We start by identifying a relatively efficient version of sphere decoding algorithm (SDA) that performs exact maximum-likelihood (ML) decoding. We develop novel algorithms based on an improved increasing radius search (IIRS), which offer error performance and decoding complexity between two extremes: the ML receiver and the nulling-canceling (NC) receiver with detection ordering. With appropriate choices of parameters, our IIRS offers the flexibility to trade error performance for complexity. We provide design intuitions and guidelines, analytical parameter specifications, and a semianalytical error-performance analysis. Simulations illustrate that IIRS achieves considerable complexity reduction, while maintaining performance close to ML.
Bibliographical noteFunding Information:
Paper approved by B. Hochwald, the Editor for Communication and Coding Theory of the IEEE Communications Society. Manuscript received October 22, 2003; revised June 2, 2004 and October 10, 2004. This work was supported by the Army Research Office/Collaborative Technology Alliance (ARO/CTA) under Grant DAAD19-01-2-0011. This paper was presented in part at the IEEE Wireless Communication and Networking Conference, Atlanta, GA, March 2004.
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- Multiple-input multiple-output (MIMO) decoding
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