| 摘要 |
PURPOSE:To attain miniaturization and light weight of the titled circuit by using a waveguide having a low cut-off frequency and provided with many posts and using a connecting waveguide provided with many posts whose height is changed gradually. CONSTITUTION:The titled circuit consists of a square waveguide 1 formed by providing many posts 8 to a waveguide whose cut-off frequency is lower than fL, a square waveguide 2 whose cut-off frequency is lower than fH and higher than the fL, a square connecting waveguide 3 provided with many posts 8 so that the height is changed gradually, a main waveguide 4, a sub-waveguide 6 coupled with the main waveguide 4 via a coupling hole 5 and a series resonance element 7. The radio wave in the fH is propagated in the connecting waveguide 3 without being interrupted in the branching after circuit and the radio wave in the fL is cut off on the way and reflected completely, then the circuit acts similarly like a conventional branching filter circuit. |
