Dictionary of Radar Terms
"A",
"B",
"C",
"D",
"E",
"F",
"G",
"H",
"I",
"J",
"K",
"L",
"M",
"N",
"O",
"P",
"Q",
"R",
"S",
"T",
"U",
"V",
"W",
"X",
"Y",
"Z"
'Ba' to 'Beac', 'Beam' to 'Bz'
Beam: Refer to Lobe antenna.
BEAM, DIVERGENCE: Of an electromagnetic beam, in any plane that intersects the beam axis, the increase
in beam diameter with distance from the aperture from which the beam emerges.
BEAM-STEERING: Changing the direction of the main lobe of a radiation pattern. Note: In radio systems,
beam steering may be accomplished by switching antenna elements or by changing the relative phases
of the rf signals driving the elements.
BEAM-TO-BEAM CORRELATION: [BBC] used by frequency scan radars to reject pulse jamming and jamming at a swept frequency. Correlation is made from two adjacent beams (pulses). The receiver rejects those targets (signals) that do not occur at the same place in two adjacent beams.
BEAMWIDTH: In the radio regime, of an antenna
pattern, the angle between the half-power (3-dB) points of the main lobe, when referenced to the peak
effective radiated power of the main lobe. See Antenna Beamwidth.
BEARING RESOLUTION: The ability of a radar to distinguish between targets that are close together in
bearing.
Beat Frequencies: Difference and sum frequencies which result from combining two different
frequencies.
Beat Frequency Oscillator: [BFO] Any oscillator whose output is intended to be mixed with another
signal to produce a sum or difference beat frequency. Used particularly in reception of CW transmissions.
Bipolar Video: Unrectified (pre-detection) IF (both positive and negative portions of the RF envelope) signals that arise from the type of detection and console display employed in pulse Doppler and MTI receivers.
Bistatic Radar: A radar using antennas at different locations for transmission and reception.
Blackbody: A totally absorbing body that does not reflect radiation.
Blanking: In graphic display, the suppression of the display of one or more display elements or display segments. The process of making a channel, or device non-effective for a certain interval. Used for retrace sweeps on CRTs or to mask unwanted signals such as blanking ones own radar from the onboard RWR.
Blocking: A condition in an amplifier, caused by over-driving one or more stages, in which the
amplifier is insensitive to small signals immediately after reception of a large signal.
Boresight: The physical axis of a directional antenna. To align a directional antenna, using either an optical procedure or a fixed target at a known location [Bore Sighting].
Broadside Array: An antenna array in which the direction of maximum radiation is
perpendicular to the plane of the array.
Burn-Through Range: The ability of a radar to see through jamming. Usually, described as the point when the radar's target return is a specified amount stronger than the jamming signal.
Burst: In data communications, a sequence of signals, noise, or interference counted as a unit in accordance with some specific criterion or measure.
