OADM Workshop
23-24 April 1998
Characterization of Grating Based OADM
J. Chawki, France Télécom
F. Vincensini, Pirelli
Introduction:
The METON project develops and demonstrates an application of wavelength routing in a
metropolitan optical network. The project is focusing on the network infrastructure and is
developing a manageable optical network layer to support ATM networks. The network will
serve many customers with broadband services in the metropolitan area.
Fig1: METON Network
The METON WDM Layer is a 2 rings architecture linked by an Optical Crossconnect. 5
different technologies of OADM are used : Acoustooptic, InP, Fabry Perot, Bulk Grating and
Fiber Grating.
This paper presents the characterization of 2 Pirelli OADM Nodes, based on grating
technologies.
After a brief description of node Integration, experimental results on node parameters, Insertion
Losses, crosstalk, power penalties and protection systems performances are presented.
1. BULK GRATING OADM NODE :
Description :
The BulK grating OADM Node is a flexible, Monodirectional Ring Node. It allows the choice
of Add Drop functionality on 2=1552.52 nm or 4=1558.98 nm, by Hardware or Software
Control and performs automatic Ring protection. Local Trafic is inserted with Pilot Tone
addition.
It provides a local craft Interface via RS32 cable and remote control through an Ethernet
Network, for alarms, control and management.
Performances measured were :
Maximum Insertion Losses are 9.2 dB in transit, 8 dB in reception and 7.2 dB in insertion.
Interchannel Isolation is more than 60 dB, and Intra Channel Crosstalk over 55 dB.
Delay for protection is less than 50 ms. Power Penalty at 2.5 Gbit/s was less than 0.5 dB in any
configuration.
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23-24 April 1998
Fig 2 : Bulk Grating OADM Node
OADM Workshop
Fig3 : Bulk Grating OADM Board
2. FIBRE GRATING OADM NODE :
Description:
The Fibre grating OADM Node is a fixed, Bidirectional Ring Node. It performs Add Drop
functionality on 1=1549.32 nm and performs automatic Section protection. Local Trafic is
inserted with Pilot Tone addition.
It provides a local craft Interface via RS32 cable and remote control through an Ethernet
Network, for Alarms, Control and Management.
Performances measured were:
Maximum Insertion Losses are 4.5 dB in transit, 6 dB in reception and 5 dB in insertion.
Interchannel Isolation is more than 50 dB, and Intra Channel Crosstalk over 25 dB.
Delay for protection is less than 50 ms. Power Penalty at 2.5 Gbit/s was less than 0.5 dB in any
configuration.
Fig 4 : Fibre Grating OADM Node
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Fig5 : Fibre Grating OADM Board