Analysis of Oversized Electrodynamic Systems by a Combined Method Based on the Principle of Physical Optics and the Multilevel Fast Multipole Algorithm.

The multilevel fast multipole algorithm (MLFMA) is often used to speed up the solution of surface integral equations in electromagnetics. The method makes it possible to calculate electrodynamic systems with characteristic sizes of hundreds of wavelengths on a personal computer in a relatively short time (a few hours). The paper demonstrates the use of the MLFMA together with the principle of physical optics for fast calculation of microwave radiation between the elements of the mirror transmission lines. The complexity of the calculation is O(NlogN), where N is the number of elementary parts of the mirror surfaces involved in the calculation. Thus, the calculation time for a transmission line with characteristic total mirror sizes of hundreds of wavelengths is a few minutes. By using this method, it is also possible to significantly speed up the calculation of fields in oversized transmission lines, including both waveguides and mirrors, without loss of accuracy. [ABSTRACT FROM AUTHOR]