矢量量化码书设计本质是搜索训练矢量的最佳分类。

VQ codebook design is essentially a classification of training vectors.

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本文将信号处理中的子空间方法同分层空时码的编码结构相结合，提出了一种垂直分层空时编码，实现了无需训练序列的信道估计。

In this paper, by combining the subspace method with layered space-time codes, we propose a vertical layered space-time code and accomplish the channel estimation without the training symbols.

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目前，一种普遍的解决方法是将空时码与正交频分复用（OFDM）相结合，但需要假定信道变化缓慢，从而有足够的时间通过发送训练序列来进行信道估计。

Now, a general solution is that combining STC with OFDM, but it is supposed that the channel changes slowly, so there is enough time to transmit the training sequence for channel estimation.

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