Research Article
Adaptive Contention Window Design to Minimize Synchronous Collisions in 802.11p Networks
@INPROCEEDINGS{10.1007/978-3-319-51207-5_4, author={Syed Shah and Ejaz Ahmed and Iftikhar Ahmad and Rafidah Noor}, title={Adaptive Contention Window Design to Minimize Synchronous Collisions in 802.11p Networks}, proceedings={Future Intelligent Vehicular Technologies. First International Conference, Future 5V 2016, Porto, Portugal, September 15, 2016, Revised Selected Papers}, proceedings_a={FUTURE 5V}, year={2017}, month={1}, keywords={VANET Synchronous collisions ITS 802.11p Congestion control Media access control Contention window Adaptive contention window}, doi={10.1007/978-3-319-51207-5_4} }- Syed Shah
Ejaz Ahmed
Iftikhar Ahmad
Rafidah Noor
Year: 2017
Adaptive Contention Window Design to Minimize Synchronous Collisions in 802.11p Networks
FUTURE 5V
Springer
DOI: 10.1007/978-3-319-51207-5_4
Abstract
The vehicular ad hoc network (VANET) capable of wireless communication will enhance traffic safety and efficiency. The IEEE 802.11p standards for wireless communication in the US and Europe use a single shared channel for the periodic broadcast of safety messages. Coupled with the short contention window and inflexibility in window size adaptation, the synchronous collisions of periodic messages are inevitable in a large scale intelligent transportation system (ITS). To this end, we propose an adaptive contention window design to reduce synchronous collisions of periodic messages. The proposed design replaces the aggressive window selection behaviour in the post transmit phase of IEEE 802.11p with a weighted window selection approach after a successful transmission. The design relies on the local channel state information to vary contention window size. Moreover, in high density networks, the design gives prioritized channel access to vehicles experiencing dropped beacons. The proposed design can be readily incorporated into the IEEE 802.11p standard. The discrete-event simulations show that synchronous collisions can be reduced significantly to achieve higher message reception rates as compared to the IEEE 802.11p standard.
