11 Questions

Questions

	1.	The factor which determines the maximum range of a radar is:
		a.	pulse repetition rate
		b.	pulse width
		c.	power
		d.	beamwidth
	2.	The main advantage of continuous wave radars is:
		a.	no maximum range limitation
		b.	better range resolution
		c.	no minimum range limitation
		d.	better range resolution
	3.	If the PRF of a primary radar is 500 pulses per second, the maximum range will be:
11		a.	324 NM
		b.	300 NM
Questions		c.	162 NM
		d.	600 NM
	4.	To double the range of a primary radar would require the power to be increased by
		a factor of:

a.2

b.4

c.8

d.16

5.The time between the transmission of a pulse and the reception of the echo from a target is 1720 microseconds. What is the range of the target?

a.139 km

b.258 km

c.278 km

d.516 km

6.A radar is required to have a maximum range of 100 NM. What is the maximum PRF that will achieve this?

a.1620 pulses per second (pps)

b.1234 pps

c.617 pps

d.810 pps

7.If the PRI of a radar is 2100 microseconds, the maximum range of the radar is:

a.170 NM

b.315 NM

c.340 NM

d.630 NM

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			Questions		11
	8.	To improve the resolution of a radar display requires:
		a.	a narrow pulse width and a narrow beamwidth
		b.	a high frequency and a large reflector
		c.	a wide beamwidth and a wide pulse width
		d.	a low frequency and a narrow pulse width
	9.	An advantage of a phased array (slotted antenna) is:
		a.	better resolution
		b.	less power required
		c.	reduced side lobes and clutter
		d.	all of the above
	10.	An echo is received from a target 900 microseconds after the pulse was transmitted.
		The range to the target is:
		a.	73 NM
		b.	270 NM
		c.	135 NM	11
		d.	146 NM
					Questions
	11.	The factor which limits the minimum detection range of a radar is:
		a.	pulse repetition interval
		b.	transmitter power
		c.	pulse width
		d.	pulse repetition frequency
	12.	The use of Doppler techniques to discriminate between aircraft and fixed objects
		results in second trace returns being generated. These are removed by:
		a.	using a different frequency for transmission and reception
		b.	jittering the PRF
		c.	making regular changes in pulsewidth
		d.	limiting the power output of the radar
	13.	A radar is designed to have a maximum range of 12 km. The maximum PRF that
		would permit this is:
		a.	25 000 pps
		b.	6700 pps
		c.	12 500 pps
		d.	13 400 pps
	14.	The bearing of a primary radar is measured by:
		a.	phase comparison
		b.	searchlight principle
		c.	lobe comparison
		d.	DF techniques

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11 Answers

Answers

1	2	3	4	5	6	7	8	9	10	11	12
a	c	c	d	b	d	a	a	d	a	c	b
13	14
c	b

Answers 11

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