| 摘要 |
PROBLEM TO BE SOLVED: To provide a coaxial band-pass filter compensating and reducing the temperature variations of a resonance frequency and electrical characteristics while maintaining a cutting property and a lightness and being can obtaining stable electrical characteristics to a temperature change. SOLUTION: The coaxial band-pass filter filters the frequency band of a passing high-frequency signal by using coaxial resonators including at least resonance rods in a predetermined length being arranged in an electrically sealed space in a grounded housing 1 and connecting one ends to the housing 1 and bringing the other ends to an open state at positions separated from the housing 1 at predetermined intervals. In the coaxial band-pass filter, a material forming the housing 1 and the material forming the resonance rods configuring each of the coaxial resonators 8, 9 and 10 have mutually different thermal expansion coefficients. In the coaxial band-pass filter, aluminum abounding in the lightness and the cutting property in spite of the large thermal expansion coefficient is used as the material for the housing 1, and an invar having the small thermal expansion coefficient in spite of the difficult cutting property is used as the material for the resonance bars. COPYRIGHT: (C)2011,JPO&INPIT |
