IIR filter stands for infinite impulse response. In IIR filter design that are following criteria should be satisfied by designing a digital filter in the analog domain and transforming into the digital domain.
- IIR filter sometimes unstable
- IIR filter has difficult to design
- Lower filter order then a corresponding FIR filter
- Non zero pole exists in its transfer function
- Usually, have nonlinear property
- When phase distortion tolerable IIR usually favored
- IIR filter has lower computational
- IIR filter has less memory
- Less parameter to achieve a sharp cut off filter