Efficient Solution of Wideband Partial Modification Problem via Wideband Sherman–Morrison– Woodbury Algorithm

In this letter, an efficient solution of the wideband partial modification problem involving an original structure with small geometric modifications is proposed. Compared with the conventional partial modification analysis method, the proposed method is more efficient in two aspects: first, the inverse of the impedance matrix of the original structure is solved implicitly in a compressed form. Based on the compressed inverses, all the subsequent modification problems can be quickly solved with the aid of the Sherman–Morrison–Woodbury formula and the partitioned-inverse formula each time the modification takes place. Second, solutions of the original structure at different frequencies are related by the adaptive cross approximation and thus can be quickly solved. Numerical examples are performed to demonstrate the accuracy and efficiency of the proposed method.