Pattern Reconfigurability using Plasma for Beamsteering Application at S-band

For the UHF range, a circular plasma antenna array with beam shaping is designed using CST. The simulation results are detailed in paper [1]. This paper presents the experimental results of the fabricated plasma antenna array. In this setup, an omnidirectional metal antenna is positioned at the center of a metal ground that includes plasma reflectors. These plasma reflectors create a plasma blanket around the omnidirectional antenna. When the plasma frequency exceeds the antenna’s operational frequency, the plasma functions perfectly as a reflector; however, when the plasma frequency is lower, it becomes transparent. Turning off the fluorescent lights generates a plasma window, allowing the electromagnetic signal to be scanned 360° by sequentially activating and deactivating these plasma tubes. Consequently, the antenna beam can be electronically steered in any direction within the 360° range, eliminating the need for mechanical steering. The experimental S11 of the plasma antenna array measures -23.58 dB at 2.8 GHz and remains below -10 dB within a frequency band spanning from 2.4 GHz to 3.2 GHz. The experimental front-to-back ratio of the array is 6 dB for plasma windowing.