Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Radio Navigation > RADAR (Primary) (21-05-18) > Flashcards

RADAR (Primary) (21-05-18) Flashcards

1
Q

What does RADAR stand for?

A

RAdio Detection And Ranging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What frequency band does RADAR use?

A

SHF & UHF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the principle of operation of RADAR?

A

EM radio energy is transmitted and then reflected energy is used to work out where objects are

Slant range and pulse timing is used for vertical position

Position of antenna at point of transmission/receipt is used for azimuth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the features of the Plan Position Indicator (PPI)?

A

Gives slant range and bearing of targets

Groud reflection is close to centre

Shows weather clutter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the principle of operation of a Plan Position Indicator (PPI)?

A

A powerful transmitter (Magnetron) transmits a signal

This is reflected by targets

A receiver (Klystron) picks up the now weaker, reflected signal

Only one of these parts can be working at any one time via the duplex switch.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do you work out the range of a target from RADAR, given the time between emission and reception?

A

Range (nm) = (time between emission and receiption) / 12.36

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the pulse width of RADAR?

A

The amount of time transmitting a pulse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What determines the minimum range of RADAR and why?

A

Pulse width

Due to still transmitting while reception occurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What determines the maximum range of RADAR and why?

A

Pulse recurrence period (PRP) - time between 2 successive pulse transmissions

Longer PRP allows time for reflected energy to return

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is pulse reccurrence frequency (PRF)

A

The amount of pulses plus intervals in 1 second

1/PRP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the relationship between range and power of RADAR?

A

Transmitted signal

Range prop 4throot(P)

Reflected signal

Range prop root(P)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the MTR of RADAR?

A

MTR = 81000/PRF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a better alternative to parabolic reflector for RADAR and why?

A

Flat plate antenna

Produces narrower band width

Condiserably reduces side lobes and loss of energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do you calculate beamwidth a signal?

A

Beamwidth (deg) = 70lambda/D

D = dish diameter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a moving target indicator (MTI) and what are it’s advantages and disadvantages?

A

Detects Doppler shift in a RADAR return

adv

removes ground and weather clutter

disadv

will not show targets moving tangentially to the system or CBs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What factors affect the make range of RADAR?

A

Transmission power

Characteristics of reflected objects (material, size, shape, orientation)

Aircraft height and RADAR height

Atmospheric conditions (sub & super refraction)

Pulse width

Radio Navigation (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions