Terms in this set (38)
Radar surface-angular measurements are referenced to true north and measured in what plane?
The distance from a radar set to a target measured along the line of sight is identified by what term?
What is the speed of electromagnetic energy to traveling through air?
Approximately the speed of light (162,000 nautical miles per second)
In addition to recovery time, what determines the minimum range of a radar set?
Atmospheric interference with the travel of electromagnetic energy increases with what RF energy characteristics?
What type of radar transmitter power is measured over a period of time?
What term is used to describe the product of pulse width and pulse repetition frequency?
PW X PRF = DUTY CYCLE
What type of target bearing is referenced to your ship?
What type of radar detects range, bearing, and height?
What characteristics of radiated energy is (are) altered to achieve electronic scanning?
FREQUENCY OR BASE
What term is used to describe the ability of a radar system to distinguish between targets that are close together?
The degree of bearing resolution for a given radar system to distinguish between targets that are very close to each other?
BEAM WIDTH AND RANGE
What happens to the electromagnetic energy traveling through air as the altitude increases?
What term is used to describe a situation in which atmospheric temperature first increases with the altitude and then begins to decrease?
What radar subsystem supplies timing signals to coordinate the operation of the complete system?
When a transmitter uses a high-power oscillator to produce the output pulse, what switches the oscillator on and off?
HIGH-VOLTAGE PULSE FROM THE MODULATOR
What radar component permits the use of a single antenna for both transmitting and receiving?
What is the simplest type of scanning?
How does the operator of a single lobe scanning system determine when the target moves off the lobe axis?
THE REFECTED SIGNALS DECREASE IN STRENGTH
What are the two basic methods of scanning?
Mechanical and Electronic
Rotation of an RF-feed source to produce a conical scan pattern is identified by what pattern?
The Doppler effect causes a change in what aspect of RF energy that strikes a moving object?
The Doppler variation is directly proportional to what radar contact characteristics?
The Doppler method of object detection is best for what type objects?
The best frequency in a swept frequency transmitter provides what contact information?
What factor determines the difference between the transmitted frequency and the received in an FM system?
What type of objects are most easily detected by an FM system?
What transmission method does not depend on relative frequency or target motion?
What transmission method uses a stable CW reference oscillator, which is locked in phase with the transmitter frequency?
What type of radar provides continuous range, bearing, and elevation data on an object?
Radar altimeters use what type of transmission signal?
A surface search radar normally scans how many degrees of azimuth?
What limits the maximum range of a surface-search radar?
What is the shape of the beam of a surface search radar?
Wide vertically, narrow horizontally
Air search radar is divided into what 2 basic categories?
2D and 3D
What position data are supplied by 2D search radar?
RANGE AND BEARING
Why do 2D air-search radars use relatively low carrier frequencies and low-pulse repetition rates?
INCREASED MAXIMUM RANGE
Why is the capability of 3D radar usually less the range of the 2D radar?