An adaptive frequency sweeping algorithm of MoM impedance matrices in full-wave analysis of microstrip patch antennas

In this paper, a study on frequency interpolation algorithms of method of moments (MoM) impedance matrices is discussed in detail, which is successfully applied into the full-wave analysis of a microstrip patch antenna in a relatively wide band. By using Lagrange interpolation scheme in an adaptive system, two interpolating rules are realized and their accuracies are defined by Frobenius norms of the impedance matrices in entire frequency band. A microstrip fed patch antenna is considered to verify the algorithm from 1 to 5 GHz. The numerical results have shown that by selecting the Chebyshev zeros in the frequency band for polynomial interpolation is of high accuracy and the simulation efficiency can be highly elevated simultaneously. Besides, a statistical conclusion on the tradeoff between accuracy and efficiency issue has also been made quantitatively.