Department Publications

Due to high costs at initiation, alternative communication strategies to dedicated short range communication (DSRC) have been looked at to facilitate quick deployment of intelligent transportation services. Wi-Fi Direct (WD), has come across as a candidate, and this paper focuses on the drawback of large transmission delays in WD. To this end, it studies the performance gains of using a broadcast mechanism on the downlink between the group owner (GO) and the clients of a WD group, instead of the currently used peer-to-peer method. Gains in terms of average total delay and the average energy consumption of the GO are presented using a theoretical analysis as well as a simulation study using OMNeT++. It is also shown that the degradation in performance on the downlink due to not having retransmissions is within tolerable limits given that the size of the group is selected properly.

We present a simulation study of a cooperate car following application implemented by the Wireless Access for Vehicular Environ-ments (WAVE) protocol stack, which uses the MAC and Physical lay-ers defined by the IEEE 802.11 p protocol. This is a simple Intelligent