Raman Amplifier

As the demand for higher transmission capacity in wavelength division multiplexing (WDM) systems increases, channel speed, channel number, and spectral efficiency need to be upgraded. To this end, Raman fiber amplifiers (RFA) have become essential in overcoming the limitation of bandwidth and noise figure. The dissertation focuses on the experimental investigation of Raman fiber amplifiers. The followings are the main contents:1. The main principle, characteristics and classification are summed up. And the performance parameters are also listed.2.The gain spectrum of Raman fiber amplifier is investigated, especially the gain flatness for C-band and C+L band Raman fiber amplifier. We got 12dB gain with gain flatness of less than 0.8dB by combining three pump wavelengths in C-band. Furthermore, the gain flatness of C+L band Raman amplifier is also experimentally investigated.3. The SBS phenomenon in discrete and distributed Raman fiber amplifiers have been studied in detail.4. Gain saturation problem is very serious in EDFA. But few people realized that it is also serious in Raman fiber amplifier, especially in discrete Raman amplifier. We investigated Gain saturation of discrete and distributed Raman amplifier in detailed in this paper.