Coherent Multiplexing Technique for Data Transmission without ICI

In order to achieve data transmission without InterCarrier Interference (ICI) the Constant Envelop Minimum Shift Keying Orthogonal Frequency Division Multiplexing (CE-MSK-OFDM) technique is proposed in this paper. The amplitude doesn’t vary during modulation in the carrier wave so it maintains Peak to Average Power Ratio(PAPR) and using Minimum Shift Keying can produce Constant Envelop(CE) due to its smooth phase transitions. The conventional Orthogonal Frequency Division Multiplexing (OFDM) system capable of counteracting fiber nonlinearity, excellent resistance to chromatic dispersion and reduce PAPR. Normally, OFDM uses Quadrature Phase Shift Keying (QPSK) modulation technique it decrease PAPR but when there is a abrupt amplitude variations the higher order terms of phase modulated signal, then the data will spread over multiple subcarrier results in inducing a large ICI. In QPSK, the modulated signal cannot be of continuous phase and it provides slow roll off side lobe spectrum which decays asymptotically. The concept proposed here attenuate the downside of Constant Envelop Quadrature Phase Shift Keying Orthogonal Frequency Division Multiplexing (CE-QPSK-OFDM).