Radar Princ Flashcards
Differences between primary and secondary
Primary radar is 2 ways energy secondary is 1 way
Primary has no target coop secondary it two radars commin
Primary requires high tx power secondary has a low power tx
Target characteristics that effect radar performance
Type of material
Shape
Size
Distance
Describe clutter
Unwanted returns from anything other than a target
Target info provided by a pulsed primary radar
Slant range
Elevation
Azimuth
Receiver
Selects, amplifies and produces video pulses
T/R switch
Allows a single aerial for Tx and Rx
MTU
Controls the PRF
Modulator
Controls PW
RF oscillator
Controls the radio freq of the pulses
Aerial
Focuses and shapes the RF into a beam
Display
Displays the target echoes
What governs the choice of Freq
Size of target
Max detection range
Size of aerial
Beam width
What governs choice of PRF
Display definition
Aerial scanning speed
Transmitter mean power
Max range
What governs choice of pulse width
Receiver bandwidth
Transmitter mean power
Minimum range
Target discrimination
If the range increase by double how much does does peak power increase by
Increase by 16 time the og
If the range decrease by halve how much does peak power decrease by
1/16th of the power
If power halves what is the % of range
84%
What is second time around echoes and how is it corrected
An echo that has returned from beyond the selected range and appears in a display time of a pulse transmitted later
PRF jittering
What target Info is provided by CW
Velocity
Func of mixer in CW
Produced the Doppler freq
Target info provided by FMCW
Range
Func of freq modulator in FMCW
Changes the Tx freq scanning up and down linearly
