Wind turbines as distorting scattering objects for radar - Visibility, desensitization and shadowing

This paper is a further continuation of the papers on the earlier IRS-conferences and is related to the ongoing and increased interest and so-called “problem” of wind turbines for different radar. It is a competition between the interests of the renewal energy and the operation of the radar. More and more turbines are installed off-shore and on land and by that come into closer distances to radar. These radar may be ATC-, Air-Defence, marine/harbour- or weather radar. Each of these radar providers claims a certain safety distance in order to maintain its “undistorted operation” - whatever that means. The WT are a very special form of a “clutter object” installed above ground which is stationary at a certain location, but has also moving/rotating parts in case of wind. The static responses are well known to most of the modern radar to be suppressed potentially by the MTI in case of primary radar if available. “Clutter” is a radar term which summarizes unwanted effects from natural or man-made objects. Big effort is invested into radar R&D to minimize or suppress the clutter. In case of the WT the location and the principal spectral return is known basically.