Towards Standardized Channel Models for Short-range Vehicular Communications. David G. Michelson*, David Matolak**, John Wang*, and Alexander Corbett* *University of British Columbia, Dept. of Electrical and Computer Engineering, Vancouver, BC, Canada **Ohio University, School of Electrical Engineering and Computer Science Athens, OH, USA Why are standardized channel models important? Channel models capture our knowledge and understanding of the manner in which propagation impairments manifest themselves in a particular environment in a form useful in design and simulation. Standardized channel models permit fair comparison of alternative PHY, MAC and network layer schemes across a representative range of channel conditions. How are standardized channel models developed? A channel modeling committee works with PHY. MAC and network developers to determine: -the channel impairments to which the proposed PHY, MAC and network layer schemes are likely sensitive, and, -the range of environments and scenarios within which the proposed systems will likely be delpoyed The channel modelling committee reviews the published literature and identifies relevant works. -If the published works are inadequate, the committee may put out a call for submissions based upon work either recently completed or in progress The committee proposes and evaluates alternative forms for the standardized channel models based upon a tradeoff between model accuracy, computation efficiency and the cost and availability of increasing levels of detail concerning the environment. The committee recommends parameters for the standardized channel models based upon results presented in published works and recent submissions. The committee may recommend test suites that permit implementations of the standardized channel models to be validated. The committee releases a channel modelling report that summarizes the results of their work in order to provide guidance to system designers and simulation tool developers. Vehicle Unit Roadside Unit 1 What are some common VANET (Vehicular Ad hoc NETwork) simulation tools? NS-2 GloMoSim OMNeT++ JiST/SWANS Are standardized channel models available for short- range vehicular networks? No. As a result, -simulation tool developers must use their own best judgement when selecting or implementing channel models -there are significant differences between the channel models incorporated into today’s VANET simulation tools and -fair comparison between results obtained using different simulation tools is difficult. How is the IEEE VT-S Propagation Committee proceeding to develop standardized channel models for short-range vehicular networks? The Short-Range Vehicular Channel Modelling Initiative will be launched at IEEE VTC Fall The VANET community will be engaged at other events such as the 2011 NSERC DIVA Workshop and the IEEE ICC 2012 Workskop on Intelligent Vehicular Networking. VANET simulation tool developers will be engaged directly and their feedback sought. The results will be released at a special session or workshop at IEEE VTC Fall How will a given simulation tool’s compliance be verified? A test suite will be released that will allow a given simulator’s compliance with the channel modelling standard to be verified. A compliant simulation tool will be allowed to display a logo that shows that it is compliant with the IEEE VT-S standardized short-range vehicular channel model. Will compliance require that the developer exclude alternative channel models models? No. Compliant simulators will be encouraged to implement alternative channel models but must provide a simple method for invoking the IEEE VT-S standardized channel models. TraNS OPNET Modeler QualNet J-Sim