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A 1 KW signal is transmitted using a c...

A ` 1 KW ` signal is transmitted using a communication channel which provides attenuatiom at the rate of ` - 2 dB per km` . If the communication channel has a total length of ` 5 km` , the power of the signal received is
[ gain in `dB = 10 log ((P_(0))/(P_(i)))]`

A

900W

B

100W

C

990W

D

1010W

Text Solution

Verified by Experts

The correct Answer is:
B
Loss suffered in the communication channel
`=(-2dB//km)5km=-10dB`
`therefore 10"log"(P_(0)//P_(i))=-10, "or log" (P_(0)//P_(i))=-1`
or `(P_(0)//P_(i))=10^(-1)=(1)/(10)`
or `P_(0)=P_(i)//10=(1kW)/(10)=100W`
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