Editing Radio navigation (section)

===Lorenz===
{{Main|Lorenz beam}}
In the post-World War I era, the Lorenz company of Germany developed a means of projecting two narrow radio signals with a slight overlap in the center. By broadcasting different audio signals in the two beams, the receiver could position themselves very accurately down the centreline by listening to the signal in their headphones. The system was accurate to less than a degree in some forms.{{fact|date=July 2022}}

Originally known as "Ultrakurzwellen-Landefunkfeuer" (LFF), or simply "Leitstrahl" (guiding beam), little money was available to develop a network of stations. The first widespread radio navigation network, using Low and Medium Frequencies, was instead led by the US (see LFF, below). Development was restarted in Germany in the 1930s as a short-range system deployed at airports as a [[Instrument approach|blind landing]] aid. Although there was some interest in deploying a medium-range system like the US LFF, deployment had not yet started when the beam system was combined with the Orfordness timing concepts to produce the highly accurate [[Sonne (navigation)|Sonne]] system. In all of these roles, the system was generically known simply as a "Lorenz beam".  Lorenz was an early predecessor to the modern [[Instrument Landing System]].{{fact|date=July 2022}}

In the immediate pre-World War II era the same concept was also developed as a blind-bombing system. This used very large antennas to provide the required accuracy at long distances (over England), and very powerful transmitters. Two such beams were used, crossing over the target to triangulate it. Bombers would enter one of the beams and use it for guidance until they heard the second one in a second radio receiver, using that signal to time the dropping of their bombs. The system was highly accurate, and the '[[Battle of the Beams]]' broke out when [[United Kingdom]] [[intelligence service]]s attempted, and then succeeded, in rendering the system useless through [[electronic warfare]].{{fact|date=July 2022}}