'''Space–timeSpace–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–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 name="construction">{{notecite journal|performanceauthor=Vahid Tarokh, Nambi Seshadri, and A. R. Calderbank|title=Space–time codes for high data rate wireless communication: Performance analysis and code construction|journal=IEEE Transactions on Information Theory|pages=744–765|volume=44|issue=2|date=March 1998|id={{doi|10.1109/18.661517}}}}</ref><ref name="performance">{{cite journal|author=Vahid Tarokh, Ayman Naguib, Nambi Seshadri and A. Robert Calderbank|title=Space–time codes for high data rate wireless communication: performance criteria in the presence of channel estimation errors, mobility, and multiple paths|journal=IEEE Transactions on Communications|pages=199–207|volume=47|issue=2|date=February 1999|id={{doi|10.1109/26.752125}}}}</ref>▼
STTCs were discovered by [[Vahid Tarokh]] et. al in [[1998]].{{ref|construction}}{{ref|performance}}
==References==
<references />
#{{note|construction}}{{cite journal|author=Vahid Tarokh, Nambi Seshadri, and A. R. Calderbank|title=Space–time codes for high data rate wireless communication: Performance analysis and code construction|journal=IEEE Transactions on Information Theory|pages=744–765|volume=44|issue=2|date=March 1998|id={{doi|10.1109/18.661517}}}}
▲#{{note|performance}}{{cite journal|author=Vahid Tarokh, Ayman Naguib, Nambi Seshadri and A. Robert Calderbank|title=Space–time codes for high data rate wireless communication: performance criteria in the presence of channel estimation errors, mobility, and multiple paths|journal=IEEE Transactions on Communications|pages=199–207|volume=47|issue=2|date=February 1999|id={{doi|10.1109/26.752125}}}}
