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Which of the following statements are correct? A. M‐ary modulation scheme is preferable where the bandwidth requirement is important.

 

60. Which of the following statements are correct? 

A. M‐ary modulation scheme is preferable where the bandwidth requirement is important. 

B. M‐ary PSK system considers 'M' different phases in the range 'Ο€/2'. 

C. In M‐ary modulation scheme, only coherent detection is possible. 

D. M‐ary QAM scheme uses 'm^2 ' carrier signals having the same frequency. 


Choose the correct answer from the options given below: 

1. A and B only [Option ID = 3069] 

2. A and C only [Option ID = 3070] 

3. B and C only [Option ID = 3071] 

4. C and D only [Option ID = 3072


Answer: 2

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