Comparative Analysis of n-bit LCP-based Terahertz Reflectarray

Abstract

Due to the tunable dielectric constant of liquid crystal polymer (LCP), double dipole LCP-based phase shifter exhibits wide rang phase shift of more than 360° at 0.34 THz. Based on this precondition, a n-bit digital phase shifter concept is proposed. The n-bit (n=1, 2, 3) LCP-based reconfigurable reflectarray (RRA) at 0.34 THz composed of 30×30 elements has been designed and analyzed. The radiation patterns of the RRAfor beam scanning at 15° and 45° are presented. Compared with 1-bit RRA, radiation patterns, such as main lobe direction, gain and side lobe level of the RRA are significantly improved when n=2, 3. However, 2-bit and 3-bit RRAs show similar radiation patterns. Due to 2 bits RRA only needs 4 states, the structure of 2-bit RRA is more simpler, which indicates 2-bit RRA is a low-cost solution to THz beam scanning array.