Synthesis of a dielectric rod array for a multiple beam reflector antenna

At the Delft University of Technology a new transportable atmospheric radar (TARA), having a sophisticated antenna system, is under construction. The antenna of TARA has multiple beams pointing in different directions. The beams are switched electronically by means of a parabolic dish fed by a dielectric rod array located in the focal plane. Moumen and Ligthart (1999) showed that an array consisting of two dielectric rods separated by 0.77/spl lambda/, where /spl lambda/ stands for the wavelength, is needed in order to achieve a well focused beam at 15/spl deg/ with low side-lobes. However, due to this small separation distance, degradation of the radiation pattern and mismatches, due to mutual coupling, become a serious problem. This paper presents a method to synthesise the dielectric rod array (amplitude and phase distribution) that takes into account mutual coupling effects.