Placement of Road Side Units for floating car data collection in highway scenario

Floating car data (FCD) has been used to collect traffic state information from a set of individual vehicles. Vehicles are equipped with On Board Units (OBU) that collect different measurements and the vehicle position and transmit the data to a remote control center. In current implementations of FCD systems, vehicle fleets use cellular connections for data transmission. In this paper we consider an IEEE 802.11p-based Road Side Unit (RSU) infrastructure for FCD collection. Installing RSUs in order to acquire perfect coverage may prove to be a costly solution, while gaps between the coverage areas will force data buffering at OBUs. This might be a viable solution for delay-tolerant, but not for safety-critical applications that require high data delivery ratio. The goal of this paper is to study the trade-offs between the size of the gaps between RSUs and other system parameters such as data delivery ratio, data collection update interval and size of measured data. We have proposed some heuristics that can be used while deciding on the distance between neighboring RSUs.