Proposed Optimization Technique for Complementary Frequency Selective Surface
Frequency Selective surfaces; FSS; Complementary frequency selective surfaces; CFSS; ECM; Equivalent circuit model; Optimization
Frequency selective control of electromagnetic wave flow in certain directions makes Frequency Selective Surface (FSS) a continuous object of study by applied electromagnetism scientists. With a wide range of applications in a wide range of engineering fields, FSS can be used as a tool for improving antenna efficiency in communications systems, as well as for detecting faults in concrete structures such as bridge pillars and many other applications. which will be exemplified later. One particular class of FSSs is the Complementary Frequency Selective Surface (CFSS) which has very interesting features together such as high angular stability, the possibility of multiple transmission and / or reflection bands and miniaturization. The analysis and design of this type of structure is commonly performed using commercial software that implements the so-called full wave method (FWM) which, despite having efficient and reliable responses, require license to use and demand a high effort. computational, impacting a longer time to obtain results. The Equivalent Circuit Model (ECM) provides approximate equations that, by calculating impedances related to the unit cell geometry, model the behavior of a frequency domain FSS faster due to the simplicity of the formulas that can be implemented in free software in many different programming languages, showing good agreement when compared to full wave methods. This research aims to optimize the ECM when applied to complementary frequency selective surfaces, including its use in parallel with techniques from transmission line theory. As part of this study, unpublished modeling in the ECM literature for aperture type geometries, such as the single and double circular loop, will later be proposed as case studies in the implementation of the optimized CFSS equivalent circuit model.