Đáp ứng biên độ của bộ lọc số thông cao lý tưởng được định nghĩa

$\left|H\left(e{}^{j\omega }\right)\right|=\{\begin{array}{c}1\\ \text{v}\text{o}\text{i}\{\begin{array}{c}-\frac{\pi }{2}\le \omega \le \\ \frac{\pi }{2}\le \omega \le \end{array}\\ 0\\ \end{array}\text{.}$

$\left|H\left(e{}^{j\omega }\right)\right|=\{\begin{array}{c}1\\ \text{v}\text{o}\text{i}\{\begin{array}{c}-\pi \le \omega \le \\ \pi \le \omega \le \end{array}\\ 0\\ \end{array}$

$\left|H\left(e{}^{j\omega }\right)\right|=\{\begin{array}{c}1\\ \\ \text{v}\text{o}\text{i}-\pi \le \omega \le \\ \\ 0\\ \text{v}\text{o}\text{i}\omega \text{c}\text{ò}\text{n}\text{l}\text{ą}\end{array}$

$\left|H\left(e{}^{j\omega }\right)\right|=\{\begin{array}{c}1\\ \text{v}\text{o}\text{i}\pi \le \omega \\ 0\\ \text{v}\text{o}\text{i}\omega \text{c}\text{ò}\text{r}\left(-\pi \le \omega \le \pi \right)\end{array}$