| 摘要 |
PROBLEM TO BE SOLVED: To obtain an easy-to-manufacture millimeter wave band filter which allows for sufficient wide area attenuation characteristics in a frequency band exceeding 100GHz.SOLUTION: First waveguide 21 and second waveguide 22 are arranged to pass each other in parallel while closing one ends 21a, 22a of a waveguide having a rectangular cross section and propagating electromagnetic waves of a predetermined frequency or more in the millimeter wave band, respectively, and facing the side faces (inner side face) 21b, 22b on the short side surrounding the one end side thereof each other. A manifold 23 couples the side faces on the short side of the first waveguide 21 and second waveguide 22 by a waveguide of a predetermined caliber, and regulates transmission ratio to the second waveguide 22 so as to decrease as the frequency of electromagnetic waves incident to the first waveguide 21 increases. |
