ANNUAL REPORT 2012

decentralized, self-organizing and aims at minimizing
interference between any transmitters, but it
does not necessarily maximize the PRP for the closest
neighboring nodes or provide scalable, fair and
predictable channel access for broadcast. In CVAN,
a decentralized, self-organizing, predictable and
scalable MAC algorithm capable of maintaining a
high PRP for the closest neighboring nodes also in
overloaded networks is under development.
Traffic-safety applications based on broadcast:
An efficient data dissemination strategy for trafficsafety
applications must ensure a high success rate
regarding the timely delivery of the emergency
message to all the vehicles within a safety zone.
Thus, we have developed an adaptive selective
broadcast algorithm which increments the transmission
power level of the sender each time it senses
that warning messages are not received. Compared
to regular selective broadcast algorithms and flooding,
our algorithm shows a clear improvement in
warning delivery ratio even when network connectivity
is low. A high-performance dissemination algorithm
proactively adapting transmission power to
network density is the next objective in CVAN.
Scientific Achievement and Activities
Halmstad actively participates in standardization
within ETSI TC ITS. The work on the MAC layer
resulted in ETSI initiating a specialist task force
(STF395) to evaluate time-slotted MAC approaches
for VANETs. Katrin Sjöberg from Halmstad was
elected the STF leader and received Euro 45 000:-
from the European Commission funding her research.
The project members organize a yearly workshop
on Wireless Vehicular Communications, which
apart from speakers from Lund and Halmstad also
features invited speakers funded by IEEE VTS. In
2012 it was Andreas Festag, NEC and the workshop
took place Nov. 30, 2012 in Halmstad,
www.hh.se/wwvc2012.
CERES Annual Report 2012
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