| 摘要 |
A duplexer includes: a transmission filter connected between a common terminal and a transmission terminal; and a reception filter connected between the common terminal and a reception terminal, wherein the reception filter includes resonators located on a piezoelectric substrate, at least one resonator of the resonators is grounded, and a resonator located at a side closest to the common terminal out of the grounded resonator is a divided resonator that is divided into two or more, and a resonance frequency fr of the divided resonator is in a range of fr=2×(fTL to fTH)-(fRL to fRH) when a pass frequency of the transmission filter is fTL to fTH and a pass frequency of the reception filter is fRL to fRH. |
