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-The use of Vehicle-to-Vehicle (V2V) and Vehicleto-Infrastructure (V2I) communication will be an integral part on Intelligent Transportation System (ITS), and work on ITS has been growing substantially in recent years. A recent standard for V2V communication in the 5.2GHz band has been developed. Characterization of the channel in this frequency band in the ITS environment is of current interest to understand propagation behavior. More significantly for reliable communication is the presence of channel dispersion due to multipath propagation, also environment-dependent. It is important to note that the Doppler spectrum for vehicular environments is only valid for a short period of time. In this paper, to find effect of Doppler shift, we showed the simulation scenarios. And some channel models were simulated. As a results of, we confirmed an effect of Doppler shift in the ITS environments.Index Terms -Doppler shift, Channel Model, ITS. I . IntroductionThe use of Vehicle-to-Vehicle (V2V) and Vehicle-toInfrastructure (V2I) communication will be an integral part on Intelligent Transportation System (ITS) [1], and work on ITS has been growing substantially in recent years. In particular, different applications will emerge enabled by the exchange of information between cars. The information flowing between vehicles will likely be multimedia: data, images, video, and voice. The main ones concern the enhancement of road safety and the reduction of the traffic impact on the environment. These networks are called Vehicular Ad-Hoc Networks (VANETs) [2]. In order to transmit information reliably on rapidly changing vehicular channels one has to rely on a robust physical layer. Finding an accurate channel model for VANETs is still a research issue. Indeed, it has been shown in several papers that vehicular wireless channels exhibits specific characteristics that makes them quite different from the very well characterized mobile telephony channels [3],[4], [5]. A recent standard for V2V communication in the 5.2GHz band has been developed [6]. Characterization of the channel in this frequency band in the V2V environment is of current interest to understand propagation behavior. The strength of the received signal can change significantly depending on the absorbing, diffracting, and scattering effects from the surrounding environment. More significantly for reliable communication is the presence of channel dispersion due to multipath propagation, also environment-dependent [7], [8]. A V2V system may require from 2-54Mbps for distance of 15 -1000m at maximum speeds of 200km/h. A 10MHz bandwidth and higher order modulation can be used to achieve the required data rates. II . Wireless Channel ParametersThe simulation scenarios are Fig. 2 to find effect of Doppler shift.

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The cell sectorization techniques are widely used in cellular systems to reduce co-channel interference by means of directional antennas. Cell sectorization and improvement of the chip energy/others interference ratio (E c /I o ) are technologies to offer good quality of services (QoSs) and coverage for new and sophisticated power control to achieve high capacity. In this study, we analyze and compare performances of two trisector cell architectures with different antenna beam-widths-a wide-beam trisector cell (WBTC) and a narrow-beam trisector cell (NBTC)-in order to achieve effective cell sectoring in CDMA and cellular mobile communication systems. These architectures are outcomes of cell sectorization, which is widely employed in cellular systems for reducing co-channel interference. We verify the effectiveness and validity of the NBTC architecture by theoretically comparing it with the WBTC architecture (using parameters such as softer handoff and interference ratio). Further, we analyze results of a simulation of the WBTC and NBTC and of a field measurement performed in Namwon city in Korea. From the analysis, we find that the NBTC architecture is more efficient than the WBTC architecture in minimizing interference from adjacent BSs and increasing cell coverage while maintaining a good QoS.