EP4186179A1

EP4186179A1 - Non-intrusive traffic monitoring in optical fiber networks

Info

Publication number: EP4186179A1
Application number: EP21748670.3A
Authority: EP
Inventors: António José BISCAIA FRANCO; Luis João DO ROSÁRIO FERREIRA RIBEIRO DE CARVALHO
Original assignee: Nos Technology Concepcao Construcao E Gestao De Redes De Comunicacoes SA
Current assignee: Nos Technology Concepcao Construcao E Gestao De Redes De Comunicacoes SA
Priority date: 2020-07-24
Filing date: 2021-07-21
Publication date: 2023-05-31
Also published as: WO2022018670A1

Abstract

The present invention describes a real-time monitoring system for passive optical fiber networks for use under DWDM, GPON, XGPON, technologies, or others, in a permanent and non-intrusive manner. The system developed allows, in a non-limitative manner, the bidirectional real-time monitoring of at least 12 optical channels simultaneously. The system developed comprises the use of two components, a reading module, and a user device that is technically adapted to proceed with reading the information originating from the reading module, which will make available to the user the operational state of each optical fiber analyzed. The communication between the devices can comprise the use of NFC technology or other that is technically equivalent. Without being considered as a limitation to the functionality of the system, this can contemplate the use of local or remote physical energy sources, the latter resorting to power transmission by the proximity of the user device.

Description

DESCRIPTION

"NON-INTRUSIVE TRAFFIC MONITORING IN OPTICAL FIBER

NETWORKS"

Technical domain

The present invention describes a real-time monitoring system for passive optical fiber networks for use under DWDM, GPON, XGPON, technologies, or others, in a permanent and non-intrusive manner.

Background

In telecommunications networks, namely the PON fiber optic passive networks, the most usual ones nowadays, the capacity of permanent monitoring of the operational state thereof is extremely important. This capacity allows, above all, and in cases of failure in the service supply to the clients, to improve the capacity and speed in the response for the solution to problems and damages in the PON networks.

Currently, there are equipments that use the macrocurvature technique for the detection of the existence of an active signal in the fiber. Document US5708499 discloses a device which may be used to detect the presence of light in optical fibers in a unique manner while the optical fiber is in use, or to introduce light into an optical fiber. The device includes an identifier chip, and an associated complementary shaped plate, each of which employ both microbending and macrobending portions. The chip and the plate are formed by a single piece of material, although only the chip must be formed of an optically transmissive material. In use, the chip is pressed in the direction of the plate with an optical fiber therebetween. The deformation of the fiber caused by the stress exerted by the chip and the plate will cause detectable light to be emitted through the chip if the fiber is alive.

Summary

The present application describes a non-intrusive optical fiber traffic monitoring system, characterized by comprising at least one reading module comprising an upper surface comprising a compression boss, and a lower surface comprising a rear retention array and a front retention array for fixation of the fiber; and at least one printed circuit board, physically adapted and installed in the reading module, making a signal available at the exit thereof; at least one multiplexer linked to the exit of the referred at least one channel, combining the signals originating therefrom; at least one processing unit, adapted to receive, treat and retransmit the combined signals originating from at least one multiplexer; wherein the upper surface by the action of the mechanical union with the lower surface and of the compression boss, compresses the optical fiber placed between the rear retention array and the front retention array.

In one proposed embodiment, the at least one reading channel comprises an ascending reading channel and a descending reading channel.

In another embodiment, the at least one processing unit comprises a bidirectional data storage and communication system. In yet another embodiment, the reading module comprises at least one of at least one battery and/or at least one external power supply to guarantee the working of the referred module.

In another embodiment, the at least one external power supply comprises at least one electric power supply and/or one supply originating from the electro-magnetic field generated by the bidirectional data communication.

In another embodiment, the ascending reading channel comprises a photodiode, an amplifier and a schmitt trigger logic gate.

In another embodiment, the descending reading channel comprises a photodiode, an amplifier and a schmitt trigger logic gate.

In another embodiment, the photodiode of the ascending reading channel is installed in the proximity of the rear retention array and the photodiode of the descending reading channel is installed in the proximity of the front retaining array.

In another embodiment, the photodiode of the ascending reading channel captures the ascending signal flow in the interior of the fiber and the photodiode of the descending reading channel captures the descending signal flow in the interior of the fiber.

In another embodiment, the reading channel comprises an antenna that is interconnected to the processing unit to optimize the reception of electric energy and the transmission of data by means of the bidirectional data communication.

In another embodiment, the reading module comprises the use of a physical system for visualizing the traffic flow inside the core of the fibers to be monitored.

In another embodiment, the bidirectional data communication comprises the use of at least one of NFC and/or RFID and/or Bluetooth technology and/or another technically suitable.

In another embodiment, the system further comprises a user equipment equipped with NFC and/or RFID and/or Bluetooth technology and/or other that is technically suitable to carry out the bidirectional data communication with the processing unit in the reading module.

In another embodiment, the user equipment is technically adapted to carry out the energy supply for the reading module.

In another embodiment, the user equipment is adapted to receive the information from the at least one intended reading channel, identifying whether the data flow in the interior of the fiber is a descending, ascending, ascending and descending, or without optical signal.

In another embodiment, the reading module is physically adaptable to any type of equipment existing in an optical fiber network, namely OLT (Optical Line Terminal), ONT (Optical Network Terminal), ODF (Optical Distribution Frame), joints, distribution points, among others. In another embodiment, the compression in the optical fiber caused by the compression boss introduces insertion losses lower than ldB.

In another embodiment, the photodiodes guarantee the reading of a range of wavelength values comprised between 1300nm and 1600nm.

In another embodiment, the compression in the optical fiber caused by the compression boss causes a radius of curvature in the fiber which comprises values between 6mm and 15mm, in a preferred embodiment having 9mm.

In another embodiment, the compression boss comprises a width of 3mm and a height of 2mm relative to the face of the upper surface, introducing a compression having sensitively 1mm height in the fiber, and, the distance between the rear retention array and the front retention array is sensitively 12mm.

Brief description

Ihe present invention describes a real-time monitoring system for passive optical fiber networks for use under Dense Wavelength Division Multiplexing (DWDM), Gigabit Passive Optical Networks (GPON), Ten-Gigabit Passive Optical Networks (XGPON), or other, in a permanent and non-intrusive manner.

The system developed allows, in a non-limitative manner, the bidirectional real-time monitoring of at least 12 optical channels simultaneously. The user may visually validate the working state of at least one optical fiber, by means of the visual indication present in the reading module, or by means of the user device by means of an APP specifically developed for this purpose, thus determining whether this fiber, or fibers, is connected to the active equipment and with the flow of traffic running through its core. This operation is carried out without existing the need to turn off connectors and/or resort to more burdensome and intrusive procedures, not only for the passive optical network (PON), but also for the final users of the service.

The bidirectional monitoring is guaranteed by means of the use of a double sensor for simultaneous measurement of the flow of traffic in both directions of the fiber core under analysis.

The monitoring system developed is formed by two components, one reading module and a user equipment for reception and presentation of the information.

The working principle of the system developed is based on the concept of optical fiber macrocurvature (FO), which allows deforming a fiber core and extracting a small part of the optical signal present in the FO, in case this is connected to an active emitter and/or receptor equipment, enabling this fraction of removed signal to be subsequently detected by means of the photodiodes installed in the reading module created and adapted for this effect.

The technological resource used for the validation of the working state of the optical fibers (FO), is grounded on the use of a smartphone or tablet, or other, technically adapted, armed with Near Field Communication (NFC) technology and with a native application for reading tags NFC. This, also known as user equipment, can be responsible for the feeding of the reading module by means of the transmission of the field effect energy available in the connection carried out by NFC between the two modules and by the existing external antenna. The technology used for the communication between the reading module and the user equipment is not exclusive to the NFC, whereby there may be used the Radio-Frequency IDentification (RFID), Bluetooth, or other type of technology with identical working characteristics, allowing unlimited and independent autonomy, without the need to consume energy in a passive manner.

The energy supply of the reading module, in a non-exclusive and limitative manner, is characterized by presenting modularity according to the need of the user or final operator, and may be carried out by resorting to batteries or local accumulators in the referred module, as well as using local energy supplies.

This modularity and adaptability to the client's installation needs enables, and in case of need or limitation of the installation location, resorting to the energy transfer system. This, apart from minimizing the energy dependence of the reading module, which by means of the suppression of the resource to batteries, or other permanent external energy sources, allows making the system energetically independent, further enables the elimination of the need for equipment maintenance operations, making it practically nonexistent, which is considered an innovation factor in this type of monitoring equipment.

The permanent installation of the reading module in the equipment which it is intended to monitor, for example, and in a non-limitative manner, in an Optical Distribution Frame (ODF), allows that, together with the use of the smartphone in the proximity of the referred equipment, it is possible to determine the working state of the fibers, by means of a rapid reading or observation on the part of the user, not being necessary the installation and/or use of costly additional equipment and which is difficult to adapt for carrying out this task, thus minimizing the checking times of these operations.

The detection of the optical signal present in the FO is reached by means of the extraction of a fraction of light, inputed by the active network equipment, and which traverses the core, not existing the need to interrupt the existing connection. In this manner it is possible to make the distinction between active fibers (with optical signal) and inactive fibers (without optical signal) in a non-intrusive manner. Therefore, there is no longer the need to turn off the circuits with active clients to validate the presence of signal in the fibers, introducing the concept of non- intrusive installation and monitoring.

Part of the light which propagates in the FO, can be removed applying a slight curvature in the fiber, providing a deformation in the core, allowing part of the light to exit by the insulating sheath. The curvature can be slight (microcurvature) or accentuated (macrocurvature) according to the need of the signal to be extracted. Whereby the smaller the curvature radius plus signal that is extracted from the fiber, however, the larger will be the insertion losses, that is, the larger will be the attenuation of the connection. The microcurvature technique was excluded from the development process since the FO used presented a PVC coating which renders unviable the correct detection of the signal. Thus, the adopted solution is grounded on the macrocurvature technique which consists in applying a slight curvature to the fiber to deform the core, and allow that part of the optical power be extracted.

To determine the theoretical values of attenuation associated to the curvature radius of the optical fibers, several comparative studies were carried out between theoretical values and the practical/measured ones. For one of the systems developed, there were used as study object the single-mode step index optical fibers and cable which nominal wavelength is close to 1550nm. These follow the technical specifications of the G.652, G.653 and G.657 norms of the ITU-T organization called Dispersion-shifted fibers, which have a modified wave dispersion guide. These are fibers where the refractive index of the core is altered, to ally the benefits of the wavelengths of 1310nm and 1550nm. While in the region of the wavelength of 310nm, there is verified null chromatic dispersion, at 1550nm there is the benefit of lower attenuation values. The measurements were carried out based on the guidelines of IEC norm 60793-1-47, using as study reference an optical fiber with the previously mentioned characteristics.

The tests carried out allowed to conclude that the difference between theoretical and practical values is residual, there being verified solely larger differences as the curvature radius applied to the optical fiber is reduced. This deviation is beyond the interest zone of the project (above 1 dB), not being therefore a problem to be considered. From the theoretical point of view, from the power injected in a fiber, Pi, part will be extracted, P_e, and the remaining, which is referred to as exit power, P₀, will continue to traverse the core until its destination.

By definition of insertion loss, Insertion Loss (IL), is translated into the relation between the input power and the output power of the fiber, which is given by:

The derivation loss, Derivation Loss (DL), means the relation between the inserted power and the extracted power.

DP Pi/Pe ^ ^^[dB] ^[dBm]^— ^e[dBm]

The derivation loss can be obtained indirectly by means of the IL, assuming that the losses result essentially from the power extracted from the fiber, that is,

P ^re = P ^r i - P ^ro

Which will give rise to

The power detected by the photodiodes is a small part of the extracted power, from the active area of the photodiode, the angle and the relative location between the fiber and the photodiode. In order to simplify the problem, all the factors are aggregated in a b parameter which will be empirically determined, being preferably maximized. Therefore, the power P_d detected is given by

P_d = b^r=b XDL x P_t

The reading module, as previously indicated, comprises the use of photodetectors to determine the FO with active signal.

There currently exist in the state of the art several types of photodetectors, wherein we find the photodiodes PIN and APD, phototransistors, etc. However, only the PIN and APD photodiodes present suitable characteristics for application in telecommunications, namely in FO PON networks.

The PIN photodiode is a photodiode having an intrinsic layer placed between the type P and N material. Ideally a PIN photodiode should generate an electron hole pair in the depletion region for each incident photon. However, in practice this is not observed. The efficiency of the optical- electric conversion designated by quantum efficiency (Quantum efficiency) is lower than 100%. Another parameter used to characterize the photodiodes is the responsivity, Rx, which relates the electric current at the exit of the photodiode, I_p, with the incident optical power, P, wherein

Rx= Ip / P

Another type of photodetector that is commonly used in optical communications is the avalanche photodiode or avalanche photodiode (APD). In this one, the electric current generated by each incident photon is amplified in the interior of the device itself. This gain is obtained by means of the physical process of avalanche multiplication. However, the avalanche multiplication requires a more intense electric field than the PIN photodiode. For this reason, the APD photodiode is polarized with inverse tension quite superior to that used in the PIN. The responsivity of an APD photodiode is given by:

RA_APD=M X R_\ where M is the multiplication factor by avalanche, which typically can vary between 10 and 100.

The wavelengths used in the Gigabit Passive Optical Network (GPON) and Synchronous Digital Hierarchy (SDH) networks are between 1310nm and 1550n , the most suitable photodiodes are those with intrinsic layer Indium gallium arsenide (InGaAs) which has a responsivity higher than 60% between 1200nm and 1700nm. Considering these parameters, the choice of the most suitable photodiode for the effect resulted in a reading range covered between the 1300nm and the 1600nm. Thus, it is possible to obtain an agnostic measurer, allowing to carry out and obtain optical power measurements independent of the network used.

A photodiode when exposed to a light source, transforms this light in intensity, Ip, which depends on the incident luminous power, P. However, the working range of the photodiodes is limited superiorly by the saturation (maximum current that the photodiode supplies) and inferiorly by the noise of the photodiode itself (noise floor).

Intrinsically, the photodiode further contains parasitic elements such as the junction capacitance, Cj, and the shunt resistor which are in parallel with the current source, and the resistance of the terminals, Rs. The noise produced by the photodiode is an important characteristic in the measurement of the low power signals, and which in most cases is equivalent to a noise power (NEP) de 4 fW/VHz. Theoretically with this level of noise power in a lHz band and integrating for 0,5 seconds, it is possible to detect signals with a power above the 4fW, that is, signals superior to -143dBm. However, the noise level generated by the photodiode (NEP) is typically much lower than the thermal noise generated by the resistive elements of the circuit, that is, the circuit conversion load/signal measurement. For example, the noise level for a lHz band and at a temperature of 25°C produced by the shunt resistor, Rs, of 2GQ and the junction capacity, Cj, of lOpF of the photodiode with a load of 50 W is equal to 7,5 pW which is equivalent to -81,2 dBm.

On the side of the passive network PON, the minimum power in the fiber on the operator's side is approximately 2dB (considering 1 dB of loss distributed by the connectors and fusions along the trajectory to the client and 1 dB more margin) above the sensitivity of the optical receptor, that is, -30 dBm for class C+ and -26 dBm for class B+.

The output signal produced by a photodiode can be measured by tension or current, the latter one being the most used, since it presents a behavior that is more linear, little offset and a high bandwidth.

The purpose of this development for applying in telecommunication FO networks, aims above all:

- To power and capacitate the PON equipments, of a monitoring system in real time of the working state of each FO; - Efficiently foil entry errors, improving the update;

- Optimize and reduce the times for operational analysis of the equipment on the part of the operators and/or technicians;

- Foil in a more efficient manner damages to the PON network;

- Minimize costs in monitoring systems;

Minimize the need for discrete costly equipment for verifying the connectivity of the FOs.

Among other advantages, the system developed further allows the adaptation and assembly in common equipment that is already existent in the optical fiber networks currently in use; the signalization is local and can be visible; it does not depend on the type of connector used; and can be energetically independent of a physical local power source.

Brief Description of the Figures

For an easier understanding of the present application there are figures attached which represent embodiments that, however, do not intend to limit the technology herein disclosed.

Figure 1 illustrates schematically the block diagram of the monitoring system reading module (100), wherein:

101 - channel 1;

101+n - channel n;

1010 - ascending reading channel (upload); 1011 - ascending channel photodiode;

1012 - ascending channel amplifier

1013 - logic gate - sch itt trigger - of the ascending channel

1020 - descending reading channel (download);

1021 - descending channel photodiode;

1022 - descending channel amplifier;

1023 - logic gate - schmitt trigger - of descending channel 1030 - multiplexer;

1040 - microcontroller;

1050 - supply / energy source;

1060 - bidirectional data communication system with or without wires.

Figure 2 illustrates a working mode of the reading module (100) of the monitoring system relative to an independent channel, in this case channel 1 (101), the concept however, being applied transversally to the n next channels (101+n), wherein:

200 - optical fiber;

1011 - ascending channel photodiode;

1021 - descending channel photodiode;

300 - supper surface;

301 - compression boss;

400 - lower surface;

401 - rear retention array;

402 - front retention array;

500 - FO connector.

Figure 3 illustrates in detail the working of the reading module (100) by action of the ascending channel photodiode (1011), caused by the ascending data flow toward the active equipment of the center. The references identify:

200 - optical fiber;

1011 - ascending channel photodiode;

300 - upper surface;

301 - compression boss;

400 - lower surface;

401 - rear retention array;

402 - front retention array;

Figure 4, similarly to the previous figure, illustrates in detail the working of the reading module (100) by means of the action of the descending channel photodiode (1021), caused by the descending flow of data toward the active equipment of the final user. The references identify:

200 - optical fiber;

1021 - descending channel photodiode;

300 - upper surface;

301 - compression boss;

400 - lower surface;

401 - rear retention array;

402 - front retention array;

Figure 5 illustrates a possible implementation form of the reading module (100), with application developed for 12 reading channels, wherein:

200 - optical fiber;

1011 - ascending channel photodiode;

1021 - descending channel photodiode;

400 - lower surface;

500 FO connector. Figure 6 illustrates the same form of implementation of Figure 5, with the inclusion of the upper surface (300) applied to the system (100).

Figure 7 illustrates a possible implementation form of the monitoring system (100) applied to an ODF.

Description of embodiments

With reference to the figures, some embodiments are now detailed, which do not intend, however, to limit the scope of the present application.

The monitoring system developed is formed by two components, a reading module (100) and a user equipment, responsible for the transmission of energy, communication, data communication and respective presentation of the information to the user.

For the specific case of developing the reading module (100), the optical systems usually monitored focus mainly over Synchronous Digital Hierarchy (SDH) connection, wherein the transmission frequencies are found within some dozens of GHs, which in the case of the optical measurement of the photodiodes (1011, 1021) by current would make mandatory more exacting specifications for the electronic components. For this reason, in the development, it was opted to carry out the measurement by tension placing the photodiodes (1011, 1021) in the photovoltaic mode. This decision enabled taking advantage of the parasitic capacities of the photodiodes (1011, 1021) to integrate over the time the captured signal, thus relieving the technical specifications of the amplifier which interconnects to the photodiode (1011, 1021). The amplifier (1012, 1022) which interconnects with the photodiode (1011, 1021), so as not to influence the readings, presents an impedance entry superior to the shunt resistance of the photodiode and leakage currents at least ten times lower than the current produced by the photodiode when irradiated with the minimum optical power which it is intended to measure. As basis in the requirements, the operational amplifier (1012, 1022) chosen, presents in the entries a leakage current lower than 20fA, an exit offset lower than 150pV and a typical current consumption of IOmA. In order to maximize the input impedance a non-inverting topology was opted for. The tension gain of the amplifier was defined to detect optical signal levels lower than -20 dBm with an insertion attenuation close to 1 dB (attenuation introduced by the macrocurvature) for which it is necessary a gain superior to 40.

Therefore, and as regards the sensitivity of the reading equipment, namely, the photodiodes (1011, 1021), the reading equipment (100) developed allows detecting the presence of optical signals with powers up to -30dBm, with minimum insertion losses lower than ldB.

Subsequently to the amplification of the signal of the photodiode (1011, 1021), this is converted to the digital format by means of one of the inverting gates (NOT) with Schmitt trigger entry (1013, 1023).

Subsequently to the digitalization of the channels, these will be subsequently sequentially measured by means of double channel multiplexers (1030) the result being stored in the RAM memory of the microcontroller (1040) for later remittance to the user device by means of the bidirectional communication (1060).

The processing of the signal is made by microcontroller (1040) with connectivity carried out by means of the bidirectional communication NFC (1060), which presents the possibility and capacity for self-supplying (1050) originating from the electromagnetic field generated by the NFC connection (1060), which will further provide supply to the remaining components of the reading module circuit (100). In this manner, the fiber reading module (100) works in an independent manner, there not existing the need for a permanent energetic supply source, or resource to a battery.

In one of the proposed embodiments, the external receptor antenna of the NFC implemented in the reading module (100), presents a minimum area of 47mm x 32mm.

With the approximation of a user device with NFC reader to the antenna of the fiber reading module (100), the circuit will be automatically fed, providing the sequential reading of the state of the channels (101, 101+n), which will subsequently be sent by NFC (1060).

The working state of each channel (101, 101+n) is codified according to the following values:

- Ascending optical signal (upload) - code 1;

- Descending optical signal (download) - code 2;

Descending and ascending optical signal (upload and download) - code 3;

- Without optical signal present - code 0

The mechanical solution developed for the creation of the macrocurvatures in the fibers is constituted by mechanical elements, a lower surface (400), drafted to support a printed circuit board (PCB) with all the electronics necessary for carrying out the readings and respective transmission to the user equipment, which incorporates a rear retention array (401) and a front retention array (402), and, an upper surface (300) which incorporates a compression boss (300) responsible for deforming the fiber at the reading location. Several solutions were developed which contemplate different curvature radius in the region of interest, which comprise values between 6mm and 15mm, whereby, the curvature radius of 9mm among the arrays (401, 402) introduces an insertion loss value approximately of 1 dB. This slight attenuation does not significantly interfere with the signals transmitted, since it is found within the parameters used by the telecommunications operators which allows them to guarantee the delivery of the service to the client without affecting the global performance of the connection.

The integration time, or measure, of the reading module (100), depends inversely on the optical power, that is, the lower the power in the fiber the longer will be the time necessary to obtain a reliable measure. The measurement time, however, for the application developed never exceeds one second duration even for optical powers of -30 dBm.

According to Figure 6, it is possible to visualize the upper surface (300) that works as a lid for the lower support (400) and respective arrays (401, 402), sealing the compartments where the photodiodes are installed (1011, 1021). Considering the high sensitivity of the photodiodes (1011, 1021) to visible light, it has become obligatory to guarantee an optical insulation of the reading chamber of each reading channel to avoid external interferences of the ambient light, or adjacent fibers, thus guaranteeing that the ambient light does not alter the measurements carried out in each channel.

This optical insulation is guaranteed by the perfect mechanical fitting between the upper (300) and lower (400) surfaces.

The reading module (100) described allows simultaneous monitoring of the activity in multiple fibers and in both directions of traffic: ascendent (upload) and descendent (download).

The equipment indirectly measures, by means of the macrocurvature technique, the optical power which flows in the fiber being independent of the protocol used in the network and optical signal wavelengths. Thus, there existing traffic, and regardless of the direction thereof, the same is detected in real time when of the interaction of the user equipment with the module (100).

The reading module (100) is constituted by, in one of the proposed embodiments, multiple monitoring channels (101+n) regardless of whether they interconnect to a processing unit (1040), or microcontroller, directly or by means of one or several switching circuits, as exemplified in Figure 1.

Each monitoring channel (101) is characterized by the existence of a mechanical part or compression boss (301), two photodiodes (1011, 1021), two amplifiers (1012, 1022) and two Schmitt-trigger logic gates (1013, 1023). The compression boss (301), existent on the upper surface (300), allows introducing a slight curvature in the optical fiber of each channel (macrocurvature), sufficient to produce a light extraction in the referred fiber, introducing a slight attenuation, or loss of residual insertion, in the optical connection with values lower than 1 dB.

In Figure 2, there is presented in vertical view the physical aspect of the macrocurvature system created by the crushing of the fiber (200) when compressed by the compression boss (300). The macrocurvature in the fiber (200) is possible due to the positioning of the latter in the rear retention array (401) and front (402), which is compressed between both the arrays (401, 402), by the boss (300).

It must be noted that the upper surface (300) equipped with the compression boss (301) can be coupled to the reading module (100) without the need to turn off the optical connection between the emitter and receptor equipment. This functionality is possible due to the low insertion loss, which allows guaranteeing that the equipment execute non- intrusive measurements in the optical fiber network. The photodiodes (1011, 1021) are strategically positioned close to the arrays (401, 402) and on the extremes of the bend caused by the compression boss (301) to maximize the capture of the light originating from the fiber, in both communication directions, such as presented in Figures 3 and 4.

In one of the possible embodiments, the curvature radius of the fiber (200) comprises values between 6mm and 15mm, whereby, a curvature radius of 9mm introduces a loss insertion value of approximately 1 dB. In one of the embodiments proposed the compression boss (301) presents a width of 3mm and a height of 2mm relative to the face of the upper surface (300), introducing a compression of sensitively 1mm height in the fiber (200). The distancing proposed between the rear retention array (401) and the front retention array (402), in one of the proposed embodiments, is sensitively 12mm.

The photodiodes (1011, 1021) are responsible for carrying out the conversion of the photons into electrons, physical process known as photoelectric effect. The quantity of electrons produced by the photodiode depends directly on the quantity of photons received, which can be electrically modelled by a source of current dependent on luminous intensity. Upon receiving fiber photons there is produced a tension to the terminals of the photodiode by way of integration of the optical energy received. After amplification, the electric signal generated by the photodiode is compared with a decision level of a Schmitt- trigger logic gate being thus converted into digital. Each monitoring channel makes available two digital signals which reflect the activity state and direction of the optical signal which flows in the optical channel.

The monitoring of the direction in which the optical signal flows is possible due to the positioning of the two photodiodes (1011, 1021) next to the interior extremities between the two retention arrays (401, 402). Depending on the direction, the signal exits the fiber before or after the curvature introduced by the compression boss (301). Thus, each photodiode is exposed to the optical signal which flows in each direction such as illustrated in Figures 3 and 4.

The present description is not, naturally, in any way restricted to the embodiments presented in this document and a person skilled in the art with average knowledge of the area can foresee many possibilities of modification of the same, without departing from the general idea, such as defined in the claims. The preferred embodiments described above are obviously capable of being combined among them. The following claims additionally define preferred embodiments.

Claims

1. Non-intrusive optical fiber traffic monitoring system (200) comprising at least one reading module (100), which comprises an upper surface (300) with a compression boss (301) and a lower surface (400) comprising a rear retention array (401) and a front retention array (402) for fixation of the fiber (200); and at least one printed circuit board, physically adapted and installed in the reading module (100), comprising at least one reading channel (101), enabling a signal at the exit thereof; at least one multiplexer (1030) connected to the exit of the referred at least one channel (101), combining the signals originating therefrom, at least one processing unit (1040), adapted to receive, treat and retransmit the combined signals originating from the at least one multiplexer (1030), wherein the upper surface (300) by action of the mechanical union with the lower surface (400) and of the compression boss (301), compresses the optical fiber (200) positioned between the rear retention array (401) and the front retention array (402).

2. System according to the previous claim, wherein the at least one reading channel (101) comprises an ascendent reading channel (1010) and a descendent reading channel (1020).

3. System according to any of the previous claims, wherein the at least one processing unit (1040) comprises a system for storage and bidirectional data communication (1060).

4. System according to any of the previous claims, wherein the reading channel (100) comprises at least one battery and/or at least one external power supply (1050) to guarantee the working of the referred module.

5. System according to any of the previous claims, wherein the at least one external power supply (1050) comprises at least one of an electric power supply and/or a supply originating from the electromagnetic field generated by the bidirectional data communication (1060).

6. System according to any of the previous claims, wherein the ascending reading channel (1010) comprises a photodiode (1011), an amplifier (1012) and a schmitt trigger logic gate (1013).

7. System according to any of the previous claims, wherein the descending reading channel (1020) comprises a photodiode (1021), an amplifier (1022) and a schmitt trigger logic gate (1013).

8. System according to any of the previous claims, wherein the photodiode (1011) is installed in the proximity of the rear retention array (401) and the photodiode (1021) is installed in the proximity of the front retention array (402).

9. System according to any of the previous claims, wherein the photodiode (1011) captures the ascendent signal flow in the interior of the fiber (200) and the photodiode (1021) captures the descendent signal flow in the interior of the fiber (200).

10. System according to any of the previous claims, wherein the reading module (100) comprises an antenna interconnected to the processing unit (1040) to optimize the reception of electric energy (1050) and the transmission of data by means of the bidirectional data communication (1060).

11. System according to any of the previous claims, wherein the reading module (100) comprises the use of a physical system for visualization of the traffic flow in the interior of the core of the fibers to be monitored.

12. System according to any of the previous claims, wherein the bidirectional data communication (1060) comprises the use of at least one technology NFC and/or RFID and/or Bluetooth and/or other technically suitable.

13. System according to any of the previous claims, additionally comprising a user equipment armed with technology NFC and/or RFID and/or Bluetooth and/or other technically suitable for carrying out the bidirectional data communication (1060) with the processing unit (1040) of the reading module (100).

14. System according to any of the previous claims, wherein the user equipment is technically adapted to carry out the power supply (1050) to the reading module (100).

15. System according to any of the previous claims, wherein the user equipment is adapted to receive the information from at least one intended reading module (101), identifying whether the data flow in the interior of the fiber (200) is an ascendent, descendent, ascendent and descendent, or without optical signal.

16. System according to any of the previous claims, wherein the reading module (100) is physically adaptable to any equipment existing in an optical fiber network (200), namely, Optical Line Terminal, Optical Network Terminal, Optical Distribution Frame, joints, distribution points, among others.

17. System according to any of the previous claims, wherein the compression in the optical fiber (200) caused by the compression boss (301) introduces insertion losses lower than 1 dB.

18. System according to any of the previous claims, wherein the photodiodes (1011, 1021) guarantee the reading of a range of wavelengths comprised between 1300nm and the 1600nm.

19. System according to the previous claims, wherein the compression in the optical fiber (200) caused by the compression boss (301) provokes a curvature bend in the fiber (200) which comprises values between 6mm and 15mm, in a preferred embodiment with 9mm.

20. System according to the previous claims, wherein the compression boss (301) comprises a width of 3mm and a height of 2mm relative to the face of the upper surface (300), introducing a compression of sensitively lrrm height in the fiber (200), and the distance between the rear retention array (401) and the front retention array (402) is sensitively 12mm.