Effects of Fibre Bragg Grating bandwidth on multiwavelength Brillouin-Raman fiber laser in the ring cavity.

摘要

The application of Multiwavelength fiber sources in wavelength division multiplexing (WDM) for broadband transmission is of great interest in telecommunication research work. Multiwavelength lasers utilize a hybrid technology such as Brillouin-erbium fiber laser (BEFL) and Brillouin-Raman fiber laser (BRFL). The BRFL (Brillouin Raman fiber laser) comprises of two gain effects, the Brillouin gain and the Raman gain, both of which can be obtained simultaneously in the same optical fiber. The advantages of Raman amplification is that they can work in any wavelength band by simply choosing the appropriated pump wavelength. Raman amplifiers have a very large bandwidth. The applications of Raman amplification in WDMs and in long-haul optical telecommunications have been widely studied and since the C-band is already congested, the addition of L-band communication window is highly desirable. In this research work, Multiwavelength BRFL by integrating five different bandwidth Fiber Bragg Gratings (FBGs) in the L-band is proposed. The configuration of the experimental setup is based on a ring-cavity design pumped with 1480 nm Raman pump source. FBGs used in the aim to reduce the self lasing cavity modes, are of 5, 10, 20, 30 and 40 nm bandwidths. The medium used for Raman and Brillouin effects is 19km dispersion compensating fiber (DCF). The five different setups will be studied extensively in terms of number of channels produced, the tuning range and signal to noise ratio. Finally, the effect of FBG's bandwidth on the Multiwavelength laser performance can be concluded.