ROTATABLE SHORTWAVE CURTAIN ANTENNA OPERABLE AT VERY HIGH WIND SPEEDS

Rotatable shortwave antennas enable broadcasters to cover target areas in any direction. This paper presents the concept and design of a rot atable curtain antenna characterized by a simple and robust design, wh ich can be operated up to very high wind speeds. The deformation of th e steel support structure is shown for typical cases of wind and ice l oading, the results being obtained by FEM calculations. For the very h igh basic wind speed of 41 m/s (92 miles/h) the deflections of the dip ole and reflector curtains are calculated and subsequently the RP char acteristics for this situation. It is found that the influence of wind on the input impedance and the radiation patterns is remarkably low.