volume | PIER Journals

Abstract

In this paper, the modal method is applied to analyze coated circular waveguide terminated by a perfect electric conductor (PEC) plate. The key to this method is the accurate calculation of the propagation constants of modes in coated circular waveguide. To overcome numerical difficulties, such as overflow, encountered in solving characteristic equation, the characteristic equation is modified using Hankel function of the second kind instead of Bessel function of the first kind in the coated layers. The modified characteristic equation can be accurately solved to obtain the propagation constants even for very large circular waveguide with highly lossy coatings. To verify the modified characteristic equation, the attenuation and scattering property of circular waveguide structure have been simulated. Simulation results agree well with the reference results.

1. Lee, C. S. and S. W. Lee, "RCS of a coated circular waveguide terminated by a perfect conductor," IEEE Trans. Antennas Propagat., Vol. 35, No. 4, 391-398, 1987.
doi:10.1109/TAP.1987.1144114 Google Scholar

2. Anastassiu, H. T., J. L. Volakis, and D. C. Ross, "The mode matching technique for electromagnetic scattering by cylindrical waveguides with canonical terminations," J. Electromagn. Waves Appl., Vol. 9, No. 11/12, 1363-1391, 1995. Google Scholar

3. Moll, J. W. and R. G. Seecamp, "Calculation of radar reflecting properties of jet engine intakes using a waveguide model," IEEE Aerospace and Electronic Systems, Vol. AES-6, No. 9, 675-683, 1970. Google Scholar

4. Altintas, A., P. H. Pathak, and M. C. Liang, "A selective modal scheme for the analysis of EM coupling into or radiation from large open-ended waveguides," IEEE Trans. Antennas Propagat., Vol. 36, No. 1, 84-96, 1988.
doi:10.1109/8.1077 Google Scholar

5. Ling, H., S. W. Lee, and R. C. Chou, "High-frequency RCS of open cavities with rectangular and circular cross sections," IEEE Trans. Antennas Propagat., Vol. 37, No. 5, 648-654, 1989.
doi:10.1109/8.24193 Google Scholar

6. Ling, H., R. C. Chou, and S. W. Lee, "Shooting and bouncing rays: calculation RCS of an arbitrarily shaped cavity," IEEE Trans. Antennas Propagat., Vol. 37, No. 2, 194-205, 1989.
doi:10.1109/8.18706 Google Scholar

7. Burkholder, R. J., "High-frequency asymptotic methods for analyzing the EM scattering by open-ended waveguide cavities," Thesis (Ph.D.), 1989. Google Scholar

8. Rodríguez, J. L.F. Obelleiro, and A. G. Pino, "Iterative solutions of MFIE for computing electromagnetic scattering of large openended cavities," IEE Proc. â€” Microw. Antennas Propag., Vol. 144, No. 2, 141-144, 1997.

9. Wang, T. M. and H. Ling, "Electromagnetic scattering from three-dimensional cavities via a connection scheme," IEEE Trans. Antennas Propagat., Vol. 39, No. 10, 1505-1513, 1991.
doi:10.1109/8.97382 Google Scholar

10. Trintinalia, L. C. and H. Ling, "Electromagnetic scattering from 3-D arbitrary coated cavities via a connection scheme using triangular patches," J. Electromagn. Waves Appl., Vol. 8, No. 11, 1411-1423, 1994. Google Scholar

11. Jin, J. M., "Electromagnetic scattering from large, deep, and arbitrarily-shaped open cavities," Electromagn., Vol. 18, 3-34, 1998. Google Scholar

12. Chou, R. C. and S. W. Lee, "Modal attenuation in multilayered coated waveguides," IEEE Trans. Microwave Theory Tech., Vol. 36, No. 7, 1167-1176, 1988.
doi:10.1109/22.3652 Google Scholar

13. Harrington, R. F., Time-Harmonic Electromagnetic Fields, McGraw-Hill, 1961.

14. Yeh, C. and G. Lindgren, "Computing the propagation characteristics of radially stratified fibers: an efficient method," Appl. Optics, Vol. 16, No. 2, 483-493, 1977. Google Scholar

15. Collin, R. E., "The optimum tapered transmission line matching section," Proc. IRE, Vol. 44, No. 4, 539-548, 1956.

16. Unger, H., "Circular waveguide taper of improved design," Bell System Tech. J., Vol. 37, No. 7, 899-912, 1958. Google Scholar

Dr. Fu-Gang Hu

Professor Chao-Fu Wang

Dr. Yuan Xu

Dr. Yeow-Beng Gan