DefinePK

Abstract

Orthogonal Frequency Division Multiplexing can be considered as a principle multiple carrier modulation formats and used in various types of applications such as wireless and optical communication. It is regarded as a perfect method which is used for high speed optical communication; furthermore it has high spectral efficiency and robustness to path losses. Nonetheless, it suffer from High Peak to Average Power Ratio which is considered as one of the main problem that is experienced by the optical orthogonal frequency division multiplexing system, which directly has an effect on the characteristics of the system. Notably when the Peak to Average Power Ratio increases, the nonlinear and linear impairments in optical fiber will be high. Chromatic dispersion, polarization mode dispersion as linear impairment and nonlinear characteristics include self-phase modulation, cross-phase modulation and four-wave mixing. This paper proposes an efficient cascade hybrid technique to reduce the PAPR by combining the nonlinear technique of modified sliding norm transformer (MSNT) and the clipping linear technique in the coherent optical OFDM (CO-OFDM) system. In effect, the proposed technique does not need to send side information to the receiver; in addition it doesn’t degrade in bit error rate and bandwidth. The simulation results reveal that the system performance has been significantly improved when using this proposed technique in comparison with other individual techniques of clipping and modified sliding norm transformer. As a result, it is found that PAPR reduction can be achieved to 5.1 dB from the original signal for error probability of 10-3. Further, the measured Quality factor enhanced in about 1.1dB and error vector magnitude in about 1 dB with optical fiber long up to660 km.