SEW 11

Question 1

What is RADAR an acronym for?

Answer 1

Radio Detection and Ranging

Question 2

What is the ring of coastal early warning RADAR stations (first early warning RADAR network in the world) built by the Royal Air Force?

Answer 2

Chain Home

Question 3

What frequency range does RADAR use?

Answer 3

30 MHz to 100+ GHz

Question 4

What are the 4 principles of RADAR operation?

Answer 4

1. Transmitted Pulse
2. Propagation
3. Reflected Pulse
4. Echo is recorded and output to display

Question 5

What is the amount of the RADAR signal intercepted or redirected back toward the RADAR?

Answer 5

RADAR Cross-Section (RCS)

Question 6

What 4 factors affect the target RCS (how well the target reflects the RADAR signal)?

Answer 6

1. Size
2. Shape
3. Orientation
4. Composition

Question 7

What components make up TEARR Data?

Answer 7

Time
Elevation
Azimuth
Range
Range rate

Question 8

What determines vertical direction from the horizontal plane?

Answer 8

Elevation

Question 9

What is the minimum separation in elevation angle that a RADAR can detect between two targets?

Answer 9

Elevation resolution

Question 10

What determines horizontal direction from True North?

Answer 10

Azimuth

Question 11

What is the ability of a RADAR to separate two closely spaced targets at the same range?

Answer 11

Azimuth resolution

Question 12

What is the distance between the RADAR and target (product of duty cycle and total power [peak power x pulse width])?

Answer 12

Range

Question 13

What is based on the pulse width and is the ability to distinguish between different targets placed in the same angular direction but different distances?

Answer 13

Range resolution/ambiguity

Question 14

What pulse width picks up the finest details?

Answer 14

Short

Question 15

How can we achieve the energy of a long pulse with the resolution of a short pulse?

Answer 15

Modulate a square wave

Question 16

Range resolution and bandwidth have what kind of proportionality?

Answer 16

Inversely proportional

Question 17

What is the measure of how fast a target is moving toward or away from the RADAR?

Answer 17

Range rate

Question 18

What uses frequency shift echoed pulse to determine approach velocity?

Answer 18

Doppler processing

Question 19

What is the combination of azimuth, elevation, and range resolutions?

Answer 19

Resolution cell

Question 20

What are the 2 types of real aperture RADARs?

Answer 20

Mechanical and phased array

Question 21

What are the mechanical RADAR antenna types?

Answer 21

Parabolic reflector and Cassegrain design

Question 22

What are the characteristics of mechanical RADAR?

Answer 22

Single narrow beam
Track one object
Must be steered
Susceptible to interference/easy to jam
Susceptible to weather/atmospheric effects

Question 23

What works to redirect the energy on a phased array RADAR shifting the emitted wavefront?

Answer 23

Phase shifters

Question 24

What are the characteristics of phased array RADAR?

Answer 24

Uses beam steering/beam forming
High antenna gain
Scanning/search functions
Can track multiple objects
120° azimuth field of view
Susceptible to weather and clutter
Susceptible to interference

Question 25

What is an aircraft- or satellite-mounted imaging RADAR pointing perpendicular to the direction of flight?

Answer 25

Side-Looking Airborne RADAR (SLAR)

Question 26

What are the characteristics of Synthetic Aperture RADAR?

Answer 26

Used for imagery
Environmental considerations: ionospheric refraction/attenuation/dispersion and Faraday Rotation
Ducting
Scope clutter

Question 27

What is a mode of EM wave propagation where the waves are bent back toward the Earth’s surface?

Answer 27

Ducting

Question 28

What is caused by ground, sea, rain, birds, and insect returns?

Answer 28

Scope clutter

Question 29

What are 2 types of defensive countermeasure tactics used by military aircraft to protect against guided missiles?

Answer 29

Chaffs (RADAR jamming material) and air-launched decoys (clutter RADAR with false targets)