名称 | 时域 \(f(k)\) | Z域 \(F(z)\) |
---|---|---|
线性 | \(a_1 f_1(k) + a_2 f_2(k)\) | \(a_1 F_1(z) + a_2 F_2(z)\) |
移序(移位)性 | \(f(k+m) \quad (m > 0)\) | \(z^m F(z) - \sum_{k=0}^{m-1} f(k) z^{m-k-1}\) |
\(f(k-m)u(k-m) \quad (m > 0)\) | \(z^{-m} F(z)\) | |
比例性(尺度变换) | \(a^k f(k)\) | \(F\left(\frac{z}{a}\right)\) |
Z域微分 | \(k f(k)\) | \(-z \frac{dF(z)}{dz}\) |
Z域积分 | \(\frac{1}{k} f(k) \quad (a > 0)\) | \(\int_{z}^{\infty} F(v) v^{-(a+1)} dv\) |
时域卷积 | \(f_1(k) * f_2(k)\) | \(F_1(z) F_2(z)\) |
时域相乘 | \(f_1(k) \cdot f_2(k)\) | \(\frac{1}{2\pi j} \oint_C F_1(v) F_2\left(\frac{z}{v}\right) \frac{dv}{v}\) |
序列求和 | \(\sum_{n=0}^{\infty} f(n)\) | \(\frac{z}{z-1} F(z)\) |
初值定理 | \(f(0) = \lim_{z \to \infty} F(z)\) | |
\(f(m) = \lim_{z \to \infty} z^m \left[ F(z) - \sum_{k=0}^{m-1} f(k) z^{-k} \right]\) | ||
终值定理 | \(f(\infty) = \lim_{z \to 1} (z-1) F(z)\) |