Synchronized interactive services for mobile devices over IPDC/DVB-H and UMTS

DVB-H (Digital Video Broadcasting - Handheld) is a technical specification for bringing broadcast services to handheld receivers. IP Datacast integrates DVB-H in a hybrid network structure consisting of both a mobile communications network such as GPRS or UMTS and an additional DVB-H downstream. This paper introduces two different approaches for providing interactive services to DVB-H terminals. It is assumed that the terminals dispose of a MIDP compliant runtime environment. The Mobile Information Device Profile (MIDP) is a J2ME profile for the use of Java on embedded devices such as mobile phones and PDAs. It is shown how these services can be synchronized with the multimedia data that is broadcasted over the DVB-H channel. A first approach will only use the DVB-H broadcast channel as bearer of both the audiovisual data and the interactivity-related data. The second approach combines the broadcast path with a bidirectional unicast channel in order to implement the interactive services.