Communication module
A second-signal first transmission line operates as an open stub in a state in which a second antenna terminal is open. Therefore, a first signal is attenuated that is transmitted from a branch point between a second-signal first transmission line and a second-signal second transmission line to a second communication unit through a second common transmission line. In a case in which a two-antenna communication module performs communication of the first signal and communication of a second signal at the same time by connecting a shared antenna to a first antenna terminal.
1. A communication module that concurrently performs wireless communication of a first signal and wireless communication of a second signal, the first signal and second signal being in different frequency bands, the communication module comprising:
a wiring board that includes a first antenna terminal connectable to a first-signal antenna used in communication of the first signal or to a shared antenna used in both communication of the first signal and communication of the second signal, and a second antenna terminal connectable to a second-signal antenna used in communication of the second signal;
a first communication unit disposed on the wiring board, the first communication unit transmitting the first signal; and
a second communication unit disposed on the wiring board, the second communication unit receiving the second signal;
wherein
the wiring board includes:
a first-signal transmission line disposed in a path that interconnects the first antenna terminal and the first communication unit, the first signal being transmitted through the first signal transmission line,
a second-signal first transmission line disposed in a path that interconnects the second antenna terminal and the second communication unit, the second signal being capable of being transmitted through the second-signal first transmission line in a state in which the second-signal antenna is connected to the second antenna terminal,
a second-signal second transmission line disposed in a path that interconnects the first antenna terminal and the second communication unit, the second signal being transmitted through the second-signal second transmission line,
a first common transmission line provided so as to be shared between a path that interconnects the first antenna terminal and the first-signal transmission line and a path that interconnects the first antenna terminal and the second-signal second transmission line, and
a second common transmission line provided so as to be shared between a path that interconnects the second-signal first transmission line and the second communication unit and a path that interconnects the second-signal second transmission line and the second communication unit, and
the second-signal first transmission line functions as an open stub that attenuates the first signal transmitted from a branch point between the second-signal first transmission line and the second-signal second transmission line to the second communication unit through the second common transmission line in a state in which the second antenna terminal is open.
2. The communication module according to claim 1 , wherein the second-signal first transmission line has a length equal to an odd-number multiple of one-fourth a wavelength of the first signal.
3. The communication module according to claim 2 , wherein a conductive pattern of the second-signal first transmission line is formed on a part mounting surface of the wiring board, the first communication unit and second communication unit being mounted on the part mounting surface.
4. The communication module according to claim 3 , wherein the second antenna terminal includes an electrode provided at an end of the wiring board.
5. The communication module according to claim 1 , further comprising a duplexer disposed on a signal path between the first-signal transmission line and the first common transmission line and a signal path between the second-signal second transmission line and the first common transmission line, wherein:
the shared antenna is connected to the first antenna terminal, and
the second antenna terminal is made to be open.
6. The communication module according to claim 1 , further comprising a band pass filter disposed on the first-signal transmission line, the band pass filter passing the first signal.
7. A communication module that concurrently performs wireless communication of a first signal and wireless communication of a second signal, the first signal and second signal being in different frequency bands, the communication module comprising:
a wiring board that includes a first antenna terminal connectable to a first-signal antenna used in communication of the first signal or to a shared antenna used in both communication of the first signal and communication of the second signal, and also includes a second antenna terminal connectable to a second-signal antenna used in communication of the second signal;
a first communication unit disposed on the wiring board, the first communication unit transmitting the first signal; and
a second communication unit disposed on the wiring board, the second communication unit receiving the second signal;
wherein
the wiring board includes:
a first-signal transmission line disposed in a path that interconnects the first antenna terminal and the first communication unit, the first signal being transmitted through the first signal transmission line,
a second-signal first transmission line disposed in a path that interconnects the second antenna terminal and the second communication unit, the second signal being transmitted through the second-signal first transmission line,
a second-signal second transmission line disposed in a path that interconnects the first antenna terminal and the second communication unit, the second signal being capable of being transmitted through the second-signal second transmission line in a state in which the shared antenna is connected to the first antenna terminal,
a first common transmission line provided so as to be shared between a path that interconnects the first antenna terminal and the first-signal transmission line and a path that interconnects the first antenna terminal and the second-signal second transmission line, and
a second common transmission line provided so as to be shared between a path that interconnects the second-signal first transmission line and the second communication unit and a path that interconnects the second-signal second transmission line and the second communication unit, and
the second-signal second transmission line functions as an open stub that attenuates the first signal transmitted from a branch point between the second-signal first transmission line and the second-signal second transmission line to the second communication unit through the second common transmission line in a state in which the second-signal second transmission line is separated from the first common transmission line and first-signal transmission line.
8. The communication module according to claim 7 , wherein the second-signal second transmission line has a length equal to an odd-number multiple of one-fourth a wavelength of the first signal in a state in which the second-signal second transmission line is separated from the first common transmission line and first-signal transmission line.