2 research outputs found
Towards understanding the performance of IEEE 802.11 MAC in heterogeneous traffic conditions
Motivated by the need to study the performance of vehicular communication
protocols as applicable to heterogeneous traffic conditions, we study the
performance of IEEE 802.11p medium access protocol under such a traffic setup.
We consider a setup comprising connected vehicles and human-driven Motorised
Two Wheelers (MTWs), where the connected vehicles are required to move as
platoon with a desired constant headway despite interruptions from the two
wheelers. We invoke specific mobility models for the movement of the
vehicles--car following models for connected vehicle platoons and
gap-acceptance model to capture the movement of the MTWs--and use them to
configure (i) the traffic setup and (ii) the rate at which data packets related
to safety-critical messages need to be transmitted. A control-theoretic
analysis of the car-following models yields a bound on the admissible
communication delay to ensure non-oscillatory convergence of the platoon
headway. We then use suitable Markov chain models to derive the distribution of
the MAC access delay experienced by packets pertaining to safety-critical
events as well as routine safety messages. The distribution along with the
bound on the admissible delay enables us to derive the reliability of the
802.11p MAC protocol in terms of traffic and EDCA parameters. Our study
highlights the need for redesign of MAC protocols for vehicular communications
for safety-critical applications in heterogeneous conditions.Comment: 15 page