Variable permittivity dielectric material loaded stepped-horn antenna

43to be equaled to 1 Watt/m². Table 4.3 shows convergence of the magnitude of the inputreflection coefficent, its dependence on the total mode number used in calculations for anempty and εr = 3 dielectric loaded horn antennas. As seen from Table 4.3 and Table4.4, 10 modes for the empty horn and 20 modes for the dielectric loaded horn antenna areenough to observe convergence. Total number of modes, NT in each waveguide depend onthe physical dimensions and the permittivity of loading dielectric material. Total numberof sections, NI and number of modes, NT used in all the subsequent calculations, weredetermined based on above mentioned criteria.Table 4.3 Amplitude and Phase of Reflection and Transmission Coefficient of TE 10 Modein an Empty Horn Antenna of Length L = 2.5 A. A is a Free Space Wavelength.The entire analysis were coded in MATLAB. The validity of the code developed inthis dissertation has been verified using experimental data available in the literature. Sincethere is no study available pertaining to a dielectric loaded horn antenna, verification iscarried out in two phases. First, 20 dB standard gain horn antenna gain and VSWR arecompared with the experimental results [11] . It can be seen from Table 4.5 that the theoryand measured results agreed well.