Question

A 50 MHz sky wave sky wave takes 4.04 ms to reach a receiver via re-transmission from a satellite 600 km above earth's surface. Assuming re-transmission time by satellite negligible, find the distance between source and receiver. If communication between the two was to be done by Line of sight (LOS) method,what should be the size of transmitting antenna ?

Answer 1

Given - Frequency=50 MHz

Total Time taken=4.04 ms=4.04×10⁻³s

Let x be the distance of satellite from the surface of earth

To find- Distance between source and receiver

speed=distance/time

=2x/t

x=(3×10⁸×4.04×10⁻³)/2

x=606km

d=√x²-h²

d=√606²-600²

d=85km

therefore distance between source and receiver is 2d=170 km