Direction findingDirection finding (DF), or radio direction finding (RDF), is - in accordance with International Telecommunication Union (ITU) - defined as radio location that uses the reception of radio waves to determine the direction in which a radio station or an object is located. This can refer to radio or other forms of wireless communication, including radar signals detection and monitoring (ELINT/ESM). By combining the direction information from two or more suitably spaced receivers (or a single mobile receiver), the source of a transmission may be located via triangulation.
Operation Sea LionOperation Sea Lion, also written as Operation Sealion (Unternehmen Seelöwe), was Nazi Germany's code name for their planned invasion of the United Kingdom. It was to have taken place during the Battle of Britain, nine months after the start of the Second World War. Following the Battle of France and that country's capitulation, Adolf Hitler, the German Führer and Supreme Commander of the Armed Forces, hoped the British government would accept his offer to end the war.
Boulogne-sur-MerBoulogne-sur-Mer (bulɔɲ syʁ mɛʁ; Boulonne-su-Mér; Bonen; Gesoriacum or Bononia), often called just Boulogne (UKbʊˈlɔɪn, USbuːˈloʊn,_buːˈlɔɪn), is a coastal city in Northern France. It is a sub-prefecture of the department of Pas-de-Calais. Boulogne lies on the Côte d'Opale, a touristic stretch of French coast on the English Channel between Calais and Normandy, and the most visited location in the region after the Lille conurbation. Boulogne is its department's second-largest city after Calais, and the 183rd-largest in France.
The BlitzThe Blitz was a German bombing campaign against the United Kingdom, in 1940 and 1941, during the Second World War. The term was first used by the British press and originated from the term Blitzkrieg, the German word meaning 'lightning war'. The Germans conducted mass air attacks against industrial targets, towns, and cities, beginning with raids on London towards the end of the Battle of Britain in 1940 (a battle for daylight air superiority between the Luftwaffe and the Royal Air Force over the United Kingdom).
Battle of BritainThe Battle of Britain (die Luftschlacht um England, "the air battle for England") was a military campaign of the Second World War, in which the Royal Air Force (RAF) and the Fleet Air Arm (FAA) of the Royal Navy defended the United Kingdom (UK) against large-scale attacks by Nazi Germany's air force, the Luftwaffe. It was the first major military campaign fought entirely by air forces. The British officially recognise the battle's duration as being from 10 July until 31 October 1940, which overlaps the period of large-scale night attacks known as the Blitz, that lasted from 7 September 1940 to 11 May 1941.
Amphibious warfareAmphibious warfare is a type of offensive military operation that today uses naval ships to project ground and air power onto a hostile or potentially hostile shore at a designated landing beach. Through history the operations were conducted using ship's boats as the primary method of delivering troops to shore. Since the Gallipoli Campaign, specialised watercraft were increasingly designed for landing troops, material and vehicles, including by landing craft and for insertion of commandos, by fast patrol boats, zodiacs (rigid inflatable boats) and from mini-submersibles.
