VANET plays a key role in an Intelligence transportation system. To avoid accidents and inform the traffic information, VANETs infrastructure plays an important role. This paper concentrate on V2I communication, that is information exchange among the vehicles, this can be done with a Roadside Unit (RSU). The main function of RSU is to act as a data repository for information exchange among the vehicles to and from like traveller information, traffic information, accidents zones, etc. RSU is a standalone device that communicates with vehicles as well as with Communication networks. Deployment of RSUs was cost-effective, once we install, we cannot mobile the RSU Equipment, so the right way of placing RSU is very important. This paper focuses on and proposed a cost-effective RSU deployment strategy in the VANETs environment, the proposed strategy is based on principles of adaptive beamforming method, by applying these principles, we select an effective emplacement of RSU in different vehicular environment topology.