Optical fiber communication is the best transmitting data may be capable of Terabit per second data rate. No existing single communication system can make complete use of this speed. Many types of Optical amplifiers have been developed to amplify optical signal. EDFA is one of the examples of optical fiber amplifier to amplify optical signal. To design optical amplifier gain and NF are most significant points. Gain and NF are more significant points. Gain and NF have very strong impact on EDFA configurations. This paper focused on four important sections. First section is EDFA have enabled to use WDM, DWDM Technique, which uses denser channel spacing in order to achieve higher bit rates. The second section is based on the theoretical background of EDFA analysis and the parameters used for amplification related to spontaneous and stimulated emission. The third section is configuration of EDFA from the single pass to the quadruple pass. The fourth section is the different methods used for gain flattening of EDFAs depends on a large number of device parameters such as erbium ion concentration, amplifier length, pump power and core radious.
Dipika Pradhan : is a Assistant professor at Electronics and Telecommunication Department, RSSOER, JSPM, pune. Pursuing PHD in SVNIT, Surat in Electronics engineering Department. She is specialized in Electronics and communication engineering. She published some of the research article in optics and sensor networks.
V. Mishra : is a Associate Professor at Electronics Engineering Department, SVNIT, Surat.He is Specialized in optoelectronic devices, Optical sensor Networks and grating.
The use of OFCS generally allows for the transmission of large amounts of data at high speeds for long distance transmission. A detailed investigation of EDFA was given in three principal levels; first is the EDFA with WDM and DWDM technique in order to achieve higher bit rates. Second level is the Theoretical analysis of EDFA, where it is necessary to understand the physical meaning behind the amplification. The third level is the presentation of various configurations and their performance parameters related to different structures. These parameters need to be controlled to get higher gain and lowest NF.By increasing the total pump power, the transmission distance can be increased. On the other hand increasing the total injected pump power increases the non-linear effects of the transmission fiber, which degrades the system performance. Finally researches are expected to focus on reducing the noise figure at high pump powers.
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