Dual-Polarized Band-Absorptive Frequency-Selective Rasorber With Narrow Transition Band Based on a Multilayer Open Circular Cavity Truncated Cone
Weiliang Yu, Yuchang Chen, Zhen Liao, Wenlei Wang, Leilei Liu, Guo Qing Luo
Abstract
This communication proposes a dual-polarized band-absorptive frequency-selective rasorber (BA FSR) with high selectivity. By layering multilayer open circular cavities (OCC) with a gradient radius, a multilayer OCC truncated cone unit cell is created. The transmission, absorption and dispersion characteristics of the single-layer OCC array, the multilayer OCC array with an equal radius and the proposed multilayer OCC array with a gradient radius are all analyzed in detail. In addition, the operation modes of transmission poles and absorption peaks are investigated. The measured results reveal a decent lowpass band with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert S_{11}\vert \le -10$ </tex-math></inline-formula> dB, a narrow transition band with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$FR_{\mathrm {ap}}$ </tex-math></inline-formula> = 1.06, and a wide absorption band with a fractional bandwidth (FBW) of 65.8% for the prototype. Additionally, it exhibits a stable stealth performance within the ±30° airspace range.