Rainer Steffen

A system for QOS-enabled MPEG-4 video transmission over Bluetooth for mobile applications

Streaming media distribution is a rapidly growing application. The increasing number of broadband Internet subscribers, the growing market for smart in-home networks and the upcoming broadband mobile phone networks encourage this trend. In addition, the number of multimedia enabled mobile devices such as PDAs, smart embedded devices and notebooks is rapidly growing. MPEG-4 is one of the favorite video coding schemes, and Bluetooth is a preferred wireless technology for small and smart devices because of its small size, low power consumption and cost efficiency. In this paper we present a complete quality of service (QoS) enabled system that integrates a MPEG-4 codec and a Bluetooth device for mobile video applications.

Quality of service MAC protocol for shared media in-house networks

We present a method to enable real-time communication with guaranteed quality of service over shared media in-house networks. This method is a flexible approach for different kinds of applications with varying requirements on data rate and delay, like live multimedia communication, home-control and automation or WWW-services. It is based on an extension of the standard medium access control by a deterministic token-passing protocol that can be applied to different network technologies, like shared media Ethernet, HomePNA or Powerline. We demonstrate how a mathematical pre-runtime analysis of the timing behavior can be performed, so that quality of service and real-time behavior can be guaranteed even in worst case situations.