Directional coupler
A directional coupler includes a main line through which a signal is transmitted, first and second sub-lines that are selectively coupled to the main line, and a common output port that outputs a detection signal generated by the signal transmitted through the main line, wherein a first degree of coupling between the main line and the first sub-line is different than a second degree of coupling between the main line and the second sub-line.
1. A directional coupler comprising:
a main line through which a signal is transmitted;
at least two sub-lines that are selectively coupled to the main line;
a common output port that outputs a detection signal generated by the signal transmitted through the main line;
a termination circuit; and
at least one switch circuit that:
selectively connects one of the at least two sub-lines to the common output port and the termination circuit;
selectively disconnects another one of the at least two sub-lines from the common output port and the termination circuit; and
selectively connects one end of the one of the at least two sub-lines to one of the common output port and the termination circuit and another end of the one of the at least two sub-lines to another one of the termination circuit and the common output port; wherein
a degree of coupling between the main line and one of the at least two sub-lines is different from a degree of coupling between the main line and another one of the at least two sub-lines;
the at least one switch circuit includes first and second switch circuits;
the first switch circuit selectively connects the one end of the one of the at least two sub-lines to the one of the common output port and the termination circuit and the another end of the one of the at least two sub-lines to the another one of the termination circuit and the common output port; and
the second switch circuit selectively connects the one of the at least two sub-lines to the common output port and the termination circuit and disconnects the another one of the at least one sub-lines from the common output port and the termination circuit.
2. The directional coupler according to claim 1 , wherein the at least two sub-lines have one or more of different sizes, different distances from the main line, or different lengths.
3. The directional coupler according to claim 1 , wherein the first and second switch circuits are defined by a common switch circuit.
4. The directional coupler according to claim 1 , wherein the first and second switch circuits are separate switch circuits.
5. The directional coupler according to claim 1 , further comprising a shunt switch between the first and second switch circuits and connected to ground.
6. The directional coupler according to claim 1 , wherein at least one of the first and second switch circuits is provided separately for each of the first and second sub-lines.
7. A directional coupler comprising:
a main line through which a signal is transmitted;
at least two sub-lines that are selectively coupled to the main line;
a common output port that outputs a detection signal generated by the signal transmitted through the main line;
a termination circuit; and
at least one switch circuit that:
selectively connects one of the at least two sub-lines to the common output port and the termination circuit;
selectively disconnects another one of the at least two sub-lines from the common output port and the termination circuit; and
selectively connects one end of the one of the at least two sub-lines to one of the common output port and the termination circuit and another end of the one of the at least two sub-lines to another one of the termination circuit and the common output port; wherein
a degree of coupling between the main line and one of the at least two sub-lines is different from a degree of coupling between the main line and another one of the at least two sub-lines; and
the at least one switch circuit includes:
a series switch connected between at least one of the at least two sub-lines and the common output port; and
a shunt switch connected between the at least one of the at least two sub-lines and ground.
8. The directional coupler according to claim 7 , wherein
the shunt switch is connected between the at least one of the at least two sub-lines and the common output terminal and is connected to ground; and
the shunt switch is open to define an electrostatic discharge device.
9. The directional coupler according to claim 7 , wherein the termination circuit includes at least two termination circuits that are provided separately for the at least two sub-lines.
10. The directional coupler according to claim 7 , wherein the at least two sub-lines have one or more of different sizes, different distances from the main line, or different lengths.
11. The directional coupler according to claim 7 , wherein the termination circuit is a variable termination circuit.
12. The directional coupler according to claim 7 , further comprising
a variable matching circuit between at least one of the at least two sub-lines and the common output port; and
a variable attenuator between the at least one of the at least two sub-lines and the common output port.
13. A directional coupler comprising:
a main line through which a signal is transmitted;
at least two sub-lines that are selectively coupled to the main line;
a common output port that outputs a detection signal generated by the signal transmitted through the main line;
a termination circuit; and
at least one switch circuit that:
selectively connects one of the at least two sub-lines to the common output port and the termination circuit;
selectively disconnects another one of the at least two sub-lines from the common output port and the termination circuit; and
selectively connects one end of the one of the at least two sub-lines to one of the common output port and the termination circuit and another end of the one of the at least two sub-lines to another one of the termination circuit and the common output port; and
first and second electrical length adjustment loading circuits; wherein
a degree of coupling between the main line and one of the at least two sub-lines is different from a degree of coupling between the main line and another one of the at least two sub-lines;
the at least one switch circuit includes first, second, third switch circuits; and
the third switch circuit selectively connects and disconnects the first and second electrical length adjustment loading circuits to the another one of the at least two sub-lines that is disconnected from the common output port and the termination circuit.
14. The directional coupler according to claim 13 , wherein at least one of the first and second electrical length adjustment loading circuits includes a capacitor connected in series between the third switch circuit and ground.
15. The directional coupler according to claim 13 , wherein
the first switch circuit selectively connects the one end of the one of the at least two sub-lines to the one of the common output port and the termination circuit and the another end of the one of the at least two sub-lines to the another one of the termination circuit and the common output port;
the second switch circuit selectively connects the one of the at least two sub-lines to the common output port and the termination circuit and selectively disconnects the another one of the at least one sub-lines from the common output port and the termination circuit;
at least one of the first and second electrical length adjustment loading circuits and the third switch are defined by the first switch circuit;
the first switch circuit includes a series switch provided between at least one of the at least two sub-lines and the common output port, and a shunt switch provided between the at least one of the two sub-lines and ground; and
a capacitance is provided when the series switch which is open.
16. The directional coupler according to claim 13 , wherein
the first switch circuit selectively connects the one end of the one of the at least two sub-lines to the one of the common output port and the termination circuit and the another end of the one of the at least two sub-lines to the another one of the termination circuit and the common output port;
the second switch circuit selectively connects the one of the at least two sub-lines to the common output port and the termination circuit and selectively disconnects the another one of the at least one sub-lines to the common output port and the termination circuit;
at least one of the first and second electrical length adjustment loading circuits and the third switch are defined by the second switch circuit;
the second switch circuit includes a series switch provided between at least one of the at least two sub-lines and the common output port, and a shunt switch provided between the at least one of the two sub-lines and ground; and
a capacitance is provided when the series switch which is open.
17. The directional coupler according to claim 13 , wherein the at least two sub-lines have one or more of different sizes, different distances from the main line, or different lengths.