Multi-Beam Frequency Tunable Antenna based on Plasma-Nested Helix

A frequency tunable antenna supporting multiple beams based on plasma technology is presented in this letter. Key components of the proposed antenna are an axial mode helical antenna and a nested plasma column antenna inside the helix. The antenna has the potential to operate in the frequency range of VHF (200-400 MHz), with a broadside radiation pattern and L band (900-1500 MHz) with an end fire radiation pattern. The proposed structure has the ability to restrict its performance in the only L band frequency range. The radiation characteristics are analyzed and investigated using the finite integral technique.