Radar Systems

Question 1

What are the major radar platforms?

Answer 1

1) Ground-based (GBR)
2) Sea-based (SBX)
3) Surveillance & Fire Control
4) Instrumentation
5) Side-Looking Airborne Radar (SLAR)
6) Airborne & ATC radars
7) Space-based (SBR)

Question 2

What are the 2 major radar types?

Answer 2

Imaging & Non-imaging

Question 3

A non-imaging airborne radar pointed straight down to the ground would be used as…

Answer 3

An altimeter

Question 4

What are the 3 radar types by configuration?

Answer 4

1) Monostatic
2) Bistatic
3) Multistatic

Question 5

What are the 2 types of radar by function?

Answer 5

Primary (reflection)
Secondary (transponder)

Question 6

What are the 2 radar configurations by waveform?

Answer 6

CW & pulsed

Question 7

What are the 3 radar types by antenna design?

Answer 7

1) Mechanical
2) Phased array
3) Synthetic aperture

Question 8

What type of antenna does a mechanical radar use?

Answer 8

Parabolic reflector, with Cassegrain design

Question 9

Components that work to redirect the energy in a phased array radar:

Answer 9

Phase shifters

Question 10

What are some characteristics of mechanical radars?

Answer 10

1) Single narrow beam
2) Typically cued where to look
3) Typically tracks only one object at a time
4) Cheaper and easier to operate
5) May produce imagery

Question 11

What are some limitations of mechanical radars?

Answer 11

1) Only able to track one object at a time
2) Difficulty with fast moving targets
3) Images require expert analysis
4) Susceptible to interference
5) Easier to Jam
6) Terrestrial Weather (High Winds/ Heavy Rain/Clutter)
7) Atmospheric Conditions

Question 12

What are some characteristics of phased array radars?

Answer 12

1) Very Agile
2) High Antenna Gain
3) Allows for scanning or search functions
4) Uses beam steering and beam forming
5) Track multiple objects
6) Typically not used for imagery

Question 13

What are some limitations of phased array radars?

Answer 13

1) Field of View (FOV) is limited to 120° Azimuth (per face)
2) Expensive to build and operate
3) Often more complex than mechanical
4) UHF radars have lower resolutions
5) Terrestrial Weather and Clutter
Interference

Question 14

What are the 2 characteristics of Synthetic Aperture radars?

Answer 14

1) Used for imagery
2) SLAR configuration

Question 15

Mechanical & phased array radars together are known as…

Answer 15

Real (physical) aperture

Question 16

A feedhorn mounted in front of a dish is an example of…

Answer 16

Cassegrain design

Question 17

What 2 things determine beam width?

Answer 17

1) Size of aperture
2) Tx wavelength

Question 18

Larger aperture = _________ beam width
Longer tx wavelength = ____________ beam width

Answer 18

Smaller
Smaller

Question 19

A phased array radar’s beam is adjusted (aimed) by adjusting…

Answer 19

Timing

Question 20

In a synthetic aperture radar, the motion of the platform is used to ________________, which results in ___________.

Answer 20

…increase the size of the aperture,
…increased imagery resolution

Question 21

Wavelength over aperture size = …

Answer 21

Beam width