Polarization Division
Multiplexing Emulatorw w w . k y l i a . c o m
i n f o @ k y l i a . c o m

PDME

1 – Description
The Polarization Division Multiplexing Emulator (PDME) is a device that enables to control the delay between
both polarizations. The PDME can be used to emulate Polarization Division Multiplexing (PDM) signal bylaunching a polarized signal with a given modulation format. At the output of the device the modulation
format will be emulated on both polarizations. For example, if QPSK is launched at the input, PDM-QPSK willbe emulated at the output. The PDME can also be used to emulate Polarization Mode Dispersion (PMD).
Several options are available on the PDME, such as ON/OFF switch, Variable Optical Attenuator, Variable
Optical Delay Line or long free space delay.

PDME (standard device)

PDME with VOA, VODL and SWITCH options

2 – Block diagram

delay ~ 10ns

input (PMF).

.
.

output (SMF).

Block diagram: PDME

www.kylia.com

PDME

1

PDME : Polarization Division Multiplexing Emulator

The incoming polarized signal is split in two parts with equal optical power. One of them is delayed of about
10ns then both parts are recombined such as their polarizations are orthogonal.
Several options are available on the product (see following chapters) to make the use of the PDME easier.

3 – Absolute maximum ratings
Parameter
Maximal optical input power
Storage temperature range
Humidity
Fiber bend radius

Symbol
OpIn
STR
RH

Min

Symbol
OWR
OTR

Min
1520
10Symbol

Min

Typ.

Max
300
4085

Unit
mW°C%
mm

Typ.

Max
1625
35

Unit
nm°C

Remarks/Conditions

Typ.
2.0

Max
3.0
4.0
1.0

Unit

Remarks/Conditions-10520Remarks/Conditions

Non condensing

4 – Operating conditions
Parameter
Operating wavelength
Operating temperature range

5 – Specifications
Parameter
Insertion PM fiber delay option
1Losseslong free space delay option
1
IL variation between both armsin PM fiber
Optical2
Delayin free space
Optical Return Loss
3
Variable Optical Delay range
3
IL variation over delay range
4
Variable Optical Attenuation accuracy
standard
Packaging size
5VODL option
SM (output)
Fiber Pigtail TypePM (input anddelayed arm)

ILΔIL

0.4
1020
ORL

35330
0.3
100 x 55 x 16216 x 92 x 40SMF-28

1.0
0.1

dBdBnsdB
psdB
dB
mm

3

PANDA PM1

measured over OTR and OWR
for long free space delay option
3
for VODL option
4for VOA option
5
excluding micrometer head or piloted actuator
2

www.kylia.com

PDME

2

PDME : Polarization Division Multiplexing Emulator

6 – ON/OFF switch option
The ON/OFF switch option enables to shut one arm of the PDME and thus the output signal modulation
format is the same as the input one.

ON/OFF switchinput (PMF)

delay ~ 10ns.

.
.

output (SMF).

PDME: ON/OFF switch option

7 – Variable Optical Delay Line (VODL) option
The VODL option enables to tune the delay over a 330ps range. Within this range the IL variations of thetuned arm will remain below 1dB.

.

input (PMF)

micrometer headfor delay tuning.
PMpatchcord

output (SMF).
delay ~ 10ns - 300ps VODLPDME: VODL option
The delayed arm required a PM patchcord. The PDME is provided with a 20cm patchcord. The user can
replace it by a longer one if larger delay is needed.
The delay tuning can be piloted using a motorized actuator driven by a controller. The controller iscompatible with the NEWPORT NSTRUCT Instrument Manager platform, simple and intuitive to use andconveniently accessible via USB.
www.kylia.com

PDME

3

PDME : Polarization Division Multiplexing Emulator

8 – Variable Optical Attenuator (VOA) option
To have the best emulation one main point is to have the same power in both arms before they arerecombined. Even if the difference is always low it may slightly vary depending on the wavelength used. The
VODL option has also a small effect (see previous chapter). With the VOA option, one can easily adjust thepower difference between both arms with 0.1dB accuracy and then get a perfect emulation.

micrometer headfor variable attenuation.

input (PMF)

micrometer headfor delay tuning.
PMpatchcord

output (SMF)

ON/OFFswitch.
delay ~ 10ns - 300ps VODL

micrometer head forvariable attenuation (VOA)
ON/OFF switch
delayed arm (to be linked
via a PM patchcord)
micrometer headfor delay tuning(VODL)
input (PMF)

output (SMF)

PDME: VODL + VOA + ON/OFF switch option

www.kylia.com

PDME4

PDME : Polarization Division Multiplexing Emulator

10 – Long Free Space Delay option
For some reasons it may be useful to have the delay between both polarizations made in free space insteadof fiber. With the long free space delay option, a delay up to 20ns can be realized without any optical fiber.
The additional IL induced by this set up will be below 1.0dB.

11 – Tunable Coupling option
The Tunable coupling option enables to adjust the splitting ratio of the PDME from 100/0 to 0/100. This canbe very useful if a precise 50/50 ratio is needed as it enables to easily adjust the power difference between
both arms with 0.1dB accuracy, just like the Variable Attenuator option but without adding losses.

tunablePM coupler.

input (PMF).
PMpatchcord.

output (SMF)

PDME: tunable coupling option

12 – Application note
The PDME can be used to emulate a POLMUX-QAM16 signal from a QAM16 signal.

QAM emulator
QAM16

POLMUX-QAM16

PM-DQPSKPDM emulator.

.

Emulation of a POLMUX-QAM16 signal from a PM-DQPSK signal

www.kylia.com

PDME5

PDME : Polarization Division Multiplexing Emulator

13 – Typical measurements
Here are the IL versus frequency measured at 10°C, 22°C and 35°C of a PDME with VODL option:

IL vs frequency for PDME with VODL option

14 – Fiber type and connectors
The PDME has a PM input fiber and a SMF output fiber. The fibers of the delayed arm are PM.
The devices can be proposed with any kind of connectors (FP/UPC, FC/APC, SC/PC, SC/APC, LC/PC, E2000/PC,
E2000/APC).

15 – Wavelength range
The PDME can be proposed at different wavelength range, from the visible to the IR. The device will be
operational on a wavelength range of a tens of nanometers centered on the wavelength required bycustomer.

16 – Custom productThanks to our free-space technology we can easily customize most of our product and so it is for the PDME.
Customer can feel free to ask for any customization they need. We will examine the request and do our best
to have a positive answer.

www.kylia.com

PDME

6

PDME : Polarization Division Multiplexing Emulator

17 – Package layout

PDME packaging

PDME: VODL + VOA + ON/OFF switch option

18 – Revision
dateMarch 21, 2013www.kylia.com

versionPDME V1.0

ObjectCreation

PDME

7