DESIGN AND SIMULATION OF EXTERNAL MODULATION TECHNIQUE BASED RADIO OVER FIBER (ROF) COMMUNICATION SYSTEM

AOptical fiber backhaul providing high speed interconnection to a large number of antenna base stations, so Radio over Fiber (RoF) is one of the next generation technologies in optical fiber communication systems that support efficient convergence of wireless and optical access network structure. Also, promising solution for increasing demand for larger transmission bandwidth with voice, data and multimedia service for fixed and mobile users. In (RoF), light is modulated by using a radio signal and sent over an optical fiber link to simplify wireless access. This project is focused on the investigation and performance analysis of externalmodulation, variations in Q-factor and BER with respect to fiber length at wavelength (1310) nm using (Optisystem 7.0) simulation software.Simulation results have been included to show the comparative performance evaluation of parameters like maximum Q-factor, minimum BER, eye height and threshold with respect to bit rate and fiber length for different modulation techniques. Simulation results show that the proposed system exhibits desired performance with external scheme. This paper also suggested optimal tradeoff between bit rate and fiber length for the particular system.