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Title: Radiation characteristics of input power from surface wave sustained plasma antenna

Abstract

This paper reports radiation characteristics of input power from a surface wave sustained plasma antenna investigated theoretically and experimentally, especially focusing on the power consumption balance between the plasma generation and the radiation. The plasma antenna is a dielectric tube filled with argon and small amount of mercury, and the structure is a basic quarter wavelength monopole antenna at 2.45 GHz. Microwave power at 2.45 GHz is supplied to the plasma antenna. The input power is partially consumed to sustain the plasma, and the remaining part is radiated as a signal. The relationship between the antenna gain and the input power is obtained by an analytical derivation and numerical simulations. As a result, the antenna gain is kept at low values, and most of the input power is consumed to increase the plasma volume until the tube is filled with the plasma whose electron density is higher than the critical electron density required for sustaining the surface wave. On the other hand, the input power is consumed to increase the electron density after the tube is fully filled with the plasma, and the antenna gain increases with increasing the electron density. The dependence of the antenna gain on the electron densitymore » is the same as that of a plasma antenna sustained by a DC glow discharge. These results are confirmed by experimental results of the antenna gain and radiation patterns. The antenna gain of the plasma is a few dB smaller than that of the identical metal antenna. The antenna gain of the plasma antenna is sufficient for the wireless communication, although it is difficult to substitute the plasma antenna for metal antennas completely. The plasma antenna is suitable for applications having high affinity with the plasma characteristics such as low interference and dynamic controllability.« less

Authors:
 [1];  [2];  [3];  [4]
  1. Advanced Technology R&D Center, Mitsubishi Electric Corporation, Amagasaki, Hyogo 661-8661 (Japan)
  2. Information Technology R&D Center, Mitsubishi Electric Corporation, Kamakura, Kanagawa 247-8501 (Japan)
  3. Communication System Center, Mitsubishi Electric Corporation, Amagasaki, Hyogo 661-8661 (Japan)
  4. Department of Electronic System Engineering, The University of Shiga Prefecture, Hikone, Shiga 522-8533 (Japan)
Publication Date:
OSTI Identifier:
22599873
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 9; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANTENNAS; ARGON; COMPUTERIZED SIMULATION; DIELECTRIC MATERIALS; ELECTRON DENSITY; ELECTRONS; GAIN; GHZ RANGE 01-100; GLOW DISCHARGES; MERCURY; MICROWAVE RADIATION; PLASMA; SIGNALS; SURFACES; TUBES; WAVE PROPAGATION; WAVELENGTHS

Citation Formats

Naito, T., E-mail: Naito.Teruki@bc.MitsubishiElectric.co.jp, Yamaura, S., Fukuma, Y., and Sakai, O.. Radiation characteristics of input power from surface wave sustained plasma antenna. United States: N. p., 2016. Web. doi:10.1063/1.4962225.
Naito, T., E-mail: Naito.Teruki@bc.MitsubishiElectric.co.jp, Yamaura, S., Fukuma, Y., & Sakai, O.. Radiation characteristics of input power from surface wave sustained plasma antenna. United States. doi:10.1063/1.4962225.
Naito, T., E-mail: Naito.Teruki@bc.MitsubishiElectric.co.jp, Yamaura, S., Fukuma, Y., and Sakai, O.. 2016. "Radiation characteristics of input power from surface wave sustained plasma antenna". United States. doi:10.1063/1.4962225.
@article{osti_22599873,
title = {Radiation characteristics of input power from surface wave sustained plasma antenna},
author = {Naito, T., E-mail: Naito.Teruki@bc.MitsubishiElectric.co.jp and Yamaura, S. and Fukuma, Y. and Sakai, O.},
abstractNote = {This paper reports radiation characteristics of input power from a surface wave sustained plasma antenna investigated theoretically and experimentally, especially focusing on the power consumption balance between the plasma generation and the radiation. The plasma antenna is a dielectric tube filled with argon and small amount of mercury, and the structure is a basic quarter wavelength monopole antenna at 2.45 GHz. Microwave power at 2.45 GHz is supplied to the plasma antenna. The input power is partially consumed to sustain the plasma, and the remaining part is radiated as a signal. The relationship between the antenna gain and the input power is obtained by an analytical derivation and numerical simulations. As a result, the antenna gain is kept at low values, and most of the input power is consumed to increase the plasma volume until the tube is filled with the plasma whose electron density is higher than the critical electron density required for sustaining the surface wave. On the other hand, the input power is consumed to increase the electron density after the tube is fully filled with the plasma, and the antenna gain increases with increasing the electron density. The dependence of the antenna gain on the electron density is the same as that of a plasma antenna sustained by a DC glow discharge. These results are confirmed by experimental results of the antenna gain and radiation patterns. The antenna gain of the plasma is a few dB smaller than that of the identical metal antenna. The antenna gain of the plasma antenna is sufficient for the wireless communication, although it is difficult to substitute the plasma antenna for metal antennas completely. The plasma antenna is suitable for applications having high affinity with the plasma characteristics such as low interference and dynamic controllability.},
doi = {10.1063/1.4962225},
journal = {Physics of Plasmas},
number = 9,
volume = 23,
place = {United States},
year = 2016,
month = 9
}
  • We present experimental results on measuring the emittance of short-pulsed (≤100 μs) high-current (80–100 mA) ion beams of heavy gases (Nitrogen, Argon) formed from a dense plasma of an ECR source of multiply charged ions (MCI) with quasi-gas-dynamic mode of plasma confinement in a magnetic trap of simple mirror configuration. The discharge was created by a high-power (90 kW) pulsed radiation of a 37.5-GHz gyrotron. The normalized emittance of generated ion beams of 100 mA current was (1.2–1.3) π mm mrad (70% of ions in the beams). Comparing these results with those obtained using a cusp magnetic trap, it was concluded thatmore » the structure of the trap magnetic field lines does not exert a decisive influence on the emittance of ion beams in the gas-dynamic ECR source of MCI.« less
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