A discrete-time all-pass system has two of its poles at 0.25∠0° and 2∠30° which one of the following statements about the system is TRUE?
A. It has two more poles at 0.5∠30° and 4∠0°
B. It is stable only when the impulse response is two-sided
C. It has constant phase response over all frequencies
D. It has constant phase response over the entire z-plane
Answer: Option B

Join The Discussion