MASTER OSCILLATORIn a transmitter, the oscillator that establishes the carrier frequency of the
MECHANICAL SCANNINGThe reflector, its feed source, or the entire antenna is moved in a desired
MINIMUM DISCERNIBLE SIGNAL (MDS)The weakest signal that produces a usable signal at the
output of a receiver. The weaker the signal, the more sensitive the receiver.
MIXERIn radar, a circuit that combines the received rf signal with a local-oscillator signal to
effectively convert the received signal to a lower IF frequency signal.
MODE SHIFTINGIn a magnetron, shifting from one mode to another during a pulse.
MODE SKIPPINGRather than firing on each successive pulse as desired, the magnetron fires
MODESOperational phases (of a radar).
MODULATOR SWITCHING DEVICEControls the on (discharge) and off (charge) time of the
MODULATORProduces a high-voltage pulse that turns the transmitter on and off.
MONOPULSE (SIMULTANEOUS) LOBINGRadar receiving method using two or more (usually
four) partially overlapping lobes. Sum and difference channels locate the target with respect to the
axis of the antenna.
MONOPULSE RADARA radar that gets the range, bearing, and elevation position data of a target
from a single pulse.
MONOPULSE RECEIVERSee Monopulse Lobing.
MOISTURE LAPSEAbnormal variation of moisture content at different altitudes because of high
moisture located just above large bodies of water.
MOVING TARGET INDICATORA device that limits the display of radar information to moving
NAUTICAL MILEThe length of a minute of arc of a great circle of the earth (6,076 ft.)
NAUTICAL RADAR MILESee Radar Mile.
NOISEIn radar, erratic or random deflection or intensity of the indicator sweep that tends to mask
small echo signals.
NOISE FIGUREThe ratio of output noise to input noise in a receiver.
NUTATINGMoving an antenna feed point in a conical pattern so that the polarization of the beam
does not change.
OMNIDIRECTIONAL ANTENNAAn antenna that radiates equally in all directions (nondirectional).
ORANGE-PEEL PARABOLOIDA section of a complete circular paraboloid that is narrow in the
horizontal plane and wide in the vertical plane.