Performance improvements of HCCA scheduling in V2R environments

Abstract

SummaryThis paper addresses the issue of real‐time data transmission in vehicles to roadside environment by the hybrid coordination function controlled channel access (HCCA) scheme with Institute of Electrical and Electronics Engineers 802.11p protocol. The HCCA is one of the medium access protocols specified in 802.11p standard, which uses a polling scheme similar to the point coordination function to provide a reliable QoS. In this paper, we improve the HCCA polling scheme and design a new data transmission scheduling method. We also prepared a mathematical model to systematically evaluate the performance of the HCCA in terms of average delay. Moreover, we analyze the factors that could impact the average delay, throughput, and packet loss rate as well. The simulation results are compared with the original scheme specified in the standard. The simulation results demonstrate that the proposed delay model could estimate the average delay of the HCCA with a high precision, whereas the proposal of the enhancement of the HCCA has lower delay, lower loss rate, and higher throughput than the one specified in the standard. Copyright © 2013 John Wiley & Sons, Ltd.