1

Comparison of Gamma Radiation Effect on

Erbium Doped Fiber Amplifiers

Communications Inc.

E. Haddad1, E. Haddad1,V. Poenariu1, K. Tagziria1, W. Shi1, C. Chilian2,

N. Karafolas3, C. Bringer3, M. Sotom4, M. Aveline4

1 MPB Communications Inc., Pointe Claire, Québec, Canada;

2 Ecole Polytechnique de Montréal, Montréal Québec, Canada;

3 Optoelectronics Section, European Space Agency (ESA),ESTEC, The Netherlands,

4 Thales-Alenia-Space , France

International Conference on Space Optics,

ICSO 2016 Biarritz, France ; 17 - 21 October 2016

Introduction

Main objective: Leverage the current Erbium and Erbium

Ytterbium amplifier to space qualified product

Challenge: Gamma radiation effect is the main limiting factor

Main motivation –An increase interest with planned large

constellations being built by International Consortiums

(Airbus, Facebook, Google, Inmarsat , Laser-Light, Leosat,

Oneweb, Thales-RUAG)

2

Optical Amplifiers in Space-1

Optical Telecom satellite communications

• Satellite to drone or airplane, the drone or airplane being the

liaison between the satellite and the ground segment

• Satellite to High altitude Platforms (HAP), the HAP being the

liaison between the satellite and the ground segment

• Optical inter-satellite Link (LEO-LEO) and (LEO-GEO) New

investment within the Optical telecom satellite

• Fast transfer of data close to real time data from Earth

Observation satellite images (a few minutes instead of 90

minutes currently)

3

Optical Amplifiers in Space-2

• Intra telecom satellite optical applications- Flexible telecom

repeater with microwave photonic MxN cross-connect. The

Optical Wideband Receiver (OWR) contract from ESA to

Thales-Alenia-Space (MPB built the Medium Level Optical

Amplifier MLOA in this project)

• Boost the optical signal in Photonics payloads

• Sensor application in non-Telecom satellites (e.g. Proba series

satellites- MPB Built the first Fiber sensor system in space- It

includes an Optical Amplifier).

• Various Instruments where a very low noise is a must (e.g.

MIRAS on SMOS)

4

5

Schematic of an Optical Erbium doped Fiber Laser

Laser Diode

pump

Isolator Isolator

output

input

WDM

EDF

Backward

pumping

Photo

Dio

de 1

Laser Diode

pump

Forward

pumping

Input source

Photo

Dio

de 2

MPB Amplifier Product LineErbium and Erbium Ytterbium Amplifiers since the 1990s

Bench Top Instruments

Credit card size6

Gain Modules

Space Qualification Tests of MPB’s EDFAs

EDFA qualifiedGain

(dB)

Year of

qualifi

cation

TRL

Now

TRL

End of

Mission

(year)

EDF Tunable laser for the Fiber Sensor Demonstrator:

- Flying on Proba2 ESA’s satellite since Nov 2009

- Completely functional after 6 years

- Fiber sensors: 4 lines x6 fiber sensors each,

12 2005 7 8

6 EDFAs tested by Alter-Technologica and TAS for ESA

including radiation test15 2007

5-6

( 2008)

5-6

( 2008)

EDFA light source 15 dB gain, for Fiber sensor on

Atmospheric Reentry mission (ESA-DLR)17 2014

6

(2015)

6

(2016)

Medium Level Optical Amplifier (20 dB gain) for ESA-

/Thales-Alenia Space20 -21

2013-

2015 4 5-6

On-going contract-1 (ESA): Medium power and Low

Noise amplifiers15-28

2014-

20164 5-6

On-going contract-1 (ESA): High power amplifier ( LEO

satellite to ground, Drones or High Altitude Platform)

>40

dBm

2015-

2017 3-4 5-6

7

Gamma radiation Tests performed by MPB

8

Parameter Polytec-1 Polytec-2 ESTEC-1 ESTEC-2 Alter-Tech.

LocationMontreal,

Can.

Montreal,

Can.

Noordwijk,

Neth.

Noordwijk,

Neth.Sevilla, Spain

Radiation source Sc-46 Sc-46 Co-60 Co-60 Co-60

Date January 2013July- Nov.

2013

May-June

2014

Nov.-Dec.

2015

August 2016

(not ready

Test Duration (Days) 20 129 12 43 23

Dose Rate (rad/h) 235Deb:52 /

Fin:18 363 108 215

Total Dose (Krad) 101.5 125.2 106.7 110.3 101

Total Dose (Gy) 1015 1252 1067 1103 1010

Total number of

Fibers4 3 22 25 15

Standard EDF tested Yes Yes Yes Yes Yes

PM-EDF tested No No Yes Yes (more) Radhard

EYDF tested No No Yes Yes (less) No

PM-EYDF tested No No No Yes Yes

Comparison of Sc-46 and Co-60

9

Parameter Sc-46 Co-60

Physical-Half-life (days) 83.8 days 1925.20

Maximum Beta Energy: (MeV) 0.357 (100%) 0.665 (100%)

Gammas ( MeV)

1.121 (100%) 1.33 (100%)

0.889 (100%) 1.17 (100%)

Half-Value Layer (HVL) for Lead Shielding

(mm Pb)[4]12.5 15.6

Exposure rate (R: cm2/m.Ci.h) Roentgens

per hour for a given activity in milliCuries

at a distance in centimeters

10.8 12.9

Schematics of the test set up with Sc-46

10

Lead

Cylinder EDF enrolled

on inner plastic

cylinder

Two fixed Sc-46 Sources

(3mm diameter)

Set up at ESTEC Co-60 laboratory

11

EYDFA pumped during radiation test -ESTEC

Low index polymer of the EYDFA

Parameters measured during the test

12

• Gamma radiation Level

• Total power ( 1525nm-1565nm) before and after radiation

measured by photodiode –one parameter

• Wavelength Spectra ( 1525nm-1565nm)before and after

radiation , measured with Optical Spectrum Analyzer (OSA)

• Noise Figure Spectra (1525nm-1565nm)before and after

radiation , measured with Optical Spectrum Analyzer (OSA)

Examples of total power, Test with Sc-46

13

Examples of spectra, Test with Sc-46

14

Examples of total power, second Test with Sc-46

15

-2.5

-2

-1.5

-1

-0.5

0

0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0

Op

tica

l Po

we

r V

ari

atio

n (

dB

)

Gamma Radition (krad)

Polytech2-EDFAs optical power variation with gamma radiation

AMP3, Active during radiation, Co-pump

EDF1-MPB, Active during radiation, Contra-pump

EDF1-MPB, Active during radiation, Co-pump

EDF1-MPB, Passive during radiation, Co-pump

Commercial fiber tests at ESTEC-1 and ESTEC-2

16

11 and 17 length of the EDF

Forward/Contra Pumped configuration

L/H pumping power 300 /750 mW

ESTEC-1: 360 rad/h. Total 100 krad ESTEC-2: 107 rad/h, Total 100 krad

Photo-bleaching effect on commercial PM-Fiber

17

Summary of the test of the EYDF

EYDF

Fiber

#

Company SpeciesState during

RadTest

Output

Power

Ref. (0

krad)

(dBm)

Output

Power

After 106

krad

(dBm)

Output Power

Reduction

After 106 krad

(dB)

1 A Standard Unpumped 28.8 26.7 2.1

2 BRadhard-1

(> 100 krad)Unpumped 27.05 26.55 0.5

3 BRadhard-1

(> 100 krad)Pumped 27.05 26.75 0.3

4 CRadhard-2

(up to 20 krad)Pumped 28.4 27.9 0.5

5 CRadhard-2

(up to 20 krad)Unpumped 28.49 27 1.49

18

Sensitivity of the fiber selection Two EDF almost similar in name from the same supplier

19

Conclusions-1

Is there radhard Fiber between the fiber tested (100 krad)?

• EDF: AMP3 Radhard (Gain loss< 1 dB), some commercial fibers “semi radhard” (Gain loss about 3-4 dB/100krad)

• EDF-PM: Only semi radhard including commercial product and AMP2-PM (preliminary results)

• EYDF: Many semi radhard, and at least one radhard

• EYDF-PM probably one radhard (preliminary) no semi-radhard ( losses about 6 dB)

20

Conclusions-2

21

It is possible to build space qualified fiber amplifier

• Selection of the fiber (semi-radhard)

• Optical and electronic circuit design (redundancy)

• Enclosure with materials protecting against radiation

Further Development- Objectives

• To build radhard optical EYDF amplifiers at 40-43 dBm (10-20W) with optimal conversion efficiency.

• Polarization Maintaining Fibers and components

• Build High Power EYDF Lasers > 40 dBm

• Space Qualification of High power amplifiers and lasers

22

FSD parameters evolution during the flight since last on-ground measurements

23

-8

-6

-4

-2

0

2

4

6

8

5

10

15

20

25

30

35

40

45

50

552009-0

9-0

1

2010-0

5-0

9

2011-0

1-1

4

2011-0

9-2

1

2012-0

5-2

8

2013-0

2-0

2

2013-1

0-1

0

20

14

-06

-17

2015-0

2-2

2

20

15

-10

-30

2016-0

7-0

6

Volta

ge[v

]

Tem

pera

ture

[C

]

Date

FSD Parameters Evolution before and during the Flight

Thermistor Interrogation Box AD590_1

Laser Diode1-Power (v)

Laser Diode2-Power (v)

Line1-FBG-Sensor-Pressure-Temp.

Line3-FBG Sensor-Thruster Temp.

Line4 FBG Sensor1-Tank

RADFET (X-rays)

+5V_Monitor (Test returns ½ value)

12V (Test returns ½ value)

-12V (Test returns ½ value)

the temperature follows the primary vertical axis (left side),

all the other parameters follows the secondary axis (right)

Calibration of Radfet vs total radiation

24

y = 3.0355E-03x - 1.2145E+02R² = 9.9335E-01

0

1

2

3

4

5

6

7

8

910/3

1/2

009

10/3

1/2

010

10/3

1/2

011

10/3

0/2

012

10/3

0/2

013

10/3

0/2

014

10/3

0/2

015

10/2

9/2

016

To

tal R

ad

iati

on

(kra

d)

Date

Total radiation received in the Fiber Sensor Demonstrator-Interrogation Module

RADFET (X-rays)

Linear (RADFET (X-rays))

FSD parameters vs radiation

25

0

1

2

3

4

5

6

-20

-10

0

10

20

30

40

50

60

0 1 2 3 4 5 6 7

Vo

lta

ge

[v]

Te

mp

era

ture

[C

]

Radiation (Krad)

Fibers Sensor Demonstartor Component parameters evolution in time

Temperature Sensor boxAD590_1

Laser Diode1-Power (v)

Laser Diode2-Power (v)

Line1-FBG-Sensor-Pressure-Temp.

Line3-FBG Sensor-ThrusterTemp.

Line4 FBG Sensor1-Tank

The fluctuations in the graph at ~4.5 krad and ~7 krad are due to temperature