Exfo Inc.

Michel Leclerc

Stephane Perron

Mario L'Heureux

Pascal Gosselin-Badaroudine

Gang He

Stéphane Perron

Eric Thomassin

Jimmy Gagnon

Alexandre Drapeau

Mario L'heureux

Nicholas Cole

Provided herein is a solution for measuring the optical power loss of duplex optical-fiber devices under test, and particularly those terminated with a duplex connector interface, which allows for a one-cord testing method whichever the format of the duplex connector interface of the optical-fiber device under test, without disconnecting the optical fibers of the device under test from their duplex native connector interface. Provided is an optical-fiber expansion device used to interconnect and adapt a power meter instrument to a variety of duplex connectors. The optical-fiber expansion device comprises a pair of optical fibers having a core diameter and a numerical aperture greater than the optical fiber in the DUT connector interface, to make it compatible with the one-cord testing method. Interchangeable optical-fiber expansion devices can be used to match the power meter interface on one side, to various duplex connector interfaces under test on the other side.

Duplex optical power loss measurement using an adaptor device

There is provided a technique to reduce the Rayleigh coherence noise in OTDR measurements using spectral averaging of OTDR traces while at least partly cancelling chromatic dispersion pulse broadening on the averaged OTDR trace by applying a chromatic dispersion correction prior to averaging the OTDR traces. By correcting for chromatic dispersion pulse broadening, it allows to reduce the Rayleigh coherence noise without impacting the OTDR spatial resolution.

Spectral averaging of OTDR traces

There are provided herein test instruments, devices and methods for measuring the optical power loss of optical-fiber devices under test, and particularly those terminated with multifiber connectors, which allows for a one-cord or one-cord equivalent reference method whichever the pinning of the actual optical-fiber device under test. There is proposed to add an optical-fiber expansion device to convert the pinning of the input interface of the power meter instrument from pinned to unpinned or vice-versa, while not adding extra measurement uncertainty. This is accomplished using a patch cord which core diameter is between that of the device under test and that of the input interface of the power meter instrument.

Optical-fiber device for one-cord reference optical power loss measurement

There is provided optical power loss measurement method and system for that aims to provide a more productive way to perform optical power loss measurements involving test units typically at different locations. Visual fiber finder light can be used to assist the user at the other end of the optical fiber link under test in identifying where to connect the power meter unit. A visual fiber finder light and test light are combined on a same output port of a light source unit at one end of the optical fiber link under test wherein visual fiber finder light is interleaved with test light in a cyclic sequence so that both are not active at the same time. The optical power meter unit determines a time slot when to measure test light in accordance with the given cyclic sequence.

Visual fiber finder for sequencing optical fiber testing

There is provided a system and a method for assisting a technician in fiber optic cable splices and comprising a pair of test units including an OTDR, an optical switch, a tone generator and a tone detector to automate the splicing process and testing. The test units may be in communication with a wireless portable device used by the splicing technician and controlled therefrom. In one embodiment, the test units are driven by a test orchestrator application (e.g., server-based) to switch fibers, perform continuity tests and/or splice quality tests, triggered by the technician's portable device.

System and method for assisting in fiber optic splices

There are provided methods and systems for testing the continuity of optical fiber links under test and/or a fiber arrangement, polarity or mapping of optical fiber connections within optical devices under test using the backscattering pattern as a signature. The device under test may comprises a single fiber, a duplex link, a multifiber cable or another multi-port device such as a backplane device.

Testing optical fiber link continuity using OTDR backscattering patterns

There are provided methods and systems that enable the use of the backscattering pattern produced by an optical fiber in an OTDR trace as a signature (also referred to herein as the 'RBS fingerprint') to recognize an optical fiber. It was found that it may be difficult to obtain repeatable signatures as those are sensitive to the wavelength of the OTDR laser source and the temperature of the fiber. OTDR methods and systems that are adapted to compare the backscattering pattern in a more repeatable manner are therefore provided. Once the repeatability issue is overcome, such signature can be used for identification purposes and enable new applications.

Optical fiber recognition using backscattering pattern

Display screen or portion thereof with graphical user interface

There are provided techniques for characterizing and testing a cable routing connection configuration connection arrangement comprising a plurality of optical fiber links connected between at least a first connection device at a first end and a second multi-fiber connection device at a second end. Test light is injected into one or more of the optical fiber links via corresponding optical fiber ports of the first connection device. At least one image of the second multi-fiber connection device is captured. Test light exiting the optical fiber link(s) through optical fiber port(s) of the second multi-fiber connection device is imaged as light spot(s) in the captured image. Positions on the second multi-fiber connection device that corresponds to the optical fiber port(s) are determined based on a pattern of the light spot(s) in the captured image. In some implementations, the provided techniques allow detection or verification of cable routing connection configurations at multi-fiber distribution panels.

Method and system for multi-link connection testing

There is provided a test device and a test method that combine both tunable OTDR and WDM power meter functionalities into the same integrated optoelectronic test hardware, such that the tunable OTDR and the WDM power meter functions share optoelectronic components, thereby reducing the hardware cost and the overall form factor and weight of the test device. With the proposed configuration, both tunable OTDR and WDM power meter functionalities may be provided via a single test port to be connected to the optical fiber link under test. By connecting the fiber to a single test port, the number of manipulations to be performed by technicians is reduced and two tests can be performed in a single connection operation out of the same test port.

Test device with both OTDR and WDM power meter modes

There is provided a method and a system for identifying or verifying the fiber arrangement and/or the cable type of multi-fiber array cables (such as MPO cables) which employs an OTDR acquisition device at the near end of the MPO cable, a loopback device at the far end and an array of signatures detectable by the OTDR, either at the far or the near end. The loopback device allows performing bidirectional OTDR measurements with a single OTDR acquisition device (without moving it from one end to the other) and the signature array provides fiber arrangement/cable type identification or verification.

Testing fiber arrangement in multi-fiber cables

There is provided a system and a test instrument for identifying or verifying the fiber arrangement and/or the cable type of multi-fiber array cables (such as MPO cables) which employs a light source and a polarity detector at the near end of the multi-fiber array cable under test, and a loopback device at the far end. The polarity detector comprises light presence detectors used to detect which one of the optical fibers of the multi-fiber array cable returns light looped back at the far end and thereby determine the fiber arrangement and/or the cable type of the multi-fiber array cable.

There is provided a bi-directional optical reflectometric method for characterizing an optical fiber link. The method comprises: performing at least one forward-direction light acquisition from one end of the optical fiber link and performing at least one backward-direction light acquisition from the opposite end, wherein each light acquisition is performed by propagating at least one test light signal corresponding to given spatial resolution and detecting corresponding return light so as to obtain a reflectometric trace representing backscattered and reflected light as a function of a distance on the optical fiber link, and wherein said forward-direction light acquisition and said backward-direction light acquisition are performed with mutually different spatial resolutions; and deriving a value of at least one parameter characterizing an event at a location along said optical fiber link at least using the forward-direction light acquisition and the backward-direction light acquisition performed with mutually different spatial resolutions.

Bi-directional multi-pulsewidth optical time-domain reflectometer

There is provided an optical reflectometric method and system for characterizing an optical fiber link, wherein events in the fiber optic link under test are identified and values of parameters characterizing the events (e.g. location, insertion loss and reflectance) are extracted from an analysis of one or more reflectometric measurements performed on the optical fiber link. A loss profile and/or a reflectance profile are then constructed. The loss and reflectance profiles are typically displayed on screen or otherwise graphically represented for an operator to be able to appreciate the measurement results at a single glance.

Optical reflectometer with loss and/or reflectance profile view

There is provided a bi-directional optical reflectometric method for characterizing an optical fiber link. The method comprises: performing a plurality of forward-direction light acquisitions from one end of the optical fiber link and performing a plurality of backward-direction light acquisitions from the opposite end, wherein each light acquisition is performed by propagating at least one test light signal corresponding to given spatial resolution and detecting corresponding return light so as to obtain a reflectometric trace representing backscattered and reflected light as a function of a distance on the optical fiber link, and wherein said plurality of forward-direction light acquisitions and said plurality of backward-direction light acquisitions are each performed with mutually different spatial resolutions; and deriving a value of at least one parameter characterizing an event along said optical fiber link at least using a forward-direction light acquisition and a backward-direction light acquisition performed with mutually different spatial resolutions.

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CA

Michel Leclerc