Cho đáp ứng tần số của bộ lọc thông cao lý tưởng lý tưởng pha không

$\left|H\left(e{}^{j\omega }\right)\right|=\{\begin{array}{}\end{array}$

$\left|H\left(e{}^{j\omega }\right)\right|=\{\begin{array}{c}1\\ \text{v}\text{o}\text{i}\{\begin{array}{c}-\pi \le \omega \le \\ \omega {}_{c{}_1}\le \omega \end{array}\\ 0\\ \text{v}\text{o}\text{i}\omega cc{}^{\left(-\pi \le \omega \le \pi \right)}\end{array}$

$\left|H\left(e{}^{j\omega }\right)\right|=\{\begin{array}{c}1\\ \text{v}\text{o}\text{i}\{\begin{array}{c}-\omega {}_{c{}_2}\le \omega \le \\ -\omega {}_{c{}_1}\le \omega \le \end{array}\\ \\ 0\end{array}\text{)}$

$\left|H\left(e{}^{j\omega }\right)\right|=\{\begin{array}{c}1\\ \text{v}\text{o}\text{i}\{\begin{array}{c}-\omega {}_{c{}_2}\le \omega \le \\ \omega {}_{c{}_1}\le \omega \le \end{array}\\ \\ 0\end{array}\text{)}$