Title: 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
1Microwave 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).
2Microwave Phase Tomography
Phase shift due to inhomogeneities in plasma
r
3TRANSMITTERS
H
RESOLUTION gt150 mm
H5 m 5 mm
RECEIVERS
4Features 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.
5Plasma 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)
6Determining 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)
7Features 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 -
-
8Problems 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.
9- 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.
10- 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.