# Electromagnetic wave scattering by quasi-homogeneous obstacles

N. L. Tsitsas, C. A. Valagiannopoulos

Research output: Chapter in Book/Report/Conference proceedingConference contribution

### Abstract

In this work we investigate the electromagnetic wave scattering phenomena by quasi-homogeneous obstacles, namely obstacles with wavenumber functions not exhibiting large variations from an average value $\bar k$. First, we express the field coefficients by means of a T-matrix method for the corresponding piecewise-homogeneous scatterer and then perform the best linear approximation by differentials to express these coefficients as linear combinations of the distances of the wavenumber samples from k. Moreover, the total far-field pattern of the quasi-homogeneous scatterer is decomposed into that of the respective homogeneous scatterer with wavenumber k plus the perturbation far-field pattern, depending exclusively on the wavenumber's deviations from k. Numerical results are presented concerning (i) the far-field patterns, computed by the proposed technique and the T-matrix method, (ii) the variations of the perturbation far-field pattern, and (iii) the prediction of each layer's contribution to the far-field.

Original language English Proceedings of the 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering: Advanced Topics in Scattering and Biomedical Engineering World Scientific Publishing Co. Pte Ltd 169-176 8 9814322024, 9789814322027 Published - 2010 Yes 2009 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering - Patras, GreeceDuration: Oct 9 2009 → Oct 11 2009

### Other

Other 2009 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering Greece Patras 10/9/09 → 10/11/09

### Fingerprint

Electromagnetic wave scattering
Far-field Pattern
Wave Scattering
Electromagnetic Scattering
Electromagnetic Wave
Matrix Method
Express
Perturbation
Linear Approximation
Coefficient
Far Field
Best Approximation
Linear Combination
Deviation
Numerical Results
Prediction

### ASJC Scopus subject areas

• Biomedical Engineering
• Applied Mathematics

### Cite this

Tsitsas, N. L., & Valagiannopoulos, C. A. (2010). Electromagnetic wave scattering by quasi-homogeneous obstacles. In Proceedings of the 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering: Advanced Topics in Scattering and Biomedical Engineering (pp. 169-176). World Scientific Publishing Co. Pte Ltd.
Proceedings of the 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering: Advanced Topics in Scattering and Biomedical Engineering. World Scientific Publishing Co. Pte Ltd, 2010. p. 169-176.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Tsitsas, NL & Valagiannopoulos, CA 2010, Electromagnetic wave scattering by quasi-homogeneous obstacles. in Proceedings of the 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering: Advanced Topics in Scattering and Biomedical Engineering. World Scientific Publishing Co. Pte Ltd, pp. 169-176, 2009 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering, Patras, Greece, 10/9/09.
Tsitsas NL, Valagiannopoulos CA. Electromagnetic wave scattering by quasi-homogeneous obstacles. In Proceedings of the 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering: Advanced Topics in Scattering and Biomedical Engineering. World Scientific Publishing Co. Pte Ltd. 2010. p. 169-176
Tsitsas, N. L. ; Valagiannopoulos, C. A. / Electromagnetic wave scattering by quasi-homogeneous obstacles. Proceedings of the 9th International Workshop on Mathematical Methods in Scattering Theory and Biomedical Engineering: Advanced Topics in Scattering and Biomedical Engineering. World Scientific Publishing Co. Pte Ltd, 2010. pp. 169-176
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