Low-Pass Filter

H_LPF${\displaystyle (\omega )={\begin{cases}e^{-j\omega t_{d}},&pikeun|\omega |\leq \omega _{c}\\0,&pikeun\omega lianna\end{cases}}}$

Amplitudo jeung fase H_LPF${\displaystyle (\omega )}$ digambarkeun saperti di handap ieu:

LPF idéal ngaliwatkeun sakabéh komponén sinyal asupan nu frékuénsi radianna di sahandapeun ${\displaystyle \omega _{c}}$ tanpa distorsi; ${\displaystyle \omega _{c}}$ disebut frékuénsi pamotong (cutoff frequency). Sakabéh komponén sinyal saluhureun ${\displaystyle \omega _{c}}$ ditolak.

Réspon impuls tina LPF idéal bisa kapanggih ku cara nerapkeun kabalikan transformasi Fourier kana persamaan nu aya di luhur, sarta ngahasilkeun:

h_LPF${\displaystyle (t)={\frac {\sin \omega _{c}(t-t_{d})}{\pi (t-t_{d})}}.}$ 

Gambaran respon impuls tina LPF bisa ditingali saperti kieu:

• Filter
• Téori sistem LTI

1. Hsu, Hwei P., Schaum's Outline of Théory and Problems of Analog and Digital Communications, McGraw Hill, 1993