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arXiv · 0811.4354

Soft-Input Soft-Output Sphere Decoding

Christoph Studer·Helmut Bölcskei
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Abstract

Soft-input soft-output (SISO) detection algorithms form the basis for iterative decoding. The associated computational complexity often poses significant challenges for practical receiver implementations, in particular in the context of multiple-input multiple-output wireless systems. In this paper, we present a low-complexity SISO sphere decoder which is based on the single tree search paradigm, proposed originally for soft-output detection in Studer et al., IEEE J-SAC, 2008. The algorithm incorporates clipping of the extrinsic log-likelihood ratios in the tree search, which not only results in significant complexity savings, but also allows to cover a large performance/complexity trade-off region by adjusting a single parameter.

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Christoph Studer, Helmut Bölcskei. 2008-11-26. Soft-Input Soft-Output Sphere Decoding. https://arxiv.org/abs/0811.4354

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