Patent ID: 10096882

Abstract:
A duplexer according to the present invention includes a transmission-side terminal, a reception-side terminal, a common terminal, a transmission-side circuit unit, and a reception-side circuit unit. Here, the transmission-side circuit unit is connected between the transmission-side terminal and the common terminal. The reception-side circuit unit is connected between the common terminal and the reception-side terminal. The transmission-side circuit unit includes a first transmission-side filter, a second transmission-side filter, and a transmission-side directional propagation circuit. Here, the first transmission-side filter is provided in the subsequent stage of the transmission-side terminal. The second transmission-side filter is provided in a stage subsequent to the first transmission-side filter. The transmission-side directional propagation circuit is connected between the first transmission-side filter and the second transmission-side filter. The reception-side circuit unit includes a first reception-side filter, a second reception-side filter, and a reception-side directional propagation circuit. Here, the first reception-side filter is provided in the subsequent stage of the common terminal. The second reception-side filter is provided in a stage subsequent to the first reception-side filter. The reception-side directional propagation circuit is connected between the first reception-side filter and the second reception-side filter.