Dalibor Turina

Link layer analysis of the General Packet Radio Service for GSM

The General Packet Radio Service (GPRS) is one of the services being standardized by ETSI for GSM Phase 2+. This paper briefly presents the status of the GPRS standard giving special attention to the link control/medium access control (RLC/MAC) protocol layer. Subsequently, an analytical evaluation of the GPRS downlink performance is presented. Faced with the increased use of Internet services, the downlink performance is an important metric as users-especially mobile users-will use the Internet mainly for consuming information, i.e. produce downlink traffic load.

Mobile TV - The Concept Overview and Technology Enablers

Summary form only given. Bringing TV experience to the mobile users opens up a new era in the evolution of the mobile systems. Even if it started as a mere copying of the linear TV distribution of today, the mobile systems technologies that can provide feedback channels from every user enable new ways of enhancing the TV experience. So besides just watching TV via broadcast or on demand, a whole myriad of possibilities is enabled where the end-user can actively participate in the interactivity sessions with the content provider and indirectly with other viewers. Further, more sophisticated terminals enable pre-recording of the subscribed content to be consumed at the users convenience. Today, 3G wireless systems offer a superior streaming capabilities for TV distribution, either as unicast service (e.g. HSPA) or broadcast service (e.g. MBMS). Actually, the best utilization of the resources is provided with a combination of the unicast and broadcast services, where unicast part is used in areas with lower demand and for offering basically unlimited number of channels, while broadcast part is used as a capacity booster in areas where several users are interested in the same content. There are also alternative pure broadcast technologies like DVB-H, DMB, ISDB-T and MediaFLO that are gaining traction in different parts of the world but to provide interactivity they must be integrated with some cellular system. That makes the Mobile TV market segmented for the time being but the near future will show what model is capable of gaining the largest momentum thus creating mass market for Mobile TV.