# Solved Problems-6

Problem-6

Communication is to be established between two stations that are 1500 km apart. Derive the necessary formula and calculate the maximum frequency you may choose for communication using the ionosphere as a reflector if the height and the plasma frequency of the ionosphere at the point of reflection are respectively 250 km and 12 MHz. Assume the ionosphere to be thin and the earth to be flat.

Solution

Here,
The maximum usable frequency is given as,

*D*= 1500 km,*h*= 250 km,*f*_{c}= 12 MHz