"What is Electronic Intelligence (ELINT)? ELINT is information derived primarily from electronic signals that do not contain speech or text (which are considered COMINT)[Communications Intelligence]. It is divided into major branches. One branch is Technical ELINT (TechELINT), which describes the signal structure, emission characteristics, modes of operation, emitter functions, and weapons systems associations of such emitters as radars, beacons, jammers, and navigational signals. A main purpose of TechELINT is to obtain signal parameters which can define the capabilities and the role that the emitter plays in the larger system, such as a ground radar locating aircraft, and thus lead to the design of radar detection, countermeasure, or counterweapons equipment. The overall process, including operation of the countermeasures, is part of electronic warfare. Another major branch is Operational ELINT (OpELINT), which concentrates on locating specific ELINT targets and determining the operational patterns of the systems. These results are commonly called Electronic Order of Battle (EOB). OpELINT also provides threat assessments, often referred to as 'tactical ELINT.' OpELINT intelligence products support military operational planners and tactical military commanders on the battlefield. A former third major branch of ELINT is the collection, processing, and reporting of foreign telemetry signals intelligence (TELINT). TELINT is technical and intelligence information derived from the intercept, processing, and analysis of foreign telemetry. At one time Telemetry Intelligence was considered a branch of ELINT since TELINT (later to be called FISINT - Foreign Instrumentation Signals Intelligence) activities are closely related to TechELINT procedures and were conducted by all of the Department of Defense (DoD) military departments. TELINT is a critical source of performance information on foreign missiles and space vehicles while they are being developed and tested. TELINT can also provide much operational information on foreign satellites and space vehicles."
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