The term 'meacon' is a portmanteau word from 'masking beacon' or 'misleading beacon'. It was a technique extensively developed during World War II.

Meaconing is the interception and rebroadcast of navigation signals. These signals are rebroadcast on the received frequency, typically, with power higher than the original signal, to confuse enemy navigation. Consequently, aircraft or ground stations are given inaccurate bearings.

Successful meaconing can cause aircraft to be lured into 'hot' (ambush-ready) landing zones or enemy airspace, ships to be diverted from their intended routes, bombers to expend ordnance on false targets, or ground stations to receive inaccurate bearings or position locations.

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