1. Wireless traffic service platform for combined vehicle-to-vehicle and vehicle-to-infrastructure communications Authors : T. Sukuvaara and P. Nurmi IEEE Wireless Communications, Vol 16, pp. 54 - 61, December 2009 Speaker : 蔡明信

2.  Introduction  Related work  Platform and services  System description  Technical requirements  Available wireless technologies  Performance analysis and discussion  Conclusions outline

3.  The vehicle-to-vehicle (V2V) communication platform is currently a popular research topic  Traffic safety enhancement is the driving factor in many approaches,sensor data from vehicles and roadside units is used for providing accident and/or weather warnings to roadside units and vehicles. Introduction

4.  The capability for continuous communication is an important goal.  In the carlink project the aim was to build more comprehensive solution for vehicle-to-infrastructure (V2I) and V2V communication purposes.  Employed hybrid communication of general packet radio service (GPRS) and wireless networking. Introduction

5.  Wireless networking stands for the ultimate communication platform, while GPRS’s primary purpose is to provide an alternate communication solution.  The simulations, pilot testing, and analysis evaluate the basic communication efficiency of the platform. Introduction

6.  In the United States the Department of Transportation is coordinating the Vehicle Infrastructure Integration (VII) program.  The European (Cooperative Vehicle Infrastructure Systems)CVIS project generates an open standards- based communication. Related work

7.  The main advantages of carlink are the open platform solution, the flexibility and scalability of the platform into different types of services and capacity communication requirements, and operation reliability based on dual radio communications. Related work

8.  The Carlink platform is designed to provide an infrastructure to a wide community of commercial and governmental traffic and safety services. Platform and services

9. The wireless traffic service platform is divided into three parts: 1.Traffic service central unit (TSCU) 2.Traffic service base stations (TSBSs) 3.Mobile end users (MEUs) Platform and services

10. Carlink services.

11. Operational model of local RWS and incident warning service.

12. Schematic of the road weather model.

13.  The TSCU is on the top with connections to the underlying service cores, it also stores all data gathered from the platform and forwards the appropriate data to services.  Road weather service(RWS) core includes a weather forecast model System description

14.  The parameters gathered from the vehicle are the temperature, car throwing indicator, car sudden braking indicator, airbag blast notification  The WLAN/WiMAX and GPRS interfaces are used for communication with the TSBSs and TSCU.

15. Carlink platform structure

16.  The traffic speed (up to 100 km/h in our scenario) generates an extremely challenging element  Ad-hoc networking with handoff and seamless continuation of communication are important issues required in the final operative system. Technical requirements

17.  The most popular solution for wireless communication is the Wi-Fi system, which is based on the IEEE 802.11 standard family.  IEEE 802.11p represents the ultimate future solution Technical requirements

18.  wireless ad hoc communication between vehicles  ensure that the most crucial data will also be exchanged in the platform without any delay when there are no TSBSs nearby. Technical requirements

19. WLAN :  Wi-Fi  WiMAX Available wireless technologies

20. Two main simulation : 1.One-way traffic scenario 2.Bidirectional traffic scenario PERFORMANCE ANALYSIS AND DISCUSSION

21. Conditions :  four or eight vehicles are traveling at 100 km/h speed  The distances between consecutive vehicles were fixed to 100 m PERFORMANCE ANALYSIS AND DISCUSSION

22. Main results of the simulations

23.  Presented the carlink concept of a hybrid wireless traffic service platform between cars  Showcases a true bidirectional communication entity  Analyzed and forecast information about road weather conditions and immediate incident warnings. Conclusions

24.  Decrease accidents and lives lost in traffic.  The ultimate goal was to create an intelligent communication platform. Conclusions