| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact branching filter employing a surface acoustic wave filter with enhanced breakdown voltage. SOLUTION: In the SAW branching filter consisting of a transmission filter and a reception filter both with different pass bands, a transmitter side matching circuit, a receiver side matching circuit and a frequency characteristic improving element, the transmission filter consists of a surface acoustic wave resonator, the reception filter consists of a longitudinal coupling dual mode filter 105, and a 1st surface acoustic wave resonator 103 is connected in parallel with the band-pass filters and a 2nd surface acoustic wave resonator 104 is connected in parallel with the band-pass filters.
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