# MCQs on MTI, Pulse Doppler Radars

## MCQs on MTI, Pulse Doppler Radars

### Multiple Choice Questions MTI andPulse Doppler Radar

1. The characteristic feature of coherent MTI radars is that the
• transmitted signal should be out of phase with the reference signal in the receiver.
• the transmitted signal should be equal in magnitude to the reference signal.
• the transmitted signal should be coherent with the reference signal in the receiver.
• the transmitted signal should not be equal to the reference signal in the receiver.

Answer: the transmitted signal should be coherent with the reference signal in the receiver.

2. The Doppler frequency shift produced by a moving target may be used in pulse radar to

• combine moving targets from desired stationary objects.
• determine the relative velocity of a target.
• separate desired moving targets from desired stationary objects.
• determine the displacement of a target.

Answer: determine the relative velocity of a target.

3. The limitation of the pulse MTI radar that does not occur with the CW radar

• is blind speed
• is delay lines
• requires more operating powers
• requires complex circuitry

4. The output of the MTI receiver phase detector should be quantized into a sequence of digital words by using

• a digital quantizer
• a digital phase detector
• digital delay lines
• a digital filter

5. A simple MTI delay line canceller is an example of

• a frequency domain filter
• a high-pass filter
• an active filter
• a time-domain filter

6. The effect of blind speed can be significantly reduced in

• delay line cancellers
• staggered PRF–MTI
• pulse cancellers

7. It provides stated probabilities of detection and false alarm:

• clutter attenuations
• clutter ratio
• cancellation ratio
• clutter visibility factor

8. An MTI radar that uses amplitude fluctuations is

• coherent
• a pulse Doppler
• non coherent

9. The blind speeds of two independent radars operating at the same frequency will be different if their

• amplitudes are different
• blind speeds are different
• pulse repetition frequencies are different
• pulse intervals are different

Answer: pulse repetition frequencies are different

10. The clutter-rejection notches may be widened by passing the output of the delay line canceller through a

• Coho
• Stalo
• second delay line canceller
• pulse canceller

11. Two- and three-pulse cancellers are examples of

• MTI filters

12. The following techniques are Doppler filtering techniques that reject stationary clutter and where radial velocity is not measured:

• moving target indicator (MTI)
• MTD
• pulse Doppler

13. The following are regions of Doppler space where targets with those Doppler velocities cannot be detected:

• blind speeds
• delay line cancellers
• staggered PRF
• clutter visibility factor

14. Ambiguities in range and Doppler velocity can be resolved by transmitting multiple bursts of pulses

• with constant PRF
• with different PRFs
• with two PRFs
• none

15. Unambiguous range measurements and ambiguous velocity measurements are caused by

• low PRF
• high PRFs
• medium PRFs
• high PRF

16. Ambiguous range measurements and ambiguous velocity measurements are caused by

• low PRF
• high PRFs
• medium PRFs
• high PRF

17. Very ambiguous range measurements and unambiguous velocity measurements are caused by

• low PRF
• high PRFs
• medium PRFs
• high PRF

18. Staggering or changing the time between pulses will

• raise the blind speed
• lower the blind speed
• maintain the same blind speed
• none

19. The following radar does not provide the target velocity estimation:

• MTI
• both
• none