Optimal throughput-diversity-delay tradeoff in MIMO ARQ block-fading channels
2008 (English)In: IEEE Transactions on Information Theory, ISSN 0018-9448, Vol. 54, no 9, 3968-3986 p.Article in journal (Refereed) Published
In this paper, we consider an automatic-repeat-request (ARQ) retransmission protocol signaling over a block-fading multiple-input-multiple-output (MIMO) channel. Unlike previous work, we allow for multiple fading blocks within each transmission (ARQ round), and we constrain the transmitter to fixed rate codes constructed over complex signal constellations. In particular, we examine the general case of average input-power-constrained constellations with a fixed signaling alphabet of finite cardinality. This scenario is a suitable model for practical wireless communications systems employing orthogonal frequency division multiplexing (OFDM) techniques over a MIMO ARQ channel. Two cases of fading dynamics are considered, namely, short-term static fading wherechannel fading gains change randomly for each ARQ round, and long-term static fadingwhere channel fading gains remain constant over all ARQ rounds pertaining to a given message. As our main result, we prove that for the block-fading MIMO ARQ channel with a fixed signaling alphabet satisfying a short-term power constraint, the optimal signal-to-noise ratio (SNR) exponent is given by a modified Singleton bound, relating all the system parameters. To demonstrate the practical significance of the theoretical analysis, we present numerical results showing that practical Singleton-bound-achieving maximum distance separable codes achieve the optimal SNR exponent.
Place, publisher, year, edition, pages
2008. Vol. 54, no 9, 3968-3986 p.
Automatic-repeat-request (ARQ) retransmission protocols, Block-fading channels, Complex signal constellations, Incremental redundancy coding, Multiple-input-multiple output (MIMO) channels, Throughput-diversity-delay tradeoff
IdentifiersURN: urn:nbn:se:kth:diva-62615DOI: 10.1109/TIT.2008.928264ISI: 000258913400007OAI: oai:DiVA.org:kth-62615DiVA: diva2:480796
QC 201202072012-01-192012-01-192012-02-07Bibliographically approved