Efficient M-QAM Digital Radio over Fiber System for Vehicular ad-hoc Network

In recent researches, it is estimated that Radio over Fiber technology is superior to other wireless technology system like Wi-Fi, WiMAX etc. as it is a consolidated broadband network which supports both optical and wireless technologies. Recent advances in wireless communication standards such as 802.11p, Wi-Fi, WiMAX, Microwave, Bluetooth etc. are playing vital role in establishing vehicle to vehicle communication to ensure road safety and traffic control. But these conventional technologies are failed to provide higher data rate. In this paper, a digital radio over fiber based VANET system is proposed in which several radio base stations communicate with a control system over DRoF connections. To improve the data rate in vehicle to vehicle communication, high order QAM signals is used for digital RoF architecture. The performance of both analog and digital RoF system for VANET is measured in presence of high order QAM signals in consideration of ADC resolution, SNR, BER. The required channel bandwidth is calculated for different level of QAM signal. The result shows, DRoF can provide better data rate and noise free channel for higher order QAM signal which is eventually a great outcome for the VANET.