Question

7. (5 Points) In a Polar NRZ format, a) complete pulse duration b) O half pulse duration c) O 1 is transmitted by a positive pulse and O is transmitted as a negative pulse d) 1 is transmitted by a positive pulse and O is transmitted as a zero e) None of the mentioned EXPLANATION: 8. (5 Points) QAM modulation scheme where each symbol consit of a) 4 bits b) 2 bits c) O 1 bit d) IM the number of bit depend on requirements e) None of the mentioned EXPLANATION: 9. (5 Points) ASK modulated signal has the bandwidth a) b) c) d) Double the bandwidth of the baseband Half the bandwidth of the baseband Same the bandwidth of the baseband None of the mentioned Power EXPLANATION:

Answer 1

7.

NRZ stands for Non Return To Zero in which HIGH input as treated as 1 and  LOW input is treated as -1 .

So answer is c.

1 is transmitted by positive pulse and 0 is transmitted as negative pulse .

8.

QAM stands for quadrature amplitude Modulation in which two amplitude modulated signal are super imposed.

For M-QAM ,Here M is the number of bits that is transmitted that is transmitted over channel.

So answer is D i.e. M the number of bit depends upon requirement .

9.

Amplitude Shift Key ( ASK )

B_T= (1+alpha) B_W

Where B_w is the Bandwidth of base band signal

For ASK alpha =1

So BT= 2* B_W

So option is A i.e. Double the bandwidth of baseband signal