Dra Reflectarray Unit Elements With Thin Under-Loading Parallel Slots

Abstract

This paper presents three dielectric resonator (DR) unit elements loaded with one, two, and three narrow slots underneath for designing reflectarrays. The slots are aligned in parallel, and the lengths are varied to function as phase shifter for changing reflection phase. It is found that the dominant TE mode of the square DR element can be easily excited by placing multiple parallel slots beneath a DR element. Study shows that the number and width of the slots can be used as additional design parameters for tuning the reflection loss and phase range of the reflectarray. Rectangular waveguide method has been deployed, showing reasonable agreement between simulation and measurement. It is found that a reasonable reflection phase range of 313 • with slow slope is obtainable when the DRA is loaded with two slots beneath, which can be used for designing a small-size reflectarray. The reflection characteristics of the unit elements are studied, along with a complete parametric analysis.

Broadrange Reflectarray Element with Combined Slot and Dielectric Resonator Resonances

“…Figure 4(b) depicts the measured and simulated S curves at different R 1 . As can be seen from the figure, there is good agreement between the two, and a reflection phase range of 916° is obtainable, which is much larger than that in [13] loaded with multiple straight slots. Table 1 compares the proposed broadrange reflectarray element with some of the relevant published structures.…”