EXFO FTB-5500B User Manual

FTB-5500B

PMD Analyzer for FTB-500

User Guide

Copyright © 2003–2009 EXFO Electro-Optical Engineering Inc. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form, be it electronically, mechanically, or by any other means such as photocopying, recording or otherwise, without the prior written permission of EXFO Electro-Optical Engineering Inc. (EXFO).

Information provided by EXFO is believed to be accurate and reliable. However, no responsibility is assumed by EXFO for its use nor for any infringements of patents or other rights of third parties that may result from its use. No license is granted by implication or otherwise under any patent rights of EXFO.

EXFO’s Commerce And Government Entities (CAGE) code under the North Atlantic Treaty Organization (NATO) is 0L8C3.

The information contained in this publication is subject to change without notice.

Trademarks

EXFO’s trademarks have been identified as such. However, the presence or absence of such identification does not affect the legal status of any trademark.

Units of Measurement

Units of measurement in this publication conform to SI standards and practices.

Patents

The Polarization Mode Dispersion Analyzer is the subject of International PCT application, publication number WO 2004/070341; EXFO’s Universal Interface is protected by US patent 6,612,750.

Version number 4.0.1

ii FTB-5500B

Contents

Certification Information ....................................................................................................... vi

1 Introducing the FTB-5500B Polarization Mode Dispersion Analyzer ......... 1

Main Features .........................................................................................................................1

Typical Applications ................................................................................................................2

Basic Polarization Mode Dispersion Theory .............................................................................3

Conventions ............................................................................................................................6

2 Safety Information ....................................................................................... 7

3 Getting Started with Your Polarization Mode Dispersion Analyzer .......... 9

Inserting and Removing Test Modules ....................................................................................9

Starting the Polarization Mode Dispersion Analyzer Application ..........................................13

Exiting the Application .........................................................................................................17

4 Setting Up the Polarization Mode Dispersion Analyzer ........................... 19

Defining the Automatic Fiber Name Format .........................................................................19

Customizing PMD Value and Coefficient Thresholds .............................................................20

Setting Acquisition Parameters .............................................................................................24

Preparing for Multiple Acquisitions on a Fiber ......................................................................28

Averaging Measurements .....................................................................................................31

5 Operating the Polarization Mode Dispersion Analyzer ............................ 33

Cleaning and Connecting Optical Fibers ...............................................................................33

Installing the EXFO Universal Interface (EUI) .........................................................................34

Setting Up Hardware for Measurements ...............................................................................36

Acquiring Traces ...................................................................................................................39

Performing a Null Measurement ...........................................................................................41

Viewing the Input Power Level .............................................................................................42

Polarization Mode Dispersion Analyzer iii

Contents

6 Managing Results .......................................................................................43

Customizing Graph View ......................................................................................................43

Viewing Acquisition Results and Information .......................................................................44

Removing Unwanted Results ................................................................................................49

Viewing Statistics ..................................................................................................................51

Linking Distinct Fibers to a Single Fiber ................................................................................54

Creating New Result Files with Selected Fibers .....................................................................56

Documenting Results ............................................................................................................58

Defining a Template for Test Information ..............................................................................62

Saving Results Files ...............................................................................................................63

Exporting Results and Graphs ...............................................................................................64

Customizing Reports .............................................................................................................67

Printing Data ........................................................................................................................69

Closing Result Files ...............................................................................................................72

7 Exporting PMD Files with the File Converter ............................................73

Starting and Exiting the File Converter .................................................................................74

Setting Export Parameters ....................................................................................................76

Exporting PMD Files ..............................................................................................................78

8 Maintenance ................................................................................................81

Cleaning Fixed Connectors ....................................................................................................82

Cleaning EUI Connectors ......................................................................................................84

Recalibrating the Unit ...........................................................................................................86

Recycling and Disposal (Applies to European Union Only) ....................................................87

9 Troubleshooting ..........................................................................................89

Solving Common Problems ...................................................................................................89

Viewing Online Documentation ............................................................................................92

Contacting the Technical Support Group ..............................................................................93

Transportation ......................................................................................................................94

10 Warranty ......................................................................................................95

General Information .............................................................................................................95

Liability .................................................................................................................................96

Exclusions .............................................................................................................................97

Certification ..........................................................................................................................97

Service and Repairs ...............................................................................................................98

EXFO Service Centers Worldwide ..........................................................................................99

A Technical Specifications ............................................................................101

iv FTB-5500B

Contents

B Using Third-Party Broadband Light Sources ........................................... 103

Compliance Criteria ............................................................................................................103

Uncertainty Formula ...........................................................................................................105

Index .............................................................................................................. 107

Polarization Mode Dispersion Analyzer v

Certification Information

F.C.C. Information

Electronic test equipment is exempt from Part 15 compliance (FCC) in the United States. However, compliance verification tests are systematically performed on most EXFO equipment.

 Information

Electronic test equipment is subject to the EMC Directive in the European Union. The EN61326 standard prescribes both emission and immunity requirements for laboratory, measurement, and control equipment. This unit has undergone extensive testing according to the European Union Directive and Standards.

vi FTB-5500B

Certification Information

DECLARATION OF CONFORMITY

Application of Council Directive(s): 2006/95/EC - The Low Voltage Directive

Manufacturer’s Name: EXFO Electro-Optical Engineering Inc. Manufacturer’s Address: 400 Godin Avenue Quebec, Quebec

(418) 683-0211 Equipment Type/Environment: Test & Measurement / Industrial Trade Name/Model No.: FTB-5500B

Standard(s) to which Conformity is Declared:

EN 61010-1:2001 Safety Requirements for Electrical Equipment for Measurement,

EN 61326-1:2006 Electrical Equipment for Measurement, Control and Laboratory

EN 60825-1:1994 +A2:2001 +A1:2002

EN 55022: 1998 +A2: 2003 Information technology equipment - Radio disturbance

I, the undersigned, hereby declare that the equipment specified above conforms to the above Directive and Standards.

Manufacturer

Signature:

Control, and Laboratory Use, Part 1: General Requirements.

Use - EMC Requirements – Part 1: General requirements

Safety of laser products – Part 1: Equipment classification, requirements, and user’s guide

characteristics - Limits and methods of measurement

2004/108/EC - The EMC Directive And their amendments

Canada, G1M 2K2

PMD Analyzer

Full Name: Stephen Bull, E. Eng

Position: Vice-President Research and

Address: 400 Godin Avenue, Quebec (Quebec),

Date: January 09, 2009

Development

Canada, G1M 2K2

Polarization Mode Dispersion Analyzer vii

1 Introducing the FTB-5500B

Polarization Mode Dispersion Analyzer

Main Features

Polarization mode dispersion (PMD) is the dispersion of light propagating along a fiber or through a device due to the birefringence property of the material. This dispersion causes a delay between two principal states of polarization

The FTB-5500B Polarization Mode Dispersion Analyzer takes full advantage of the IEC- and TIA-approved interferometric method to offer a fast and field-proof unit that can handle almost any situation. This unit, used with the FLS-5800 CD/PMD Analyzer Source, features the best dynamic range on the market to measure links longer than 200 km. The Polarization Mode Dispersion Analyzer covers the O+C+L bandwidth.

The FTB-5500B Polarization Mode Dispersion Analyzer offers a dynamic range higher than 50 dB for long-haul applications; multiple-measurement capability for long-term monitoring; and an estimated second-order PMD for DWDM system fiber certifications.

Polarization Mode Dispersion Analyzer 1

Introducing the FTB-5500B Polarization Mode Dispersion Analyzer

Typica l A p p l i cations

The FTB-5500B Polarization Mode Dispersion Analyzer is a complete PMD analyzer system. It measures PMD using the internationally recognized interferometric method. The Polarization Mode Dispersion Analyzer averages PMD over the complete source wavelength range without any filtering, leaving all the source power for PMD measurement. The full dynamic range remains available to test long fiber spans. It can withstand small vibrations thanks to its fast measurement time and does not require any special environmental setup to perform reliable measurements.

PMD

Handle

FTB-5500B

Port

Typical Applications

The Polarization Mode Dispersion Analyzer can also analyze a signal transmitted through erbium-doped fiber amplifiers (EDFAs) providing a total PMD value for the entire link.

2 FTB-5500B

Introducing the FTB-5500B Polarization Mode Dispersion Analyzer

Basic Polarization Mode Dispersion Theory

The dispersion phenomenon is described as a number of non-intensity-dependant physical occurrences resulting directly in signal loss (pulse spreading or time jitter in a digital system; distortion in an analog system). PMD is an important type of signal dispersion. As unrepeated link distances are increased and transmission rates pushed upwards, PMD can significantly reduce system performance.

To better understand the impact of PMD, consider the example of a pulse passing through a wave plate. Upon entering the wave plate, the pulse is decomposed into polarization components aligned with each of the two birefringent axes of the plate (known as the fast and slow axes). The components propagating independently through the wave plate at different group velocities will recombine at the end of the wave plate as a superposition of two pulses split in time.

The delay between those pulses is designated as the differential group delay (DGD) and is written as δτ. For a Gaussian, unchirped input pulse of rms width σ0, the rms width at the output is given by

= σ

+ r0 (1 − r0)•δτ

where r0 is the fraction of the input-pulse energy launched into one of the birefringence axes.

Worst-case spreading occurs when the signal is perfectly split in two (r0 = 1/2), while no spreading occurs if the input state of polarization (SOP) of the launched signal is aligned with one of the birefringence axes.

To generalize this example, consider a long, weakly birefringent telecommunications fiber as a concatenation of many, randomly orientated birefringent wave plates. Each interface between two wave plates redistributes the optical energy along both axes of the subsequent wave plate. This transfer of energy is called mode coupling.

Polarization Mode Dispersion Analyzer 3

Introducing the FTB-5500B Polarization Mode Dispersion Analyzer

Basic Polarization Mode Dispersion Theory

In a long fiber, numerous mode-coupling events occur along the fiber length, so that light emerging from the output end is the superposition of a number of pulses with different delays. Nonetheless, it turns out that for any given optical frequency, principal states of polarization (PSPs) such that a light pulse with the same input SOP as the input PSP, undergoes no spreading. For a single wave plate, the PSPs are the two birefringent axes, whereas for a concatenation of wave plates, neither the input nor the output PSPs correspond to the alignment of the birefringent axes anywhere.

Contrary to the case of a wave plate, the DGD and PSPs of a long fiber are dependent on wavelength and fluctuate in time as a result of environmental variations such as temperature, external mechanical constraints, etc. Their behavior is random, both as a function of wavelength at a given time and as a function of time at a given wavelength. Fortunately, this behavior can be characterized statistically. It can be demonstrated that the probability density function of δτ is Maxwellian and, by definition, PMD is its rms value, that is:

ω, one can always find two orthogonal input

PMD =

Note: PMD is sometimes defined as the mean value of the DGD, which for a

Maxwellian distribution yields a value 17% lower than the rms definition.

If the average is calculated over averaging window is sufficiently large (

4 FTB-5500B

√<DGD2>

ω, PMD is stable in time, provided that the

Δωδτ >> 1).

Introducing the FTB-5500B Polarization Mode Dispersion Analyzer

Basic Polarization Mode Dispersion Theory

It is essential to keep in mind that DGD fluctuates in time and can be either smaller or larger than its rms value or PMD. This results in a statistical probability that a pulse (information bit) is broadened, and leads to the eventual impaired ability of the receiver to efficiently decode the information. This adverse PMD effect makes it a critical phenomenon in limiting transmission of high-bit-rate information.

In the case of PMD in a long fiber, there is a specific state called input PSP. In this state, when the input SOP of the signal is aligned with one of its axes, it will propagate through the fiber without any spreading or distortion of the signal. This phenomenon is defined as this specific input SOP such that the output SOP is independent of optical frequency. Again, the worst case occurs when the signal is equally split between both input PSPs.

For long telecom fibers with random coupling of energy between modes (that is L >> h where h is the coupling length), PMD grows as the square root of the distance, whereas PMD of strong HiBi fiber (negligible mode coupling) is directly proportional to the distance. Therefore, the PMD coefficient for negligible mode coupling is expressed as ps/km, while the PMD coefficient for random mode coupling is defined as ps/km

1/2

Polarization Mode Dispersion Analyzer 5

Introducing the FTB-5500B Polarization Mode Dispersion Analyzer

Conventions

Before using the product described in this manual, you should understand the following conventions:

WARNING

Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury. Do not proceed unless you understand and meet the required conditions.

CAUTION

Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury. Do not proceed unless you understand and meet the required conditions.

CAUTION

Indicates a potentially hazardous situation which, if not avoided, may result in component damage. Do not proceed unless you understand and meet the required conditions.

IMPORTANT

Refers to information about this product you should not overlook.

6 FTB-5500B

2 Safety Information

WARNING

Do not install or terminate fibers while a light source is active. Never look directly into a live fiber and ensure that your eyes are protected at all times.

WARNING

Use of controls, adjustments and procedures for operation and maintenance other than those specified herein may result in hazardous radiation exposure or impair the protection provided by this unit.

Your instrument is a Class 1 laser product in compliance with standards IEC60825-1: 2001, 2007 and 21CFR1040.10. Laser radiation may be encountered at the output port.

The following label indicates that a product contains a Class 1 source:

CLASS 1

LASER PRODUCT

Note: Label shown for information purposes only. It is not affixed to your product.

Polarization Mode Dispersion Analyzer 7

3 Getting Started with Your

Polarization Mode Dispersion Analyzer

Inserting and Removing Test Modules

CAUTION

Never insert or remove a module while the FTB-500 is turned on. This will result in immediate and irreparable damage to both the module and unit.

WARNING

When the laser safety LED ( ) is flashing on the FTB-500, at least one of your modules is emitting an optical signal. Please check all modules, as it might not be the one you are currently using.

To insert a module into the FTB-500:

1. Exit ToolBox and turn off your unit.

2. Position the FTB-500 so that its right panel is facing you.

Polarization Mode Dispersion Analyzer 9

Getting Started with Your Polarization Mode Dispersion Analyzer

Inserting and Removing Test Modules

3. Take the module and place it so that the connector pins are at the back, as explained and shown below.

Identification sticker must be facing up and connector pins at the right of the retaining screw hole.

FTB-500 right panel

4. Insert the protruding edges of the module into the grooves of the

5. Push the module all the way to the back of the slot, until the retaining

6. Place the FTB-500 so that its left panel is facing you.

Retaining screw

hole at the

back

Identification sticker

facing up

receptacle’s module slot.

screw makes contact with the receptacle casing.

Connector pins at the back

Protruding

edges on top

10 FTB-5500B

Getting Started with Your Polarization Mode Dispersion Analyzer

Inserting and Removing Test Modules

7. While applying slight pressure to the module, turn the retaining screw clockwise until it is tightened.

This will secure the module into its “seated” position.

Turn retaining screw knob

clockwise

FTB-500 left panel

When you turn on the unit, the startup sequence will automatically detect the module.

Polarization Mode Dispersion Analyzer 11

Getting Started with Your Polarization Mode Dispersion Analyzer

Inserting and Removing Test Modules

To remove a module from the FTB-500:

1. Exit ToolBox and turn off your unit.

2. Position the FTB-500 so that the left panel is facing you.

3. Turn the retaining screw counterclockwise until it stops.

The module will be slowly released from the slot.

Turn retaining screw knob(s)

counterclockwise

FTB-500 left panel

4. Place the FTB-500 so that the right panel is facing you.

12 FTB-5500B

Getting Started with Your Polarization Mode Dispersion Analyzer

Inserting and Removing Test Modules

5. Hold the module by its sides or by the handle (NOT by the connector) and pull it out.

Polarization Mode Dispersion Analyzer 13

Getting Started with Your Polarization Mode Dispersion Analyzer

Starting the Polarization Mode Dispersion Analyzer Application

Your FTB-5500B Polarization Mode Dispersion Analyzer module can be configured and controlled from its dedicated ToolBox application.

Note: For details about ToolBox, refer to the FTB-500 user guide.

To start the application:

1. From the main window, select the module to use.

It will turn blue to indicate that it is highlighted.

2. Click the corresponding button in the Module Applications box.

14 FTB-5500B

Getting Started with Your Polarization Mode Dispersion Analyzer

Starting the Polarization Mode Dispersion Analyzer Application

The main window (shown below) contains all the commands required to control the Polarization Mode Dispersion Analyzer:

Data

display

Zoom controls

Power level indicator

Measurement selector

Export controls

Threshold indicator specifies if measurement exceeded value or not

Title bar

Start/Stop button

Function buttons

Status bar

Polarization Mode Dispersion Analyzer 15

Getting Started with Your Polarization Mode Dispersion Analyzer

Starting the Polarization Mode Dispersion Analyzer Application

Data Display

The data display section shows both a graph and a table of results. The graph presents a signal intensity trace as a function of delay. The table presents information and results related to the measurement specified in the measurement selector.

Signal

intensity in

percentage

PMD time

delay in

picoseconds

Measurement

selector

16 FTB-5500B

Getting Started with Your Polarization Mode Dispersion Analyzer

Exiting the Application

Status Bar

The status bar, located at the bottom of the main window, identifies the operational status of the FTB-5500B Polarization Mode Dispersion Analyzer.

Control mode

Local: Module controlled locally only.

Remote: Module controlled remotely, but local

commands can also be used (some products only).

Lockout: Module controlled remotely only.

Current date and time

Battery indicator

For more information about automating or remotely controlling the FTB-5500B Polarization Mode Dispersion Analyzer, refer to your platform user guide.

Exiting the Application

Closing any application that is not currently being used helps freeing system memory.

To close the application from the main window:

Click in the top right corner of the main window.

Click the Exit button located at the bottom of the function bar.

Polarization Mode Dispersion Analyzer 17

4 Setting Up the Polarization

Mode Dispersion Analyzer

The many features of the Polarization Mode Dispersion Analyzer are controlled by the Windows-compatible ToolBox software. Please refer to the FTB-500 user guide for information regarding the FTB-500.

Defining the Automatic Fiber Name Format

Each time you make a new acquisition, the fiber name changes automatically according to a pattern you will have previously defined. This name corresponds to the concatenation of a static part (prefix) and a variable part that will be incremented.

Note: The fiber name can be modified later with the measurement information

utility. For more information, see Documenting Results on page 58.

To define the fiber name format:

1. From the main window, click the Parameters tab.

2. From the Fiber Auto Naming panel, set the various parameters

according to your needs.

Fiber identification number. Will change

according to the specified increment value.

Number of digits composing the fiber

identification number.

Value that will be added the fiber identification

Polarization Mode Dispersion Analyzer 19

Displayed just before the number in the fiber name.

number to build the next fiber name.

Setting Up the Polarization Mode Dispersion Analyzer

Customizing PMD Value and Coefficient Thresholds

The Polarization Mode Dispersion Analyzer allows you to specify PMD and coefficient values that will be used to determine whether the results are as expected or if they exceed the specified limits.

Note: You cannot modify or delete the predefined thresholds provided with your

Polarization Mode Dispersion Analyzer.

To add a new threshold:

1. From the button bar, click Setup.

20 FTB-5500B

2. From the PMD Value panel, click Add.

Current

threshold values

(preceded by

bullets)

Setting Up the Polarization Mode Dispersion Analyzer

Customizing PMD Value and Coefficient Thresholds

From the PMD Coefficient panel, click Add.

3. From the PMD Value list, select the threshold that has just been added.

From the PMD Coefficient list, select the threshold that has just been added.

4. Fill in the Name and Value boxes according to your needs.

Note: If you want the Polarization Mode Dispersion Analyzer to use this new

value next time you will make an acquisition, you will have to set it from the main window Parameters tab (see Setting Acquisition Parameters on page 24).

Polarization Mode Dispersion Analyzer 21

Setting Up the Polarization Mode Dispersion Analyzer

Customizing PMD Value and Coefficient Thresholds

To m o d i fy a n e xisting threshold:

1. From the button bar, click Setup.

2. From the PMD Value list, select the threshold to be modified.

From the PMD Coefficient list, select the threshold to be modified.

3. Modify the contents of the Name and Valu e boxes according to your needs.

Note: If you want the Polarization Mode Dispersion Analyzer to use this new

value next time you will make an acquisition, you will have to set it from the main window Parameters tab (see Setting Acquisition Parameters on page 24).

22 FTB-5500B

Setting Up the Polarization Mode Dispersion Analyzer

Customizing PMD Value and Coefficient Thresholds

To delete an existing threshold:

1. From the button bar, click Setup.

2. From the PMD Value list, select the threshold to be deleted.

From the PMD Coefficient list, select the threshold to be deleted.

3. Click Delete.

To return to the main window:

From the button bar, click Exit Setup.

Polarization Mode Dispersion Analyzer 23

Setting Up the Polarization Mode Dispersion Analyzer

Setting Acquisition Parameters

Your FTB-5500B Polarization Mode Dispersion Analyzer allows you to perform both single and multiple acquisitions on fibers. Regardless of the type of acquisition you choose, you must define the parameters that will be taken into account during the measurements. Parameters are kept in memory even after turning off the FTB-500.

These parameters include:

Parameter Details

Fiber length Parameter compulsory since it will be used for PMD coefficient

calculations. The entered value must be equal to or greater than 0.001 km (1 m).

Fiber type Must be set to one of the following types:

³ Tel ec om; also known as strong coupling. If you are working

directly in the field, you will probably use this fiber type.

³ Polarization-Maintaining; also known as weak coupling.

Note: Traces taken with a particular fiber type cannot

be reanalyzed with a different fiber type afterwards.

Wavelength Must be set to one of the following values:

³ C and L Bands covers the 1460 nm to 1675 nm range.

³ O, C, L Bands covers the 1260 nm to 1675 nm range.

Note: Selecting the O, C, L Bands option will make your

Polarization Mode Dispersion Analyzer slower in acquiring PMD data.

PMD value and coefficient thresholds

24 FTB-5500B

Will act as a comparison value to determine whether results are within a specific limit or not.

Setting Up the Polarization Mode Dispersion Analyzer

Parameter Details

Results storage Offers the following possibilities:

³ Keep Files in Memory allows you to temporarily store the

results in memory for data processing purposes (for example, statistics). However, the more files in memory, the slower the application will be. You may prefer to save results automatically and to process them later.

³ Automatic Save After Measurement: When you select this

option, the application saves every acquisition automatically. It is particularly useful when taking multiple measurements to avoid saturating memory. It is also possible to save traces manually (see Saving Results Files on page 63).

³ You may want to define your own prefix, which will be used

as the static part of the automatic file name when a new file is generated.

The file will automatically be named in the following format:

Setting Acquisition Parameters

Prefix

FILE_2002_12_10_10_25_14.pmdB

Date (YYYY_MM_DD)

Time (HH_MM_SS)

Result file extension

The default prefix is FILE.

Polarization Mode Dispersion Analyzer 25

Setting Up the Polarization Mode Dispersion Analyzer

Setting Acquisition Parameters

To set the acquisition parameters:

1. From the main window, click the Parameters tab.

2. From the Fiber Parameters panel, set the fiber length, the fiber type

and the wavelength.

IMPORTANT

Ensure that the selected wavelength (bandwidth) is compatible with the wavelength that will be used for your light source.

26 FTB-5500B

Setting Up the Polarization Mode Dispersion Analyzer

Setting Acquisition Parameters

3. From the Measurement Parameters panel, select the PMD Threshold and/or Coefficient Threshold list to set the PMD and/or coefficient values.

Note: If you want to modify the contents of PMD Threshold or Coefficient

Threshold boxes, see Customizing PMD Value and Coefficient Thresholds

on page 20.

4. Set the data storage parameters.

The parameters that you have just set will be used when you make a new acquisition.

Polarization Mode Dispersion Analyzer 27

Setting Up the Polarization Mode Dispersion Analyzer

Preparing for Multiple Acquisitions on a Fiber

The multiple-measurement mode allows you to make multiple acquisitions on the same fiber by defining the number of measurements and the delay between them. The left part of the status bar indicates the time left until the next measurement.

Results obtained for a specific fiber can be stored in the same file or in distinct files. It is also possible to append new results to an existing file.

One

acquisition

per file

All acquisitions

in the same file

Before being able to use this mode, you must define the general acquisition parameters as well as the parameters that will be specific to multiple acquisitions only.

IMPORTANT

Do not change the test fiber between two acquisitions of a multiple measurement mode test since parameters set for a specific fiber may not apply to all fibers.

28 FTB-5500B

Setting Up the Polarization Mode Dispersion Analyzer

Preparing for Multiple Acquisitions on a Fiber

To prepare for multiple acquisitions on a fiber:

1. From the main window, click the Parameters tab.

2. Set the general acquisition parameters as explained in Setting

Acquisition Parameters on page 24.

3. From the Measurement Parameters panel, select Use Multiple-Measurements Mode.

4. From the Measurement Parameters panel, click Setup to set the parameters.

Polarization Mode Dispersion Analyzer 29

Setting Up the Polarization Mode Dispersion Analyzer

Preparing for Multiple Acquisitions on a Fiber

³ In the Measurement Count box, specify the number of

measurements the Polarization Mode Dispersion Analyzer will take on the same fiber.

³ In the Measurement Interval boxes (h, m, s), specify the delay

between each measurement.

³ If you want the application to prompt you when an error occurs,

from the displayed dialog box, select the Show Error Message After Measurement check box. However, be aware that, with this

option, the application interrupts the current test until someone acknowledges the message.

³ If you want all results pertaining to a specific fiber to be saved to

the same file, select the Save in Same File check box.

Do the same if you want the new results to be appended to an existing file and ensure that the desired file is open before starting the test. For more information on opening result files, see Viewing Acquisition Results and Information on page 44.

5. When you are done, click OK to confirm the new settings or Cancel to discard changes.

The parameters that you have just set will be used when you make a new acquisition.

30 FTB-5500B

Setting Up the Polarization Mode Dispersion Analyzer

Averaging Measurements

When you need extreme precision, you can add one polarization scrambler at the source output port and one at the receiver input port and use the averaging-measurements mode.

This testing mode will average the interferometric envelops at several states of polarization, which allows very precise measurements. If you intend to use this mode, you must provide a number of measurements (scans) corresponding to the number of polarization states to test.

To average measurements:

1. From the main window, click the Parameters tab, select the Use

Averaging-Measurements Mode check box.

2. In the Measurement Count box, enter the number of measurements that will be performed during the averaging process.

Polarization Mode Dispersion Analyzer 31

5 Operating the Polarization

Mode Dispersion Analyzer

Cleaning and Connecting Optical Fibers

IMPORTANT

To ensure maximum power and to avoid erroneous readings:

³ Always inspect fiber ends and make sure that they are clean as

explained below before inserting them into the port. EXFO is not responsible for damage or errors caused by bad fiber cleaning or handling.

³ Ensure that your patchcord has appropriate connectors. Joining

mismatched connectors will damage the ferrules.

To connect the fiber-optic cable to the port:

1. Inspect the fiber using a fiber inspection microscope. If the fiber is

clean, proceed to connecting it to the port. If the fiber is dirty, clean it as explained below.

2. Clean the fiber ends as follows:

2a. Gently wipe the fiber end with a lint-free swab dipped in isopropyl

alcohol.

2b. Use compressed air to dry completely.

2c. Visually inspect the fiber end to ensure its cleanliness.

Polarization Mode Dispersion Analyzer 33

Operating the Polarization Mode Dispersion Analyzer

Cleaning and Connecting Optical Fibers

3. Carefully align the connector and port to prevent the fiber end from touching the outside of the port or rubbing against other surfaces.

If your connector features a key, ensure that it is fully fitted into the port’s corresponding notch.

4. Push the connector in so that the fiber-optic cable is firmly in place, thus ensuring adequate contact.

If your connector features a screwsleeve, tighten the connector enough to firmly maintain the fiber in place. Do not overtighten, as this will damage the fiber and the port.

Note: If your fiber-optic cable is not properly aligned and/or connected, you will

notice heavy loss and reflection.

34 FTB-5500B

Operating the Polarization Mode Dispersion Analyzer

Installing the EXFO Universal Interface (EUI)

The EUI fixed baseplate is available for connectors with angled (APC) or non-angled (UPC) polishing. A green border around the baseplate indicates that it is for APC-type connectors.

Green border

indicates APC

option

Bare metal

(or blue border)

indicates UPC

option

To install an EUI connector adapter onto the EUI baseplate:

1. Hold the EUI connector adapter so the dust cap opens downwards.

2 3 4

2. Close the dust cap in order to hold the connector adapter more firmly.

3. Insert the connector adapter into the baseplate.

4. While pushing firmly, turn the connector adapter clockwise on the

baseplate to lock it in place.

Polarization Mode Dispersion Analyzer 35

Operating the Polarization Mode Dispersion Analyzer

Setting Up Hardware for Measurements

To measure PMD with the FTB-5500B Polarization Mode Dispersion Analyzer, EXFO recommends that you use the FLS-110P Light Source or the FLS-5800 CD/PMD Analyzer Source, which will provide you a larger dynamic range. If you intend to use a third-party light source, see Using Third-Party Broadband Light Sources on page 103.

Before making acquisitions, you must prepare your hardware properly.

To set up hardware for measurements with the FLS-5800 CD/PMD Analyzer Source:

1. Clean and verify the quality of the connectors being used.

2. Connect the device under test (DUT) as shown below.

CD/PMD ANALYZER SOURCE

FLS-5800

ENTER

Setup

Out

On/Off Band C/L

Active

PMD

DUT

FTB-5500B

3. Turn on the FLS-5800 CD/PMD Analyzer.

4. Select the C bandwidth.

5. Tu rn t he so u rce o n.

Note: For more information on the FLS-5800, please refer to the FLS-5800

CD/PMD Analyzer Source user guide included with your product.

36 FTB-5500B

Operating the Polarization Mode Dispersion Analyzer

Setting Up Hardware for Measurements

To set up hardware for measurements using the FLS-110P Light Source:

1. Clean and verify the quality of the connectors being used.

2. Connect the device under test (DUT) as shown below.

PMD

DUT

FTB-5500B

3. Turn on the FLS-110P unit.

4. Press CW to ensure that it is emitting in CW mode.

Polarization Mode Dispersion Analyzer 37

Operating the Polarization Mode Dispersion Analyzer

Setting Up Hardware for Measurements

5. If applicable, select the C bandwidth.

6. If the FLS-110 Light Source supply indicator flashes, press auto off to

deactivate the Auto Off mode. If this mode remains enabled, the light source could stop emitting during the test.

7. Tu rn t he so u rce o n.

8. Press high to select the highest output power. The HIGH LED lights up.

Note: The low output power can be used but the accuracy of the PMD will be

affected.

Note: For more information on the FLS-110P, please refer to the FLS-110 Light

Source user guide included with your unit.

38 FTB-5500B

Operating the Polarization Mode Dispersion Analyzer

Acquiring Traces

The Polarization Mode Dispersion Analyzer allows you to acquire single or multiple traces on a specific fiber. The results are displayed after each acquisition, which means that, in the multiple measurement mode, if you enter five as the number of acquisitions to be performed, the graph and grid content will be updated five times with new results.

Many devices designed to measure PMD are based on the interferometric method. This method supposes that the obtained curves correspond to Gaussian interferograms. The patented design of the Polarization Mode Dispersion Analyzer proposes a new approach.

To help you making links between the two methods, the application provides you with a Gaussian compliance factor. This factor, multiplied by the obtained PMD value, will give you the value you would obtain with a Gaussian-based approach.

To start an acquisition:

1. Set acquisition parameters as described in Setting Acquisition

Parameters on page 24.

2. Verify that the fiber (DUT) is properly connected, that the setup is appropriate, and that the source is activated.

3. From the button bar, click Start to start a measurement sequence.

Polarization Mode Dispersion Analyzer 39

Operating the Polarization Mode Dispersion Analyzer

Acquiring Traces

When the measurement is complete, the new PMD results are displayed both in the graph and in the grid.

Threshold indicator specifies if measurement exceeded value or not

40 FTB-5500B

Operating the Polarization Mode Dispersion Analyzer

Performing a Null Measurement

This feature allows you to perform an offset nulling of your FTB-5500B Polarization Mode Dispersion Analyzer. During this operation, no light should reach the detector port of the Polarization Mode Dispersion Analyzer.

The very first time you insert an FTB-5500B Polarization Mode Dispersion Analyzer into the FTB-500, the application will prompt you for a nulling.

EXFO recommends that you perform a null measurement just before verifying the input power level to ensure the accuracy of the displayed level.

To perform a null measurement:

1. From the main window, click the Parameters tab. Click Nulling and

follow the on-screen instructions.

2. When nulling is complete, click Close.

Polarization Mode Dispersion Analyzer 41

Operating the Polarization Mode Dispersion Analyzer

Viewing the Input Power Level

The power level indicator is a visual aid to estimate the incoming signal intensity as detected at the input port. The indicator remains visible at all times at the bottom of the screen, except during acquisitions.

To ensure more accurate readings of the power level, EXFO recommends that you perform a nulling first (see Performing a Null Measurement on page 41). The input power level should be in the green area.

42 FTB-5500B

6 Managing Results

Your FTB-5500B Polarization Mode Dispersion Analyzer allows you to work with two types of results:

³ Newly acquired results

³ Results loaded from existing files

It also offers customizing, saving, export and printing features based on these results.

Customizing Graph View

With the provided tools, you can zoom in on specific areas of the graph (displayed in the main window Results tab) to have a better view. By default, the application zooms in on the most significant area of the graph. You can also choose to display the graph with a black or a white background. Using a white background can be particularly useful before exporting or printing the graph.

Polarization Mode Dispersion Analyzer 43

Managing Results

Viewing Acquisition Results and Information

To view specific portions of the graph:

³ Select the desired type of zoom that will be applied when you will

press on the FTB-500 screen (or click on the graph with your mouse).

³ Select the desired mode (pan, zoom type, etc.).

Move view area

(pan)

Zoom in on a

selected area

Automatic zoom in

Automatic zoom out

To toggle between the available graph backgrounds:

Click the button to select the desired background.

Horizontal zoom

Vertical zoom

Horizontal and vertical zoom

To return to the original graph view:

Click the button to revert to most significant graph area.

Viewing Acquisition Results and Information

The application allows you to view current results and information directly or reload data from existing files.

The application provides:

³ a window presenting details for the measurement that you specify

³ a window giving you an overview of all of the available measurements

44 FTB-5500B

Managing Results

Viewing Acquisition Results and Information

Reloading Existing Files

You can reload existing files without losing the current results and information.

To reload an existing file:

1. From the button bar, click Storage and click Open.

A standard Open dialog box is displayed, allowing you to select the desired file.

Note: You can speed up file selection by selecting several files at the same time.

2. When you are done, from the displayed dialog box, click Open to load

the files.

3. From the button bar, click Exit Storage.

Note: If you omit to select a result from the list, the main window Results tab will

remain empty until you select one (see Viewing Results on page 46).

Polarization Mode Dispersion Analyzer 45

Managing Results

Viewing Acquisition Results and Information

Viewing Results

The application presents a graph and a results grid containing details on the specified measurement. It also offers a general view of both current results and reloaded files. In the general view window, you can find a legend of the symbols used to identify the measurement status.

To view a specific result and the related information:

1. From the main window Results tab, use the arrow next to the

measurement selector to specify which measurement to display.

Measurement

selector

46 FTB-5500B

Managing Results

Viewing Acquisition Results and Information

2. From the provided dialog box, select the desired measurement. Click

Select to confirm your choice or Cancel to discard the changes.

The graph and the grid are automatically updated accordingly.

Since the application displays only one result at a time, if you want distinct fibers to be considered as sections of a single fiber, use the linking feature (see Linking Distinct Fibers to a Single Fiber on page 54).

Polarization Mode Dispersion Analyzer 47

Managing Results

Viewing Acquisition Results and Information

To display an overall view of the results:

From the button bar, click Storage. All the current results and open files are listed.

Measurement

status

Legend

button

Click Legend to display the list of the symbols used.

If you want to modify the information of a specific measurement, see Documenting Results on page 58.

48 FTB-5500B

Removing Unwanted Results

When a problem occurs, such as a fiber break, you may want to remove the corresponding erroneous measurement. This could be useful to avoid distorting results and statistics.

Note: You can only remove measurements (not fibers).

IMPORTANT

If you remove all measurements from a specific file (represented by a ), this file will be deleted automatically from the hard disk of your FTB-500.

Managing Results

Removing Unwanted Results

Polarization Mode Dispersion Analyzer 49

Managing Results

Removing Unwanted Results

To remove unwanted results:

1. From the button bar, click Storage.

2. From the provided list, select the measurement to be removed and

click Remove.

3. A confirmation message will be displayed. Click Yes to confirm.

4. Repeat steps 1 to 3 for each measurement you want to remove.

The removal will only be effective if you save the changes (see Saving Results Files on page 63). If you want to discard the changes, simply

answer “No” when the application will prompt you to save the file.

50 FTB-5500B

Managing Results

Viewing Statistics

The FTB-5500B Polarization Mode Dispersion Analyzer offers two types of statistics:

³ Single fiber: based on measurements from a specific fiber

³ Multiple fiber: based on measurements from one or many fibers

The provided values include mean, standard deviation, minimum and maximum results for PMD value, as well as coefficient.

Polarization Mode Dispersion Analyzer 51

Managing Results

Viewing Statistics

To view statistics for a single fiber:

1. From the button bar, click Storage. Ensure that the results you intend

to use are displayed on the list. When you are done, click Exit Storage.

2. From the main window, click the Tools tab. Click Single-Fiber Statistics. Statistics for the first fiber on the list appears in the grid.

Selected fiber

Measurements

associated with

selected fiber

Statistics values for the selected fiber

You can specify which measurements must be taken into account for statistics by selecting or clearing the corresponding boxes. The Select All button allows you to quickly select all the boxes. The Select Valid button selects all the measurements that do not exceed the specified thresholds.

52 FTB-5500B

To view statistics for multiple fibers:

1. From the button bar, click Storage. Ensure that the results you intend

2. Click the Tools tab. Select Multiple-Fiber Statistics. Statistics based on

Selected fibers

Measurements

associated with

highlighted

fiber

Managing Results

Viewing Statistics

to use are displayed on the list. When you are done, click Exit Storage.

all the fibers on the list appears in the grid.

Statistics values based on all selected fibers

You can specify which fibers must be taken into account by selecting or clearing the corresponding boxes from the selected fibers list. The Select All and Deselect All buttons allow you to quickly perform selections.

For each fiber, you can also specify which measurements must be included in statistics. You simply have to click on the desired fiber to display the related measurements and to select or clear the corresponding measurement boxes. The Select All button allows you to quickly select all the boxes. The Select Valid button selects all the measurements that do not exceed the specified thresholds.

Polarization Mode Dispersion Analyzer 53

Managing Results

Linking Distinct Fibers to a Single Fiber

The FTB-5500B Polarization Mode Dispersion Analyzer allows you to link distinct fibers so that you can view PMD value and coefficient exactly as if they were sections of a single fiber. This is useful in cases where a long fiber cannot be tested directly from one end to the other.

The application gives information about length, PMD value and coefficient as well as the number of sections in the new fiber. The PMD value for the entire link corresponds to the following equation:

Σ(PMD

To view results for the new fiber:

1. From the button bar, click Storage. Ensure that the results you intend

to use are displayed on the list. When you are done, click Exit Storage.

)

54 FTB-5500B

Selected fibers

Measurements

associated with

highlighted

fiber

Managing Results

Linking Distinct Fibers to a Single Fiber

2. From the main window, click the Tools tab. Select Make Link. Information based on all the fibers on the list appears in the grid.

Results and information based on all selected fibers

For each fiber, you can also specify which measurements must be included in the statistics. Simply select the desired fiber to display the related measurements and select or clear the corresponding measurement boxes. The Select All button allows you to quickly select all the boxes. The Select Valid button selects all the measurements that do not exceed the specified thresholds.

Polarization Mode Dispersion Analyzer 55

Managing Results

Creating New Result Files with Selected Fibers

It is possible to merge data taken from distinct files into a single file by selecting the desired fibers. Creating this new file does not affect the original files, unless you explicitly ask to overwrite one of the files.

To create a new result file:

1. From the button bar, click Storage. Ensure that the results you intend

to use are displayed on the list. When you are done, click Exit Storage.

2. From the main window, click the Too ls tab. Ensure that Multiple-Fiber Statistics or Make Link is selected.

File generator

button

Selected fibers

Measurements

associated with

highlighted

fiber

56 FTB-5500B

Managing Results

Creating New Result Files with Selected Fibers

For each fiber, you can also specify which measurements must be included in statistics. Simply select the desired fiber to display the related measurements and select or clear the corresponding measurement boxes.

The Select All button allows you to quickly select all the boxes.

The Select Valid button selects all the measurements that do not exceed the specified thresholds.

3. From the Tools tab, click Build File.

4. When prompted, name the file to your convenience and save it.

Polarization Mode Dispersion Analyzer 57

Managing Results

Documenting Results

For easier management, you may want to add comments and information about the tests that are performed. It is possible to include general and specific information.

General information concerns jobs, receiver and source. Specific information is related to files, fibers and measurements. This information could be included later in reports or in exported ASCII files.

To speed up general information entry, you can also define a template that will be used for all new tests (see Defining a Template for Test Information on page 62).

To add general information:

1. From the button bar, click Storage. Ensure that the results you intend

to use are displayed on the list. When you are done, select Exit Storage.

2. From the main window, click the Results tab.

58 FTB-5500B

Managing Results

Documenting Results

3. To specify which test must be documented, select any measurement related to this test using the measurement selector.

Measurement

selector

4. Click Notepad to access the documentation window.

Results

documentation

indicator

5. Fill in the boxes according to your needs. When you are done, click

Exit Notepad.

Polarization Mode Dispersion Analyzer 59

Managing Results

Documenting Results

To add specific information:

1. From the button bar, click Storage. Ensure that the results you intend

to use are displayed on the list. When you are done, click Exit Storage.

2. Select the item you wish to document with the measurement selector and click the Measurement Information button to access the documentation window.

Measurement

selector

60 FTB-5500B

Managing Results

Documenting Results

3. Fill in the boxes according to your needs.

Information associated with selected item

IMPORTANT

Except for comments, all the information that you set for a measurement will be automatically applied to other measurements associated with the same fiber.

The modifications will only be effective if you save them (see Saving Results Files on page 63). If you want to discard the changes, simply

answer “No” when the application will prompt you to save the file.

Polarization Mode Dispersion Analyzer 61

Managing Results

Defining a Template for Test Information

It is possible to define a template that will be used to fill the general information boxes of all new tests. This way, you can simply make a few changes instead of having to fill in each box manually.

To define a template for test information:

1. From the main window, click the Parameters tab.

2. Click Notepad to access the documentation window.

Te mp l a te

mode

indicator

3. Fill in the boxes to build your template to your needs. When you are done, click Exit Notepad.

The information you have just entered will be automatically transferred into the corresponding boxes of all the new tests you will perform.

62 FTB-5500B

Managing Results

Saving Results Files

Results files can be saved automatically after each measurement (see Setting Acquisition Parameters on page 24) or manually when the need arises (current file or all open files).

Note: Full customization of file names is only possible when saving files

manually, one file at a time.

Note: If former results have not been saved yet, the application prompts you to

save them before starting a new test.

To save files:

From the button bar, click Quick Save to save all open files at the same time (no file name will be requested).

From the button bar, click Storage, and click:

³ Save As to save only the current file (you will be prompted to provide a

file name).

³ Save All to save all open files at the same time (no file name will be

requested).

Polarization Mode Dispersion Analyzer 63

Managing Results

Exporting Results and Graphs

The FTB-5500B Polarization Mode Dispersion Analyzer offers you the possibility of quickly building your own reports by copying results and graphs to the clipboard. Afterwards, the content of the clipboard can be pasted onto a word-processor document of your choice. Graphs are exported exactly as you see them on the screen (zoom factor and display are kept) except for background.

If you prefer to work with raw data to build your own tables and graphs see Exporting PMD Files with the File Converter on page 73.

Since information is stored to clipboard, you cannot export both results and graph simultaneously. You must copy them one at a time.

IMPORTANT

64 FTB-5500B

To export results to clipboard:

1. From the main window Results tab, use the measurement selector to

Measurement

selector

Managing Results

Exporting Results and Graphs

specify which measurement must be displayed.

2. Click Copy Results.

3. Paste the content of the clipboard onto a word processor document,

for example.

Polarization Mode Dispersion Analyzer 65

Managing Results

Exporting Results and Graphs

To export graphs to clipboard:

1. From the main window Results tab, use the measurement selector to

specify which measurement must be displayed.

Measurement

selector

2. Adjust graph display to your needs. For more information, see

Customizing Graph View on page 43.

3. Click Copy Graph.

4. Paste the content of the clipboard onto a word processor document,

for example.

66 FTB-5500B

Managing Results

Customizing Reports

The FTB-5500B Polarization Mode Dispersion Analyzer provides many report types that are used for printing. For each type of report, you can specify which information must be included in your document.

To set up report parameters:

1. From the button bar, click Print.

Polarization Mode Dispersion Analyzer 67

Managing Results

Customizing Reports

2. From the Setup tab, customize the report to suit your needs.

³ You can customize the title by entering it in the Report Title box.

³ You can also add a logo by using the Browse button.

³ Select the boxes corresponding to the information you want to see

in your report and clear those you do not want to see.

3. When you are done, from the button bar, click Exit Print. The report parameters are automatically saved for future use.

68 FTB-5500B

Managing Results

Printing Data

The FTB-5500B Polarization Mode Dispersion Analyzer allows you to preview and to print reports containing the test results or statistics from Microsoft Internet Explorer. For information on how to modify report templates, see Customizing Reports on page 67.

To preview or print a report:

1. From the button bar, click Print.

Printing Data

Polarization Mode Dispersion Analyzer 69

Managing Results

Printing Data

2. From the Print tab, select the desired report type.

Note: If you do not customize the graph appearance, it will be presented with the

default settings (no zoom factor).

Note: Graphs only appear in reports if you select the Measurements Report

option.

Select which items must be included. The table below gives you more information on possible selections.

If you have selected... Specify...

Measurements Which measurements must be included in

the report by selecting the corresponding boxes.

You can also click Select All or Deselect All to quickly select or clear all boxes at the same time.

70 FTB-5500B

Managing Results

Printing Data

If you have selected... Specify...

Fibers Which fibers must be included in the report

by selecting the corresponding boxes.

You can also click Select All or Deselect All to quickly select or clear all boxes at the same time.

Statistics No fiber or measurement selection can be

made from the current window. You can select the fibers you want to include, but not the individual measurements.

Link No fiber or measurement selection can be

made from the current window. You can select the fibers you want to include, but not the individual measurements.

3. When you are done, click Print to open the preview. If you want to send the document to a printer, use the Print function of Microsoft Internet Explorer.

4. From the button bar, click Exit Print to return to the main window.

Polarization Mode Dispersion Analyzer 71

Managing Results

Closing Result Files

For easier result management, you may want to close the result files manually.

Note: You do not need to close files manually before exiting the Polarization

Mode Dispersion Analyzer application. You will be prompted if some result files have not been saved.

To c l os e f i le s :

1. From the button bar, click Storage, and click:

³ Close to close only the current file.

³ Close All to close all open files at the same time.

2. When you are done, from the button bar, click Exit Storage to return to the main window.

72 FTB-5500B

7 Exporting PMD Files with the

File Converter

The File Converter tool has been designed to export PMD files to specific formats:

³ From PMD-5500 files to PMD-5500B files (allows to load files created

with former PMD Analyzer)

³ From PMD-5500 files to ASCII files

³ From PMD-5500B files to ASCII files

You can also fully customize the contents of the generated files by exporting only the information you need.

Polarization Mode Dispersion Analyzer 73

Exporting PMD Files with the File Converter

Starting and Exiting the File Converter

To start the converter:

³ From ToolBox, click the Applications tab. Click PMD File

ImportExport.

³ From the FTB-5500B Polarization Mode Dispersion Analyzer

application, click the Storage button. Click Converter.

74 FTB-5500B

Files to be

exported

Information

about the

export

process

Exporting PMD Files with the File Converter

Starting and Exiting the File Converter

The File Converter main window is displayed.

Function tabs

To exit the converter:

³ Click (in the top right corner of the main window).

³ Click the Exit button located at the bottom of the function bar.

Polarization Mode Dispersion Analyzer 75

Exporting PMD Files with the File Converter

Setting Export Parameters

Before exporting data from one format to another, you must define:

³ Which information must be exported: You can export general test

information (fiber ID, thresholds, PMD value, etc.) as well as points from the acquired traces. This is particularly useful if you intend to build your own graphs using Microsoft Excel, for instance.

³ The conversion type (from PMD-5500 to PMD-5500B, from PMD-5500 to

ASCII or from PMD-5500B to ASCII).

³ Where to export files.

The parameters you set will remain unchanged until you choose to modify them. They will still be available after the computer has shut down.

To set export parameters:

1. Open the File Converter tool (see Starting and Exiting the File

Converter on page 74).

2. Select the desired conversion type.

76 FTB-5500B

Exporting PMD Files with the File Converter

Setting Export Parameters

3. If you selected a conversion to the ASCII format, from the Settings function tab, select all the boxes corresponding to the information you want to export.

Note: If you select Interferometric Envelope, all points acquired during the test

will be exported.

4. From the Export Folder panel, click the Browse button to specify in which folder the exported files will be stored.

Polarization Mode Dispersion Analyzer 77

Exporting PMD Files with the File Converter

Exporting PMD Files

Once the export parameters are set, you are now ready to start exporting PMD files. Files that cannot be exported (for example, corrupt files) will be skipped and their export status will change to “Fa ile d”.

IMPORTANT

To avoid errors during file export, ensure that all the files you intend to use are closed. A file that is selected in the Results tab of the Polarization Mode Dispersion Analyzer main window is considered open.

To e x p o rt P MD fi l es :

1. If necessary, close the files that you want to export (see Closing Result

Files on page 72).

2. If necessary, start the converter (see Starting and Exiting the File Converter on page 74).

3. If necessary, set up the export parameters (see Setting Export Parameters on page 76).

4. Click the Converter function tab of the File Converter.

78 FTB-5500B

Exporting PMD Files with the File Converter

Exporting PMD Files

5. Select the files.

5a. From the Files to Export panel, click Add.

A standard Open dialog box is displayed, allowing you to choose the desired file(s).

Note: You can speed up file selection by selecting several files at the same time.

5b. When you are done, click Open to transfer the files to the list.

You can remove a specific file by selecting it and clicking Remove. If you want to quickly empty the list, click Remove All.

6. From the Export Control panel, click the Export File(s) button to start the export process.

Successful export

Unsuccessful

export

Polarization Mode Dispersion Analyzer 79

8 Maintenance

To help ensure long, trouble-free operation:

³ Always inspect fiber-optic connectors before using them and clean

them if necessary.

³ Keep the unit free of dust.

³ Clean the unit casing and front panel with a cloth slightly dampened

with water.

³ Store unit at room temperature in a clean and dry area. Keep the unit

out of direct sunlight.

³ Avoid high humidity or significant temperature fluctuations.

³ Avoid unnecessary shocks and vibrations.

³ If any liquids are spilled on or into the unit, turn off the power

immediately and let the unit dry completely.

Use of controls, adjustments, and procedures for operation and maintenance other than those specified herein may result in hazardous radiation exposure.

WARNING

Polarization Mode Dispersion Analyzer 81

Maintenance

Cleaning Fixed Connectors

Regular cleaning of connectors will help maintain optimum performance. Do not try to disassemble the unit. Doing so would break the connector.

To clean fixed connectors:

1. Fold a lint-free wiping cloth in four to form a square.

2. Moisten the center of the lint-free wiping cloth with only one drop of

isopropyl alcohol.

Alcohol may leave traces if used abundantly. Avoid contact between the tip of the bottle and the wiping cloth, and do not use bottles that distribute too much alcohol at a time.

3. Gently wipe the connector threads three times with the folded and moistened section of the wiping cloth.

IMPORTANT

Isopropyl alcohol takes approximately ten seconds to evaporate. Since isopropyl alcohol is not absolutely pure, evaporation will leave microscopic residue. Make sure you dry the surfaces before evaporation occurs.

4. With a dry lint-free wiping cloth, gently wipe the same surfaces three times with a rotating movement.

5. Throw out the wiping cloths after one use.

82 FTB-5500B

Maintenance

Cleaning Fixed Connectors

6. Moisten a cleaning tip (2.5 mm tip) with only one drop of isopropyl alcohol.

IMPORTANT

Alcohol may leave traces if used abundantly. Avoid contact between the tip of the bottle and the cleaning tip, and do not use bottles that distribute too much alcohol at a time.

7. Slowly insert the cleaning tip into the connector until it reaches the ferrule inside (a slow clockwise rotating movement may help).

8. Gently turn the cleaning tip one full turn.

9. Continue to turn as you withdraw the cleaning tip.

10. Repeat steps 7 to 9, but this time with a dry cleaning tip (2.5 mm tip

provided by EXFO).

Note: Make sure you don’t touch the soft end of the cleaning tip and verify the

cleanliness of the cotton tip.

11. Throw out the cleaning tips after one use.

Polarization Mode Dispersion Analyzer 83

Maintenance

Cleaning EUI Connectors

Regular cleaning of EUI connectors will help maintain optimum performance. There is no need to disassemble the unit.

If any damage occurs to internal connectors, the module casing will have to be opened and a new calibration will be required.

To clean EUI connectors:

1. Remove the EUI from the instrument to expose the connector

baseplate and ferrule.

IMPORTANT

Turn

Push

2. Moisten a 2.5 mm cleaning tip with one drop of isopropyl alcohol (alcohol may leave traces if used abundantly).

3. Slowly insert the cleaning tip into the EUI adapter until it comes out on the other side (a slow clockwise rotating movement may help).

Pull

4. Gently turn the cleaning tip one full turn, then continue to turn as you withdraw it.

84 FTB-5500B

Cleaning EUI Connectors

5. Repeat steps 3 to 4 with a dry cleaning tip.

Note: Make sure you don’t touch the soft end of the cleaning tip.

6. Clean the ferrule in the connector port as follows:

6a. Deposit one drop of isopropyl alcohol on a lint-free wiping cloth.

IMPORTANT

Isopropyl alcohol may leave residues if used abundantly or left to evaporate (about 10 seconds).

Avoid contact between the tip of the bottle and the wiping cloth, and dry the surface quickly.

6b. Gently wipe the connector and ferrule.

6c. With a dry lint-free wiping cloth, gently wipe the same surfaces to

ensure that the connector and ferrule are perfectly dry.

6d. Verify connector surface with a portable fiber-optic

microscope(for example, EXFO’s FOMS) or fiber inspection probe(for example, EXFO’s FIP).

Maintenance

WARNING

Verifying the surface of the connector WHILE THE UNIT IS ACTIVE WILL result in permanent eye damage.

7. Put the EUI back onto the instrument (push and turn clockwise).

8. Throw out cleaning tips and wiping cloths after one use.

Polarization Mode Dispersion Analyzer 85

Maintenance

Recalibrating the Unit

Manufacturing and service center calibrations are based on the ISO/IEC 17025 Standard, which states that calibration documents must not contain a recommended calibration interval, unless this has been previously agreed upon with the customer.

Validity of specifications depends on operating conditions. For example, the calibration validity period can be longer or shorter depending on the intensity of use, environmental conditions and unit maintenance. You should determine the adequate calibration interval for your unit according to your accuracy requirements.

Under normal use, EXFO recommends calibrating your unit every year.

86 FTB-5500B

Maintenance

Recycling and Disposal (Applies to European Union Only)

Recycle or dispose of your product (including electric and electronic accessories) properly, in accordance with local regulations. Do not dispose of it in ordinary garbage receptacles.

This equipment was sold after August 13, 2005 (as identified by the black rectangle).

³ Unless otherwise noted in a separate agreement between EXFO and a

customer, distributor, or commercial partner, EXFO will cover costs related to the collection, treatment, recovery, and disposal of end-of-lifecycle waste generated by electronic equipment introduced after August 13, 2005 to an European Union member state with legislation regarding Directive 2002/96/EC.

³ Except for reasons of safety or environmental benefit, equipment

manufactured by EXFO, under its brand name, is generally designed to facilitate dismantling and reclamation.

For complete recycling/disposal procedures and contact information, visit the EXFO Web site at www.exfo.com/recycle.

Polarization Mode Dispersion Analyzer 87

9 Troubleshooting

Solving Common Problems

Before calling EXFO’s technical support, you may want to consider the following solutions to problems that could occur.

Message Possible cause Solution

Detected signal is out of user selected band.

Strong signal detected out of the selected band. Measurement may be erroneous.

Narrowband optical source detected. Measurement may be erroneous.

The frequency range of signal is out of measuring range. The acquisition operation was canceled.

No signal detected in the selected band. However, another signal has been detected outside the specified band. The application will try to take a measurement using the specified band.

Signal detected in the selected band. However, another strong signal has been detected elsewhere on the whole measurement band. Measurement accuracy can be affected.

The source being used has a very narrow bandwidth that prevents an accurate PMD measurement.

The frequency range of signal is out of measuring range (160 THz to 250 THz).

³ Ensure the source is on.

³ Ensure the source

wavelength matches the selected band for the Polarization M o d e Dispersion Analyzer.

Turn off the sources emitting at wavelengths that do not match the selected band for the Polarization Mode Dispersion Analyzer.

³ Use a LED or SLED

source.

³ Ensure no narrow

source is used for the selected band.

³ Use a source with a

wavelength matching the Polarization Mode Dispersion Analyzer bands.

³ Ensure that the source

power is sufficient.

Polarization Mode Dispersion Analyzer 89

Troubleshooting

Solving Common Problems

Message Possible cause Solution

Low signal-to-noise ratio. Power too-low in the

selected band.

Possible coupling mode selection error.

The selected coupling mode (Telecom or Polarization-Maintaining) does not match the coupling mode the Polarization Mode Dispersion Analyzer detects. Calculation will be performed using the selected coupling mode.

The signal is too low to compute a PMD value. The acquisition operation was canceled.

³ Power too-low in the

selected band.

³ The source being used

is modulated.

³ Use a source with a

higher output power.

³ Clean connectors

carefully.

³ Ensure connections are

made properly.

³ Ensure the source

wavelength matches the selected band for the Polarization M o d e Dispersion Analyzer.

Ensure that the selected coupling mode is appropriate.

³ Ensure the input power

is sufficient.

³ Use a LED or SLED

source.

The signal is saturated. Unable to compute PMD

Power is too high. Reduce the source output

power. value. The acquisition operation was canceled.

90 FTB-5500B

Troubleshooting

Solving Common Problems

Message Possible cause Solution

Specifications not guaranteed, retesting recommended.

The PMD value might no be within the unit’s specification:

³ You r PMD A naly z e r

measures low PMD values from a weak coupling device (for example, PMF) and analyzer input polarization state is not appropriate.

³ External parasitic signal

during measurement (for example, live fiber).

³ Move fiber or device

slightly to change polarization state and retest.

³ Remove parasitic signal

and retest.

Polarization Mode Dispersion Analyzer 91

Troubleshooting

Viewing Online Documentation

An online version of the FTB-5500B Polarization Mode Dispersion Analyzer user guide is available at all times from the application.

To access the online user guide:

Click Help in the function bar.

92 FTB-5500B

EXFO FTB-5500B User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Certification Information

Main Features

Typica l A p p l i cations

Basic Polarization Mode Dispersion Theory

Conventions

2 Safety Information

Inserting and Removing Test Modules

Starting the Polarization Mode Dispersion Analyzer Application

Exiting the Application

Defining the Automatic Fiber Name Format

Customizing PMD Value and Coefficient Thresholds

Setting Acquisition Parameters

Preparing for Multiple Acquisitions on a Fiber

Averaging Measurements

Cleaning and Connecting Optical Fibers

Installing the EXFO Universal Interface (EUI)

Setting Up Hardware for Measurements

Acquiring Traces

Performing a Null Measurement

Viewing the Input Power Level

6 Managing Results

Customizing Graph View

Viewing Acquisition Results and Information

Removing Unwanted Results

Viewing Statistics

Linking Distinct Fibers to a Single Fiber

Creating New Result Files with Selected Fibers

Documenting Results

Defining a Template for Test Information

Saving Results Files

Exporting Results and Graphs

Customizing Reports

Printing Data

Closing Result Files

Starting and Exiting the File Converter

Setting Export Parameters

Exporting PMD Files

8 Maintenance

Cleaning Fixed Connectors

Cleaning EUI Connectors

Recalibrating the Unit

Recycling and Disposal (Applies to European Union Only)

9 Troubleshooting

Solving Common Problems

Viewing Online Documentation