right|thumb|250px|Inspecting an AN/ALQ-184 Electronic Attack Pod.

An electronic countermeasure (ECM) is an electrical or electronic device designed to trick or deceive radar, sonar, or other detection systems, like infrared (IR) or lasers. It may be used offensively and defensively to deny targeting information to an enemy. The system may make many separate targets appear to the enemy, or make the real target appear to disappear or move about randomly. It is used effectively to protect aircraft from guided missiles. Most air forces use ECM to protect their aircraft from attack. It has also been deployed by military ships and recently on some advanced tanks to fool laser/IR guided missiles. It is frequently coupled with stealth advances, so the ECM systems have an easier job. Offensive ECM often takes the form of jamming. Self-protecting (defensive) ECM includes blip enhancement and jamming missile terminal homers.

History

The first example of electronic countermeasures applied in combat occurred during the Russo-Japanese War. On July 13, 1904, Russian wireless telegraphy stations installed in the Port Arthur fortress and on board Russian light cruisers successfully interrupted wireless communication between Japanese battleships. The spark-gap transmitters in the Russian stations generated senseless noise while the Japanese were making attempts to coordinate their efforts in the bombing of a Russian naval base. During World War I, Germany and the United Kingdom interfered with enemy communications along the western front, while the Royal Navy tried to intercept German naval radio transmissions. There were also efforts to send false radio signals, such as having shore stations send transmissions using ships' call signs and jamming enemy radio signals.

World War II ECM expanded to include dropping chaff (originally called Window), jamming and spoofing radar and navigation signals. Israeli electronic warfare (EW) systems took over Syria's air defense systems, feeding them a false sky-picture. At the same time, Israel Air Force jets crossed much of Syria, bombed their targets and returned.

Radar ECM

thumb|Simulated radar screen in US Navy training exercise showing simulated jamming (triangular white area lower right)

Basic radar ECM strategies are (1) radar interference, (2) target modifications, and (3) changing the electrical properties of air. for all-around coverage and retain the capability of highly directional jamming.

DARPA's Precision Electronic Warfare (PREW) project aims to develop a low-cost system capable of synchronizing several simple airborne jamming pods with enough precision to replicate the directionality of an electronically scanned antenna, avoiding collateral jamming of non-targeted receivers.

Selex ES has already developed an expendable active decoy that uses DRFM technology to jam RF-based threats. (merged into Leonardo, the new name of Finmeccanica since 2017). The system, named BriteCloud, is self-contained within a small canister similar to a standard flare cartridge. The 55 mm format of the system has undergone flight trials with the Gripen aircraft, and the development of a 218 variant is at an advanced stage.

Dedicated ECM aircraft

  • EA-3 Skywarrior
  • EB-66 Destroyer
  • EC-130H Compass Call
  • EA-6B Prowler equipped with ALQ-92 communications jammer, ALQ-100 multi-band track breaking system, and five ALQ-99 tactical jammer pods.
  • EA-18G Growler
  • EA-37B Compass Call
  • EF-111A Raven
  • Tornado ECR
  • J-16D
  • Su-24MP
  • Yak-28PP
  • Mi-8PP

Shipboard ECM

The ULQ-6 deception transmitter was one of the earlier shipboard ECM installations.

See also

  • AN/MSR-T4
  • Electronic warfare
  • Electronic warfare support measures
  • Electronic counter-countermeasure
  • Khibiny (electronic countermeasures system)
  • Krasukha (electronic warfare system)
  • No. 100 Group RAF
  • Samyukta electronic warfare system
  • Starshel rounds
  • List of military electronics of the United States

References

Sources

  • Polmar, Norman: "The U. S. Navy Electronic Warfare (Part 2)", United States Naval Institute Proceedings, November 1979.
  • Electronic Counter Measures (PDF) (Lee Pucker)
  • A Down of Electronic Counter Measures- in Russian
  • 100 years of ECM- in Russian