TRANSMISSION LINE RESONATOR, BAND-PASS FILTER AND BRANCHING FILTER

摘要

A conventional single transmission line resonator with a short circuit at both ends has the problem that the size of the resonator is constrained to 1/2 of the wavelength thereof. This transmission line resonator which has distributed coupled lines is provided with distributed coupled lines (12a and 12b) such that distributed-constant lines are disposed in parallel so as to be spaced apart by only a predetermined distance, a uniform line (11) for which one end of each of the distributed coupled lines (12a and 12b) is connected to both ends thereof, and a short-circuit ground portion (13) to which the other end of each of the distributed coupled lines (12a and 12b) is connected. This transmission line resonator which has distributed coupled lines is capable of lowering the resonant frequency thereof by increasing the coupling degree of the distributed coupled lines (12a and 12b), and therefore, it is possible to decrease the size of the resonator.