Radar terms, and definitions

Backscattering: Radio wave propagation in which the direction of the incident and scattered waves, resolved along a reference direction (usually horizontal) are oppositely directed. A signal received by backscattering is often referred to as backscatter. In optics, the scattering of light into a direction generally opposite to the original one.

Backward Wave Oscillator: [BWO] A cross-field device in which an electron stream interacts with a backward wave on a non-reentrant circuit. This oscillator may be electronically tuned over a wide range of frequencies, is relatively unaffected by load variations and is stable.

Balanced Mixer: The two most frequently encountered mixer types are single-balanced and double-balanced. In a double-balanced mixer, four Schottky diodes and two wideband transformers are employed to provide isolation of all three ports. A Waveguide arrangement that resembles a T and uses crystals for coupling the output to a balanced transformer. RF Mixer Manufacturers

Bandpass Filter: A type of frequency discrimination network designed to pass a band or range of frequencies and produce attenuation to all other frequencies outside of the pass region. The upper and lower frequencies are usually specified to be the half power (-3dB) or half voltage points (-6dB).

Bands [Frequency]: [Radar Bands]

Bandwidth: An expression used to define the actual operational frequency range of a receiver when it is tuned to a certain frequency. For a radar receiver, it is the difference between the two frequencies at which the receiver response is reduced to some fraction of its maximum response (such as 3 dB, 6 dB, or some other specified level). The frequencies between which "satisfactory" performance is achieved.

Barker Codes: Binary codes used in pulse compression.

Barrage Noise Jamming: Noise jamming spread in frequency to deny the use of multiple radar frequencies to effectively deny range information. Although this is attractive because it enables one jammer to simultaneously jam several radars of different frequencies, it does have the inherent problem that the wider the jamming spread, the less jamming power available per radar, i.e. the watts per MHz bandwidth is low.

Bayonet Connector: See Definition of Bayonet Connector.

Beacon: A system wherein a transponder in a missile receives coded signals from a shipboard radar guidance transmitter and transmits reply signals to a shipboard radar beacon receiver to enable a computer to determine missile position. The missile beacon transmitter and shipboard radar beacon receiver are tuned to a frequency different from that of the guidance transmitter.