Radio Direction Finding
Frank Adcock originally used the antenna as a receiving antenna, to find the azmuthal direction a radio signal was coming from in order to find the location of the radio transmitter; a process called radio direction finding. Prior to Adcock's invention, engineers had been using loop antennas to achieve directional sensitivity. They discovered that due to atmospheric disturbances and reflections, the detected signals included significant components of electromagnetic interference and distortions: horizontally polarized radiation contaminating the signal of interest and reducing the accuracy of the measurement. Adcock—who was serving as an Army officer in the British Expeditionary Force in wartime France at the time he filed his invention—solved this problem by replacing the loop antennas with symmetrically inter-connected pairs of vertical monopole or dipole antennas of equal length. This created the equivalent of square loops, but without their horizontal members, thus eliminating sensitivity to much of the horizontally polarized distortion. The same principles remain valid today, and the Adcock antenna array and its variants are still used for radio direction finding.
Read more about this topic: Adcock Antenna
Famous quotes containing the words radio, direction and/or finding:
“from above, thin squeaks of radio static,
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