Faster Optimization of Quadruple-Ridged Flared Horns Using Geometric Feasibility Parameters

The design of a quadruple-ridged flared horn (QRFH) is onerous due to the large geometric (or optimisation) parameter space that defines the shape of the horn, and the lengthy computation times in evaluating the horn’s performance. The QRFH typically performs over a very wide frequency range, and over this range, it needs to be finely evaluated to ensure that no unwanted frequency aberrations or trapped modes occur. The electromagnetic (EM) computation times are large not only in determining the horn’s performance but also in evaluating the horn’s performance on a reflector system, which is typically electrically large, as would generally be the case for radio astronomy receivers. The primary performance metric for the system is receiving sensitivity or G/T, which requires that the antenna temperature be calculated from the reflector system radiation pattern on a finely sampled full sphere. This is, of course, computationally very expensive on electrically large systems, but accurate approximation techniques exist [1].