CH 1: Radar Theory Introduction Flashcards
What does RADAR stand for?
Radio Detection and Ranging
T/F: Can continuous wave transmissions provide range of a target?
False. CW cannot provide range, only provide azimuth information and velocity
Pulse radar can provide range and azimuth and velocity
Radar advantages
- Radar can ‘see’ farther than the human eye
- Radar is all WX/day-night capable, relatively immune to smoke, haze, clouds
Radar Disadvantages
- Radar resolution is significantly degraded compared to EO
- Unable to provide positive identification for targeting
- Susceptible to clutter and undesirable reflections
Radar Target Discriminants
Radar systems must use target discriminants to isolate the desired target return from the clutter
- Range: the time an RF wave takes to go to and return from a target allows measurement of range from radar to target.
- Angle: the angle of a radar return measured relative to true North. The ability of a radar system to determine angle is a function of the horizontal beam width of the antenna.
- Velocity: the frequency shift, called the Doppler effect, allows the measurement of the velocity of that target relative to the radar. The receiver measures this frequency difference which equates to a specific radial velocity.
Basic Pulse Radar System Components
Transmitter sends electromagnetic energy (RF) to the antenna which is radiated through the atmosphere. When the RF energy is interrupted by an object, a portion of the RF energy is reflected back to the antenna and processes by the receiver.
Reflection of radar energy is called a..?
The object interrupting the RF energy is a…?
Echo
Target
The echo from a desired target is called a…?
The echo from an undesired target is called a..?
- target signal
- clutter
The ability of the antenna to focus the RF energy affects what?
angular discrimination of the radar
The ability of the master timer to determine the time between the RF transmission and the target echo reception impacts what?
range determination capability of the radar
The ability of the receiver to analyze the Doppler frequency shift in the target echo determines what?
The velocity determination capability of the radar and the ability of the radar to reject clutter.
Early Warning (EW) radar Characteristics
- Designed to provide attack warning
- high power output
- Large antennas
- Low frequencies
- Limited accuracy on target parameters
Ground Control Intercept Radar Characteristics
-Designed to provide target engagement information: range, azimuth, altitude to vector AI assets to intercept and destroy attacking aircraft.
Early Warning radars paired with height finding radars often referred to as a GCI site
Any radar system that can determine 3D target data can act as a GCI site
Can be used to supplement EW radar systems to provide attack warning
Acquisition Radar Characteristics
-Designed to provide target engagement information for ground based Target Tracking radars (TTRs)
- Shorter range capability and higher frequencies than EW radars
- Provide target range and azimuth data to TTRs
- Can be distinct system or incorporated as part of TTR
Target Tracking Radar Characteristics
-provides continuous and accurate target parameters to a fire control computer
- employ various tracking techniques to update target parameters
- generally employ high frequencies, narrow beam widths, and computer signal processing to enhance accuracy of target parameters
