The process of adjusting impedance so that the input impedance of an antenna equals or approximates the characteristic impedance of its transmission line over a specified range of frequencies.
Note: The impedance of either the transmission line, or the antenna, or both, may be adjusted to effect the match.

The temperature of a hypothetical resistor at the input of an ideal noise-free receiver that would generate the same output noise power per unit bandwidth as that at the antenna output at a specified frequency.
Note 1: The antenna noise temperature depends on antenna coupling to all noise sources in its environment as well as on noise generated within the… (Read More →)

Synonym left-hand polarized wave.

Pertaining to equipment, processes, or techniques used to reduce the effect of natural and man-made noise on radio communications.

Measures ensuring that intended transmitted information can be received despite deliberate jamming attempts. [INFOSEC-99]

A point in a standing wave at which the amplitude is a maximum.

1. Measures taken to prevent an unauthorized person/entity from impersonating an authorized person/entity to gain access to a data system. [DoJ]
2. Measures preventing an opponent's participation in an information system (IS). [INFOSEC-99]

A computer program designed to detect computer-file viruses and possibly to suggest or take corrective action. Synonym vaccine program. [After 2382-pt.8]

A thin, dielectric or metallic film, or several such films, applied to an optical surface to reduce its reflectance and thereby increase its transmittance. [After 2196]
Note: For minimum reflection of a normal incident wave of a single wavelength, the antireflection coating may consist of a single layer and must have (a) a refractive index equal to the square root… (Read More →)

ASM uses only the group address to identify the session traffic, noted as (*,G). The group address used must be unique within the network since ASM does not differentiate between (S1,G) and (S2,G) as unique multicast groups.