EQPS - Radar Principles (Primary)

Question 1

What do Surveillance systems enable ATS provider to do? (3)

Answer 1

1. Keep aircraft safe
2. Work efficiently
3. Accurately depicting the position and level and various other information on a
   visual display

Question 2

What do we use Radar for? (5)

Answer 2

1. Area control
2. Approach control
3. Aerodrome Control (ATM)
4. Air
5. Ground

Question 3

What do we use Radar for in Area Control? (3)

Answer 3

Wide area
Terminal control
Air Defence

Question 4

What do we use Radar for in Approach Control? (3)

Answer 4

1. Within defined area of responsibility
2. Vectoring to final approach
3. SRA

Question 5

What do we use Radar for in Aerodrome Control? (1)

Answer 5

ATM

Question 6

What do we use Radar for in Air Control? (2)

Answer 6

1. Traffic integration
2. Approach monitoring

Question 7

What do we use Radar for in ground Control? (3)

Answer 7

1. Runway Protection
2. Monitoring ground movements
3. Hazard identification

Question 8

How does radar work?

Answer 8

Sound travels at 330m per second at msl

Question 9

What does RADAR stand for (1)

Answer 9

RAdio
Detection
And
Ranging

Question 10

What are the two types of radar used in ATC? (2)

Answer 10

1. Primary radar
2. Secondary radar

Question 11

What does primary radar transmit? (1)

Answer 11

Radio energy

(Determines whether any of the energy is reflected)

Question 12

Wilkins / Watson Watt Experiment diagram

Answer 12

26th February 1935

Question 13

What waveband spectrum is ATC radar within?

Answer 13

1mm to 100cm

Question 14

What is considered when choosing a Wavelength? (1)

Answer 14

The higher frequency/shorter wavelength is more attenuated due to its increased interaction with air molecules

Question 15

What wavelength ranges are:
- SMR, A/C weather radar
- Primary Approach radar
- Primary Area radar

Answer 15

2-3cm: Surface Movement Radar, Aircraft Weather Radar

3cm-10cm: Primary Approach Radar

23cm-50cm: Primary Area Radar

Question 16

How many pulses does a radar transmit per second? (1)

Answer 16

1200 pulses (67nm approx.)

Question 17

What is the definition of a PSR blip? (1)

Answer 17

The visual indication, in non symbolic form, on a situation display of the position of an aircraft obtained by primary radar.

Question 18

What is the definition of Position Indication? (1)

Answer 18

A generic term for the visual indication, in non-symbolic and/or symbolic form, on a situation display of the position of an aircraft, aerodrome vehicle or other object

Question 19

What is the definition of Position Symbol? (1)

Answer 19

A visual indication in symbolic form, on a situation display, of the position of an aircraft, aerodrome vehicle or other object obtained after automatic processing of positional data derived from any source

Question 20

What is the definition of Radar Contact? (1)

Answer 20

The situation which exists when the radar position of a particular aircraft is seen and identified on a situation display. (ICAO)

Question 21

What is the definition of Radar Control? (1)

Answer 21

Term used to indicate that radar-derived information is employed directly in the provision of air traffic control service

Question 22

What is the definition of Situation Display? (1)

Answer 22

An electronic display depicting the position and movement of aircraft and other information as required. (ICAO)

Question 23

What are the three basic blocks of a Radar System? (3)

Answer 23

1. Transmission
2. Reception
3. Display

”TRD”

Question 24

What are the 4 Primary Radar components? (4)

Answer 24

1. Transmitter
2. Duplexer
3. Receiver
4. Display

Question 25

What does a **Transmission block** do? (1)

Answer 25

Prepares the energy for transmission and radiates it through the aerial

Question 26

What are the 3 units of a **Transmission block**? (3)

Answer 26

1. Trigger Unit (Master Timer) 2. Transmitter Unit 3. Modulator Unit **”TTM”**

Question 27

What is a **Trigger Unit**? (2)

Answer 27

- A device whose output is used to initiate action - Each pulse fires the **MODULATOR**

Question 28

What is a **Transmitter Unit**? (2)

Answer 28

- The output of the Transmitter is a series of pulses of radar energy - Each pulse thus produced is delivered to the aerial

Question 29

What is a **Modulator Unit**? (1)

Answer 29

Modulator is a kind of on/off switch for the **TRANSMITTER**

Question 30

What does the **Reception Block** do? (2)

Answer 30

- Detects energy reflected from objects. - The weak signal must be amplified and suitably treated by the **HIGH GAIN LOW NOISE RECEIVER**

Question 31

What does the **Aerial Unit** do? (2)

Answer 31

- The energy from the transmitter is radiated from the aerial at regular intervals. The radiated energy is generally confined within a fairly narrow beam. - The Duplexer, (a Transmit-Receive (TR) switch) during the interval between transmissions, connects the receiver and isolates the transmitter.

Question 32

What does the **Display Block** do? (2)

Answer 32

-Boosted clean received signal is displayed on the display unit (situation display) - Range is calculated in the time base unit