Cross layer consideration for improved reliability of vehicular safety messaging

This paper presents a theoretical foundation for a new collision correcting medium access control (MAC) and physical (PHY) cross layer design (CLD) for safety messages in dedicated short range communications (DSRC). The concept relies on repetition messaging and the fact that DSRC safety messages are relatively short in length. Hence our design requires a cache of previously received packets, and pre informed packet repetitions. An example scenario is provided with a step by step description of how our proposed system will behave. Unified modeling language (UML) use case diagram is used to help describe functionality of the CLD. The operation of the collision correcting (CC) channel estimator (CE) and equalizer (EQ) is explained. Simulation results show reception reliability and PER performance is improved when our CLD is used as opposed to standard safety message broadcasting, especially in high repetition scenarios.