Radar Flashcards
RADAR is an acronym for?
RAdio Detection And Ranging
How is RADAR modulated?
You could have answered with any of the following: 1. Pulse 2. Pulse modulated
What are two chief attributes of RADAR?
Detection at large distances and accurately locating one’s position.
XBand Radar what is the wavelength?
You could have answered with any of the following: 1. 3 cm
XBand Radar what is the frequency band in MHz?
You could have answered with any of the following: 1. 93009500
SBand Radar what is the wavelength?
You could have answered with any of the following: 1. 10 cm
SBand Radar what is the frequency band in MHz?
You could have answered with any of the following: 1. 29003100
Pulse modulated Radar pulses are frequently ____ microsecond or less.
You could have answered with any of the following: 1. one 2. 1
What type of polarization do marine Radars commonly have? 1. Vertical 2. Horizontal
The correct answer is: Number 2 Horizontal
Define frequency.
Number of cycles completed in one second.
The power at points in the beam is _______ proportional to the ______ of the distance 1. directly square 2. inversely square 3. directly cube 4. inversely cube
The correct answer is: Number 2 inversely square
Beam width is measured as the angle between the ______ power points. 1. even 2. squared 3. half 4. quarter
The correct answer is: Number 3 half
Typical horizontal beam width is between ____ and ____ degrees. 1. 1.5 2.0 2. 0.65 2.5 3. 0.65 2.0 4. 1.0 2.5
The correct answer is: Number 3 0.65 2.0
Typical vertical beam width is between ____ and ____ degrees. 1. 10 30 2. 15 30 3. 15 35 4. 20 35
The correct answer is: Number 2 15 30
Narrower beam widths are achieved using ______ wavelengths. 1. Shorter 2. Longer
The correct answer is: Number 1 Shorter
For a given wavelength narrower beam widths are achieved using ______ antennas. 1. Smaller 2. Longer
The correct answer is: Number 2 Longer
At lower frequencies the interference pattern is _____ coarse than at higher frequencies. 1. Less 2. More
The correct answer is: Number 2 More
The pitch and roll of a ship _____ affect the structure of the interference pattern. 1. does 2. does not
The correct answer is: Number 2 does not
The bending of a wave as it passes and obstruction is _______. 1. refraction 2. diffraction
The correct answer is: Number 2 diffraction
The bending of a wave due to atmospheric conditions is _______. 1. refraction 2. diffraction
The correct answer is: Number 1 refraction
Refraction takes place when the ______ of a wave is changed
velocity
Calculation of the radar horizon ignores ______. 1. refraction 2. diffraction
The correct answer is: Number 1 refraction
SUBrefraction occurs in ______ regions and _______ radar range? 1. temperate increases 2. temperate decreases 3. arctic increases 4. arctic decreases
The correct answer is: Number 4 arctic decreases
SUPERrefraction occurs generally in _______ environments and _______ radar range. 1. tropic increases 2. tropic decreases 3. arctic increases 4. arctic decreases
Caused when warm air blows over cool water weather must be calm with little disturbance. The correct answer is: Number 1 tropic increases