IMPACTS OF PUMP MODULATION ON GAIN AND NOISE OF DISTRIBUTED RAMAN AMPLIFIER
Keywords:
Raman, optical amplifiers, pump modulation, optical communications, wavelength division multiplexingAbstract
Effects of pump modulation technique of two-pump wavelength Raman fiber amplifier were presented. The pump wavelength modulation was achieved using pulsed-drive current from the laser diode controller. The selection of modulation frequency was critical in this pumping technique which created temporal gain variations. The maximum temporal gain variation of 0.45 dB was recorded at 10 kHz modulation frequency while this factor was eliminated at higher frequencies; 300 kHz. The effective noise figure also degraded when utilizing this pumping scheme due to the arising of amplified spontaneous emission.
References
Bromage, J., Winzer, P.J., Nelson, L.E., Mermelstein, M.D., Horn, C., and Headley, C.H. (2003). Amplified spontaneous emission in pulsed-pumped Raman amplifiers. IEEE Photon. Technol. Lett., 15(5):667-669.
Emori, Y., Tanaka, K., and Namiki, S. (1999). 100 nm bandwidth flat-gain Raman amplifiers pumped and gain-equalized by 12-wavelength-channel WDM laser diode unit. Electron. Lett., 35(16):1,355-1,356.
Fludger, C.R.S., Handerek, V., Jolley, N., and Mears, R.J. (2002). Novel ultra-broadband high performance distributed Raman amplifier employing pump modulation. Proceedings of the Optical Fiber Communication Conference; March 17- 22, 2002; Anaheim, California, USA, p. 183-184.
Kidorf, H., Rottwitt, K., Nissov, M., Ma, M., and Rabarijaona, E. (1999). Pump interactions in a 100 nm bandwidth Raman amplifier. IEEE Photon. Technol. Lett., 11(5):530-532.
Mollenauer, L.F., Grant, A.R., and Mamyshev, P.V. (2002). Time-division multiplexing of pump wavelengths to achieve ultrabroadband flat, backward pumped Raman gain. Opt. Lett., 27(8):592-594.
Winzer, P.J., Sherman, K., and Zirngibl, M. (2002a). Time-division multiplexed Raman pump experiment using a tunable C-band laser. IEEE Photon. Technol. Lett., 14(6):789-791.
Winzer, P.J., Bromage, J., Kane, R.T., Sammer, P.A., and Headley, C. (2002b). Temporal gain variations in time-division multiplexed Raman pumping schemes. Proceedings of the Conference on Lasers and Electro-Optics; May 19-24, 2002; Long Beach, California, USA, p. 428-430
