Location referencing systems for dynamic route guidance applications

Dynamic route guidance applications can be distinguished into systems supported by RDS/TMC, short range (beacon), or cellular radio systems (e.g., SOCRATES). The quality of all three classes depends on accurate information (in time and location) about the traffic situation. This information is exchanged between the mobile part (e.g., the cars) and traffic center. The time relation can be covered by independent realtime clocks in both parts of the system. But for the location relation a referencing system is needed. Today an agreed location referencing system - as part of the ALERT/C protocol for traffic messages - exists in Europe for RDS/TMC applications. The Standard Location Reference Number (SLRN), a solution for a common location referencing system is presented. It will be implemented in the SOCRATES (cellular radio) pilots.