History of radar

Several inventors, scientists, and engineers contributed to the development of radar. The first to use radio waves to detect "the presence of distant metallic objects via radio waves" was Christian Hülsmeyer,[2][3] who in 1904 demonstrated the feasibility of detecting the presence of a ship in dense fog, but not its distance. He received Reichspatent Nr. 165546 for his pre-radar device in April, and patent 169154 on November 11 for a related amendment. He also received a patent (GB13170) in England for his telemobiloscope on September 22, 1904.[2][4]

Nikola Tesla, in August 1917, first established principles regarding frequency and power level for the first primitive radar units[citation needed]. Before the Second World War, developments by the Americans (Dr. Robert M. Page tested the first monopulse radar in 1934),[5] the Germans, the French (French Patent n° 788795 in 1934),[6] and mainly the British who were the first to fully exploit it as a defence against aircraft attack (British Patent GB593017 by Robert Watson-Watt in 1935),[6][7] led to the first real radars. Hungarian Zoltán Bay produced a working model by 1936 at the Tungsram laboratory in the same vein.In 1934, Émile Girardeau, working with the first French radar systems, stated he was building radarsystems "conceived according to the principles stated by Tesla". [1]

The war precipitated research to find better resolution, more portability and more features for the new defence technology. Post-war years have seen the use of radar in fields as diverse as air traffic control, weather monitoring, astrometry and road speed control.

This long-range radar antenna, known as ALTAIR, is used to detect and track space objects in conjunction with ABM testing at the Ronald Reagan Test Site on the Kwajalein atoll.[1]

Radar is a system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain. A transmitter emits radio waves, which are reflected by the target and detected by a receiver, typically in the same location as the transmitter. Although the radio signal returned is usually very weak, radio signals can easily be amplified. This enables a radar to detect objects at ranges where other emissions, such as sound or visible light, would be too weak to detect. Radar is used in many contexts, including meteorological detection of precipitation, air traffic control, police detection of speeding traffic, and by the military. It was originally called RDF (Radio Direction Finder) in Britain. The term RADAR was coined in 1941 as an acronym for Radio Detection and Ranging. The term has since entered the English language as a standard word, radar, losing the capitalization in the process.