2.3.1 Circular waveguide loaded with dielectric and metal discs

This model (model-6) is formed by alternatively stacking the metal and dielectric discs each of same disc hole radii rD. This is similar to conventional disc-loaded circular waveguide in which the volume between two consecutive metal discs is filled with dielectric of relative permittivity εr. Similar to conventional disc-loaded circular waveguide for the sake of analysis, one may divide the structure into two regions: central disc free region I: 0≤ r , rD, 0 , z , ∞, and disc occupied region II: rD ≤r , rW, 0 , z , L � T (Figure 7). The relevant (axial magnetic and azimuthal electric) field intensity components in the regions I and II may be given by (1), (2), (5) and (6). In (5) and (6), the radial propagation constant in region II is interpreted as γII <sup>m</sup> <sup>¼</sup> <sup>ε</sup>rk<sup>2</sup> � <sup>β</sup><sup>2</sup> m <sup>1</sup>=<sup>2</sup> [19].
