Reliable broadcasting using polling scheme based receiver for safety applications in vehicular networks

Vehicular wireless communication is the enabling technology of Intelligent Transport System (ITS). However, it is broadcast in nature and error-prone, as well as it has stringent safety constraints in short contacting time. Therefore, existing Medium Access Control (MAC) protocols for vehicular networks still have many technical issues related to transmission efficiency and reliability. Moreover, at the same time, robust one-hop communications and efficient multi-hop dissemination are required for different coexisting safety-related applications. In this paper, we propose a polling scheme triggered by receivers to make broadcasting more reliable and study how reliable broadcasting affects dissemination of safety-related information. In order to evaluate our proposed polling scheme, an analytical model specified for the IEEE 802.11p standard is presented and validated with consideration of prioritized traffic, probability of error transmission and multi-channel operation. Analytical analysis shows that our polling scheme enhances significantly success ratio of broadcast messages. Also, our reliable broadcasting protocol improves the performance of dissemination. Moreover, extensive simulation results demonstrate an improvement for both one-hop communication and multi-hop dissemination when the proposed polling scheme is implemented at the MAC layer.