Analysis of pentagonal waveguides for high-power transmission by use of eigenmode expansion

In this paper, the eigenmode expansion technique is proposed to analyze the pentagonal waveguide for high-power microwave transmission. The analysis i s implemented by expanding the electromagnetic fields inside a pentagonal w aveguide with the infinite summation of the cylindrical waveguide modes. To obtain the numerical cutoff wavelength, the infinite summation has to be t runcated, and then the point-matching technique is used on the boundary. On ce the linear equation is obtained, which is the function of the cutoff wav enumber, the determinant about the eigenvalue is solved. The numerical resu lts are in good agreement with those published. The propagation characteris tics of the pentagonal waveguides, such as attenuation constant, power-hand ling capability, and characteristic impedance, are also analyzed. (C) 2000 John Wiley & Sons, Inc.