Performance Analysis of Single Side Band Orthogonal Frequency Division Multiplexing in Radio over Fiber System with Direct and External Modulation Schemes

Abstract

Radio over fiber is a technology in which the light signals at the central station are modulated by a radio frequency signal, and by using the optical fiber it is transmitted to base stations. The data stream being sent is separated into subcarrier frequencies by the technique of orthogonal frequency division multiplexing. The orthogonality between the sub-carriers is provided by FFT modulation, which avoids the demodulators from accepting other frequencies. It is possible to transmit high-data rate signals over short and long distance by implementing orthogonal frequency division multiplexing with radio over fiber system along with the optical fiber. This enhances the system with more coverage area, and without increasing the cost of the system it provides the flexibility. The proposed work is to investigate the performance analysis of single side band orthogonal frequency division multiplexing in radio over fiber system with external and direct modulations using spectral analysers and constellation visualizers. The Mach-Zender modulator is proposed for external modulation, the vertical cavity surface emitting laser is used in direct modulation. The simulations were carried out by using Optisystem Software version 15.0 with global parameters for both intensity modulation schemes.

A Performance Analysis of Index Modulation in MIMO System

“…Similarly in [3] performance comparison of classical -MIMO and MIMO-OFDM has been done on the basis of bit error rate in a Rayleigh fading environment. In [5], localized and interleaved grouping has been used to get the achievable rates. This paper shows the effect of different modulation methods on the achievable rates for both OFDM and OFDM-IM.…”

“…Orthogonal Frequency Division Multiplexing effectively combats the problem created by frequency selectivity of wireless channel such as Intersymbol Interference and is similar to Frequency Division Multiplexing. It has three transmission principles namely Multirate, Multi symbol and Multicarrier [1][2][3][4][5]. Data is distributed over large number of carriers spacing them apart by a specified frequency.…”