Performance Comparison of Stepped and Smooth Dielectric Lens-Loaded Flat Reflectors

Abstract

This paper presents the design of an X-band stepped lens-loaded flat reflector (STLR) using reflectarray unit cell approach. A flat reflector of size 15 × 15 cm 2 , loaded with a 10 × 10 dielectric unit cell array, centre-fed by a horn antenna, is evaluated by simulation and measurement. The simulated performance of the proposed structure is compared with a smooth lens loaded plane reflector (SMLR) and microstrip reflectarray (RA), of equivalent cross section. The results are in good agreement for SMLR, whereas a fair match is observed only in the main lobes of RA. It is worth to note that the reported STLR has a reduced thickness compared to SMLR. Furthermore, a simulation-based study is carried out on the effect of tapering of the dielectric structure in the proposed design, and a similar performance to when stepping is used is noted.