Radar

Question 1

Radar

Answer 1

utilize pulse techinque, it find the direction and the range u by showing the echo

Question 2

minimum range

Answer 2

depend of the pulse lenght and is the lambda/2

Question 3

PRF

Answer 3

pulse recurrence frequency -> it is the number of pulse trasmitted in one second

Question 4

PRI

Answer 4

is the time interval betwen t2 pulses = 1/PRF

Question 5

maximum range theoretical

Answer 5

depend from the PRF light speed / PRF * 2
lower PRF bigger range
each pulse most be allowed to travel and come back

Question 6

practil range

Answer 6

is less because the the trce on CRT need a time to come back in his original position, this period is called dead time

Question 7

Pulse width/leght

Answer 7

it is the lenght of the pulse

Question 8

beam

Answer 8

angular dimension of the radiation pattern

Question 9

Azimuth resolution

Answer 9

is depend of the full beamwidth, separate 2 object in distance seem only one

Question 10

Long range radar

Answer 10

300-200 NM 600 MHz

Question 11

Terminal area

Answer 11

R <= 75 NM 1 GHz surveillance close to major airport

Question 12

approach surveillance radar ASR

Answer 12

<= 25 NM 3 GHz
vectoring / non PA/ no GS / controller pass heading
termiante at 2 NM

Question 13

precision approach radar PAR

Answer 13

<= 10 nm 10 GHz

separation radar GS/azimuth, precision approach, pass heading ranges

Question 14

surface movement

Answer 14

<= 5 NM 15 GHz SHF
narrow beam / high rpm / high PRF /short pulse / short range
60 rpm

Question 15

characteristics

Answer 15

long range require high power
long wavelenght less power
beam width aerial dimension larger aerial can produce narrow beam BW= 70 * lambda/ antenna diameter
short range require short lambda
weather penetration better with longer lambda
Wx clutter noise by weather

Question 16

Weather radar

Answer 16

can detect severe weather, but no possible CAT

ground mapping

Question 17

W Radar Freq

Answer 17

if too low penetrate weather
if too high can detect moisture
perfect around 3 cm of wavelenght 10 GHz reflect large droplet
no reflection from no hazardous clouds

Question 18

tilt

Answer 18

vertical movement of the radar
stab on weep horizontal
stab off sweep parallel to the a/p longitudine
antenna can be tilted +- 15°

Question 19

AGC

Answer 19

to adjust the sensibility of the receiver in a way you can detect also the distance cloud
reduce gain as range decrease

Question 20

WR Modes

Answer 20

WX
man conical beam/ manual gain from 50/60 NM
MAP max range 60/70 NM fan shape bem cosec^2 increase power with increase of range

Question 21

MTI

Answer 21

Moving target indicator - remove static target

Question 22

cloud base

Answer 22

(tilt - beam/2 6080NM)/60