Viavi COSA-4055 User manual

MTS ⁄ T-BERD 5800
COSA-4055
User Manual

Please direct all enquiries to your local Viavi sales company.
The addresses can be found at:
www.viavisolutions.com/en-us/contact-sales-expert
The description of additional features of the device can be found
at:
www.viavisolutions.com/en-us/products/network-test-and-
certification
© Copyright 2016 Viavi Solutions Inc. All rights reserved.
Viavi and the Viavi logo are trademarks of Viavi Solutions Inc.
All other trademarks and registered trademarks are the
properties of their respective owners.
Viavi Solutions Deutschland GmbH
Arbachtalstraße 5, 72800 Eningen u. A.
Order no.: BN 3071/98.21
Edition: 2016.01
Previous Edition: 2015.03
Note: Changes may be made to specifications, descriptions and
delivery information.
Printed in Germany

MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 1
Contents
Introducing the COSA-4055 module . . . . . . . . . . . . . . . . 4
SFP slots. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Safety information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Proper usage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
General laser safety . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Specific laser safety . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Optical surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Battery operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Start the COSA application. . . . . . . . . . . . . . . . . . . . . . . . 9
Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Test Auto WDM mode . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Manual configuration. . . . . . . . . . . . . . . . . . . . . . . . . . 10
Acquisition parameters . . . . . . . . . . . . . . . . . . . . . . . . 11
Analysis parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Parameters of display and analysis of the results. . . . 14
Link Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
File Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Acquisition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Contents
2MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
Trace display functions. . . . . . . . . . . . . . . . . . . . . . . . . 20
Result display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Using the cursor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
The Zoom function . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
The Shift function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
The measurement function . . . . . . . . . . . . . . . . . . . . . 24
Multiple traces (Overlay) . . . . . . . . . . . . . . . . . . . . . . . 27
Table display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Table statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Channel sort. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Table notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Result colours . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Trace & Table display . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Drift measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Fast Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
File system report. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
File management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Storing OSA measurements . . . . . . . . . . . . . . . . . . . .39
Recalling OSA files. . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Recycling information . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Viavi Environmental Management Program. . . . . . . . . 40
RoHS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

1
MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 3
Chapter 1 Optical Spectrum
Measurement
This chapter describes the different stages in carrying out a spectrum
analysis of an optical CWDM signal.
The topics discussed in this chapter are as follows:
–“Introducing the COSA-4055 module” on page 4
–“Safety information” on page 5
–“Configuration” on page 9
–“Acquisition” on page 20
–“Result display” on page 21
–“Table display” on page 29
–“Trace & Table display” on page 34
–“Drift measurement” on page 34
–“File management” on page 39
–“Recycling information” on page 40
NOTE
This manual is an addition to the 5800 Base Unit user manual. For all
questions not covered in this manual – particularly concerning safety
– please refer to the Base Unit user manual.

Chapter 1 Optical Spectrum Measurement
Introducing the COSA-4055 module
4 MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
Introducing the COSA-4055 module
The COSA-4055 is Viavi’s new generation of CWDM analyzer modules.
It scans the full wavelength range between 1260 and 1625 nm for
commissioning, upgrade, and trouble shooting of CWDM networks. The
COSA-4055 offers the functionality and speed of an optical spectrum
analyzer in a handheld form at a fraction of the price of an OSA. The
measurement result is displayed in a graphical (trace) and numerical
(table) format providing detailed information of the power level and the
wavelength of CWDM channels.
Fig. 1 Two versions of the COSA-4055 modules
Basic Version
BN 2301/01
Advanced Version
BN 2301/02

Chapter 1 Optical Spectrum Measurement
Safety information
MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 5
The COSA-4055 comes in two versions. The basic version (BN 2301/01)
provides CWDM analyzer functionality only. The advanced version
(BN 2301/02) additionally offers 2 integrated SFP slots for mounting up
to 2 SFP transceiver modules (to be ordered separately). The transceiver
modules can be used as a CWDM stimulus to check CWDM networks
together with the CWDM analyzer.
SFP slots The COSA-4055 BN 2301/02 has two integrated SFP slots. Any
transceiver module connected to the SFP slot is automatically activated
and emits optical radiation at the output “TX”. The input “RX” of the
transceiver module has no function. The optical laser radiation is
indicated by LEDs assigned to the SFP slots. The SFP modules are hot
pluggable and can be changed during operation of the COSA-4055.
Safety information
Conventions This guide uses naming conventions and symbols, as described in the
following tables.
Symbol conventions
Version
2301/02 only
This symbol represents a general hazard.
This symbol represents a risk of electrical shock.
This symbol represents dangerous laser radiation.

Chapter 1 Optical Spectrum Measurement
Safety information
6 MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
Safety definitions
Proper usage This instrument is intended for measurements on optical fiber devices
and systems.
Please make sure the device is not operated outside the permitted
ambient conditions.
Observe the specified measurement range.
Always make sure that the device is in proper working order before
switching it on.
General
laser safety
WARNING
Indicates a potentially hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION
Indicates a potentially hazardous situation which, if not avoided, may
result in minor or moderate injury.
WARNING
Dangerous laser radiation
Always be aware of the hazard level of the device to be
connected.
Connect all optical fibers before switching on the radiation source.
Switch off the laser source before disconnecting the optical fibers.
Never look directly into the output of a laser source or into an
optical fiber connected to it.
Always cover unused ports.
Heed the normal precautions for working with laser radiation and
consider local regulations.

Chapter 1 Optical Spectrum Measurement
Safety information
MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 7
Specific
laser safety
To find out the appropriate laser classification, associated wavelengths
and optical power levels, see:
– the label on the SFP module
– the “Specifications” chapter in the operating manual of the SFP
In accordance with the laser classification, read and follow the
instructions given in the laser safety warnings below.
Laser classification of the SFP transceiver in the SFP slot
WARNING
Invisible laser radiation
Laser radiation can cause irreparable damage to eyes and skin.
Follow the laser safety regulations that apply in your area.
Take note of the laser classification of the individual test module.
Take note of the laser classification or hazard level of the device
under test.
Make sure that you protect yourself and others from exposure to
laser radiation.
Never look into optical outputs of devices or into the plug end
surfaces (free ends) of optical fibers.
Always cover disconnected optical plugs or disconnected optical
cable connectors with protective caps.
Always switch off the instrument and disconnect it from any fiber
optic cables before inspecting or cleaning the optical cable
connectors.
Make sure that the fiber optic cables are disconnected from all
sources of radiation before they are cleaned or inspected and
ensure that they are not reconnected until cleaning or inspection
has been completed.
CAUTION
SFP laser classification
Use only class 1 laser products in the SFP slots.
However, the user is free to use any other SFP transceiver compatible
with the SFP Multi Source Agreement (MSA).
In this case you must observe the laser classification of the
inserted SFP transceiver and its safety instructions!

Chapter 1 Optical Spectrum Measurement
Safety information
8 MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
Safety instructions for class 1 laser products
Safety instructions for class 1M laser products
Optical
surfaces
Dust and fingerprints can damage optical surfaces, particularly when
such surfaces are pressed together. To protect the instrument and
cables, every cable should be cleaned before it is connected to the
instrument. The optical connectors on the instrument should also be
cleaned regularly.
– Before cleaning the optical surfaces please pay attention to the
notes on safe handling of fiber optical cables and optical
connectors.
– To clean the optical connectors, remove the test adapters, dab the
end surfaces of the plug pins with cleaning tape and blow out the
test adapter using compressed air.
– Always fit protective caps to optical connectors that are not in use.
Ventilation Please refer to the user manual of the MTS-5800 Base Unit for further
information.
Battery
operation
Please refer to the user manual of the MTS-5800 Base Unit for further
information.
CAUTION
Invisible laser radiation
Class 1 laser products are defined as safe in normal operation under
reasonably foreseeable conditions.
Although the laser radiation from a class 1 laser product will not
harm eyes or skin, follow the general laser safety instructions (see
General laser safety instructions) to ensure maximum safety
when working with laser sources.
WARNING
Invisible laser radiation
Viewing the laser output of a class 1M laser product with certain
optical instruments (for example eye loupes, magnifiers,
microscopes) within a distance of 100 mm may pose an eye hazard.
Do not expose eyes to the beam within a distance of 100 mm.
Do not view the laser output with optical instruments.
Follow the general laser safety instructions.

Chapter 1 Optical Spectrum Measurement
Start the COSA application
MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 9
Start the COSA application
The fiber to be tested is connected to the optical connector.
1. Select the Fiber Optics button.
2. Select on the Home button.
3. To start the COSA application, select the COSA button.
Configuration
After connecting the fiber to be tested to the optical connector, you must
select the COSA module (see the Base Unit manual).
To configure the Base Unit in preparation for a COSA test on a fiber,
press the SETUP button. Two configuration procedures are available:
–“Test Auto WDM mode”
In this case the parameters are selected automatically.
–“Manual configuration”
In this case you may define your own configuration.
Test Auto WDM
mode
1. Press the Test Auto WDM softkey.
Following configuration will automatically be set.
Parameter Setting
Acquisition settings
Sweep Single
Measurements settings
Channel detection Permanent
Signal threshold Auto
Splitter compensation No
Results screen settings
Grid default = last value used
Alarms No
Table notes No
Unit nm

Chapter 1 Optical Spectrum Measurement
Configuration
10 MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
In case of any parameter setting the Test Auto WDM softkey appears.
Manual
configuration
Instead of selecting the Test Auto WDM mode the configuration
parameters can be set manually.
The parameter to be modified must be selected by means of the direction
keys . The possible options then appear on the screen: make your
choice using the direction keys and . Alternatively, change the
parameters via the touchscreen.
The various parameters proposed are defined below.
Fig. 2 Test Auto WDM softkey (1)
1
Fig. 3 Configuration for optical spectrum measurements.
(The softkeys available depend on the grid settings.)

Chapter 1 Optical Spectrum Measurement
Configuration
MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 11
Acquisition
parameters
Sweep
Number of sweeps
– In Statistics mode: between 2 and 1000
– In Drift mode: between 2 and 10000
Wait Period
The Wait Period parameter allows to enter a wait period prior to the
measurement start (in Statistics and Drift mode only).
s
Continuous There will be a measurement with refreshment of
the trace and real time display of results.
Single There will be one single measurement and the
display of its results.
Statistics In this mode, the number of samples concerned by
statistics must be entered (next parameter).
Drift For measuring power and wavelength over time.
The number of sweeps and the latency between
the sweeps need to be set.
NOTE
For Drift measurements a Grid needs to be defined and the Channel
Detection parameter is set to Grid.
Up to ... Increments of ...
1 minute 5 seconds
10 minutes 1 minute
60 minutes 5 minutes
24 hours 1 hour

Chapter 1 Optical Spectrum Measurement
Configuration
12 MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
Analysis
parameters
Channel
Detection1
Fig. 4 Analysis parameters
NOTE
Those parameters are only linked to the current active fiber.
1. Attention: All modification of these parameters has immediate repercussions on the trace and entails the loss of
the measurement statistics.
Grid The grid serves as a detection reference: it must
therefore be ITU CWDM or Manual. The choice of
grid takes priority over the choice
Channel detection. For example, it is not possible to
choose Channel detection = Grid, if the option
selected for the grid is «None» or «Conventional».
Permanent Automatic detection of the channel on each
acquisition. In this mode the channels are always
detected without making a reference measurement.

Chapter 1 Optical Spectrum Measurement
Configuration
MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 13
Signal threshold1 Threshold for detection of channels (see "Channel detection threshold"
on page 26).
Splitter
compensation
When the measurement is accessed by a splitter, it is possible to
compensate for the loss introduced by this element and to display the
value measured before or after it.
Go to the Splitter compensation line to display a sub-menu proposing
the following options:
NOTE
At the end of an acquisition in permanent mode, it is possible to
create a grid on the basis of the channels detected. To do this, press
the softkey Adopt Grid in the SETUP menu.
Auto – The threshold is determined automatically.
– To set to Auto: set threshold to -55 dBm.
Manual – Editable from -54.9 to +10 dBm.
– To modify values: use direction keys or Edit
Number.
NOTE
Modification of the parameters Channel selection and Signal
threshold will only modify the results if the WDM module present is
the one that was used for the acquisition.
Value1 Yes: activation of compensation and choice of its value
using the keys and : or the numeric keypad : from
1 to 30 dB (by increments of 1) or 1 to 99% (by
increments of 0.1%).
Unit Choice of compensation in dB or as a percentage of
the value measured.
For example, with a 10 dB splitter, the results will be
augmented by 10 dB. The trace will be offset upwards
by 10 dB. A channel measured at -30 dBm will be
displayed -20 dBm.

Chapter 1 Optical Spectrum Measurement
Configuration
14 MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
Parameters of
display and
analysis of the
results
Grid 1. Go to the Grid line to access the Grid sub-menu.
2. Select the Type line to see the different choices and modify them if
required.
Five possible types of grid are proposed with different corresponding
values, some of which are fixed or non-applicable, others editable.
The type Conventional and the option None do not give access to the
parameters of the Grid sub-menu; the others give access to certain
options, as shown in the table of the figure.
Fig. 5 Display parameters
NOTE
Those parameters are valid for all traces present on the screen.

Chapter 1 Optical Spectrum Measurement
Configuration
MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 15
Alarms When Channel Selection is positioned on Grid, it is possible to activate
an alarm system. This system is based on a system of thresholds. Any
measurement results that exceed these thresholds are displayed in red
in the table, and the icon appears at the top right of the screen. If all
the results are within the thresholds (no result is in red), the icon
becomes .
To activate the alarm system, go to the Alarms line and select
Active.
None Conventional ITU CWDM Manual
Grid name – – Editable Editable
ITU standard – – G.694.2 N/A
First ITU channel
(with display in nm)
– – Editable, from 1271 to 1611 nm,
by increments of 20 nm
N/A
Channel spacing – – 20 nm N/A
Number of
channels
– – Editable, from 1 to 19 by
increments of 1
Editable from
1 to 256
Define channels
– – Sub-menu accessible to display the
wavelengths of each channel, name the band,
and name each channel.
NOTE
The maximum real number of channels for ITU grids depends on the
value selected for the first channel and the spacing between the
channels.
NOTE
It is possible to display the grid with the View Grid softkey. A table
appears showing the channel number, the name of the channel, the
reference wavelength and the alarm thresholds for delta frequency,
minimum power and maximum power.

Chapter 1 Optical Spectrum Measurement
Configuration
16 MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
Thresholds can then be set (using the direction keys or numeric keypad),
to global level or to the level of each channel:
Global alarms
Channel alarms
Fig. 6 Alarm parameters
Number of channels Yes/No
Delta channel power1
1. Max. acceptable variation between max. power and min. power on all channels
“No” or threshold modifiable from
0.1 to 60 dB (for “No” set threshold to Min)
Composite power2
2. Maximum composite power
“No” or threshold modifiable from -59.9 dBm
to +20 dBm (for “No” set power to Min)
Max channel offset1
1. Wavelength drift. Selection of the alarm on the basis of the value of Delta Offset
Yes/No
Min channel power2
2. The values are then defined in P Min
Yes/No
Max channel power3
3. The values are then defined in P Max
Yes/No
Channel Number From «001» to the max. number of
channels.
Channel Value Display of the wavelength of the channel
number selected
Delta Offset4
4. Delta of frequency
From 0 to 10 nm
P Min5
5. Minimum power
From -55 dBm to P Max
P Max6
6. Maximum power
From P Min to +10 dBm

Chapter 1 Optical Spectrum Measurement
Configuration
MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01 17
Notes Table Here the display can be configured and it can be specified whether or not
it is possible to enter a note for each channel (see "Table notes" on
page 32):
Unit Here the units of the x axis can be selected:
Table Content Here the table content can be selected.
Manual Allows to manually enter a note for each channel in
the results table.
No Notes function is disabled.
nm Wavelength in nm
THz Frequency in THz
Fig. 7 Unit parameters
Fig. 8 Table Content parameters

Chapter 1 Optical Spectrum Measurement
Configuration
18 MTS / T-BERD 5800 • COSA-4055 • User Manual 2016.01
Link
Description
Define the parameters in the Link Description menu and add a
comment.
Fig. 9 Link Description parameters