Q-1 answer may not be more then three to foursentences.. (a) Difference between sampling and…

Q-1 answer may not be more then three to foursentences..

(a) Difference between sampling and quantization?

(b) What is on-off keying and carrier signal?

(c) Why we not use FSK in QAM?

(d) Why number of phase shift is more thenamplitude in QAM?

(e)Why we need NULL MODEM?