D.V. Denisenko1, V.V. Radchenko2

1,2 JSC “CNIRTI named after academician A.I. Berg” (Moscow, Russia)

1 dima_den@inbox.ru; 2 optimizer@mail.ru

Microwave devices on planar transmission lines are difficult to model and require significant time to design. Optimizing the parameters requires calculating thousands of variants with high accuracy, and the time spent on electromagnetic analysis of each variant can be counted in tens of minutes or hours. The challenge of balancing accuracy and speed in modeling remains, for which approximate models and methods are used. Models based on quasi-static approximations allow significant reductions in time, but their simple implementation has acceptable accuracy only for a limited range of problems. More universal approaches based on Green's functions and electromagnetic methods also lead to increased computational costs. In this paper, we propose and investigate a method to improve the computational time for multimode Z-parameter matrices in a class of quasi-static two-dimensional planar element models that provide the ability to model arbitrary topologies of planar microwave devices. Instead of using segmentation techniques, we use the nodal potential method to form a system of equations for a given topology. We calculate matrices of small dimensions and copy matrices of identical segments, which leads to significant savings in numerical time at the expense of a slight increase in the size of the final system of linear equations for the entire network. Numerical experiments were carried out with the help of self-development software written in C/C++ programming languages. We used BLAS and LAPACK libraries of the OneAPI standard for matrix operations and to solve system of linear equations, TBB for parallelization. According to the results of numerical experiments comparative estimations of time costs for computing of multimode matrices for different models of microstrip lines and microstrip filter using typical and proposed approaches are given. It is shown that the proposed method using the segmentation with basic identical segments allows to reduce the time cost of computing the matrices of two-dimensional planar models based on an equivalent resonator with a large number of interconnects (more than 100) by at least 1-2 orders and more depending on the topology. Accordingly, it reduces the total computing time of the S-parameters of the simulated devices.

Denisenko D.V., Radchenko V.V. Fast analysis of multiport planar microwave circuits based on segmentation with base elements.
Radiotekhnika. 2024. V. 88. № 8. P. 170−179. DOI: https://doi.org/10.18127/j00338486-202408-17 (In Russian)

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