Question

A person with a receiver is 5 km away from the transmitter. What is the distance that this person must move further to detect a 3 – dB decrease in signal strength?

(a) 942 m

(b) 2070 m

(c) 4978 m

(d) 5320 m

Answer 1

The correct option is (B)

Explanations:

Distance between transmitter and person with receiver is 5 km

From the position P1 person having receiver moves some distance to detect 3 dB decrease is signal strength. Field strength at P2 is 1/√2 times field strength at position 1.

E at point P1 is E1

Thus distance moved from point 1 to point 2 = 2070 m