sm10_6

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Problem 10.6 Compare the transmission bandwidth required for binary PAM and BPSK 
modulation, if both signals have a data rate of 9600 bps and use root-raised cosine pulse 
spectrum with a roll-off factor of 0.5. 
 
Solution 
For BPSK modulation (bandpass signal), the transmission bandwidth is 12
2T
B
T
β+= × , 
where β is the roll-off factor (0.5) and T is the symbol duration (1/9600 sec). Therefore, 
BT = (1+0.5)×9600 = 14.4 kHz. 
 
For binary PAM modulation (baseband signal), 1
2T
B
T
β+= = 7.2 kHz. 
 
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