Reduction of dispersion effects in optical transmission fibre systems
AssigneeNortel Networks Limited
InventorsRobert K. Brimacombe, David R. Walker
Life of this patent
Estimating the term…
Abstract
The effects of dispersion of light on a link having an optical transmission fibre characterised by positive dispersion and large positive relative dispersion slope can be reduced by employing a sufficient length of dispersion compensating fibre (“DCF”) so that dispersion slope on the link is substantially nulled and the net dispersion of the link is made negative. Optical signals launched on the link with a positive chirp will be compensated for by the net negative dispersion.
Claims20
A communication link having reduced dispersion effects comprising:
- an optical transmission fibre with a positive dispersion and a large positive relative dispersion slope;
- and
- at least one dispersion slope compensation module (“DSCM”) operatively coupled to said optical transmission fibre, each said DSCM having a dispersion compensating fibre (“DCF”), said at least one DSCM providing DCF of a length sufficient that dispersion slope on said link is substantially nulled and net dispersion on said link is negative.
A kit for a communication link having an optical transmission fibre with a positive dispersion and large positive relative dispersion slope, comprising:
- at least one dispersion slope compensation module (“DSCM”) having a dispersion compensating fibre (“DCF”) such that said at least one DSCM provides a length of DCF sufficient so that, once said at least one DSCM is installed on said link, dispersion slope on said link is substantially nulled and net dispersion on said link is negative;
- and
- at least one positive chirp transmitter for launching optical signals on said link.
A communication link comprising:
- at least one length of optical transmission fibre having a positive dispersion and a large positive relative dispersion slope for carrying a plurality of frequency multiplexed optical channels;
- at least one dispersion slope compensation module (“DSCM”) having a length of dispersion compensating fibre (“DCF”) so that net dispersion slope along said link is substantially nulled and net dispersion of said link for said optical channels is negative;
- at least one positive chirp transmitter, said at least one positive chirp transmitter for launching each said channel.
A method for reducing effects of dispersion of optical signals on a communication link having an optical transmission fibre with positive dispersion and a large positive relative dispersion slope, comprising:
- passing said optical signals through a sufficient length of dispersion compensating fibre (“DCF”) having a negative dispersion and negative dispersion slope so that dispersion slope of said link is substantially nulled;
- where, in consequence of said length of DCF, net dispersion on said link is negative, launching said optical signals on said link with a positive chirp.
A method for transmitting optical signals comprising:
- passing said optical signals through an optical transmission fibre with a positive dispersion and a large positive relative dispersion slope;
- and
- passing said optical signals through a sufficient length of dispersion compensating fibre (“DCF”) having a negative dispersion and a negative dispersion slope so that dispersion slope on said link is substantially nulled and net dispersion on said link is negative.
A method of designing a communication link having an optical transmission fibre with a positive dispersion and large positive relative dispersion slope comprising:
- choosing a length of dispersion compensating fibre (“DCF”) of sufficient length so that dispersion slope on said link is substantially nulled and net dispersion on said link is negative;
- and
- choosing at least one positive chirp transmitter for launching optical signals on said link.
Dependencies are inferred from the claim text.