Researchers have developed a measuring system which, hanging from a helicopter, detects the electric field strength as well as the signal contents of air-traffic control navigation systems. The data could be used in the planning phase of wind farms to find out to what extent the planned wind farms would influence the operation of neighboring radar facilities used for air-traffic control, aerial defense, or meteorological observations. A miniaturized version of the measuring arrangement has already made its first test flights on an octocopter.

The core piece of the technology is an antenna and receiver system. In its previous design, it hangs down from a helicopter and can measure the electromagnetic field strength at any random location in space and save the measured data as well as the exact location (GPS supported by EGNOS) with a very high sampling rate in real time. The system is capable of measuring the electromagnetic far field necessary for a flawless signal transmission (e.g. between an instrument landing system and an aircraft).

The researchers have miniaturized this antenna system to fit it onto an octocopter. On such aerial vehicles, it might soon be possible to use the sensor at places where wind farms already exist or where they are planned in order to acquire data with regard to the field strength and to modified signal contents at any selected coordinates over any random periods. The researchers intend to use it in a first step to metrologically detect the real-time dynamic change in the electromagnetic wave propagation caused by wind farms, to analyze it, and feed it into a (preferably) simple model of the electromagnetic data transmission channel.

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