BLOCKINGA condition in an amplifier, caused by overdriving one or more stages, in which the
amplifier is insensitive to small signals immediately after reception of a large signal.
BROADSIDE ARRAYAn antenna array in which the direction of maximum radiation is
perpendicular to the plane of the array.
BUFFER AMPLIFIER STAGEAmplifier stage that isolates one circuit from another.
CARRIER FREQUENCYThe frequency of an unmodulated transmitter output.
CARRIER-CONTROLLED APPROACHShipboard radar system used to guide aircraft to safe
landings in poor visibility conditions.
CLUTTERConfusing, unwanted echoes that interfere with the observation of desired signals on a
COHERENCEA definite phase relationship between two energy waves, such as transmitted frequency
and reference frequency.
COHERENT OSCILLATORIn cw radar this oscillator supplies phase references to provide coherent
video from target returns.
CONICAL SCANNINGScanning in which the movement of the beam describes a cone, the axis of
which coincides with that of the reflector.
CONTACTIn radar, an object that reflects rf energy; target.
CORNER REFLECTORTwo flat reflectors that meet at an angle and are normally fed by a half-wave
CROSSED-FIELD AMPLIFIERHigh-power electron tube that converts dc to microwave power by a
combination of crossed electric and magnetic fields.
CYLINDRICAL PARABOLIC REFLECTORA parabolically shaped reflector that resembles part
of a cylinder.
DEFLECTION COILSIn a cathode-ray tube, coils used to bend an electron beam a desired amount.
DEIONIZATION TIMEIn a spark gap, the time required for ionized gas to return to its neutral state
after the spark is removed.
DESIGNATIONOperational phase of a fire- control or track radar during which the radar is directed
to the general direction of a desired target.
DIFFERENCE FREQUENCYSee Beat Frequency.
DIODE DETECTORA demodulator that uses one or more diodes to provide a rectified output with an
average value that is proportional to the original modulation.
DIRECTIONAL ANTENNAAn antenna that radiates most effectively in only one direction.
DIRECTIVITYAbility of an antenna to radiate or receive more energy in some directions than in
others. The degree of sharpness of the antenna beam.