Efficient Implementation of BOR FDTD Algorithms in the Engineering Design of Reflector Antennas

This work presents a modelling-based methodology for the design and evaluation of axi-symmetrical antennas, including horns, compact and large dual-reflector antenna systems. The starting concept of the antenna is an educated guess stemming from the engineer's experience; however, further evaluation and optimization of that concept continue in a computational loop that involves a conformal FDTD algorithm in a BOR formulation. Our BOR FDTD retains the advantages of general-purpose 3D FDTD software, providing full-wave solutions and delivering key engineering parameters of antenna systems together with an insight into the distribution of the electromagnetic near-field, a useful feature to assess the mismatch of the horn due to the subreflector interaction. At the same time, the unique BOR formulation accelerates the analysis by orders in magnitude, making it practical to evaluate many designs within a manual or automatic optimization loop. We also show that BOR FDTD compares favourably with the Mode Matching Technique, being computationally fast while obviating the MMT inherent structural assumptions.