Overview of network topologies for V2X communications

Modern Intelligent Transport Systems are based on communications between different devices (fixed and/or mobile). As many communication solutions have appeared, and the bandwidth used is similar, the more crowded communications channels have become. For non-critical applications there are several convenient (common) solutions that must be considered, such as Wi-Fi, Bluetooth or ZigBee, that can ensure the proper connection time and data rate (depending on the requirements). From these, Wi-Fi solution using 2.4 GHz frequency band seems to be the most unsuitable one, as data rates vary in large parameters depending on the existence of other communications. Therefore, in this article, we'll present the solutions that may be adopted using Bluetooth and ZigBee communications. For this, we'll present typical network topologies (chapter II), define specific conditions for ZigBee and Bluetooth networks (chapters III and IV) and test different configurations of ZigBee networks in order to determine the most suitable one for vehicle-to-vehicle or vehicle-to-infrastructure communications.