A hypothetical antenna that radiates or receives equally in all directions.
Note: Isotropic antennas do not exist physically but represent convenient reference antennas for expressing directional properties of physical antennas.

Synonym absolute gain.

Internet Service Provider

IPTV Security Solution/Authentication

Information Systems Security Architecture

Information System Security Assurance Architecture

Integrated Services (Digital Network) User Part

Information Technology

ITAR are the regulations covering the exporting of weapons and weapons related technology from the United States. For some strange reason, the government claims that data encryption is a weapon and comes under the ITAR regulations. There is presently a move in Congress to relax the section of ITAR dealing with cryptographic technology.

In electrical circuits, for a four-terminal network, the impedance that, if connected across one pair of terminals, will match the impedance across the other pair of terminals.
Note: The iterative impedance of a uniform line is the same as its characteristic impedance.