How does a VOR determine navigation radials?

A VOR (VHF Omnidirectional Range) determines navigation radials using a method that involves transmitting two overlapping radio signals. One of these signals is a reference signal transmitted in all directions, while the other is a variable signal that rotates 360 degrees around the station. By comparing the phase of these two signals, an aircraft receiver can determine its radial position relative to the VOR station. The result is that the aircraft can determine its bearing to or from the VOR in terms of radial degrees.

This ping/sweep method effectively allows pilots to navigate by flying along these radials to reach various destinations or to track their position in relation to the VOR station. The VOR system is grounded in radio wave technology, and the way it works is fundamental to traditional navigation, especially before the widespread availability of GPS systems. Hence, the method by which VOR determines navigation radials is integral to understanding navigational aids in aviation.