5.9Ghz car-to-car measurements

To get a feeling for how well car-to-car communication actually works on the 5.9Ghz ITS band we went on a test-drive last week. We equipped two vehicles and ran through a number of interesting scenarios such as:

• Travelling in different directions on the highway (~240 km/h relative speed)
• Driving in urban areas with multi-storey buildings
• Rural areas, especially at hilly locations/crests
• Flat areas with clear line-of-sight.
• Driving in the same direction on the highway with large trucks between transmitter and receiver
  

Although we had been expecting it, the correlation between line-of-sight and packet-reception-rate (PRR) was surprisingly clear. The picture below shows PRR as a function of location in the urban scenario. The yellow marker indicates where the transmitting vehicle was parked as we circled the block with the receiver. Green bars show locations with almost no packet-drops while just around the corner all packets are dropped. Ways of handling situations with such poor reception is the current focus of my research, the results from these preliminary test drives really emphasize the need for solutions to communication "black spots".



We are using the MatLab Google Earth toolbox to create these visualizations, highly recommended!

CVIS + CERES collaboration report

For the past few years the Cooperative Vehicle-Infrastructure Systems (CVIS) project has been working to enable vehicles to talk to each other and to infrastructure in order to enable safer, greener and more fun transportation. In parallel our lab at Halmstad University has been working towards the same goals within the Vehicle Alert System (VAS) project. As CVIS nears its end we summarized our work together in a report which is now available from the CVIS website.

"Parallel activities bring CVIS results closer to deployment

We have received the final report on the collaboration activities between CERES/VAS and CVIS, one of the 14 projects we are cooperating (or currently discussing cooperation) with: CVIS grants use of CVIS Reference Execution Platform, Core Software and CVIS Software Developers’ Kit in exchange for external testing and evaluation (see Third Party Cooperation section of this website).

In March 2007, an agreement was made for interchange of experiences between CVIS and the Centre for Research on Embedded Systems (CERES) at Halmstad University in Sweden. The majority of the work relating to this collaboration has been conducted within the CERES project Vehicle Alert System (VAS), aiming to use vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications to provide different types of warning messages. The main focus of the VAS project is on communication and in particular the lower layers of the communication stack are investigated."