Bit Error Rate Mitigation in VANETs Using FFH-OFDM Pre-coding Approach

VANET (Vehicular Ad-hoc Network) is based on IEEE 802.11p standard. It is designed for Vehicle to Vehicle (V2V) and Vehicle to Infrastructure (V2I) communication systems purposely for safety, infotainment and traffic management. Nevertheless, due to mobility of communicating nodes, V2V and V2I networks are susceptible to higher errors rates. This is because of Doppler effects on signals caused by relative velocities between communicating vehicles (V2V) or between vehicles and fixed receivers along the pathways (V2I). This paper investigates and proposes the use of fast frequency hopping orthogonal frequency division multiplexing (FFH-OFDM) pre-coding approach to mitigate higher BER associated with Doppler spread in VANETs. FFH-OFDM communication system and Doppler spread channel are modeled and simulated using MATLAB MEX functions and Simulink subject to VANETs standard parameters. BER curves are used as performance metrics for comparison between conventional OFDM and FFH-OFDM models. Under same Doppler spread, simulation results depicted better error performance for FFH-OFDM Pre-coding approach compared to conventional OFDM.