Question

If the error in delay is defined as Tg(ωk) – Tg(ω0) – Td(ωkk), then what is Tg(ω0)?

(a) Filter delay at nominal frequency in stop band

(b) Filter delay at nominal frequency in transition band

(c) Filter delay at nominal frequency

(d) Filter delay at nominal frequency in pass band

I got this question in an international level competition.

My query is from Design of IIR Filters in Frequency Domain in portion Digital Filters Design of Digital Signal Processing

Answer 1

Correct choice is (d) Filter delay at nominal frequency in pass band

For explanation: We are led to define the error in delay as Tg(ωk) – Tg(ω0) – Td(ωk), where Tg(ω0) is the filter delay at some nominal centre frequency in the pass band of the filter.