Patent ID: 9641155
Date: 2017-05-02
CPC Classifications: H03H

Claim:
1. A duplexer comprising: a reception filter that is connected between a reception terminal and an antenna terminal and includes one or a plurality of series resonators that are acoustic wave resonators; and a transmission filter that is connected between a transmission terminal and the antenna terminal and includes one or a plurality of acoustic wave resonators, a resonance frequency of a first series resonator that is one of the one or the plurality of series resonators and is closest to the antenna terminal in the reception filter being higher than an upper limit frequency of a reception band of the reception filter, wherein the first series resonator closest to the antenna terminal in the reception filter is divided into at least two resonators connected in series with each other, and an average resonance frequency of the at least two resonators is higher than 103% of the upper limit frequency of the reception band.