Reconfigurable Plasma Antenna Array by Using Fluorescent Tube for Wi-Fi Application

This paper presents a new design of reconfigurable plasma antenna array using commercial fluorescent tube. A round shape reconfigurable plasma antenna array is proposed to collimate beam radiated by an omnidirectional antenna (monopole antenna) operating at 2.4 GHz in particular direction. The antenna design consists of a monopole antenna located at the center of a circular aluminum ground. The monopole antenna is surrounded by a cylindrical shell of conducting plasma. The plasma shield consists of 12 commercial fluorescent tubes aligned in series containing a mixture of argon gas and mercury vapor which upon electrification forms plasma columns. The plasma behaves as a conductor and acts as a reflector in radiation, in the condition where plasma frequency, cot, is higher than the operating frequency. From this concepts, when all plasma elements are activated or switched to ON, the radiation signal from the monopole antenna will trapped inside the plasma blanket and meanwhile when one or more plasma elements is deactivated (switched OFF), the radiation from the monopole antenna will escape. This antenna has the capability to change its patterns with beam direction at 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300 and 330 at frequency 2.4 GHz. The proposed antenna has been successfully fabricated and measured with conclusive results.