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The electromagnetic compatibility of a plasma antenna driven by HF power supplies
Published in Amir Hussain, Mirjana Ivanovic, Electronics, Communications and Networks IV, 2015
Jiansen Zhao, Xia Liu, Qinyou Hu, Wei Liu, Hao Zhang
The plasma antenna provides an integral and important part in both communication and plasma stealth technology.So far, many theoretical and experimental works have been conducted which studyimpedance, gain, phase, polar, radiation, dissipation, and many other properties. Kang and Alexeff (Alexeff et al. 2006) have successfully demonstrated (Alexeffet al. 2006 ) have successfilly demonstrated both the operation of a plasma antenna in transmission and reception, as well as stealth features on a navy test range in San Diego. Borg has reported measurements of the efficiencies and radiation patterns of plasma column antenna elements used in communications. The radiation efficiency was reported to be in the range of 25 to 50% (Borg et al. 1999,2000), and radiation patterns were found to be similar to those of antennas made from metal. The finite difference time-domain (FDTD) method (Qian et al. 2005,Li et al. 2009,2010) was used to analyze the near and far fields of a plasma antenna and to determine the feasibility of constructing diverse antenna configurations at will. Kumar and Bora (Kumar et al. 2010,2011 ) established a reconfigurable plasma antenna, and investigated the antenna properties of different plasma structures of a plasma column. By changing operating parameters such as the working pressure, drive frequency, input power, radius of the glass tube, length of the plasma column, and argon gas pressure, it was possible to transform a single plasma antenna into multiple small antenna elements. In addition, the effect on directivity with the number of plasma elements was also studied. Russo used a surfaguide device as plasma source for a plasma antenna. The surfaguide was optimized, realized, and used for the ignition of a plasma column which acted as a radiating structure. The coupling with the radiated signal network and plasma antenna efficiency were measured, demonstrating
Theoretical modeling of resonant wavelength in 3-layered plasma antennas
Published in Waves in Random and Complex Media, 2021
Mahmoud Talafi Noghani, Ali Karami Horestani, Fatemeh Sadeghikia, Mohammad Reza Dorbin
Plasma antennas are widely investigated in recent years due to their advantages over conventional metal antennas. Studies on the stealth ability of plasma antennas was carried out by Kang et al. [1,2]. Borg et al. showed experimentally that the plasma offers a promising alternative to the metal for a wide variety of radiofrequency antenna applications with reasonable efficiency and noise [3,4]. Rayner et al. reported a detailed experimental and theoretical study on the physical characteristics of surface wave driven plasma antennas in HF and VHF radio frequencies [5]. Ye et al., presented a mathematical model for the electromagnetic wave propagation in plasma antennas from which the radiation pattern could be extracted [6]. Re-configurable plasma antennas were also proposed, designed and measured by Kumar [7] and Anderson [8]. Furthermore, many researchers have studied the resonant behavior of plasma antennas. Comparison of the metal antenna with the plasma antenna has been presented in [9,10]. Theoretical, Numerical and experimental study of the surface wave driven single element and arrayed monopole antennas has been reported in [11–15] and circuit modeling and radiation properties of dipole plasma antennas has been reported in [16–18].
Electromagnetic wave transmission in hybrid fractal plasma photonic crystals through developing new kinds of productive quasi-periodic multilayers
Published in Philosophical Magazine, 2022
D. Haji Taghi Tehrani, M. Solaimani
In a pioneering study, Hojo [61] created plasma photonic crystals utilising alternative plasma and dielectric layers. Employing the dispersive and multi-mode characteristics of plasma media, the conventional photonic crystals have become tuneable structures [62]. So far, different photonic crystals utilising the plasma layers are considered, including plasma–superconductor [63], full plasma [62], plasma-metamaterials [64], plasma -mu-negative materials [65], plasma dielectric [66], etc. The plasma photonic crystals are nowadays used in various devices such as plasma lens [36], plasma antenna [35], plasma stealth aircraft [37], etc.
About the helix plasma antenna: effective factors on characteristics of radiation
Published in Waves in Random and Complex Media, 2021
Mansooreh Safi, Bahram Jazi, Samaneh Safari
The paper presents an analytical investigation of dispersion characteristic and radiation power in a plasma column with dielectric cover and helical winding as helical plasma antenna in two unmagnetized collisional and magnetized plasma cases. It was found that the helix orientation does not significantly change the number of branches while the plasma region diameter and dielectric constant affects the number of dispersion branches. The investigation of the relative radiation power revealed that the helix pinch angle, dimension of plasma core and dielectric constant confine the radiation power so that the maximum power occurred in the lower propagation constant range and corresponded to small core (collisional plasma) radius and helix angle. In addition, the use of Alumina as dielectric material leads to the increase of radiation power. Furthermore, the role of static magnetic field on the increasing number of dispersion branches was analyzed. It was shown that applying a finite magnetic field, the dispersion relation provides suitable conditions for the generation and amplification of THz waves, and applying the finite magnetic field along the axis leads to variation in the relative power. It was observed that the power behavior in magnetized plasma case is completely opposite to the behavior observed in collisional unmagnetized plasma case. From the foregoing discussion, it can be concluded that, a control over the radiation power, and hence the dispersion characteristics of guide, becomes very much obvious by the introduction of conducting helical windings and plasma medium as an active material. Results discussed in the present paper are related to the slow-wave helical plasma antennas that are expected to find many optical applications e.g. integrated optics and/or sensing, modulation of plasma antennas and optical communications.