With the availability of unmanned aerial systems (UAS) such as octocopters a new versatile platform for signal-in-space measurements is deployable. This paper describes concept and design of an octocopter and its instrumentation, being used to investigate the possible interaction of terrestrial navigation systems such as DVORs and radars with single wind turbines (WT) or wind power plants.

In this paper we discuss the results of an intercomparison for free space antenna factor measurements. Three different types of antennas covering the frequency range from 30 MHz to 26.5 GHz have been calibrated in five different laboratories using different methods and calibration sites. The results agree well within the uncertainties specified by the laboratories suggesting that different approaches and different measurement sites to obtain the free space antenna factor are well compatible.

In this paper the electromagnetic field distortion of a DVOR surveillance navigation system in presence of a wind turbine (WT) is investigated as a function of wind direction and rotor position. Therefor regularities of the distortion behavior were determined by 2040 simulations. Based on the calculated data a method is developed which allows to approximate the worst case distortion with the results of only two simplified simulations, which significantly reduces simulation effort.

This paper suggests the design of two ultra-wideband antennas for the application of transient field measurements that are characterized by frequency spectra in the range from a few MHz to several GHz. The motivation for their design is the excitation of high power transient pulses within highly resonant metallic enclosures. The presented measurement and simulation results reveal that the suggested antennas do achieve satisfactory broadband characteristics and ensure high pulse form fidelity.