Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.
A space–time code (STC) is a method employed to improve the reliability of data transmission in wireless communication systems using multiple transmit antennas. STCs rely on transmitting multiple, redundant copies of a data stream to the receiver in the hope that at least some of them may survive the physical path between transmission and reception in a good enough state to allow reliable decoding. Space time codes may be split into two main types: Space–time trellis codes (STTCs) distribute a trellis code over multiple antennas and multiple time-slots and provide both coding gain and diversity gain.
vignette|redresse|Code morse international. En sciences et techniques, notamment en informatique et en théorie de l'information, un code est une règle de transcription qui, à tout symbole d'un jeu de caractères (alphabet source) assigne de manière univoque un caractère ou une chaîne de caractères pris dans un jeu de caractères éventuellement différent (alphabet cible). Un exemple est le code morse qui établit une relation entre lettres de l'alphabet latin et des séquences de sons courts et longs.
A diversity index is a quantitative measure that reflects how many different types (such as species) there are in a dataset (a community), and that can simultaneously take into account the phylogenetic relations among the individuals distributed among those types, such as richness, divergence or evenness. These indices are statistical representations of biodiversity in different aspects (richness, evenness, and dominance).
Designs for transmit alphabet constrained space-time codes naturally lead to questions about the design of rank distance codes. Recently, diversity embedded multi-level space-time codes for flat fadin
2008
,
Rate and diversity impose a fundamental trade-off in wireless communication. High-rate space-time codes come at a cost of lower reliability (diversity), and high reliability (diversity) implies a lowe
Rate and diversity impose a fundamental trade-off in communications. This tradeoff was investigated for Intersymbol Interference (ISI) channels in [7]. A different point of view was explored in [4] wh