V2V Channel Performance on VANET Technology with OFDM and Moving Scatterer’s Influence

The channel modeling in VANET technology has been developed by involving various factors, i.e., propagation, scatterer, traffic density, and their environments. One of them is the V2V channel that involves moving scatterer. This modeling has not been yet incorporated in with OFDM. Hence the performance is still unknown. This paper used a V2V channel influenced by moving scatterer and combined with OFDM. Two vehicles were modeled as transmitter and receiver, while 8 scatterers moved at constant speed. Model's gain channel was convoluted with OFDM and modulated with QPSK. Fast moving vehicle yielded Doppler effects which impacted Coherence Time and number of symbols in one OFDM frame. Higher Doppler effects as a result of faster vehicle, lowered Coherence Time made the number of correlated symbols in one frame was decreasing. Simulation showed at speed of 10 - 20 m/s, the decreasing of Coherence Time and number of correlated symbols was the most significant and noticeable. As the Coherence Time decreased up to 50% whilst some correlated symbols decreased up to 75%. The number of moving scatterer used greatly affected SNR value where the increase in the number of moving scatterer doubled from 4 to 8 resulted in a decrease in SNR value up to 6 dB at the speed of 40 m/s.