• S.Alagu
• Dr.K.Bhoopathy Bagan

Free Space Optical (FSO) communication is an optical communication technology in which optical data transmitted wirelessly from one place to another. Some of its main advantages are high security, faster installation, license free spectrum. The performance of the FSO system is affected by the atmospheric conditions like haze, fog and snow. To reduce the effects of atmospheric disturbance Coherent Optical Orthogonal Frequency Division Multiplexing (CO-OFDM) with dual polarization, is proposed. A novel design for FSO communication system is considered. The proposed model is designed by hybridizing PDM and OFDM and its performance is analyzed under different atmospheric turbulences such as very clear weather, daily weather, fog and rain weather conditions. The proposed design exhibits an improved performance with SNR values of 55.64dB and 48.27dB at 3km in clear and cloudy skies respectively. The cardinality of the system is increased by utilizing dual polarization OFDM technique with 6dB penalty of SNR at 3km.PDM technique is used to boost the capacity and also enhances the spectral efficiency. OFDM modulation reduces the multipath fading occurred during the FSO transmission. The measured and simulated results confirm the benefits of the proposed design. The proposed system can also work as a reference for the FSO application even in bad atmospheric conditions.

Coherent Optical Orthogonal Frequency Division Multiplexing (CO-OFDM), Free Space Optics (FSO) and Polarization Division Multiplexing (PDM).

"Performance Analysis of Hybrid PDM-OFDM Technique for Free Space Optical Communication System under adverse weather conditions ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 6, page no.711-720, June-2019, Available :http://www.jetir.org/papers/JETIR1906247.pdf

"Performance Analysis of Hybrid PDM-OFDM Technique for Free Space Optical Communication System under adverse weather conditions ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 6, page no. pp711-720, June-2019, Available at : http://www.jetir.org/papers/JETIR1906247.pdf