Reach extension of passive optical networks using semiconductor optical

amplifiersA E Kelly, C. Michie, I. Andonovic, J. McGeough, S

Kariaganopoulos

Standard Passive Optical Networks

GPON 1:32Reach 10-20km

Extended Reach Passive Optical Networks

Electronic regeneration cannot be used as it results in Preamble erosion due to burst mode locking time

Passive Optical Networks 1300nm backhaul

transmitter 1310nm

VOA1 SOA VOA2

20 nmfilter

receiver 1310nm

•VOA1 represents access loss – split plus some link loss•VOA2 predominately trunk loss•1300 nm and 1.25/2.5 Gbit/s; dispersion neglected

insertion loss α

Significant ASE levels

Power BudgetSimple linear model

2

22

tot

inPRSNR

PinPIN or APD

.)(4)(2

22

2

2

BFRkT

BIRPe

PRISNR

NL

Drec

in

TOT

P

shot noise terms thermal noise

receiver Noise Figure

pin

Power BudgetSimple linear model

2

22

tot

inPRSNR

PinPIN or APD

shot noise termsthermal noise

receiver Noise Figure

APD

BFRkT

BIRPFeM

PRMISNR

NL

DinA

in

TOT

P

)(4)(2 2

222

2

2

APD Multiplication and Noise Factor

SNR modified to account for ER of transmitter – at best 10 dB

Power Budget

e

eAVE

r

rPQ

1

120

21

Baseline calculations

APDNeo PhotonicsPTB3J88-5638T-SC/PC+

pin – OCP- TRXAG1M

data modelled for commercial pin/APD

1.E-11

1.E-10

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

-30.00 -28.00 -26.00 -24.00 -22.00 -20.00

Receiver Power, dBm

BE

R

BTB

10dB ER

1.E-11

1.E-10

1.E-09

1.E-08

1.E-07

1.E-06

-36.00 -34.00 -32.00 -30.00 -28.00 -26.00

Receiver Power, dBm

BE

R

BTB

BTB ER 10 dB

Inclusion of Amplifier

Build upon a model of the SNR to include the noise terms associated with amplifier

2222221 ASEASEASESASEST

22220 ASEASEASET

Extinction Ratio further degraded due to ASE

ASEASE PPP /)( 1

1

120

21

AVEPQ

transmitter 1310nm

VOA1SOA

VOA2

20 nmfilter

receiver 1310nm

insertion loss α

Significant ASE levels

0v

APD based Receiver

Assumptions– -28 dBm sensitivity for BTB un amplified with 10 dB ER– M=10– thermal noise estimated to give sensitivity of -28dBm

for 10-10 BER (value specified on data sheets)– Psat of SOA +13 dBm– NF 7 dB

Amplified APD Receiver

1.E-13

1.E-12

1.E-11

1.E-10

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

-45.00 -40.00 -35.00 -30.00 -25.00

Signal Power, dBm

BE

R

BTB infinite ERBTB 10 dB ER0.8 nm filter10 nm filter20 nm filter20 nm no ER deg

Baseline0.8nm filter10 nm filter

20 nm filter

20 nm filterER not considered

Influence of Optical Filtering

-40.00

-39.00

-38.00

-37.00

-36.00

-35.00

-34.00

-33.00

-32.00

-31.00

-30.00

0 5 10 15 20

Optical Filter Bandwidth, nm

Rec

eive

r P

ower

, dB

m (

BE

R10

e-10

)

0

1

2

3

4

5

6

7

8

9

10

Ext

inct

ion

Ra

tio, d

B

Prec pin

Prec APD

pin ext dB

APD ext dB

Post Amplifier Losses

Position amplifier to compensate for splitting and reach lossesSOA Psat limited to +13 dBmGain adjusted accordingly max

max

1G

GPG

Gin

Splitter(Access)

lossSOA Backhaul

20 nmfilter

OLTreceiver 1310nm

insertion loss αONT

System Power Margins

0

5

10

15

20

25

30

35

40

0 5 10 15 20 25 30 35

Loss into Amplifier, dB

Lo

ss

aft

er

am

plif

ier,

dB

0

1

2

3

4

5

6

7

8

9

10

Ex

tin

cti

on

Ra

tio

, Po

we

r p

en

alt

y, d

B

Post Amplifier Loss

Unamplified Signal

Ppenalty

ext dB

pre-amp margin

booster margin

mid span margin benefit

GPON

Margin Enhancement for Amplified GPON

0

5

10

15

20

25

30

0 5 10 15 20 25 30 35 40

Loss into Amplifier, dB

Sys

tem

Ma

rgin

Enh

anc

emen

t, d

B

128 split

-20

0

20

40

60

80

100

1 10 100 1000 10000

SplitRatio

Bac

khau

l Dis

tanc

e, k

m

Amplified Reach

Unamplified Signal

64 split128 split

32 Split64 Split512 Split

Psat limited

Gain limited

NF limitedGPON: 32 split

Distance versus number of users for each case

Experiment

VOA SOA VOAl

Channel DropOSA

(filter)

1300 nmreceiver

1300 tx

Experimental Validation

1.E-10

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

-40.00 -38.00 -36.00 -34.00 -32.00 -30.00 -28.00 -26.00

Signal Power, dBm

BE

R

BTB Theory10 nm theory20 nm theory20nmBTB10 nm

Constant BER curve with filter width

-40

-39

-38

-37

-36

-35

-34

-33

-32

-31

-30

0 5 10 15 20

Optical Filter Bandwidth, nm

Rec

eive

r P

ower

, dB

m (

BE

R10

e-10

)

0

1

2

3

4

5

6

7

8

9

Ext

inct

ion

Ra

tio, d

B

Prec APD

Sens

APD ext dB

Experimental Margin Enhancement

-30

-20

-10

0

10

20

30

40

50

60

0 5 10 15 20 25 30 35

Loss into Amplifier, dB

Pos

t Am

plifi

er M

argi

n, d

B

-35

-30

-25

-20

-15

-10

-5

0

Po

wer

at

Rec

eive

r, d

Bm

Loss Post Amp TheoryLoss Post Amp ExptUnamplifiedP BER10-9 EXPTP 10-9 theory

Conclusions

• Number of users and backhaul distance can be considerably increased by using SOA based amplification

• Required SOA specification depends on placement within network

• A single SOA cannot meet these requirements • Variable gain clamping schemes?

Key PublicationsRussell P. Davey, Daniel B. Grossman, Michael Rasztovits-Wiech, David B. Payne, Derek Nesset, A. E. Kelly, Albert Rafel, Shamil Appathurai, and Sheng-Hui Yang “Long-Reach Passive Optical Networks” Journal of Lightwave Technology, Vol. 27, Issue 3, pp. 273-291 February 2009 (invited tutorial paper)High Performance Semiconductor Optical Amplifier Modules at 1300nm”A.E.Kelly, C.Michie, I.Armstrong, I.Andonovic, C. Tombling, J.McGeough and B.C.Thomsen, Photon.Tech.Lett, Vol.18, No.24, pp 2674-2676, 2006“The Dynamic Gain Modulation Performance of Adjustable Gain-Clamped Semiconductor Optical Amplifiers (AGC-SOA)” Liu, L. Michie, C. Kelly, A. E. Andonovic, I., Journal of Lightwave Technology , Volume: 29 Issue: 22 pp 3483 – 3489, 2011.