In lattice-coded multiple-input multiple-output (MIMO) systems, optimal decoding amounts to solving the closest vector problem (CVP). Embedding is a powerful technique for the approximate CVP, yet its remarkable performance is not well understood. In this paper, we analyze the embedding technique from a bounded distance decoding (BDD) viewpoint. 1/(2γ)-BDD is referred to as a decoder that finds the closest vector when the noise norm is smaller than λ1/{2γ), where λ1 is the minimum distance of the lattice. We prove that the Lenstra, Lenstra and Lovász (LLL) algorithm can achieve 1/{2γ)-BDD for γ ≈ O(2n over 4). This substantially improves the existing result γ = O(2n) for embedding decoding. We also prove that BDD of the regularized lattice is optimal in terms of the diversity-multiplexing gain tradeoff (DMT).
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机译:在点阵编码的多输入多输出(MIMO)系统中,最佳解码相当于解决最接近的向量问题(CVP)。对于近似CVP,嵌入是一种强大的技术,但其出色的性能尚未得到很好的理解。在本文中,我们从有界距离解码(BDD)的角度分析了嵌入技术。 1 /(2γ)-BDD称为解码器,当噪声范数小于λ 1 inf> / {2γ)时找到最接近的向量,其中λ 1 inf>为晶格的最小距离。我们证明,对于γ≈O(2 n over 4 sup>),Lenstra,Lenstra和Lovász(LLL)算法可以实现1 / {2γ)-BDD。这实质上改善了用于嵌入解码的现有结果γ= O(2 n sup>)。我们还证明,就分集复用增益折衷(DMT)而言,正则化格的BDD是最佳的。
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