Efficient 3-D moment-method analysis for reflector antennas using a far-field approximation technique

A full 3-D moment-method analysis is used to model the radiation patterns o f 10-15 lambda diameter reflector antennas. The moment-method is made compu tationally efficient by a far-field approximation technique which dramatica lly reduces the demands of computer memory and CPU time by over 90% and 80% , respectively. The reflector dishes are discretised with an unstructured 3 -D finite-element-type mesh of triangles. The moment-method is applied to r otationally symmetric dishes in order to compare the accuracy of the analys is with results from a more conventional body-of-revolution type moment-met hod analysis.