Question

With an increase in the value of M, the height of each side lobe ____________

(a) Do not vary

(b) Does not depend on value of M

(c) Decreases

(d) Increases

The question was asked in an international level competition.

This interesting question is from Design of Linear Phase FIR Filters Using Windows in section Digital Filters Design of Digital Signal Processing

Answer 1

The correct answer is (d) Increases

For explanation I would say: The height of each side lobes increase with an increase in M such a manner that the area under each side lobe remains invariant to changes in M.