Question

Which of the following defines the weighted approximation error?

(a) W(ω)[Hdr(ω)+Hr(ω)]

(b) W(ω)[Hdr(ω)-Hr(ω)]

(c) W(ω)[Hr(ω)-Hdr(ω)]

(d) None of the mentioned

This question was addressed to me by my school principal while I was bunking the class.

The question is from Design of Optimum Equi Ripple Linear Phase FIR Filters in division Digital Filters Design of Digital Signal Processing

Answer 1

Correct choice is (b) W(ω)[Hdr(ω)-Hr(ω)]

To explain: The weighted approximation error is defined as E(ω) which is given as

E(ω)=W(ω)[Hdr(ω)- Hr(ω)].