الفهرس 
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Abstract
This thesis focuses on improving the traffic system by using an imaging receiver instead of photodiode as a single receiver. The use of visible light communication (VLC) with different modulation techniques is considered one of the most important technical issues. The On-OFF Keying (OOK), L-Pulse Position Modulation (L-PPM), and Inverse L-Pulse Position Modulation (I-L-PPM) are investigated. In this work, a road with three lanes is considered, the received information changes according to many factors such as the communication distance and the number of pixels for the imaging receiver. A simple traffic model has been proposed and analyzed in order to optimize various important design characteristics such as, signal to noise ratio (SNR), required power, bit error rate (BER), and modulation technique. The simulation results show that,an imaging receiver with 64×64 pixels is more suitable practically for a communication distance in the range 10 - 50 m between the traffic light and the vehicle. Also, the results indicate that, in the three lanes, the received information (RI) is increased as the number of pixels increases, but,it is degraded in second and third lanes. The replacement of a photodiode by an imaging receiver leads to an improved SNR and a reduction of both the required transmitter power and BER. 16-PPM requires 10 dB less power than 16-I-PPM requires, but in the expense of bandwidth used.After that, a hybrid communication system utilizing VLC and radio frequency (RF) is proposed for position-based services. The VLC/RF system combines the benefits of both systems and offers long distance transmission which is an important concern in intelligent transportation system (ITS)and in order to improve the link reliability in infrastructure to vehicle (I2V) communications. This means that the probability of having a communication link between the transmitter and receiver is maintained without interruption. Then the performance is finally evaluated. The simulation results show a considerable increase in the received information using the proposed hybrid VLC/RF system compared with a VLC system.