Space–time trellis code: Difference between revisions

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'''Space–time trellis codes (STTCs)''' are a type of [[space–time code]] used in [[multiple-input multiple-output|multiple-antenna]] [[wireless|wireless communications]]. This scheme transmits multiple, [[redundancy (information theory)|redundant]] copies of a [[convolutional code|trellis (or convolutional) code]] distributed over time and a number of [[antenna (radio)|antennas]] ('space'). These multiple, 'diverse' copies of the data are used by the receiver to attempt to reconstruct the actual transmitted data. For a STC to be used, there must necessarily be multiple ''transmit'' antennas, but only a single ''receive'' antennas is required; nevertheless multiple receive antennas are often used since the performance of the system is improved by so doing.

In contrast to [[space-timespace–time block code]]s (STBCs), they are able to provide both coding gain and diversity gain and have a better [[bit error rate|bit-error rate]] performance. However, being based on [[convolutional code|trellis codes]], they are more complex than STBCs to encode and decode; they rely on a [[Viterbi algorithm|Viterbi decoder]] at the receiver where STBCs need only [[linear]] processing.

STTCs were discovered by [[Vahid Tarokh]] et. al in [[1998]].{{ref|construction}}{{ref|performance}}