Recoverying Form of the Scattering Source Whose Field Is Distorted by the Noise

2017;
: pp. 17 - 24
1
Karpenko Physico-Mechanical Institute of the NAS of Ukraine
2
Karpenko Physico-Mechanical Institute of the National Academy of Sciences of Ukraine, Lviv, Ukraine

Scattering signals is one of the basic natural processes, which is a consequence of energy losses and manifests in the form of variety of radiation what propagating in space. The cause of the scattering signal is the interaction with the environment. The result of this interaction is not only scattering but also weakening the signal.

On the one hand scattering is considered as a negative effect, but on the other — as a possible way for finding form of the scatterer of the signal.

Measuring the scattered field has a great practical importance, because the power of scattered field is usually much less than the power of field of the original signal. Moreover in the real condition always is present noise including the noise of the measuring devices.

In the paper we explored the problem of recovering form of the scattering source in the uniform environment. The input data of this problem is the information about a set of receivers and the measured scattering field distorted by the noise. We showed solving of this problem needs to recover the function of two variables for its radon image. The scientific novelty lies in the fact that unlike the known methods of restoring the form of the source of scattering, a new approach is proposed in the work, in which it is not necessary to know the information about the distant field, as well as the coordinate and the angle at which the source of the signal relative to the receiver system is located.

For the proposed method established the dependence of the precision noise from the angle of rotation system receivers.

1. Philip M. Morse. Vibration and Sound / Philip M. Morse. — London: McGraw-Hill Book Company, Inc., 1948. — S. 294–380. 2. Angell T.S. On a numerical method for inverse acoustic scattering / Angell T. S., Jiang X. and Kleinman R. E. // Inverse Problems. — 1997. — Vol. 13. — S. 531–545. 3. Colton D. A simple method for solving inverse scattering problems in the resonance region / Colton D. and Kirsch A. // Inverse Problems. — 1996. — Vol. 12. — S. 383–393. 4. Colton D. The Linear Sampling Method for Solving the Electromagnetic/ Colton D., Haddar H. and Monk P. // Inverse Scattering Problem. SIAM J. Sci. Comput. — 2002. — Vol. 24(3). — S. 719–731. 5. Fioralba Cakoni Analysis of two linear sampling methods applied to electromagnetic imaging of buried objects / Fioralba Cakoni, M’Barek Fares and Houssem Haddar// Inverse Problems. — 2006. — Vol. 22(3). — S. 845–868. 6. Davis M. E. Numerical Methods and Modeling for Chemical Engineers / Davis M. E. — Wiley, New York: Chichester, Brisbane, 1984. — S. 127–146. 7. Radon J. Über die Besimmung von Functionen durch ihre Integralwerte längs gewisser Mannigfaltigkeiten / Radon J. — Berichte Sächsische Academie der Wissenschaften, Mathematisch, Physische Klasse 69, 1917, s. 262–277. 8. Jorge Bernal del Nozal Use of Projection and Back-projection Methods/ Jorge Bernal del Nozal. — Computer Vision Center Edifici O, Universitat Aut`onoma de Barcelona, 2009. — S. 23–28.