DOPPLER RADAR SYSTEMS

Question 1

Doppler operates on the principle that …… between a transmitter and receiver will cause the received frequency to …… if the transmitter and receiver are moving ….. .

Answer 1

relative motion, decrease, apart

Question 2

An aeroplane is flying at 486 kt directly towards a beacon transmitting on a frequency of 12 GHz. The change in frequency observed will be:

Answer 2

10 kHz

Question 3

Due to ‘Doppler’ effect an apparent decrease in the transmitted frequency, which is proportional to the transmitter’s velocity, will occur when:

Answer 3

the transmitter moves away from the receiver

Question 4

When an aircraft is flying directly away from a transmitter, transmitting on a frequency of 15 GHz, a frequency shift of 6.0 kHz is measured. The speed of the aircraft is:

Answer 4

222 kt

Question 5

The change in frequency measured in an aircraft from a radio transmission reflected from the ground is used to determine:

Answer 5

the drift and groundspeed of the aircraft