摘要 |
The present invention relates to a modified coaxial cavity resonator and a filter utilising such resonators. The cavity resonator is provided with a cavity wall (203, 204, 205), which includes on its inside at least one conductive body (201, 301, 401), which body forms an open-circuit at one end and is longitudinally, substantially shorter than a normal quarter-wave resonator. The conductive body (201, 301, 401) includes a main conductive rod (206, 405), which is in one end (209, 407) attached to the cavity wall, and at least one additional conductive protruding means (207, 302, 402, 403), such as a rod, substantially perpendicularly attached to the free end (208, 406) of the main rod (206, 405). The cross-sectional diameter of the additional rod is 0,5 to 2 times the cross-sectional diameter of the main rod (206, 405), and preferably approximately the same as the cross-sectional diameter of the main rod. By attaching the additional rod (207, 302, 402, 403) the total physical length of the conductive body is not substantially shortened, but rather redirected in another direction. |