N. P. Balabukha - Ph.D. (Eng.), Associate Professor, Head of Laboratory, Institute of Theoretical and Applied Electrodynamics of RAS. E-mail: n_bala@mail.ru N. L. Men-shikh - Post-graduate Student, Moscow Institute of Physics and Technology, Engineer, Institute of Theoretical and Applied Electrodynamics of RAS. E-mail: sula1989@mail.ru V. S. Solosin - Ph.D. (Phys.-Math.), Leading Research Scientist, Institute of Theoretical and Applied Electrodynamics of RAS. E-mail: svs15105@yandex.ru

This paper presents theoretical and experimental studies of the field distribution in the quiet zone of the tapered anechoic chamber (AEC) operating in the frequency range from 100 MHz to 1 GHz. The computer model of a tapered AEC has been created. In this model radio-absorbing material is replaced by a dielectric layer with a given reflectance. Electrodynamic calculation has been carried out by the method of moments (integral equations method) using FEKO. Exploitation of ITAE RAS cluster allows carrying out simulation of the chamber field distribution at low frequencies. A tapered part of the chamber is 15 m in length. This part of the chamber is covered with wedge RAM. A source of radiation is placed in the mouth of the chamber (the calculation is provided for two types of sources: the dipole and vibrator antenna). The object is placed in the part rectangular of the chamber with the 8,3 × 8,3 m cross section and 10 m in length. This part of AEC is covered with pyramidal RAM. The quiet zone of the tapered AEC is a horizontal cylinder 3 m in diameter and 4 m in length. To verify the calculation results, the distribution of the electromagnetic field was measured in the quiet zone of a scale model of the chamber. Measurement results are in a good agreement with results of the numerical calculation for frequencies 100 - 800 MHz. The results of electrodynamic analysis have showed that for the tapered AEC the non-uniformity of the field in the quit zone 3 m in diameter does not exceed ± 1 dB, and the phase of the non-uniformity is no more than ± 12,5° up to 400 MHz. At higher frequencies the phase should be corrected by a lens. The cross-polarization component of the field is 25-35 dB less than the main component in the chamber quiet zone.

 

1. Emerson W.H., Sefton H.B. An improved design for indoor ranges // Proceedings of the IEEE. 1965. V. 53. № 8. P. 1079-1081.
2. King H., Shimabukuro T., Wong J. Characteristics of a tapered anechoic chamber // IEEE Trans. on Antennas and Propagat. 1967. V. 15. № 3. P. 488-490.
3. Balabukha N.P., Zubov A.S., Solosin V.S. Kompaktnye poligony dlja izmerenija kharakteristik rassejanija. M.: Nauka. 2007.
4. Lee K.H., Chen C.C., Teixeira F.L., Lee R. Numerical study of a UWB dual-polarized feed design for enhanced tapered chambers // Antennas and Propagation Society International Symposium IEEE. 2003. V. 1. P. 265-268.
5. Lee K.H., Chen C.C., Lee R. Design of a tapered chamber feed using the FDTD method // Proceedings of ISAP. 2004. Sendai, Japan. P. 1013-1016.
6. Lee K.H., Chen C.C., Lee R. Novel dual-polarized tapered-chamber feed design concepts // Antennas and Propagation Magazine. IEEE. 2005. V.47. № 4. P. 214-218.
7. Lee K.H., Chen C.C., Lee R., Burnside W.D. Numerical analysis of a novel tapered chamber feed antenna design // AMTA. November. 2002.
8. Moharam M.G., Pommet D.A., Grann E.B., Gaylord T.K. Stable implementation of the rigorous coupled-wave analysis for surface-relief gratings: enhanced transmittance matrix approach // Journal of the Optical Society of America A. 1995. V. 12. № 5. P. 1077-1086.
9. Nikitenko A.V., Zubov A.S., SHapkina N.E. Modelirovanie ehlektromagnitnogo rassejanija na radiopogloshhajushhem materiale metodom svjazannykh voln // Matematicheskoe modelirovanie. 2014. T. 26. № 9. S. 18-32.
10. Hemming L.H.Electromagnetic anechoic chambers. A fundamental design and specification guide. New York: IEEE Press and Wiley Interscience. 2002.
11. Sajjt kompanii «ETSLindgren». URL: http://www.ets-lindgren.com/3164-01 (data obrashhenija 20.09.2014).