公开(公告)号：JP2001343673A

公开(公告)日：2001-12-14

申请号：JP2001057526

申请日：2001-03-02

Applicant: LUCENT TECHNOLOGIES INC

Inventor： HANSEN PER BANG ,  LEE ROBERT B ,  PARK SEO Y ,  REED WILLIAM ALFRED ,  STENTZ ANDREW J

IPC: G02B6/02 ,  G02F1/35 ,  H01S3/06 ,  H01S3/30 ,  G02B6/16

Abstract: PROBLEM TO BE SOLVED: To avoid the instability of modulation and the effect of the four-wave mixing in a Raman-amplification optical transmission system. SOLUTION: A transmission fiber which is used in the Raman-amplification optical transmission system is constituted so as to exhibit specific characteristics for restricting the instability of modulation and the four-wave mixing in an amplification area and, as a result, noise constituting elements existing in the transmission system are reduced.

公开(公告)号：CA2335891A1

公开(公告)日：2001-09-03

申请号：CA2335891

申请日：2001-02-13

Applicant: LUCENT TECHNOLOGIES INC

Inventor： STENTZ ANDREW JOHN ,  REED WILLIAM ALFRED ,  PARK SEO Y ,  LEE ROBERT B ,  HANSEN PER BANG

IPC: H01S3/30 ,  H04B10/17 ,  H04B10/18 ,  G02F1/39

Abstract: A transmission fiber for use in a Raman amplified optical communication system is formed to exhibit certain characteristics that limit modulation instability and four-wave mixing in the amplification region, thus reducing the noise component present in the transmission system. In particular, the group-velocity dispersion (denoted as D and measured in terms of ps/nm-km) is restricted to be either non- positive or greater than +1.5ps/nm-km in the pump wavelength range of interest (a typica l pump wavelength range being 1430-1465nm). Preferably, the magnitude of the dispersion is kept below a value of 10 ps/nm-km in the signal wavelength range of interest (e.g., the "C" band or "L" band). Four-wave mixing is reduced by ensuring that the zero - dispersion frequency of the transmission fiber is not centered between the pump frequency and a frequency experiencing Raman gain.