In 1887 the German physicist Heinrich Hertz discovered electromagnetic waves and demonstrated that they share the same properties as light waves. These electromagnetic waves are often known as “Hertzian waves.”
In the very early 1900s, Telsa in the US and Hülsmeyer in Germany proposed detection of targets by the use of radio waves.The principle behind RADAR (Radio Detection And Ranging), based on the propagation of electromagnetic waves or, more precisely, that of radiofrequency (RF) waves, was described by the American Hugo Gernsback in 1911. In 1934 the French scientist Pierre David successfully used radar for
the first time to detect aircraft. In 1935 Maurice Ponte and Henri Gutton, during trials carried out onboard the Orégon, part of the Compagnie Générale Transatlantique fleet, detected icebergs using waves with a 16 cm
wavelength (λ). In 1936 Professor Kunhold (Germany) detected aircraft. Radar came into its own during the Second World War as the ideal technique for detecting the enemy, both day and night. As early as 1940 the
British RAF, led by Watson Watt, developed a dense network of groundbased radars. This clinched their victory in the Battle of Britain, as it provided sufficient warning to deploy fighter planes under optimum
conditions. The German army also set up its own ground-based radar network, which, from 1942 onward, they used to transmit the position of detected targets to the fighter control center. In order to intercept and shoot down the waves of allied bombers deployed at night, German fighter pilots used either daytime fighters to attack allied planes tracked by light from ground projectors, or night fighters equipped with radar.
The first ever operational warplane equipped with an airborne radar was the Messerschmitt Me 110 G-4 in 1941. Its Telefunken radar, the FUG 212, used a bulky antenna comprising a number of dipoles located outside the aircraft, on the nose. By June 1944 the German fighter unit possessed over 400 aircraft of this type with a radar range of approximately 5 km, this range being limited by the altitude at which the carrier was flying.By 1944 the American Naval Air Service was equipped with a Corsair with a radar pod on the right wing, while the American Air Force had a Northrop P-61A Black Widow fitted with a Western Electric radar system. During the night of July 24–25, 1943, 800 RAF bombers carried out a raid on Hamburg. During this raid the bombers carried out the first ever operational chaff launch (metal strips whose dimensions vary depending on the wavelength of the radar they attempt to confuse). This operation rendered German ground-based and airborne radars totally nonoperational,blinded by an excess of objects to detect. It marked the beginning of electronic warfare.Radar operators noted that the British Mosquito fighter planes and the
Japanese Zero fighter planes, both wooden constructions, were particularly difficult to detect; they were the original stealth aircraft.In 1943 Allied surface ships fitted with radar were used to detect German submarine snorkels, causing the German navy to suffer heavy losses.Later the main steps in radar technological evolutions were • pulse compression (in the early ‘60s) • pulse Doppler radar (late ‘60s) • digital radars (‘70s) • medium PRF radar (late ‘70s, early ‘80s) • multimode programmable radar (mid-‘80s)
• airborne electronically scanned antenna radar (‘90s) The first radar images of the Earth were obtained in 1978 using Synthetic Aperture Radar (SAR), operating in the L-band (λ ≈ 30 cm) and mounted on
the American satellite Seasat. Resolution of the images obtained, both day and night, was close to 25 m.
In the very early 1900s, Telsa in the US and Hülsmeyer in Germany proposed detection of targets by the use of radio waves.The principle behind RADAR (Radio Detection And Ranging), based on the propagation of electromagnetic waves or, more precisely, that of radiofrequency (RF) waves, was described by the American Hugo Gernsback in 1911. In 1934 the French scientist Pierre David successfully used radar for
the first time to detect aircraft. In 1935 Maurice Ponte and Henri Gutton, during trials carried out onboard the Orégon, part of the Compagnie Générale Transatlantique fleet, detected icebergs using waves with a 16 cm
wavelength (λ). In 1936 Professor Kunhold (Germany) detected aircraft. Radar came into its own during the Second World War as the ideal technique for detecting the enemy, both day and night. As early as 1940 the
British RAF, led by Watson Watt, developed a dense network of groundbased radars. This clinched their victory in the Battle of Britain, as it provided sufficient warning to deploy fighter planes under optimum
conditions. The German army also set up its own ground-based radar network, which, from 1942 onward, they used to transmit the position of detected targets to the fighter control center. In order to intercept and shoot down the waves of allied bombers deployed at night, German fighter pilots used either daytime fighters to attack allied planes tracked by light from ground projectors, or night fighters equipped with radar.
The first ever operational warplane equipped with an airborne radar was the Messerschmitt Me 110 G-4 in 1941. Its Telefunken radar, the FUG 212, used a bulky antenna comprising a number of dipoles located outside the aircraft, on the nose. By June 1944 the German fighter unit possessed over 400 aircraft of this type with a radar range of approximately 5 km, this range being limited by the altitude at which the carrier was flying.By 1944 the American Naval Air Service was equipped with a Corsair with a radar pod on the right wing, while the American Air Force had a Northrop P-61A Black Widow fitted with a Western Electric radar system. During the night of July 24–25, 1943, 800 RAF bombers carried out a raid on Hamburg. During this raid the bombers carried out the first ever operational chaff launch (metal strips whose dimensions vary depending on the wavelength of the radar they attempt to confuse). This operation rendered German ground-based and airborne radars totally nonoperational,blinded by an excess of objects to detect. It marked the beginning of electronic warfare.Radar operators noted that the British Mosquito fighter planes and the
Japanese Zero fighter planes, both wooden constructions, were particularly difficult to detect; they were the original stealth aircraft.In 1943 Allied surface ships fitted with radar were used to detect German submarine snorkels, causing the German navy to suffer heavy losses.Later the main steps in radar technological evolutions were • pulse compression (in the early ‘60s) • pulse Doppler radar (late ‘60s) • digital radars (‘70s) • medium PRF radar (late ‘70s, early ‘80s) • multimode programmable radar (mid-‘80s)
• airborne electronically scanned antenna radar (‘90s) The first radar images of the Earth were obtained in 1978 using Synthetic Aperture Radar (SAR), operating in the L-band (λ ≈ 30 cm) and mounted on
the American satellite Seasat. Resolution of the images obtained, both day and night, was close to 25 m.