Delay and broadcast reception rates of highway safety applications in vehicular ad hoc networks

IEEE- and ASTM-adopted dedicated short range communications (DSRC) standard towards 802.11p is a key enabling technology for the next generation of vehicular safety communication. Broadcasting of safety messages is one of the fundamental services in DSRC. In this paper, requirements and channel design of vehicular ad hoc networks for safety applications are addressed. Performance of vehicle-to-vehicle (v2v) safety related services in DSRC system on highway is investigated analytically and by simulation. Under some reasonable assumptions, analysis is conducted to characterize IEEE 802.11a-based channel for safety message broadcast under harsh DSRC highway environment with high vehicle mobility, dynamic self-organized network topology, and adverse multi-path fading channel. Based on solutions to the proposed analytic model, transmission delay and packet reception rates are derived. The proposed analytic model accounts for impact of priority access, message arrival interval, hidden terminal problem, fading transmission channel, and highly mobile vehicles on performance indices for DSRC safety related communication. From the obtained numerical results under various offered traffic and network parameters, new observations and effective enhancement suggestions are given.