Analysis of Radiation Patterns of Compound Box-Horn Antenna

A new type of antenna named as compound box-horn antenna is designed and analyzed for its radiation pattern.The present analysis is based on plane wave spectra for three-dimensional fields.The compound box-horn antenna is obtained by combining modified box-horn and pyramidal horn antennas, in which modified box-horn is coupled to pyramidal horn to excite TE 10 -and TE 30modes at the input of pyramidal horn.Thus, the compound boxhorn antenna has properties and advantages of both the modified box-horn and pyramidal horn antennas.The radiation patterns and corresponding half-power beam widths (HPBWs) of compound boxhorn antenna in free-space are computed at 10 GHz and compared for different flare angles in E-and H-planes of larger size pyramidal horn section of the compound box-horn.The results for HPBWs in Eand H-planes demonstrate that the radiation patterns in E-and Hplanes for compound box-horn can be made narrower by decreasing the flare angles in both E-and H-planes of larger size pyramidal horn section of the compound box-horn.The radiation patterns of compound box-horn are also compared with those for TE 10 -mode pyramidal horn of same aperture size and it found that the former horn is narrower in E-as well as H-plane than the latter.The analysis has been validated against the experimental results available in the literature.The work presented here can provide useful design