Reliability and Safety/Integrity Analysis for Vehicle-to-Vehicle Wireless Communication 2011-01-1045

Vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications are gaining increasing importance in automotive research and engineering domains. The novel communication scheme is targeted to improve driver safety (e.g., forward collision warnings) and comfort (e.g., routing to avoid congestion, automatic toll collection, etc.). Features exploiting these communication schemes are still in the early stages of research and development. However, growing attention to system wide infrastructure - in terms of OEM collaboration on interface standardization, protocol standardization, and government supported road/wireless infrastructure - will lead to popularity of such features in the future. This paper focuses on evaluating reliability and safety/integrity of data communicated over the wireless channels for early design verification. Analysis of a design can be done based on formal models, simulation, emulation, and testing. The first two are preferred choices over the latter two for early verification, as both formal models and simulation provide rapid verification with high repeatability, fast turnaround time, high control, and high flexibility. Though formal models and simulation may provide lower realism, they help in narrowing down alternatives by discarding outliers. In this paper, we focus on three analysis techniques for early verification/analysis of wireless channels: formal state transition modeling, simulation of the protocol, and hazard and risk assessment. The first two techniques have been considered in several earlier works - in particular, the paper focuses on Markov Chain modeling of the protocol behavior, and simulation of the protocol in ns2. We use both techniques for analyzing a representative vehicle-to-vehicle communication system and present a comparison of the techniques from the outcome of the analysis. The third technique, hazard and risk assessment (H&RA) approach based on ISO/DIS 26262, has attracted a lot of attention for automotive safety/integrity analysis - however, to the best of our knowledge, the approach has not been widely used with perspective to V2V communication. By applying the H&RA approach to wireless systems, hazards are identified, controls and mitigations are proposed, and safety goals are determined. The controls and mitigations as well as the safety goals will provide requirements on the reliability of the wireless channels and on the communication network architecture.