Monthly Archives January 2010

Mobile data services are now available in cellular networks and their use will increase in the next few years. Providing high data rate is then a major issue for operators. As the propagation conditions are very variable in wireless mobile systems, a lot of attention has been paid to optimize the transmission protocols between mobile phones and the network (fast link adaptation, hybrid protocols that combine automatic repeat request and forward error correction). In a lot of cases, a given mobile phone may have poor transmission conditions though another phone close to that one has good conditions. Developping cooperation between terminals is then a natural idea to improve the overall performance. Cooperative transmissions has already received a lot of attention but mainly from a signal and digital communication point of view. Our research focuses on the definition and the optimisation of link layer cooperative protocols.

In a fist step, we studied automatic repeat request (ARQ) protocols on a block fading channel without cooperation. We developped a comprehensive analytical study based on a simple packet error mode (report TRITA – ICT – COS – 1001). We showed that the performance of ARQ and Hybrid ARQ are similar on a slow varying channel and a fast one.
The second step is to study the performance of a simple cooperative protocol with 2 senders and one recipient.

Xavier Lagrange
Guest researcher at KTH


ICT Labs wins race for EIT-KIC

Posted by: Jenny Minnema   /   0 Comment

EIT ICT Labs builds on five co-location centres – Berlin, Eindhoven, Helsinki, Paris, and Stockholm – to create a world-class network of innovation hotspots. These main hotspots are complemented with our extensive network of local and international innovation partners. EIT ICT Labs inspires creative students, researchers, and business people to embrace a risk taking and entrepreneurial attitude and help them to identify new business opportunities. EIT ICT Labs catalyzes the creation of strong ventures and help them to grow to become the future world leaders in the ICT arena. EIT ICT Labs makes Europe the preferred place for ICT innovation attracts top talent, R&D units of large companies and investors from all over the world.

–          Becoming a KIC is a tremendous opportunity for us to make Europe the global leader in ICT innovation, says Magnus Madfors, acting CEO of EIT ICT Labs. We have the team, the experience, and we are ready to start building a world class innovation ecosystem, turning the potential of the Future Information Society into benefits for the citizens of Europe and the world.

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