Zero

Wider than a wide pulse spectrum

Constant

Narrow

Smooth the signal

 Center zero frequency in the spectrum

Remove harmonics

Increase amplitude

Waveform becomes smoother only

 Approximation becomes closer to the original waveform

Frequency decreases

Signal becomes random

Amplify signals

Remove noise from signals

Represent periodic signals using sinusoids

Compress signals

Low frequencies

Fundamental frequencies

High frequencies

DC components

zplane()

stepz()

mean()

 subplot()

 Input becomes zero

Numerator becomes zero

 Output becomes infinite

 Denominator becomes zero

IIR, Low Pass

FIR, Low Pass

FIR, High Pass

IIR, High Pass

Bandstop

Bandpass

Lowpass

Highpass

 Shifted

 Attenuated

Amplified