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arXiv · 1412.1257

Fast-Decodable Space-Time Codes for the $N$-Relay and Multiple-Access MIMO Channel

Amaro Barreal·Camilla Hollanti·Nadya Markin
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Abstract

In this article, the first general constructions of fast-decodable, more specifically (conditionally) $g$-group decodable, space-time block codes for the Nonorthogonal Amplify and Forward (NAF) Multiple-Input Multiple-Output (MIMO) relay channel under the half-duplex constraint are proposed. In this scenario, the source and the intermediate relays used for data amplification are allowed to employ multiple antennas for data transmission and reception. The worst-case decoding complexity of the obtained codes is reduced by up to $75%$. In addition to being fast-decodable, the proposed codes achieve full-diversity and have nonvanishing determinants, which has been shown to be useful for achieving the optimal Diversity-Multiplexing Tradeoff (DMT) of the NAF channel. Further, it is shown that the same techniques as in the cooperative scenario can be utilized to achieve fast-decodability for $K$-user MIMO Multiple-Access Channel (MAC) space-time block codes. The resulting codes in addition exhibit the conditional nonvanishing determinant property which, for its part, has been shown to be useful for achieving the optimal MAC-DMT.

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Amaro Barreal, Camilla Hollanti, Nadya Markin. 2015-12-10. Fast-Decodable Space-Time Codes for the $N$-Relay and Multiple-Access MIMO Channel. https://doi.org/10.1109/twc.2015.2496254

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