Three Radio Direction-Finding Methods

A wide variety of radio direction-finding systems have been developed employing a similar variety of antennas. However, nearly all can be classified into one of three categories according to different underlying operating principles, as follows: 1) Systems based on the directional characteristics of an antenna. 2) Systems based on Doppler shift. 3) Systems based of received amplitude ratios or phase differences between two or more signals transmitted differently. Radio direction-finders in first two categories can be used to find azimuth bearings from receiving locations to transmitting stations. Radio direction-finders in the last category work the other way around in that they find bearings to receiving locations from one or more transmitting stations. ©2005 Tigertek, Inc. All rights reserved.

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