Basic Radar Theory - Ch 8

Question 1

Technique used by radar

Answer 1

Based on time between pulse out and the time back to calculate distance

When we Transmit we cannot receive

Question 2

Types of Radar

Answer 2

Parabolic Dish

Slotted planar array

Question 3

Beam width

Answer 3

Accuracy depends on how narrow the beam is, the narrow = the more accurate

The bigger the dish, the more accurate the beam will become

Question 4

Range

Answer 4

Time of travel of pulse x speed of light / 2

~ 12.34 micro seconds (1nm)

Question 5

MUTR

Answer 5

Max Unambiguous Theoretical Range

Question 6

PRI

Answer 6

Pulse Reference Interval

Question 7

PRF

Answer 7

Pulse Revision Frequency

Hight PRF = Long Range

Question 8

Range (unambiguous)

Answer 8

81000/PRF

Aerodrome = High PRF
Enroute = Low PRF

Question 9

Min Theoretical Range

Answer 9

The dead space in front of the radar

1 micro second = 150m
2 = 300
3 = 450

Question 10

Atmospheric Attenuation

Answer 10

Radio waves degraded over distance by water vapour (which it heats up), temp changes and pressure changes of the atmosphere

Question 11

Ducting

Answer 11

(Super refraction)

Bends the waves towards the surface of the earth

Question 12

Sub-Refraction

Answer 12

Bending the waves away from the surface of the earth

Question 13

Frequency Bands S and K

Answer 13

S - 2-4GHz

K - Airport Surveillance - 27-40GHz

Question 14

Types of ATC Radar

Answer 14

Area / Terminal Area Radar

Surveillance Radar

Ground Radar

Question 15

MTI

Answer 15

Moving Target Indicator

Takes away stationary object via Doppler shift

ATC can turn it on and off