A Low-Cost Structure for Reducing Reflection Loss in Intelligent Reflecting Surface of Liquid Crystal
Yue Cui, Hiroyasu Sato, Yosei Shibata, Takahiro Ishinabe, Hideo Fujikake, Qiang Chen
Abstract
In this letter, a structure to reduce the reflection loss in intelligent reflecting surface of liquid crystal (IRS-LC) is proposed. The loss in IRS-LC is analyzed, indicating that the electric field in the liquid crystal (LC) is a primary cause. To address this issue, a structure by introducing a loss suppression structure beneath the LC layer is presented. Theoretical analysis confirms the low reflection loss characteristic of the structure, and a 15 × 15 prototype IRS-LC array is fabricated and measured. Simulated and measurement results show that the proposed IRS-LC has a maximum reflection loss reduction of 11.3 dB, a magnitude variation reduction of 8.5 dB at 40.3 GHz, and a reflection phase range of 204 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\circ$</tex-math></inline-formula> . The results validates the proposed structure in reducing the reflection loss. Furthermore, the proposed IRS-LC structure has the advantages of low cost and easy processing.