Electronic Intelligence at NSA

The National Security Agency (NSA) just published the history of Electronic Intelligence (ELINT) at the National Security Agency. ELINT is all information that is obtained from electronic signals, other than speech or text. Within ELINT there are two main branches, Technical and Operational ELINT.

U.S. Air Force Boeing RC-135U ELINT platform

Technical ELINT or TechELINT is the interception and analysis of signals that origin from radars, weapons systems, navigation systems and such, in order to retrieve information on how these systems work, perform and how they are used. TechELINT is useful to determine what technology the opponent applies, the capabilities of his equipment and how to take countermeasures against his systems.

Operational ELINT or OpELINT is focused on the interception of all kinds of signals on specific locations, in order to find out the opponent's location and structure. OpELINT determines the operational structure (order of battle) of the opponent forces, the so-called Electronic Order of Battle (EOB). This, of course, is important to assess his strength and provides vital tactical information on the battlefield.

U.S. Army Beechcraft RC12 GUARDRAIL COMINT & ELINT Platform

The document explains the origins of modern ELINT in the Second World War, and later on the establishing of the Army-Navy Electronics Evaluation Group (ANEEG) within the Department of Defense. NSA eventually took over the ELINT operations in close cooperation with other agencies such as the National Reconnaissance Office (NRO) with its satellites and the Navy aircraft platforms.

NSA published two interesting documents about ELINT.

• Electronic Intelligence (ELINT) at NSA (pdf)
  
• Telemetry Intelligence (TELINT) During the Cold War (pdf).
  

More on Signals Intelligence on this blog and the Cold War Signals page on our website.