In this work, a high performance double layer microwave absorbing structure for X-Ku band was designed and implemented. Genetic-algorithm (GA) was used to find the optimized thickness and type of material for each layer. | Nguyễn Trần Hà và Đtg Tạp chí KHOA HỌC & CÔNG NGHỆ 190(14): 111 - 117 OPTIMAL DESIGN FOR HIGH ABSORPTION OF MICROWAVE IN X-KU BANDS WITH DOUBLE-LAYER STRUCTURE USING GENETIC ALGORITHM Nguyen Tran Ha, Tran Quang Dat, Dang Hai Ninh, Nguyen Vu Tung, Pham Van Thin * Le Quy Don Technical University ABSTRACT In this work, a high performance double layer microwave absorbing structure for X-Ku band was designed and implemented. Genetic-algorithm (GA) was used to find the optimized thickness and type of material for each layer. Tabulated permittivity and permeability of the magneto-dielectric composite materials and silicon rubber were used in the simulation. Angular dependence of the reflection coefficients for TE and TM modes were evaluated. The simulated results were in good agreement with the experimental data collected from three samples. It showed that reflection coefficients of the double layer samples reached up to − dB, − dB and − dB at 10 GHz, GHz and GHz respectively in the case of normal incidence. Keywords: RAM, genetic algorithm (GA), microwave absorbing materials, optimized design, XKu bands INTRODUCTION* Because the mobile technology has developed quickly, electromagnetic interference (EMI) pollution has become a very serious threat to the daily life of human beings. As an effective solution to EMI, radar absorbing materials (RAM) have received increasing attention. For an ideal layer of RAM, thin thickness and broadband absorption are two of the key properties [1-3]. In addition, in recent years, multilayer broadband absorbers have been considered in many civic and military engineering applications, especially, for the design of microwave shielding enclosures, anechoic chambers to ensure electromagnetic compatibility (EMC), wireless telecommunication systems and stealth technology as radar-absorbing material (RAM) [4]. Designing of radar absorbing structure is a great importance over selective or wideband frequency either by .
