• The frequency shift that occurs, when there is a relative motion between the transmitting station and a remote object is known as Doppler effect.
• By measuring the amount of frequency, difference between the transmitted and the reflected signal,
• It is possible to determine the relative speed between the RADAR unit and the observed object.

V = 1.1 f x $\lambda$

Where

v = relative speed between the two objects (m/s)

F = frequency difference between the transmitted and reflected signals (Hz)

$\lambda$ = wavelength of transmitted signal (m)

d. State the reason for difference in uplink and downlink frequency in satellite communication.