ABSTRACT
A microwave absorber for an anechoic chamber operating at RF ranges has been designed to study the effects of each variable on the reflection coefficient S 11 . The observed variables are the absorber shape, the effect of full and partial coating, pyramidal height and base size, number of pyramids, excitation source location, the thickness of the underneath perfect electric conductor (PEC) layer and the electrical properties of the absorber coating. The proposed electromagnetic absorbers are investigated using the high-frequency structure simulator (HFSS). The simulated reflection coefficient S 11 result for each effect is plotted and its average over the entire band is calculated. The RF range from 1–6.5 GHz is considered to achieve better return loss (RL = |S 11 |) ≥ 10 dB. The achieved average S 11 is −26.86 dB. These absorbers are a necessity in conducting experiments related to antennas to measure their characteristics, especially the radiation pattern and gain.
