Official PYQ · 2014Set 3 · Q18Discrete-time SignalsMCQ1 mark

GATE EC 2014 Set 3 Q18 — Discrete-time Signals

For an all-pass system $H(z)= \frac{(z^{-1}-b)}{(1-az^{-1})}$ , where $\mid H(e^{-j\omega }) \mid= 1,$ for all $\omega$ . If $\text{Re}(a)\neq 0, \: \text{Im}(a)\neq 0,$ then $b$ equals

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Published 10 Oct 2026

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