to save power.

The disadvantages of this system: the complexity and significant difficulties in changing power supplies in remote and hard-to-reach regions of the country.

A known fiber-optic communication line and a method for ensuring its safety according to the patent of the Russian Federation for invention No. 2591205, IPC Н04 В10 / 25, publ. 07/10/2016, prototype.

This security system of a fiber-optic communication line contains two additional single-mode fibers for separate transmission of signals of the outgoing and incoming directions of the communication subsystem.

A method for ensuring the safety of a fiber-optic communication line involves breaking down the protected area of a large economic facility with both an extended and a local configuration into a large number of connected perimeter sections with a perimeter length of each section no more than 10-15 km, which can significantly expand the service area; -optical security system for interconnected subsystems of protection of the ring topology, which implements at each site the function of sensing the perimeter with the help of erentnoy reflectometry, and communication subsystem dual bus topology that implements the function of pre-processing and serial communication between areas of protection subsystem sensing results into a single control center using the temporal and spectral separation of channels and signal regeneration at each site. Two add-on single-mode fibers are introduced into the sensor fiber-optic cable for separate transmission of signals of the outgoing and incoming directions of the communication subsystem, which eliminates the mutual influence of both subsystems of the fiber-optic security system while maintaining high sensitivity to acoustic effects.

The disadvantages of this system: the inability to ensure the energy consumption of means of ensuring the safety of the fiber optic communication line in remote and inaccessible areas of the country.

Objectives of the invention: providing energy security systems and its transfer to hard-to-reach areas of the country and minimizing energy consumption.

Technical result achieved: reduction of energy consumption and its transfer to hard-to-reach areas.

The solution of these problems was achieved in the security system of a fiber-optic communication line, made in a difficult-to-reach area extended with n wells connected by a cable sewer channel, which includes security control sectors, a security control center, repeaters, security sensors and video cameras with batteries, the fact that the control center for security on the radio channel is connected to the repeaters, and security sensors and video cameras on the optical cable for the security system are connected to the ret with an insulator, the cable duct, in which the optical cables are laid, is made under the surface of the soil, while the optical cables are selected for information transfer, for energy and safety systems, in each well there are: a controller, limit switch and an internal video camera connected by electrical connections to a battery, in the first well of the optical fiber section of a hard-to-reach area for transferring energy to the intermediate and the last n-th well, a splitter is installed, to which is connected The black optical module, and in intermediate and final n-th pit through the splitter to the optical fiber connected to the photoelectric voltage converter connected by electrical wires to the battery.

The Y-shaped splitter with two inputs and one output can be used for the first well, and the Y-shaped splitter with one input and two outputs for intermediate and n-th wells.

Outside the part of the intermediate wells, in the presence of natural supports, external video cameras are installed, connected by communication lines to the controller in the nearest well. Wells can be completed in 0.1-1.2 km.

Along the FOCL section in a difficult-to-reach area, repeaters can be installed every 70-80 km to transmit information about the state of the security system via radio channel to the security control center.

Near each well or part thereof, a well perimeter security system may be implemented.

A well perimeter security system may include: a sensor optical fiber laid underground under the well, a signal transmitter, a signal receiver, a converter, an amplifier, a processor, and a memory unit, while the signal transmitter is connected to the input to the sensor optical fiber, and the signal receiver to the output , the output from the signal receiver is connected to the input to the converter, the output of which is connected to the input to the amplifier, and the output from the amplifier is connected to the input to the processor, the output from the processor is connected to the input to the controller, to the second ode is connected to the processor memory block.

The solution to these problems has been achieved in a method for ensuring the safety of a fiber-optic communication line, made with long wells connected by a cable duct, containing security control sectors, a main control center, repeaters, security sensors and video cameras with batteries, so that the control center protection by radio channel is connected to repeaters, and the channel of the cable duct, in which the optical cables are laid, is made under the surface of the soil, while The cables are chosen for information transfer, for energy transfer, and for the security system via a cable duct, in each well there is a controller, a limit switch and an internal video camera connected by electrical connections to the battery, which are recharged from photoelectric voltage converters that receive light energy from laser optical a module installed in the first well at the input of the fiber to transmit energy.

The perimeter of each well or part of the wells can be controlled using the well perimeter security system, which contains a sensor optical fiber laid under the ground and connected to a transmitter and signal receiver.

Repeaters are periodically installed at a distance corresponding to the maximum for energy transfer via optical fiber to transmit information about the state of the security system via radio channel to the security control center.

The essence of the group of inventions is illustrated in the drawings (Fig. 1-16), where:

- in FIG. 1 shows a schematic diagram of a fiber optic communication line,

- in FIG. 2 shows a splitter for the first well,

- in FIG. 3 shows a splitter for intermediate and last well,

- in FIG. 4 shows the first well,

- in FIG. 5 shows the intermediate well,

- in FIG. 6 shows an intermediate well with an external video camera,

- in FIG. 7 is a repeater

- in FIG. 8 shows the cable duct,

- in FIG. 9 shows a section B - B in FIG. eight,

- in FIG. 10 shows fiber optic fibers,

- in FIG. 11 shows a diagram of energy transfer through several optical fibers at the same time,

- in FIG. 12 shows a diagram of energy transfer through a single optical fiber,

- in FIG. 13 shows a laser emitter.

- in FIG. 14 shows a well perimeter security system with a signal optical fiber,

- in FIG. 15 is a view A of FIG. 14,

- in FIG. 16 shows the perimeter protection scheme for a well.

Symbols accepted in the description:

fiber optic communication line 1,

cable duct 2

optical cable 3,

soil surface 4,

well 5

cover 6,

security control center 7,

transmitting and receiving device 8,

antenna 9,

optical fiber for energy transfer 10,

splitter 11,

laser optical module 12, (not in each well),

photoelectric voltage converter 13, (in each well),

controller 14,

battery 15,

limit switch 16,

internal video camera 17,

communication lines 18.

external video camera 19, (where there is an external support),

external support 20,

repeater 21.

lead cable 22,

a repeater receiver 23,

communication channel 24,

transmitting device 25,

transmitting and receiving antenna 26,

radio channel 27,

fiber for transmitting information 28,

security fiber 29,

perimeter security system 30,

sensor optical fiber 31,

signal transmitter 32,

signal receiver 33,

transducer 34,

amplifier 35,

processor 36,

memory unit 37,

electrical wires 38.

Fiber optic communication line (FOCL) 1 of FIG. 1 and its security system in a hard-to-reach area contain: a cable duct 2, in which optical cables are laid 3. A cable duct 2 is made under the surface of the soil 4. FOCL 1 has n wells 5 on a site in a hard-to-reach area, including including the first 5 ₁ , intermediate 5 ₂ , 5 ₃ - 5 _n-1 and the last n-th - 5 _n , located at a distance of 0.1-1, 2 km from each other, depending on the location of the fiber-optic communication line 1 The serial numbers of the wells are entered into the RAM of the security system.

If part of the fiber optic communication line 1 is laid in a populated area, then the minimum distances between the wells 5 are accepted.

Each well 5 has a cover 6. The security system includes a security control center 7, which, in turn, contains a transmitting and receiving device 8, to the output of which an antenna 9 is connected.

In remote hard-to-reach areas where it is impossible to supply electricity to power the security system, primarily video cameras, one or more optical fibers are selected to transmit energy 10. At the beginning of the inaccessible area, a splitter 11 is installed in the first well 51 and a laser optical module is attached to it 12, designed to transmit power in the form of light energy.

In the intermediate and last wells 5 ₂ , 5 ₃ ... 5 _{n of the} inaccessible region in each of them, a photoelectric voltage converter 13 is installed, connected to the splitter 11 to receive part of the energy coming from the optical fiber to transmit energy 10.

Splitter (translated from English. - Splitter). Optical splitters and their use in fiber optic communication lines

Fiber optics continues to be one of the most optimal and sought-after media for transmitting data, signals and information over long distances without limiting bandwidth and transmission speed. The construction of fiber-optic communication lines (FOCL) requires the use of specialized active and passive equipment, as well as the use of special tools and devices. A splitter (optical splitter) is a small but necessary device used in the construction of communication networks using optical fiber.

The optical splitter is a passive device that separates the flow of energy transmitted through the optical fiber. This device is passive because power is not required to separate optical power.

Optical splitters have long been successfully used in practice in the construction of trunk and sub-trunk lines in hybrid fiber-coaxial networks (Hybrid Fiber and Coaxial) used to distribute and transmit a television signal in cable television networks. Optical splitters found even greater application with the creation in the 90s and the development of PON (Passive Optical Network) technology, which has now become popular and affordable.

Optical splitters according to the number of inputs and outputs are divided into X-shaped (several inputs and several outputs) and Y-shaped (one input and several outputs). The simplest X-shaped optical divider has two inputs and two outputs (the so-called 2 × 2 optical splitter). The simplest among the Y-shaped optical dividers is an optical splitter, which has one input and two outputs (the so-called 1 × 2 optical splitter). Y-shaped splitters are called power dividers. Y-shaped are divided into two types: symmetric and asymmetric. Symmetrical Y-shaped optical dividers, divide the optical power between the outputs evenly. Asymmetric optical dividers allow you to split the optical power in a certain proportion.

Specifically, in the proposed technical solution, Y-shaped splitters 11 are used for the first well 51 (Fig. 1 and 2) with two inputs and one output, and for the intermediate and last n-th well with one input and two outputs (Fig. 1 and 3 )

In all the wells 5 of the hard-to-reach section of the fiber-optic communication line 1, a controller 14 is installed (for controlling all security devices), to which the battery 15 is attached, a limit switch 16 is installed under the cover 6, which is designed to turn on the internal video camera 17 installed in each well 5. The controller 14, the limit switch 16 and the internal video camera 17 are interconnected by communication lines 18 for energizing and controlling safety devices.

Near some wells 5, an external video camera 19 can be installed.

An external video camera 19 can be installed in the presence of external supports 20. both natural, such as trees, and artificial, such as poles, fences and walls of buildings.

To transmit information about the security status over a considerable distance in places where there are no problems with electricity, for example, in settlements, repeaters 21 can be installed (Fig. 7), to which from the nearest well 5 a lead-in cable 22 is connected to the receiver of the relay 23, which is connected by a communication channel 24 to a transmitting device 25, to the output of which a transmit-receive antenna 26 is connected to transmit information via radio channel 27.

Repeaters 21 must be installed in the absence of settlements and power lines after 70-80 km. This is the limit distance over which energy can be transmitted over the optical fiber. In this case, the power consumption of the repeater 21 and the next section of the fiber optic link 1 can be provided by the use of diesel generators (in Fig. 1-16, diesel generators are not shown).

In FIG. 8-10 shows the structure of FOCL 1 containing optical fibers for various purposes. The optical cable 3, in addition to the optical fiber (s) for transmitting energy 10, contains fibers for transmitting information 28 (the main purpose of the fiber optic link) and security system fibers 29 for transmitting information about the security status of the fiber-optic communication line 1.

In FIG. 11 shows a diagram of energy transmission through several optical fibers 10 at the same time, which can be applied if energy cannot be transmitted through one optical fiber 10 or for duplication of security systems.

In FIG. 12 shows a simplified diagram of the transfer of energy through one optical fiber 10 to all wells 5.

In FIG. 13 shows a laser optical module 12.

Fiber-optic communication line 1 (Fig. 14-16) is equipped with a perimeter security system for wells 30, made under the ground 4 around well 5 to control the passage of intruders to well 5. It is preferable to equip all wells 5 with such systems.

The perimeter security system for wells 30 includes a sensor optical fiber 31 laid under the ground around well 5, a signal transmitter 32, a signal receiver 33, a converter 34, an amplifier 35, a processor 36, and a memory unit 37 (Figs. 14-16).

A signal transmitter 32 is connected to the input of the sensor optical fiber 31, and a signal receiver 33 is connected to the output. The output from the signal receiver 33 is connected to the input of the converter 34. The converter 34 converts the optical (light) signal into an electric signal for amplification, processing, and analysis. The output from the converter 34 is connected to the input to the amplifier 35, and the output from the amplifier 35 is connected to the input to the processor 36. The output from the processor 36 is connected to the input to the controller 14. A memory unit 37 is connected to the second input to the processor. The memory unit 37 contains information on the control algorithm of the security system of the perimeter 30 and the serial number of the well 5 (Fig. 14-16).

It is known that fiber-optic cables, usually used to transmit information, can also be used as sensors for perimeter security systems. Deformation of an optical fiber changes its optical parameters and, as a result, the characteristics of the radiation passing through the fiber. Due to the specificity of the physical principles used, fiber-optic systems are characterized by a very low susceptibility to electromagnetic interference, which allows them to be used even in adverse electromagnetic environments.

An optical fiber in the general case is a coaxial fiber. Light propagates along the central part (core) of the fiber. A transparent shell adheres to the fiber core, which has a lower optical refractive index than the core. Light propagating at an angle to the axis of the fiber is reflected from the interface between the core and the sheath and is concentrated in the central part of the fiber. An external opaque coating serves to mechanically protect the cable.

Miniature semiconductor lasers or LEDs are typically used as a radiation source. An optical receiving module is installed at the cable output, which converts the optical signal into an electrical one. During deformation or vibration of the fiber, the conditions for the propagation of light or its internal reflection change, as a result of which the phase and spatial characteristics of the beam at the output of the cable undergo changes. These changes are recorded by the photodetector and processed by the signal analyzer.

Fiber optic fibers are divided into multimode and single mode. The core diameter of multimode fibers is typically 50-100 microns. A large number of types of waves (modes) with various geometric parameters simultaneously propagate along such a fiber. These rays experience multiple reflections from the boundary between the core and the shell, which leads to a noticeable attenuation of the signals.

The core diameter of single-mode fibers is not more than 10 microns. In such a waveguide, only one type of wave (mode) can propagate, and the damping of light here is substantially less than in multimode fibers.

In fiber-optic security systems, various methods for recording intrusion signals are used:

Method for detecting intermode interference A semiconductor laser usually generates dozens of modes that are close in frequency (spectral lines) with a certain energy distribution over the radiation spectrum. If a multimode fiber optic cable is subjected to mechanical stress, then the radiation spectrum recorded by the receiver changes at its output, which allows the cable deformation to be detected.

Spectrum-structure registration method The so-called spectrum-structure, which is an irregular system of light and dark spots, is observed at the output of the optical fiber. With strains or vibrations of the fiber, the spectrum-structure of the radiation undergoes changes. To detect cable deformations, spatially sensitive photodetectors are used here.

Microstress method

This technology involves the use of two separate single-mode optical fibers through which laser radiation propagates. At the far edge of the zone, the interference of both beams is carried out in a special optical module. If an optical cable installed underground, undergoes mechanical effects (for example, changes in pressure from a passing person), then the conditions for the propagation of radiation through both fibers change, and the dynamics of the interference image in the optical module can detect the intrusion.

The interference method with localization of the invasion site.

This scheme is a “fiber optic” version of the classical Mach – Zander interferometer. The composition of the extended sensor includes three separate fibers of a multicore optical cable. The two upper fibers perform the function of sensitive elements: they are fed by radiation from a semiconductor laser operating in a continuous mode. The third (output) fiber is used to transmit signals to the system analyzer from the terminal optical module. The radiation source is located in the analyzer block, from it the laser radiation is fed through a passive fiber to the initial module. In this module, the radiation is split into two beams, which are fed into two sensitive fibers. On the terminal module, interference of both beams occurs. If both arms of this interferometer are in an unperturbed state, then the interference pattern on the terminal module remains unchanged. In this case, the signal transmitted from the terminal module through the output optical fiber to the analyzer does not have a variable component. During cable deformations or vibrations, the optical path difference in sensitive fibers (i.e., the arms of the interferometer) changes, and the terminal module registers the variable component of the signal, passing it to the analyzer. A specific feature of this interference system is that it determines the relative time delay of the recorded signals at both arms of the interferometer. This allows you to determine the place of intrusion into the system with an accuracy of several meters.

Coherent optical time domain reflectometry reflectometry technology.

Another technology, which has appeared relatively recently, uses the principles of C-OTDR. The full name of this technology is Coherent Optical Time Domain Reflectometry - or time-resolution coherent optical reflectometry. This technology assumes that a fiber cable is connected to the controller, into which laser radiation is supplied. Each element of the fiber cable partially reflects the radiation towards the controller. If the cable is subjected to deformations or vibrations, the characteristics of the reflected light change and the system registers an alarm. The efficiency of the system increases significantly if regular inhomogeneities of the refractive index with a spatial period comparable to the wavelength of the laser radiation are specially created in the fiber, i.e. conditions for the so-called Bragg scattering are formed. This technology allows you to measure the delay time of the reflected signal and obtain information about the place where violations of the sensor state occur, i.e. about the place of the invasion.

All of these systems are very complex and therefore have a very high cost. Given the large length of FOCL 1, which runs throughout the country and a huge number of wells 5, this problem is of great importance. The simplest, minimum-energy consuming and maintenance-free security scheme for the well perimeter 5 has been proposed (Figs. 14-16).

For the transfer of energy, any existing optical fibers can be used, including free fibers, while it is possible to simultaneously transmit the control information of the security system and energy over the same optical fiber.

SECURITY SYSTEM OPERATION

The security system of the fiber optic communication line is as follows (Fig. 1).

When you try to open the cover 6 of the well 5, the limit switch 16 is activated and closes the power circuit of the internal video camera 17 from the battery 15. The internal video camera 17 transmits video information through the optical security fiber 29.

In the presence of an external video camera 19, a video signal is also transmitted from this video camera.

Repeaters 21 are installed every 70-80 km to transmit information about the status of the security system over the air to the main control center.

The interval for the installation of repeaters 21 was determined by the maximum possible distance for the transmission of optical energy through the optical fiber without significant losses, provided that it was removed in the intermediate wells 5 for powering the internal video cameras 17.

The use of the perimeter security system for wells 5 makes it possible to detect the intruder’s penetration to the well 5 and the penetration site with an accuracy of several meters (determine the well identification number) and transmit this information (Fig. 16) from the sensor optical fiber 31 to the receiving device 33, then through the converter 34 and an amplifier 35 to a processor 36 that analyzes the information. The processor 36 transmits it to the controller 14 and then through the optical fiber of the security system 29 and the supply cable 22 to the entrance to the nearest relay 21 to the receiver of the relay 23 (Fig. 7), then to the transmitting device 25, then to the transmitting and receiving antenna 26 and via radio channel 27 to the security control center 7 (Fig. 1).

The application of the invention allowed:

reduce energy consumption by security systems including video cameras,

- ensure the transfer of energy to power the security system equipment in hard-to-reach areas of the country,

- to ensure the protection of the perimeters of wells with minimal costs for equipment and operation and with relatively low energy consumption,

- provide control over unauthorized opening of the covers of wells and exclude cases of vandalism and acts of sabotage.

Claims (10)

1. The security system of a fiber-optic communication line, made in an inaccessible area extended with n wells connected by a cable sewer channel, comprising security control sectors, a security control center, repeaters, security sensors and video cameras with batteries, divided into sections, characterized in that the center security control by radio channel is connected to the relay, and security sensors and video cameras via an optical cable for the security system are connected to the relay, the cable channel The sewerage, in which the optical cables are laid, is made under the surface of the soil, while the optical cables are selected for information transfer, for energy and security systems, in each well there are: a controller, a limit switch and an internal video camera connected by electrical connections to the battery, the first well of the optical fiber section of a hard-to-reach area for energy transfer to the intermediate and the last n-th well is equipped with a splitter to which a laser optical module is connected, in the intermediates and final n-th pit through the splitter to the optical fiber connected to the photoelectric voltage converter connected by electrical wires to the battery. 2. The security system of the fiber-optic communication line according to claim 1, characterized in that the Y-shaped splitter with two inputs and one output is used for the first well, and the Y-shaped splitter with one input and two for intermediate and n-th wells exits. 3. The security system of the fiber-optic communication line according to claim 1, characterized in that outside the part of the intermediate wells, if there are natural supports, external video cameras are installed, connected by communication lines to the controller in the nearest well. 4. The security system of the fiber optic communication line according to claim 1, characterized in that the wells are made in 0.1-1.2 km. 5. The security system of the fiber-optic communication line according to claim 1, characterized in that along the FOCL section in the inaccessible area, repeaters are installed every 70-80 km to transmit information about the status of the security system over the air to the security control center. 6. The security system of the fiber-optic communication line according to claim 1, characterized in that a well perimeter security system is implemented near each well or part thereof. 7. The security system of the fiber-optic communication line according to claim 6, characterized in that the well perimeter security system comprises: a sensor optical fiber laid underground under the well, a signal transmitter, a signal receiver, a converter, an amplifier, a processor and a memory unit, In this case, the signal transmitter is connected to the input to the sensor optical fiber, and the signal receiver is connected to the output, the output from the signal receiver is connected to the input to the converter, the output of which is connected to the input to the amplifier, and the output from the amplifier is connected to the input to the processor, the output from the processor is connected to the input to the controller, a memory block is connected to the second input to the processor. 8. A method for ensuring the security of a fiber-optic communication line made with long wells connected by a channel of cable ducts, which comprises security control sectors, a main control center, repeaters, security sensors and video cameras with batteries, characterized in that the security control center the radio channel is connected to the repeaters, and the cable duct, in which the optical cables are laid, is made under the surface of the soil, while the optical cables are selected for In order to transmit information, to transfer energy, and for a security system by a cable duct, in each well there is a controller, a limit switch and an internal video camera connected by electrical connections to the battery, which are recharged from photoelectric voltage converters that receive light energy from a laser optical module installed in the first well at the entrance of the fiber to transmit energy. 9. A method for ensuring the safety of a fiber-optic communication line according to claim 8, characterized in that the perimeter of each well or part of the wells is controlled by a well perimeter security system containing a sensor optical fiber laid underground and connected to a transmitter and a signal receiver. 10. A method for ensuring the security of a fiber-optic communication line according to claim 8, characterized in that at a distance corresponding to the maximum for transmitting energy through the optical fiber, periodically installed relays for transmitting information about the state of the security system over the air to the security control center.

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