Pyramidal Microwave Radiator with Curvilinear Envelope

Considered in this paper is minimization of pyramidal type horn radiator (HR) length at the given reflection factor and the factor of basic wave transformation into waves of the superior types. Minimization is carried out using the method of radiator envelope shape synthesis. Functions determining HR envelope shape at which its length possesses minimal value without changing the given reflection factor (RF) and the factor of basic wave transformation into the waves of the superior types (TF) have been obtained. Using CAD method HR envelope profiles with horn opening cross section 23times10 mm and horn mouth cross section 80times34,8 mm for the wave lengths from lambda_min= 2,4 cm to lambda_min=3,6 cm at target values RF=0,07 and TF=0,03 have been determined. The HR simulated in this way has smaller length compared with HR with rectilinear envelope provided the same RF and TF values. The method proposed allows operating HR key parameters. By putting together curvilinear envelopes of different shapes it is possible to achieve simultaneous reduction of HR RF and TF. The results obtained can be used, for example, at design of SHF mirror antennas irradiators with increased requirements to the orientation diagram, efficiency and overall dimensions.