设观测信号\(x(t)\)为期望信号\(s(t)\)和噪声信号\(n(t)\)的叠加，也即 \[\begin{aligned} x(t) = s(t) + n(t). \end{aligned}\] 其中，\(s(t)\)和\(n(t)\)是宽平稳过程，且相互联合宽平稳，观测信号\(x(t)\)和期望信号\(s(t)\)的自相关函数和互相关函数分别为\(R_x(\tau)\)、\(R_s(\tau)\)和\(R_{sx}(\tau)\)，功率谱密度函数及其互功率谱密度函数分别为\(S_x(f)\)、\(S_s(f)\)和\(S_{sx}(f)\)。
[Read More]ZC
Introduction
The Zadoff-Chu (ZC) sequence1 is named after Solomon A. Zadoff and D. C. Chu, which is a constant amplitude zero auto-correlation (CAZAC) sequence2 with its cylically shifted versions are zero correlated, i.e. orthogonal to each other. A ZC sequence without cyclic shift is termed a root sequence, which can be expressed as \[\begin{aligned} x_u(n) = e^{-j\frac{\pi u n (n+1+2q)}{L}}, \quad n = 0, 1, \ldots, L-1, \end{aligned}\] where \(u\) is the index of the root sequence, \(L\) is the length and \(q \in \mathbb{Z}\).
归去来兮辞
序
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C++ - Thread Pool
Introduction
Threadpool is a C++ thread pool written by Philipp Henkel based on boost library. It provides a variety of thread pools with easy usage.