Hanisah Mohd Zali

A Reconfigurable Monopole Antenna With Fluorescent Tubes Using Plasma Windowing Concepts for 4.9-GHz Application

This paper aimed at investigating the performance of plasma windowing concept in terms of radiation pattern, gain, and S-parameter. The antenna structure consists of 12 tubes of commercial fluorescent lamps that contain a mixture of mercury vapor and argon gas, which upon electrification, forms plasma. After getting sufficient voltage, the gas inside the fluorescent tube will ionize to plasma and form a plasma column. When all of the tubes surrounding the antenna are electrified, the radiation is trapped inside. By leaving one or more of the tubes in a nonelectrified state, apertures are formed in the plasma shield, which allow radiation to escape. The plasma frequency in this experiment is equal to 5.634e11 Hz. This antenna design is at 4.9 GHz. The designing of plasma antenna using fluorescent tubes has created advancement in antenna industry especially in reconfigurable antenna field.

A study on plasma antenna characteristics with different gases

This paper investigates the return loss characteristics of plasma antenna with 3 different gases. For this experiment, 3 plasma antennas were fabricated using glass tubes to contain 3 different gases which are neon, argon and xenon with pressure of 1 Torr. RF heating method was used to ionize the gases into plasma state. The return loss characteristic of each of the fabricated plasma antenna is measured using a vector network analyzer, to demonstrate the capability and potential of the antenna. It was found that the all gas yields return loss below -10 dB in the range of 3.5 GHz to 5.5 GHz. Return loss of the plasma tube with plasma is better than without plasma in all cases. Neon gas yielded a 200 MHz shift in the optimum frequency when measured with plasma.

Study of monopole plasma antenna using fluorescent tube in wireless transmission experiments

This paper presents a basic study on plasma monopole antenna using a single fluorescent tube and reviews the antenna performance as a transmitter and receiver. In this study, a commercially available fluorescent tube, with 0.31 m length and 0.13 m of diameter is used as the plasma antenna. When the gas inside the tube is sufficiently ionized into plasma state, it becomes conductive and allows radio frequency signals to be transmitted or received. Measurements indicated that the constructed plasma antenna yielded return loss over 10 dB from 805 MHz to 885 MHz frequency band. The antennas capability to operate as either a transmitter or receiver in the particular frequency band was verified through a series of wireless transmission experiments.

Design of a cylindrical parabolic reflector on monopole plasma antenna

A monopole plasma antenna with cylindrical parabolic reflector is proposed. A cylindrical parabolic reflector is placed at the back side of focusing signal to reflect the signal received from transmitter back to the front for increased antenna directivity. The purpose of this design is to enhance the antenna gain and produce strong antenna signal. A monopole plasma antenna positioned at the center of reflector having dimension 310 mm length and 12 mm of diameter is serve as antenna reference. The difference on antenna gain of antenna reference and plasma antenna with reflector was studied throughout the simulations and the performance in terms of return loss and radiation pattern is observed in simulation and measurement results. This antenna is operating at 4.3GHz frequency which is suitable for wireless communication applications.

A monopole fluorescent tube antenna with Wi-Fi Router

A monopole plasma antenna for Wi-Fi application at 2.4 GHz was constructed using a commercially available fluorescent tube. The plasma antenna uses a fluorescent tube with length and diameter of 0.61 m and 0.025 m, respectively. The tube contains a mixture of argon and mercury vapor, which becomes conductive when sufficiently ionized into plasma state, allowing transmissions of radio frequency signal. The constructed plasma antenna was equipped with an access-point WiFi Router which is installed inside the casing of the fluorescent tube. The antennas capability to operate as either a transmitter or receiver in the particular frequency band was verified through a series of wireless transmission experiments. Experimental measurement using a portable spectrum analysis application validated the operability of the constructed antenna.

A reconfigurable monopole antenna with fluorescent tubes by using plasma windowing concepts at 4.9GHz

This research aimed at investigating the performance of plasma windowing concept in terms of radiation pattern, gain and return loss. The antenna structure consists of 12 tubes of commercial fluorescent lamps that containing the mixture of mercury vapour and argon gas which upon electrification, forms plasma. After get sufficient voltage the gas inside the fluorescent tube will ionize to plasma and formed plasma column. When all of the tubes surrounding the antenna are electrified, the radiation is trapped inside. By leaving one or more of the tubes in a non-electrified state, apertures are formed in the plasma shield which allows radiation to escape. The plasma frequency in this experiment is equal to 5.634e11 Hz. This antenna design at 4.9 GHz. The advantages from this research, the design and construction of plasma antenna with fluorescent tubes can be beneficial in term of advancement in antennas technology especially in reconfigurable antenna.

Buffer layer configuration for wideband microstrip patch antenna for underwater applications

Underwater wireless systems require highly efficient underwater antennas to realize high data rate communication. Since most underwater environments are lossy mediums affecting the characteristics of conventional antennas, an antenna contained by a buffer-layer is considered. This paper presents a numerical study on the relationship between the buffer layer characteristics and the antenna performance when operating underwater, by means of 3D-electormagnetic simulation. A wideband microstrip circular patch antenna operating around 500 MHz frequency was used as the base antenna, where it was contained in a buffer layer filled with water with different material parameters. This study proposes the utilization of a buffer layer with dielectric constant value calculated using geometric average among air and the transmission medium. Initial simulation results indicated that the proposed formula produced the best antenna gain and commendable return loss at 500 MHz frequency band.

Development of fluorescent tube antenna array for Wi-Fi application

The design of plasma antenna array for Wi-Fi application, operating at 2.4 GHz is presented in this paper. Two pieces of fluorescent tube with same dimension of 586 mm length and 24.2 mm diameter was used for this plasma antenna. The antennas are arranged in two parallel side-by-side. The gap between two fluorescent tubes is 10 mm. Both tubes are filled with argon and mercury vapor. The proposed antenna is simulated using CST Microwave Studio to study its performance in terms of return loss, radiation pattern and gain.

RF Radiation Behavior of Rare Gas in Plasma State

This paper analyzed the performance of monopole plasma antenna based on RF charging using different number of turns of coupling sleeve and different gases. The plasma antennas were designed with 3 different gases which are argon, nitrogen and fluorescent with pressure 10 Torr. For argon plasma antenna, different pressure was designed to analyze the performance of plasma antenna with pressure 0.5 Torr, 1 Torr, 5 Torr and 10 Torr. The dimension of discharge tube for argon and nitrogen is 130 mm length and 10 mm diameter, while for fluorescent 145 mm length and 12 mm diameter. The dimension of commercialize fluorescent were used as benchmark for other plasma antenna. The commercially fluorescent tubes contain mixture of vapour mercury and argon. The plasma antennas were driven by radio frequency (RF) to sufficiently ionize the gas inside the tube to convert them into plasma state. Each antenna with different configuration of type of gas and pressure was tested while varying the number of coils turns. The antenna’s capability to operate as transceiver was verified through simulation by using CST Microwave Studio.

Effects of coupling sleeve designs on an RF charged plasma monopole antenna

This paper presents an analysis of monopole plasma antenna performance using different number of turns of coil (as coupling sleeve). The plasma antennas were fabricated with 3 different gases which are neon, argon and xenon with pressure 0.5 Torr, 5 Torr and 15 Torr. The dimension of each tube is 130 mm length and 10 mm diameter. The plasma antennas were driven by radio frequency (RF) to sufficiently ionize the gas inside the tube to convert them into plasma state. Each antenna with different configuration of type of gas and pressure was tested while varying the number of coils turns. The antennas capability to operate as transceiver was verified through measurement of receiving signal power using a spectrum analyzer. It was found that 4 turns of the coil was optimum in each configuration.