| 摘要 |
PURPOSE:To arrange two kinds of cavity resonators with different resonant frequency at an angular position of 180 deg. along the circumference of the tube axis of a circular waveguide and to fit them to the dielectric-plate-equipped circular waveguide to form a single unit. CONSTITUTION:Cavity resonator 9 is combined through a coupling hole 8 with linear polarization (a) whose direction of the electric field is in parallel with dielectric 4, and resonates with frequency f4. Cavity resonator 6 is placed in a staggered position with cavity resonator 9, and their interval in the tube-axis direction is selected at 1/4 of the intratube wave-length of circular waveguide 1 in f2 and f1 respectively. The phase difference between polarized waves due to metallic plate 3 and dielectric plate 4 and the effects of resonator 6 are the same as those for the conventional type. On the other hand, resonator 9 couples only with polarization (a) and resonates; and in the vicinity of f1 which is higher than f3, it advances the phase of polarization (a) as conductance in parallel with the line. Whereas, the effect suddenly decreases above f1. With this constitution, flat phase characteristics over a wide band can be implemented by a waveguide which has the same short axes of cavity resonators 6 and 9 and dielectric plate 4. |
