论文标题
关于分布式Babai点计算的通信
On Communication for Distributed Babai Point Computation
论文作者
论文摘要
我们提出了用于计算Babai点的通信效率分布式协议,这是一个随机向量$ {\ bf x} \ in \ Mathbb {r}^n $在给定晶格中的近似点。我们表明,当$ {\ bf x} $相互独立时,该协议是最佳的,即将其最小化的总和速率最小化。然后,我们研究了误差概率,即Babai点与最近的晶格点不一致的概率。在二和三维中,这种概率被认为随着堆积密度而增长。对于更高的维度,我们使用概率理论的界限来估计某些众所周知的晶格的误差概率。我们的研究表明,对于统一的分布,对于晶格的尺寸,对于具有良好填料密度的晶格而言,误差概率变得很大。我们还考虑了通过在随机选择的晶格点添加高斯噪声来获得$ \ mathbf {x} $的情况。在这种情况下,当噪声方差足够小时,误差概率与晶格维度为零。在这种情况下,用于查找最近晶格点的分布式算法足以找到最近的晶格点。
We present a communication-efficient distributed protocol for computing the Babai point, an approximate nearest point for a random vector ${\bf X}\in\mathbb{R}^n$ in a given lattice. We show that the protocol is optimal in the sense that it minimizes the sum rate when the components of ${\bf X}$ are mutually independent. We then investigate the error probability, i.e. the probability that the Babai point does not coincide with the nearest lattice point. In dimensions two and three, this probability is seen to grow with the packing density. For higher dimensions, we use a bound from probability theory to estimate the error probability for some well-known lattices. Our investigations suggest that for uniform distributions, the error probability becomes large with the dimension of the lattice, for lattices with good packing densities. We also consider the case where $\mathbf{X}$ is obtained by adding Gaussian noise to a randomly chosen lattice point. In this case, the error probability goes to zero with the lattice dimension when the noise variance is sufficiently small. In such cases, a distributed algorithm for finding the approximate nearest lattice point is sufficient for finding the nearest lattice point.