A new technique is proposed to simultaneously amplify signals and equalize power unbalance caused by Raman-induced crosstalk among optical channels in the 1.3-μm band. The crosstalk is induced in GeO2-doped silica fibers due to the Raman-gain coefficient with a positive slope below the peakfrequency shift of 440 cm-1. Highly doped GeO2 silica fiber, however, shows a negative slope across the band between 440 cm-1 and 490 cm-1. We propose expansion of the Raman-gain band with a negative slope over the bandwidth of 150 cm-1 using multiple pumps. Utilizing the negative gain slope of the proposed band, simultaneous amplification and power equalization was theoretically demonstrated for 30 channels in the 1.310-1.345 μm region without external filters.
Bibliographical noteFunding Information:
Manuscript received July 27, 2000; revised October 25, 2000. This work was supported in part by UFON, an ERC program sponsored by KOSEF, and BK21 program, supported by MOE in Korea. The authors are with the Department of Information and Communications, Kwangju Institute of Science and Technology, Kwangju 500-712, South Korea (e-mail: firstname.lastname@example.org). Publisher Item Identifier S 0733-8724(01)01889-8.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics