Electronic Countermeasure - History

History

One of the first examples of electronic countermeasures being applied in a combat situation took place during the Russo-Japanese war. On April 15, 1904, Russian wireless telegraphy stations installed in the Port Arthur fortress and on board Russian light cruisers successfully interrupted wireless communication between a group of 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. Germany and Great Britain interfered with enemy communications along the western front during World War I while the Royal Navy tried to intercept German naval radio transmissions. There were also efforts at sending false radio signals, 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. German bomber aircraft navigated using radio signals transmitted from ground stations, which the British disrupted with spoofed signals in the Battle of the Beams. During the RAF's night attacks on Germany the extent of electronic countermeasures was much expanded, and a specialised organisation, No. 100 Group RAF, was formed to counter the increasing German night fighter force and radar defences. Cold War developments included anti-radiation missiles designed to home in on enemy radar transmitters.