Strategy for reflector pattern calculation: Let the computer do the work

Using high-frequency approximations, the secondary pattern of a reflector antenna can be calculated by numerically evaluating a radiation integralI(u, v). In recent years, tremendous effort has been expended to reducingI(u, v)to Fourier integrals. These reduction schemes are invariably reflector geometry dependent. Hence, different analyses/computer software development must be carried out for different reflector shapes/boundaries. The purpose of this communication is to point out that as the computer power improves, these reduction schemes may not always be necessary. Comparable accuracy and computation time can be achieved by evaluatingI(u, v)by a brute-force fast Fourier transform (FFT) described in this note. Furthermore, there is virtually no restriction on the reflector geometry by using the brute-force FFT.