Sommaire

  • Cet exposé a été présenté le 21 novembre 2003.

Description

  • Orateur

    Jean-Claude Belfiore - ENST

The need of high data rates on the radio channel (WiFi and its future for example) explains the increasing number of researchers working on space-time codes. Preparing Wireless IP systems, some companies and some researchers are promoting the use of non coherent space-time codes.<br/> We show that designing a non coherent space-time code is equivalent to finding some good packings on the Grassmann manifold. But the minimum distance of the packing is not a Euclidean distance and the codes need to be decoded with a "not too complex" algorithm. To solve this problem, we propose a new family of codes on the Grassmann manifold as well as the associated performances.

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