| Millimeter planar antenna and mode converter are presented. Antennas with high radiation performance are the key part of high-power radiation system. At millimeter-wave band, Fresnel Zone Plate (FZP) antenna has the advantages of simple structure, planar configuration and low cost, while giving performance comparable to the parabolic antenna. In addition, a mode converter is required when testing the millimeter-wavelength radiation system, which converting the output of the testing system into that of the gyrotron. Therefore 8mm planar antenna and mode converter are presented.Fresnel zone phase correcting plate antenna is a new type of planar antenna which is used in high-power millimeter-wavelength radiation system. A numerical program solving the radiation field of FZP antenna has been programmed according to the vector diffraction theory. In order to validate the program, an experiment antenna has been designed. The numerical results are consistent with stimulated and measured ones. The results show its good focusing and radiating characteristic, and it has similar aperture efficiency to a parabolic antenna, given the same aperture size.A novel mode converter is presented, taking advantage of quasi-optical characteristic of millimeter wave. This mode converter efficiently converts the TE10 rectangular waveguide mode to the TE01 circular waveguide mode. The sidewall coupling structure is used to generate TE01 mode. The operating principle has been discussed by using the"partial wave"theory. The mode converter has been simulated and optimized. According to the optimized structure, the converter is fabricated and the radiation field is tested. The measured results are consistent with simulated ones. |
PDF Full Text Request