Tunable dispersion slope compensation for 40-Gb/s WDM systems using broadband nonchannelized third-order chirped fiber Bragg gratings

• Published in: Journal of lightwave technology Vol. 20; no. 12; pp. 2259 - 2266
• Main Authors: Song, Y.W., Pan, Z., Motaghian Nezam, S.M.R., Yu, C., Wang, Y., Starodubov, D., Grubsky, V., Rothenberg, J.E., Popelek, J., Li, H., Li, Y., Caldwell, R., Wilcox, R., Willner, A.E.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.12.2002; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Bandwidth; Bit error rate; Bragg gratings; Broadband; Delay effects; Detection, estimation, filtering, equalization, prediction; Dispersions; Exact sciences and technology; Fiber gratings; Fibers; Information, signal and communications theory; Optical fiber communication; Optical fiber dispersion; Optical fibers; Signal and communications theory; Signal, noise; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Terrorism; Transmission and modulation (techniques and equipments); Tuning; Wavelength division multiplexing; Wavelengths; Performance evaluation; Chirp; optical fiber communications; Optical telecommunication; third-order fiber Bragg grating; Bragg grating; Wavelength division multiplexing; Equalization; Broadband grating; Wide band; Optical transmission; tunable dispersion slope compensation; wavelength-division-multiplexed (WDM) system; Optical fiber communication; Light dispersion
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2002.806772

We demonstrate tunable dispersion slope compensation using broadband nonchannelized third-order chirped fiber Bragg gratings (FBGs) for 40-Gb/s wavelength-division-multiplexed (WDM) systems. The slope is tuned by stretching as it has a third-order time delay variation with wavelength, and thus a second-order dispersion-wavelength curve. Calculation results include the examples of the slope tuning in addition to the interchannel dispersion differences and the slope tuning ranges with respect to the wavelength in a single grating. To verify the functionality of the third-order grating, we prepare a third-order grating with a dispersion variation of up to 400 ps/nm over the 3.5-nm usable bandwidth, and a dispersion slope tuning range of /spl sim/65 ps/nm/sup 2/ is achieved. For 40-Gb/s systems, two new gratings are designed and inversely cascaded to eliminate the inherent errors originating from the deleterious higher-order dispersion components in a single grating. The slope tuning range is -20 to +20 ps/nm/sup 2/ over the 5-nm usable bandwidth. A /spl sim/10-dB power penalty improvement is achieved and the BER floor is eliminated for the worst-case channel after transmission through a 170-km link using dispersion shifted fiber (DSF) with a 4/spl times/40-Gb/s RZ data stream.