Microwave Plasma Tomography of Higher Resolution (project 1.2) Research group: Prof. Yu.A.Kravtsov, Institute of Physics, Maritime University of Szczecin Prof.. M.V.Tinin and his colleagues from the Irkutsk State University Msc. P. Berczynski, Institute

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Microwave Plasma Tomographyof Higher Resolution
(project 1.2)Research groupProf.
Yu.A.Kravtsov, Institute of Physics, Maritime
University of Szczecin Prof.. M.V.Tinin and his
colleagues from the Irkutsk State UniversityMsc.
P. Berczynski, Institute of Physics, Szczecin
University of Technology Potential partners
Dr.H.Bindslev, DenmarkProf. H.Harfuss, Germany
Dr. H. Weisen (CRPP, Lozanna).
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Microwave Phase Tomography
Phase shift due to inhomogeneities in plasma
r
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• Conventional tomography

TRANSMITTERS
H
RESOLUTION gt150 mm
H5 m 5 mm
RECEIVERS
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Features of the conventional phase tomography

• RESOLUTION gt150 mm, when CAMERA HEIGHT is H5m
  and wavelength is 5 mm.
• 2. High sensitivity to the amplitude
  fluctuations, which are inevitable due to plasma
  inhomogeneities.

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Plasma Tomography of higher resolution
(Tinin,Kravtsov, Radio Sci., 2000)
(wavelength)
Quadratic phase correction warants focusing and
highly improves resolution upto a wavelength
(5 mm instead of gt150 mm under conventional
tomography)
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Determining electron density Ne on the basis of
Tinin method
Doubly weighted Fourier transform
Quadratic term, responsible for focusing
Linear term responsible for Fourier transform
gt Ne (r)
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Features of diffraction tomography byTinin

• Strong amplitude fluctuation are now admissible
• 2. Higher resolution
• d?H/D ? ? when D ? H.
• At H5 m, ?5 mm d? ?5 mm,
• Such resolution is sufficient for revealing
  peremeters of small-scale turbulence

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Problems to solve

• 1. To choose the optimal frequency (not too high,
  not too low).
• 2 Non-plane geometry of the camera and regular
  ihomogeneity of the electron density profile
  tomographic algorithm, accounting both this
  factors is to be developed.

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• 3. One can foresee comparatively low rate of
  the traditional successive tomographic
  procedure when dealing with a matrix of 100x100
  or 50x50 transmitters and receivers, supplied
  with phasemeters, it is necessary to do 10,000 or
  2,500 phase measurements, so that parameters of
  the small-scale plasma turbulence may change. One
  of the methods to process with higher rate is to
  apply the parallel tomographic procedure, using
  different frequency for every pair of transmitter
  and receiver.

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• References
• 1. Kravtsov Yu.A., Tinin M.V. Representation of
  the wave field in randomly inhomogeneous medium
  in the form of double weighted Fourier transform
  (DWFT). Radio Sci., 2000, 35(6), 1315-1322.
• 2. Tinin M.V., Kolesnik S.N., Kravtsov Y.A.
  Integral representation for the field of the wave
  propagating in a medium with random
  inhomogeneities of different scales. Proc. SPIE,
  2002, v. 4678, pp. 605-609.
• 3. Kravtsov Yu.A. and Tinin M.V.. Ray based
  diffraction tomography of the Ionosphere and
  laboratory inhomogeneous plasma. Cosmic
  Researches 2003, 41(4), 357-358.
• 4. Tinin M.V., Kim B.C., Kolesnik S.N. and
  Kravtsov Yu.A. Inhomogeneous structure of the
  Ionosphere plasma and accuracy of the satellite
  navigation system. Proceedings of the 2004
  International Symposium on Antenna and
  Propagation (ISAP04), August 17-21 2004,
  Sendai, JAPAN, paper POS-B-10, pp. 1105-1108.