Blip enhancement is an
electronic warfare
Electronic warfare (EW) is any action involving the use of the electromagnetic spectrum (EM spectrum) or directed energy to control the spectrum, attack an enemy, or impede enemy assaults. The purpose of electronic warfare is to deny the opponen ...
technique used to fool
radar
Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, w ...
. When the radar transmits a burst of energy some of that energy is reflected off a target and is received back at the radar and processed to determine range and angle. The reflected target energy is called skin return, and the amount of energy returning to the originating radar is directly proportional to the
radar cross-section
Radar cross-section (RCS), also called radar signature, is a measure of how detectable an object is by radar. A larger RCS indicates that an object is more easily detected.
An object reflects a limited amount of radar energy back to the source. ...
of the target.
Basic radars present the target information on a display and displayed targets are referred to as blips. Based on the relative size of the blips on the display, a radar operator could determine large targets from small targets. When a blip enhancing technique is used, small targets returns are augmented to look like large targets.
One early maritime application of this technique was used with an
aircraft carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a ...
and its
escort ship
Ocean escort was a type of United States Navy warship. They were an evolution of the World War II destroyer escort types. The ocean escorts were intended as convoy escorts and were designed for mobilization production in wartime or low-cost mass ...
s. Because the aircraft carrier physically dwarfed the other vessels its radar return was much larger making it relatively easy for a radar operator to pick it out as a target. Escort ships were fitted with blip enhance transmitters that received and amplified the radar signal so that all of the escort ships looked like they were aircraft carrier-sized targets. When all the escort ships activated their blip enhance transmitters, all the ships blips grew on the radar display masking the true aircraft carrier blip, and confusing any attempt to target the aircraft carrier for a
missile
In military terminology, a missile is a guided airborne ranged weapon capable of self-propelled flight usually by a jet engine or rocket motor. Missiles are thus also called guided missiles or guided rockets (when a previously unguided rocket i ...
attack.
Electronic countermeasures
Radar
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