# Communication System

Communication System
Question:-
Option (A)
4 MHz
Option (B)
4 GHz
Option (C)
8 MHz
Option (D)
8 GHz
Correct Option:
D
Question Solution:
fs = 2fm
= 2 x 4 GHz
= 8 GHz
Question:-
Option (A)
(SNR)s = 2(SNR)i
Option (B)
(SNR)s = (SNR)i
Option (C)
(SNR)s = 4(SNR)i
Option (D)
(SNR)s = 1/2(SNR)i
Correct Option:
B
Question:-
Option (A)
545 kHz
Option (B)
1 MHz
Option (C)
1455 kHz
Option (D)
1910 kHz
Correct Option:
D
Question Solution:
fsi = fs + 2fi
= 1000 + 2 x 455
fsi = 1910 kHz
Question:-
Option (A)
Both A and R are true and R is the correct explanation of A
Option (B)
Both A and R are true but R is not the correct explanation of A
Option (C)
A is true but R is false
Option (D)
A is false but R is true
Correct Option:
C
Question Solution:
Coherent FSK is optimum and more sophisticated
Question:-
Option (A)
Increases by 50%
Option (B)
Increases by 75%
Option (C)
increases by 100%
Option (D)
remains unaffected
Correct Option:
A
Question Solution:
pt = pc {1+(m2a/2)}
if ma =0
\ pt1 = pc
if ma =1
pt2 = (3/2)pc
Δpt = pt2-pt1 = (1/2)pc
\ increases by 50%