| 摘要 |
This invention provides a splitter that allows simultaneous transmission and reception using a plurality of communication methods and makes it possible to reduce loss. In said splitter (1), a first duplexer that has a first transmission-filter unit and a first reception-filter unit connected to a first antenna terminal is connected to a second duplexer that has a second transmission-filter unit and a second reception-filter unit connected to a second antenna terminal. A second transmission band used by the second transmission-filter unit and a second reception band used by the second reception-filter unit are located in the frequency region between a first transmission band used by the first transmission-filter unit and a first reception band used by the first reception-filter unit. The second transmission-filter unit and the second reception-filter unit in the second duplexer each comprise a surface-acoustic-wave filter (21) that contains the following, layered in this order: a high-acoustic-velocity material, namely a high-acoustic-velocity film (23); a low-acoustic-velocity film (24) that exhibits a lower transverse-wave propagation velocity than the high-acoustic-velocity film (23); a piezoelectric film (25) layered on top of the low-acoustic-velocity film (24); and an IDT electrode (26) layered on top of the piezoelectric film (25). |
