| 摘要 |
PURPOSE:To reduce coupling between two radio waves while keeping the mount area small even when the two radio waves are circularly polarized waves differing in rotating directions each other in the thin antenna handling the two radio waves differing in the frequencies each other. CONSTITUTION:A cylindrical void 3 or a coaxial void equipped with a circular slit 2 in one bottom is surrounded by a coaxial void 5, and a circular slit 4 is provided in the bottom on the side of the slit 2 of the coaxial void 5. Coaxial lines 6 and 7 are provided in the cylindrical void 3 or the coaxial void and coaxial lines 8 and 9 are provided in the coaxial void 5 so that the circularly polarized waves in one rotating direction of an upper space can be coupled in the slit 2 and the circularly polarized waves in the other rotating direction can be coupled in the slit 4. When serial resonance block bars 12 and 13 to be serially resonated at the frequency to regularly excite the slits 4 and 2 are provided in the slits 2 and 4, coupling between the both circularly polarized waves can further be reduced. |
