Sphere Decoding Complexity Exponent for Decoding Full-Rate Codes Over the Quasi-Static MIMO Channel
2012 (English)In: IEEE Transactions on Information Theory, ISSN 0018-9448, Vol. 58, no 9, 5785-5803 p.Article in journal (Refereed) Published
In the setting of quasi-static multiple-input multiple-output channels, we consider the high signal-to-noise ratio (SNR) asymptotic complexity required by the sphere decoding (SD) algorithm for decoding a large class of full-rate linear space-time codes. With SD complexity having random fluctuations induced by the random channel, noise, and codeword realizations, the introduced SD complexity exponent manages to concisely describe the computational reserves required by the SD algorithm to achieve arbitrarily close to optimal decoding performance. Bounds and exact expressions for the SD complexity exponent are obtained for the decoding of large families of codes with arbitrary performance characteristics. For the particular example of decoding the recently introduced threaded cyclic-division-algebra-based codes-the only currently known explicit designs that are uniformly optimal with respect to the diversity multiplexing tradeoff-the SD complexity exponent is shown to take a particularly concise form as a non-monotonic function of the multiplexing gain. To date, the SD complexity exponent also describes the minimum known complexity of any decoder that can provably achieve a gap to maximum likelihood performance that vanishes in the high SNR limit.
Place, publisher, year, edition, pages
2012. Vol. 58, no 9, 5785-5803 p.
Complexity, diversity multiplexing tradeoff (DMT), large deviations, space-time codes, sphere decoding (SD)
Electrical Engineering, Electronic Engineering, Information Engineering Computer Science
IdentifiersURN: urn:nbn:se:kth:diva-103141DOI: 10.1109/TIT.2012.2203581ISI: 000307892800011ScopusID: 2-s2.0-84865357206OAI: oai:DiVA.org:kth-103141DiVA: diva2:559387
FunderICT - The Next Generation
QC 201210092012-10-092012-10-042013-04-11Bibliographically approved