Question

As the roll off factor in raised cosine rolloff filter __________ the occupied bandwidth ________

(a) Increases, decreases

(b) Decreases, constant

(c) Increases, increases

(d) Decreases, increases

I have been asked this question during an online interview.

I need to ask this question from Pulse Shaping Techniques in portion Modulation Techniques for Mobile Radio of Wireless/Mobile

Answer 1

Right answer is (c) Increases, increases

The best I can explain: As the rolloff factor increases, the bandwidth of the filter also increases and the time sidelobe levels decrease in adjacent symbol slots. Thus, it implies that increasing rolloff factor decreases the sensitivity to timing jitter but increases the occupied bandwidth.