International Journal of Research in Engineering, Technology and Science, Volume VII, Special Issue, Feb 2017 www.ijrets.com, editor@ijrets.com, ISSN 2454-1915 Aruna Rani, Manjit Singh Bhamrah, Sanjeev Dewra, Kulwinder Singh 1 SIMULATIVE ANALYSIS OF OPTICAL OFDM SYSTEM USING EDFA-RAMAN HYBRID OPTICAL AMPLIFIER Aruna Rani a* , Manjit Singh Bhamrah b , Sanjeev Dewra c , Kulwinder Singh d a,c Shaheed Bhagat Singh State Technical Campus, Ferozepur b,d Punjabi University, Patiala, Punjab, India arunarani70@gmail.com, manjitsingh_manjit@rediffmail.com, sanjeev_dewra@yahoo.com. ksmalhi@rediffmail.com ABSTRACT: This paper demonstrates the architecture of direct detection optical Orthogonal frequency division multiplexing OFDM systems and carries out performance analysis based on EDFA- RAMAN hybrid optical amplifier in terms of bit error rate and Q-factor at different input powers. It is found that the signal can be transmitted with acceptable BER and Q-factor at low signal input power of -0.7 dBm upto 600 km transmission distance using EDFA-RAMAN hybrid optical amplifier. The signal can be transmitted successfully upto 512 km without hybrid amplifier at 10 Gbps bit rate. Keywords: OFDM, BER, QAM, Q-factor, EDFA-RAMAN. [1] INTRODUCTION There is a growing demand for high speed, spectrally efficient and reliable communication. Providing high quality services in a optical environment has several challenges. Optical Orthogonal Frequency Division Multiplexing is considered as a promising technology to satisfy the increased demand for bandwidth in broadband services [1]. Orthogonal Frequency Division Multiplexing (OFDM) essentially identical to Coded OFDM (COFDM) is a digital multi-carrier modulation scheme, which uses a large number of closely spaced orthogonal sub-carriers [2]. OFDM splits the total transmission bandwidth into a number of orthogonal and non-overlapping subcarriers and transmit the collection of bits called symbols in parallel using these subcarriers. The main advantage of the OFDM is its ability to overcome channel dispersion. Also, OFDM has the ability to transmit information with high data rates which has made it popular [3]. OFDM has been used in many different applications in the RF domain such as digital audio broadcasting (DAB), digital video broadcasting (DVB), and Wireless Local Area Networking (WLAN) [4-5]. Hybrid amplification is an effective technique for optical regeneration; it has a low NF as compared to individual fiber amplifiers. The gain profile is also much flatter, so they are able to accommodate more channels [6]. Nir Sheffi and Dan Sadot [7] proposed an Optical orthogonal frequency division multiplexing with a novel direct modulation and coherent detection system at