Directional Coupler

Abstract

The present invention provides a directional coupler (10) comprising a main line (20), a secondary line (31), a secondary line (32), and a switch (SW91). The secondary lines (31) and (32) are configured to be electromagnetically coupled to the main line (20). The switch (SW91) is connected between ends (311) and (312) of the secondary line (31) to switch between short-circuiting and disconnecting the ends (311) and (312).

Description

Technical Field

[0001] This invention relates to a directional coupler having a main line and multiple secondary lines. Background Technology

[0002] Patent document 1 describes a directional coupler comprising a main line and multiple coupling lines. The multiple coupling lines have a first coupling line and a second coupling line, and are respectively configured to couple with the electromagnetic field of the main line.

[0003] Furthermore, the directional coupler described in Patent Document 1 includes a coupling output terminal, a terminating resistor, and a switching circuit. The switching circuit switches between the first coupling line and the second coupling line and is connected to the coupling output terminal and the terminating resistor.

[0004] Patent Document 1: US Patent No. 10,498,004

[0005] However, as shown in Patent Document 1, in a structure using multiple coupled lines (sub-lines), the transmission characteristics of high-frequency signals flowing through the main line are degraded due to the coupling capacitance generated between the main line and the multiple sub-lines. Summary of the Invention

[0006] Therefore, the object of the present invention is to suppress the degradation of the transmission characteristics of high-frequency signals flowing through the main line in a directional coupler having multiple secondary lines.

[0007] One embodiment of the directional coupler of the present invention includes a main line, a first secondary line, a second secondary line, and a first switching circuit. The first and second secondary lines are configured to be electromagnetically coupled to the main line. The first switching circuit is connected between a first terminal and a second terminal of the first secondary line, switching between short-circuiting and opening the circuit between the first and second terminals.

[0008] In this structure, by disconnecting the first and second terminals of the first sub-line, a detection signal for the high-frequency signal flowing through the main line can be extracted using the first sub-line. Furthermore, by short-circuiting the first and second terminals of the first sub-line, the coupling capacitance of the main line can be adjusted. This allows adjustment of the attenuation stage in the transmission characteristics of the main line, suppressing degradation of the transmission characteristics of the main line.

[0009] According to the present invention, in a directional coupler, the degradation of the transmission characteristics of high-frequency signals flowing through the main line can be suppressed. Attached Figure Description

[0010] Figure 1 This is a structural diagram of the directional coupler according to the first embodiment.

[0011] Figure 2 This is the equivalent circuit diagram of the directional coupler in the first embodiment.

[0012] Figure 3 This is a state diagram showing the first connection structure of the directional coupler in the first embodiment.

[0013] Figure 4 This is a graph representing an example of the simulation results of the transmission characteristics (S21) of the main line.

[0014] Figure 5 This is a state diagram showing the second connection structure of the directional coupler in the first embodiment.

[0015] Figure 6 This is a state diagram showing the third connection structure of the directional coupler in the first embodiment.

[0016] Figure 7 This is a state diagram showing the fourth connection structure of the directional coupler in the first embodiment.

[0017] Figure 8 This is a structural diagram of the directional coupler according to the second embodiment.

[0018] Figure 9 This is a state diagram showing the first connection structure of the directional coupler in the second embodiment.

[0019] Figure 10 This is a state diagram showing the second connection structure of the directional coupler in the second embodiment.

[0020] Figure 11 This is a structural diagram of the directional coupler according to the third embodiment.

[0021] Figure 12 This is a state diagram showing the first connection structure of the directional coupler in the third embodiment.

[0022] Figure 13 This is a state diagram showing the second connection structure of the directional coupler in the third embodiment.

[0023] Figure 14 This is a structural diagram of the directional coupler according to the fourth embodiment.

[0024] Figure 15 This is a state diagram showing the first connection structure of the directional coupler in the fourth embodiment.

[0025] Figure 16 This is a state diagram showing the second connection structure of the directional coupler in the fourth embodiment.

[0026] Figure 17 This is a structural diagram of the directional coupler according to the fifth embodiment.

[0027] Figure 18This is a state diagram showing the first connection structure of the directional coupler in the fifth embodiment.

[0028] Figure 19 This is a state diagram showing the second connection structure of the directional coupler in the fifth embodiment.

[0029] Figure 20 This is a structural diagram of the directional coupler according to the sixth embodiment.

[0030] Figure 21 This is a state diagram showing the first connection structure of the directional coupler according to the sixth embodiment.

[0031] Figure 22 This is a state diagram showing the second connection structure of the directional coupler in the sixth embodiment.

[0032] Figure 23 This is a structural diagram of the directional coupler according to the seventh embodiment.

[0033] Figure 24 This is a structural diagram of the directional coupler according to the eighth embodiment.

[0034] Figure 25 This is a structural diagram of the directional coupler according to the ninth embodiment.

[0035] Figure 26 This is a structural diagram of the directional coupler according to the tenth embodiment.

[0036] Figure 27 This is a graph representing an example of the simulation results of the transmission characteristics (S21) of the main line.

[0037] Figure 28 This is a structural diagram of the directional coupler according to the eleventh embodiment.

[0038] Figure 29 This is a structural diagram of the directional coupler according to the twelfth embodiment.

[0039] Figure 30A This is a top view of the secondary circuit of the directional coupler according to the thirteenth embodiment.

[0040] Figure 30B This is a top view of the main circuit of the directional coupler according to the thirteenth embodiment.

[0041] Figure 30C This is a top view of the secondary circuit of the directional coupler according to the thirteenth embodiment.

[0042] Figure 31 This is a cross-sectional view schematically showing the structure of the directional coupler according to the thirteenth embodiment.

[0043] Figure 32This is a structural diagram of the directional coupler according to the fourteenth embodiment. Detailed Implementation

[0044] [Summary of the Invention]

[0045] The present invention will now be described in summary.

[0046] One aspect of the present invention provides a directional coupler comprising: a main line, a first secondary line and a second secondary line configured to be electromagnetically coupled to the main line, and a first switching circuit connected between a first end and a second end of the first secondary line to switch short circuits and open circuits between the first end and the second end.

[0047] According to this structure, when the first and second terminals of the first sub-line are disconnected, a detection signal for a high-frequency signal flowing through the main line can be extracted using the first sub-line. Furthermore, when the first and second terminals of the first sub-line are short-circuited, the coupling capacitance to the main line can be adjusted. This allows adjustment of the attenuation stage in the transmission characteristics of the main line, suppressing degradation of the main line's transmission characteristics.

[0048] Alternatively, for example, one embodiment of the directional coupler of the present invention may also include a coupling terminal and a termination circuit connected to the first and second sub-lines, and a second switching circuit connected between the first and second sub-lines and the coupling terminal and the termination circuit.

[0049] According to this structure, the detection current flowing in any direction in either the first or second sub-line can be output from the coupling terminal. Therefore, stable coupling above the desired value can be achieved over a wide frequency band, and transmission loss in the main line can be suppressed.

[0050] Additionally, for example, in one embodiment of the directional coupler of the present invention, the second switching circuit may selectively switch the connection between the coupling terminal and the terminal circuit to either the first sub-line or the second sub-line.

[0051] This structure can prevent adverse effects such as electrical leakage and easily achieve the desired characteristics.

[0052] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the first switching circuit may short-circuit the first and second ends of the first sub-line when the second switching circuit connects the second sub-line to the coupling terminal and the terminal circuit.

[0053] This structure can prevent adverse effects such as electrical leakage to the terminal circuit and coupling terminals, and easily achieve the desired characteristics.

[0054] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the first switching circuit may disconnect the first and second ends of the first auxiliary line when the second switching circuit connects the first auxiliary line to the coupling terminal and the terminal circuit.

[0055] According to this structure, the detection current flowing in the first sub-circuit can be output from the coupling terminal.

[0056] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the second switching circuit may also have a first connection mode and a second connection mode, switching between the first connection mode and the second connection mode, wherein, in the first connection mode, the first end is connected to the coupling terminal and the second end is connected to the terminal circuit, and in the second connection mode, the second end is connected to the terminal circuit and the first end is connected to the coupling terminal.

[0057] According to this structure, a detection current flowing in any direction in the first sub-circuit can be output from the coupling terminal.

[0058] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the second switching circuit may have a third connection mode connecting the first terminal and the second terminal, switching between the first connection mode, the second connection mode and the third connection mode, and the short-circuit state of the first switching circuit is achieved through the third connection mode.

[0059] According to this structure, the detection current flowing in the first sub-circuit and the detection current flowing in the second sub-circuit can both be output from the coupling terminal by switching the connection method.

[0060] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the second switching circuit may include a first switch connected between the first end and the coupling terminal, a second switch connected between the second end and the coupling terminal, a third switch connected between the first end and the terminal circuit, and a fourth switch connected between the second end and the terminal circuit. The first switching circuit may be configured by a combination of the first switch and the second switch, or a combination of the third switch and the fourth switch.

[0061] According to this structure, a dedicated switch for controlling short circuits at both ends of the secondary line that is not used for detection can be omitted, thus reducing the circuit size. Furthermore, the number of switches connected to the secondary line that are not directly used for switching the output signal is reduced, improving the coupling in the desired frequency band and the suppression of transmission losses in the main line.

[0062] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the first switching circuit may be composed of a combination of a first switch and a second switch.

[0063] According to this structure, a dedicated switch for controlling short circuits at both ends of the secondary line that is not used for detection can be omitted, thus reducing the circuit size. Furthermore, the number of switches connected to the secondary line that are not directly used for switching the output signal is reduced, improving the coupling in the desired frequency band and the suppression of transmission losses in the main line.

[0064] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the second switching circuit may include a fifth switch that switches between short circuits and disconnections between the first switch and the coupling terminal, and between the second switch and the coupling terminal.

[0065] According to this structure, adverse effects such as electrical leakage to the coupling terminal and adverse effects from other circuits connected to the coupling terminal can be prevented, and the desired characteristics can be easily achieved.

[0066] Alternatively, for example, in one embodiment of the directional coupler of the present invention, when a third connection is achieved via a first switch and a second switch, a fifth switch may disconnect the first switch from the coupling terminal and the second switch from the coupling terminal.

[0067] According to this structure, the secondary line with its two ends short-circuited is not connected to the coupling terminal, which enables more accurate matching of the impedance between the secondary line of the output detection signal and the coupling terminal.

[0068] Alternatively, for example, in one embodiment of the directional coupler of the present invention, when the first connection is achieved by the first switch and the fourth switch, the fifth switch may short-circuit the first switch and the coupling terminal.

[0069] According to this structure, the detection current flowing in the first sub-circuit can be output from the coupling terminal.

[0070] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the first switching circuit may be composed of a combination of a third switch and a fourth switch.

[0071] According to this structure, a dedicated switch for controlling short circuits at both ends of the secondary line that is not used for detection can be omitted, thus reducing the circuit size. Furthermore, the number of switches connected to the secondary line that are not directly used for switching the output signal is reduced, improving the coupling in the desired frequency band and the suppression of transmission losses in the main line.

[0072] Alternatively, for example, in one embodiment of the directional coupler of the present invention, the second switching circuit may include a sixth switch that switches between short circuits and disconnections between the third switch and the terminal circuit, and between the fourth switch and the terminal circuit.

[0073] According to this structure, adverse effects such as electrical leakage to the coupling terminal and adverse effects from other circuits connected to the coupling terminal can be prevented, and the desired characteristics can be easily achieved.

[0074] Alternatively, for example, in one embodiment of the directional coupler of the present invention, when the third connection is achieved by the third switch and the fourth switch, the sixth switch may disconnect the third switch from the coupling terminal and the fourth switch from the coupling terminal.

[0075] According to this structure, the secondary line with its two ends short-circuited is not connected to the coupling terminal, which enables more accurate matching of the impedance between the secondary line of the output detection signal and the coupling terminal.

[0076] Alternatively, for example, in one embodiment of the directional coupler of the present invention, when the second connection method is achieved by the second switch and the third switch, the sixth switch may short-circuit the third switch with the coupling terminal.

[0077] According to this structure, the detection current flowing in the first sub-circuit can be output from the coupling terminal.

[0078] Hereinafter, a directional coupler according to embodiments of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, the embodiments described below represent specific examples of the present invention. Therefore, the numerical values, shapes, materials, constituent elements, arrangements of constituent elements, connection methods, steps, and order of steps shown in the following embodiments are merely examples and are not intended to limit the scope of the present invention. Therefore, constituent elements not described in the independent claims in the following embodiments are described as arbitrary constituent elements.

[0079] Furthermore, these figures are schematic diagrams and may not represent strictly accurate depictions of the structures. Therefore, for example, the scales may not be consistent across different figures. Additionally, substantially identical structures are labeled with the same reference numerals across different figures, and redundant descriptions are omitted or simplified.

[0080] [First Implementation Method]

[0081] The directional coupler of the first embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a structural diagram of the directional coupler according to the first embodiment. Figure 2 This is the equivalent circuit diagram of the directional coupler in the first embodiment.

[0082] like Figure 1 As shown, the directional coupler 10 includes a main line 20, a secondary line 31, a secondary line 32, a switching circuit 41, a switching circuit 42, a switch SW91, a switch SW92, an input / output terminal P21, an input / output terminal P22, a coupling terminal Pcp, and a terminal circuit 80.

[0083] Main circuit 20, secondary circuit 31, and secondary circuit 32 are formed, for example, by conductor patterns formed on an insulating substrate. Switching circuit 41, switching circuit 42, switch SW91, switch SW92, and terminal circuit 80 are formed, for example, by mounting-type electronic components mounted on an insulating substrate and conductor patterns formed on an insulating substrate. Input / output terminals P21, P22, and coupling terminals Pcp are formed, for example, by terminal conductor patterns formed on an insulating substrate.

[0084] The main line 20 is a shape (e.g., linear) that extends in a specified direction. One end of the main line 20 is connected to the input / output terminal P21, and the other end of the main line 20 is connected to the input / output terminal P22.

[0085] The secondary line 31 is configured to electromagnetically couple with the primary line 20. For example, the secondary line 31 extends parallel to the primary line 20 at a predetermined interval. In this case, the shape of the secondary line 31 and its configuration relative to the primary line 20 are determined to achieve the desired coupling degree with respect to the primary line 20 in the first frequency band.

[0086] The secondary line 32 is configured to electromagnetically couple with the primary line 20. For example, the secondary line 32 extends parallel to the primary line 20 at a predetermined interval. In this case, the shape of the secondary line 32 and its configuration relative to the primary line 20 are determined to achieve the desired coupling degree with respect to the primary line 20 in the second frequency band.

[0087] The second frequency band is not exactly the same as the first frequency band. In other words, the second frequency band is different from the first frequency band. For example, the second frequency band is a band closer to the high-frequency side than the first frequency band. In this case, such as... Figure 1 As shown, the length of the parallel line 32 with the main line 20 is shorter than the length of the parallel line 31 with the main line 20. For example, the second frequency band is a frequency band above 1.5 GHz with a specified bandwidth. The first frequency band is a frequency band below 1.5 GHz with a specified bandwidth. Furthermore, this first and second frequency bands are just examples and are not limited to this.

[0088] Sub-line 31 has an end portion 311 at one end in the extending direction and an end portion 312 at the other end in the extending direction. Sub-line 32 has an end portion 321 at one end in the extending direction and an end portion 322 at the other end in the extending direction. Either of these sub-lines 31 and 32 corresponds to the "first sub-line" of the present invention, and the other corresponds to the "second sub-line" of the present invention. Furthermore, when sub-line 31 is the first sub-line, end portion 311 corresponds to the "first end" of the present invention, and end portion 312 corresponds to the "second end" of the present invention. When sub-line 32 is the first sub-line, end portion 321 corresponds to the "first end" of the present invention, and end portion 322 corresponds to the "second end" of the present invention. Alternatively, when sub-line 31 is the first sub-line, end portion 312 may correspond to the "first end" of the present invention, and end portion 311 may correspond to the "second end" of the present invention. Also, when sub-line 32 is the first sub-line, end portion 322 may correspond to the "first end" of the present invention, and end portion 321 may correspond to the "second end" of the present invention.

[0089] The switching circuit 41 includes switches SW11, SW12, SW13, and SW14. Switch SW11 is connected between end 311 of the secondary line 31 and the coupling terminal Pcp, switching between short-circuiting and opening the connection between end 311 and the coupling terminal Pcp. Switch SW12 is connected between end 312 of the secondary line 31 and the coupling terminal Pcp, switching between short-circuiting and opening the connection between end 312 and the coupling terminal Pcp. Switch SW13 is connected between end 311 of the secondary line 31 and the terminal circuit 80, switching between short-circuiting and opening the connection between end 311 and the terminal circuit 80. Switch SW14 is connected between end 312 of the secondary line 31 and the terminal circuit 80, switching between short-circuiting and opening the connection between end 312 and the terminal circuit 80.

[0090] The coupling terminal Pcp side of switch SW11 and the coupling terminal Pcp side of switch SW12 are connected to each other. The terminal circuit 80 side of switch SW13 and the terminal circuit 80 side of switch SW14 are connected to each other. When the sub-line 31 is the "first sub-line", switches SW11, SW12, SW13 and SW14 correspond to the "first switch", "second switch", "third switch" and "fourth switch" of the present invention, respectively.

[0091] The switching circuit 42 includes switches SW21, SW22, SW23, and SW24. Switch SW21 is connected between end 321 of the secondary line 32 and the coupling terminal Pcp, switching between short-circuiting and opening the connection between end 321 and the coupling terminal Pcp. Switch SW22 is connected between end 322 of the secondary line 31 and the coupling terminal Pcp, switching between short-circuiting and opening the connection between end 322 and the coupling terminal Pcp. Switch SW23 is connected between end 321 of the secondary line 32 and the terminal circuit 80, switching between short-circuiting and opening the connection between end 321 and the terminal circuit 80. Switch SW24 is connected between end 322 of the secondary line 32 and the terminal circuit 80, switching between short-circuiting and opening the connection between end 322 and the terminal circuit 80.

[0092] The coupling terminal Pcp side of switch SW21 and the coupling terminal Pcp side of switch SW22 are connected to each other. The terminal circuit 80 side of switch SW23 and the terminal circuit 80 side of switch SW24 are connected to each other. When the sub-line 32 is the "first sub-line", switches SW21, SW22, SW23 and SW24 correspond to the "first switch", "second switch", "third switch" and "fourth switch" of the present invention, respectively.

[0093] Furthermore, in the directional coupler 10, the "first switch," "second switch," "third switch," and "fourth switch" are configured on both sides of the secondary line 31 and the secondary line 32, but the "first switch," "second switch," "third switch," and "fourth switch" may also be configured on only one side of the secondary line 31 or the secondary line 32. Switching circuit 41 and switching circuit 42 correspond to the "second switching circuit" of the present invention.

[0094] Switch SW91 is connected between end 311 and end 312 of the secondary line 31. Switch SW91 switches between short circuit and open circuit between end 311 and end 312. When the secondary line 31 is the "first secondary line", switch SW91 corresponds to the "first switching circuit" of the present invention.

[0095] Switch SW92 is connected between end 321 and end 322 of the secondary line 32. Switch SW92 switches the short circuit and open circuit between end 321 and end 322. When the secondary line 32 is the "first secondary line", switch SW92 corresponds to the "first switching circuit" of the present invention.

[0096] Furthermore, in the directional coupler 10, the "first switching circuit" is configured on both the secondary line 31 and the secondary line 32, but the "first switching circuit" may also be configured on either the secondary line 31 or the secondary line 32.

[0097] The terminal circuit 80 includes a variable resistor Rt and a variable capacitor Ct. The parallel circuit of the variable resistor Rt and the variable capacitor Ct connects switches SW13, SW14, SW23, and SW24 to a reference potential.

[0098] In such a structure, such as Figure 2 As shown, a coupling capacitor C231 is generated between the main line 20 (inductor L20) and the secondary line 31 (inductor L31). Additionally, a coupling capacitor C232 is generated between the main line 20 (inductor L20) and the secondary line 32 (inductor L32). In other words, by adjusting the coupling capacitor C231, the directional coupler 10 can adjust the electromagnetic coupling between the main line 20 and the secondary line 31, and can extract a coupled signal of the desired level to the first secondary line 31. Furthermore, by adjusting the coupling capacitor C232, the directional coupler 10 can adjust the electromagnetic coupling between the main line 20 and the secondary line 32, and can extract a coupled signal of the desired level to the second secondary line 32.

[0099] [Connection structure of directional coupler 10]

[0100] The directional coupler 10, constructed with the above structure, outputs a detection signal for the high-frequency signal flowing through the main line 20 from the coupling terminal Pcp through various connection structures shown below.

[0101] (1-1) Structure for outputting a detection signal from the coupling terminal Pcp that flows from end 322 to end 321 of the sub-line 32.

[0102] Figure 3 This is a state diagram showing the first connection structure of the directional coupler in the first embodiment.

[0103] like Figure 3 As shown, switches SW21 and SW24 of switch circuit 42 are short-circuited. Switches SW22 and SW23 of switch circuit 42 are open. Therefore, end 321 of secondary line 32 is connected to the coupling terminal Pcp, but not to the terminal circuit 80. End 322 of secondary line 32 is connected to the terminal circuit 80, but not to the coupling terminal Pcp. Switch SW92 is open.

[0104] Switches SW11, SW12, SW13, and SW14 in switch circuit 41 are disconnected.

[0105] According to this structure, the directional coupler 10 outputs a detection signal from the coupling terminal Pcp that is excited in the secondary line 32 and flows from the end 322 side to the end 321 side. Furthermore, the so-called detection signal that is excited in the secondary line 32 and flows from the end 322 side to the end 321 side is a signal corresponding to the high-frequency signal flowing in the main line 20 from the input / output terminal P21 side to the input / output terminal P22 side.

[0106] At this time, switch SW91 is short-circuited. As a result, ends 311 and 312 of the secondary line 31 are connected. By implementing this structure, the capacitive component of the secondary line 31 connected to the main line 20 in the equivalent circuit suppresses the influence of the inductance L31 of the secondary line 31, which is different from the structure where ends 311 and 312 of the secondary line 31 are not connected (the conventional structure).

[0107] Therefore, the frequency of the parallel resonance formed by the inductance L20 of the main line 20 and the capacitance of the secondary line 31 changes. This allows adjustment of the position of the attenuation pole generated at a specified frequency in the transmission characteristics of the main line 20.

[0108] Figure 4 This is a graph illustrating an example of the simulation results for the transmission characteristics (S21) of the main line. Figure 4 In the diagram, solid lines represent the characteristics of the structure described in this application, while dashed lines represent the characteristics of comparison structure 1. The comparison structure does not possess the switch SW91 described in this invention.

[0109] like Figure 4 As shown, by short-circuiting ends 311 and 312 of the secondary line 31 using switch SW91, the specified frequency of the main line (in) can be achieved. Figure 4 In the case of approximately 5.2 [GHz], the attenuation electrode is directed towards the high-frequency side (in... Figure 4 In the case of 7.0 [GHz], it moves closer to the high-frequency side.

[0110] Therefore, the main line 20 can suppress significant degradation of transmission characteristics over a wider frequency band, achieving low-loss transmission characteristics. Thus, the directional coupler 10 can suppress transmission loss of high-frequency signals flowing in the main line 20 over a wider frequency band and obtain a detection signal in the desired frequency band.

[0111] Furthermore, in this structure, the coupling capacitance on the side of the sub-line 31 relative to the main line 20 can be adjusted simply by short-circuiting the switch SW91. That is, it is not easy to physically change the coupling degree between the sub-line 31, which does not output a detection signal, and the main line 20, and it is even more difficult when the main line 20 and the sub-line 31 are formed on the same insulating substrate. However, by using this structure, the coupling capacitance on the side of the sub-line 31 relative to the main line 20 can be adjusted even without changing the physical positional relationship between the main line 20 and the sub-line 31.

[0112] (1-2) The method of outputting the detection signal from the coupling terminal Pcp from the end 321 side to the end 322 side of the sub-line 32.

[0113] Figure 5 This is a state diagram showing the second connection structure of the directional coupler in the first embodiment.

[0114] Switches SW22 and SW23 in switching circuit 42 are short-circuited. Switches SW21 and SW24 in switching circuit 42 are open. Therefore, end 322 of secondary line 32 is connected to the coupling terminal Pcp, but not to the terminal circuit 80. End 321 of secondary line 32 is connected to the terminal circuit 80, but not to the coupling terminal Pcp. Switch SW92 is open.

[0115] Switches SW11, SW12, SW13, and SW14 in switch circuit 41 are disconnected.

[0116] According to this structure, the directional coupler 10 outputs a detection signal from the coupling terminal Pcp that is excited in the secondary line 32 and flows from the end 321 side to the end 322 side. Furthermore, the so-called detection signal that is excited in the secondary line 32 and flows from the end 321 side to the end 322 side is a signal corresponding to the high-frequency signal flowing in the main line 20 from the input / output terminal P22 side to the input / output terminal P21 side (a reflected signal of the high-frequency signal flowing in the main line 20 from the input / output terminal P21 side to the input / output terminal P22 side).

[0117] At this time, switch SW91 is short-circuited. As a result, end 311 of the secondary line 31 is connected to end 312. By implementing this structure, in the same manner as (1-1), the main line 20 can suppress significant degradation of transmission characteristics over a wider frequency band and achieve low-loss transmission characteristics.

[0118] Furthermore, the directional coupler 10 can switch between mode (1-1) and mode (1-2). Therefore, the directional coupler 10 can output a detection current flowing in any direction in the secondary line 32 from the coupling terminal Pcp. That is, within the frequency band detectable by the secondary line 32, the directional coupler 10 can output detection signals for both the high-frequency signal flowing from input / output terminal P21 to input / output terminal P22 in the main line 20 and the high-frequency signal flowing from input / output terminal P22 to input / output terminal P21 in the main line 20. In this case, the directional coupler 10, as described above, can achieve low-loss transmission characteristics over a wider frequency band.

[0119] (1-3) The method of outputting the detection signal from the coupling terminal Pcp from the end 312 side to the end 311 side of the sub-line 31.

[0120] Figure 6 This is a state diagram showing the third connection structure of the directional coupler in the first embodiment.

[0121] Switches SW11 and SW14 in switching circuit 41 are short-circuited. Switches SW12 and SW13 in switching circuit 41 are open. Therefore, end 311 of secondary line 31 is connected to the coupling terminal Pcp, but not to the terminal circuit 80. End 312 of secondary line 31 is connected to the terminal circuit 80, but not to the coupling terminal Pcp. Switch SW91 is open.

[0122] Switches SW21, SW22, SW23, and SW24 in switch circuit 42 are disconnected.

[0123] According to this structure, the directional coupler 10 outputs a detection signal from the coupling terminal Pcp that excites a flow from the end 312 side to the end 311 side in the secondary line 31. Furthermore, the so-called detection signal that is excited in the secondary line 31 and flows from the end 312 side to the end 311 side is a signal corresponding to the high-frequency signal flowing from the input / output terminal P21 side to the input / output terminal P22 side in the main line 20.

[0124] At this time, switch SW92 is short-circuited. As a result, end 321 of the secondary line 32 is connected to end 322. By implementing this structure, similarly to (1-1) and (1-2), the main line 20 can suppress significant degradation of transmission characteristics over a wider frequency band and achieve low-loss transmission characteristics.

[0125] (1-4) The method of outputting the detection signal from the coupling terminal Pcp from the end 311 side to the end 312 side of the sub-line 31

[0126] Figure 7This is a state diagram showing the fourth connection structure of the directional coupler in the first embodiment.

[0127] Switches SW12 and SW13 in switching circuit 41 are short-circuited. Switches SW11 and SW14 in switching circuit 41 are open. Therefore, end 312 of secondary line 31 is connected to the coupling terminal Pcp, but not to the terminal circuit 80. End 311 of secondary line 31 is connected to the terminal circuit 80, but not to the coupling terminal Pcp. Switch SW91 is open.

[0128] Switches SW21, SW22, SW23, and SW24 in switch circuit 42 are disconnected.

[0129] According to this structure, the directional coupler 10 outputs a detection signal from the coupling terminal Pcp that is excited in the secondary line 31 and flows from the end 311 side to the end 312 side. Furthermore, the so-called detection signal that is excited in the secondary line 31 and flows from the end 311 side to the end 312 side is a signal corresponding to the high-frequency signal flowing in the main line 20 from the input / output terminal P22 side to the input / output terminal P21 side (a reflected signal of the high-frequency signal flowing in the main line 20 from the input / output terminal P21 side to the input / output terminal P22 side).

[0130] At this time, switch SW92 is short-circuited. As a result, end 321 of the secondary line 32 is connected to end 322. By implementing this structure, similarly to (1-1), (1-2), and (1-3), the main line 20 can suppress significant degradation of transmission characteristics over a wider frequency band and achieve low-loss transmission characteristics.

[0131] Furthermore, the directional coupler 10 can switch between modes (1-3) and (1-4). Thus, the directional coupler 10 can output a detection current flowing in any direction in the secondary line 31 from the coupling terminal Pcp. That is, within the frequency band detectable by the secondary line 31, the directional coupler 10 can output detection signals for both the high-frequency signal flowing from input / output terminal P21 to input / output terminal P22 in the main line 20 and the high-frequency signal flowing from input / output terminal P22 to input / output terminal P21 in the main line 20. In this case, the directional coupler 10, as described above, can achieve low-loss transmission characteristics over a wider frequency band.

[0132] Furthermore, the directional coupler 10 can switch between modes (1-1), (1-2), (1-3), and (1-4). Thus, the directional coupler 10 can extract bidirectional detection signals from the main line 20 through multiple sub-lines 31 and 32 and output them from the coupling terminal Pcp.

[0133] As described above, the detection signal has a different frequency band in sub-line 31 and sub-line 32. Therefore, the directional coupler 10 obtains a detection signal with a wider frequency band and is able to suppress the degradation of transmission characteristics in the main line 20.

[0134] Here, for example, the frequency band detected by sub-lines 31 and 32 is achieved through a sub-line. In this case, a stable coupling degree cannot be obtained near the desired value in a wider frequency band. That is, there are frequencies where the coupling amount between the main line and the sub-line can only be obtained at values ​​greater than or less than the desired value, or the coupling amount between the main line and the sub-line decreases throughout the detected frequency band.

[0135] However, the directional coupler 10 uses multiple sub-lines 31, 32, each responsible for a different frequency. Therefore, the directional coupler 10 can achieve stable coupling near the desired value in a wider frequency band that cannot be achieved through a single sub-line.

[0136] At this point, if the number of secondary lines increases, the coupling capacitance to the main line 20 increases. Due to this parallel resonance, as described above, the transmission loss of the main line 20 deteriorates at a predetermined frequency. However, in the directional coupler 10, by short-circuiting the two ends of the secondary lines not used for signal detection output, as described above, the coupling capacitance can be adjusted, and the frequency at which the transmission loss of the main line 20 deteriorates can be shifted. Therefore, the directional coupler 10 achieves a stable coupling degree above the desired value over a wider frequency band and can suppress the transmission loss of the main line 20.

[0137] [Second Implementation]

[0138] The directional coupler of the second embodiment of the present invention will be described with reference to the accompanying drawings. Figure 8 This is a structural diagram of the directional coupler according to the second embodiment.

[0139] The second embodiment of the directional coupler 10A differs from the first embodiment in that it includes switching circuits 41A and 42A, and physically omits switches SW91 and SW92. In general, the directional coupler 10A functions as switch SW91 in switching circuit 41A and switch SW92 in switching circuit 42A. The other structures of the directional coupler 10A are the same as those of the directional coupler 10, and descriptions of identical locations are omitted.

[0140] The switching circuit 41A includes switches SW11, SW12, SW13, and SW14. Switch SW11 is connected between end 311 of the secondary line 31 and the coupling terminal Pcp, switching between short-circuiting and opening the connection between end 311 and the coupling terminal Pcp. Switch SW12 is connected between end 312 of the secondary line 31 and the coupling terminal Pcp, switching between short-circuiting and opening the connection between end 312 and the coupling terminal Pcp. Switch SW13 is connected between end 311 of the secondary line 31 and the terminal circuit 80, switching between short-circuiting and opening the connection between end 311 and the terminal circuit 80. Switch SW14 is connected between end 312 of the secondary line 31 and the terminal circuit 80, switching between short-circuiting and opening the connection between end 312 and the terminal circuit 80.

[0141] The coupling terminal Pcp side of switch SW11 and the coupling terminal Pcp side of switch SW12 are connected to each other. The terminal circuit 80 side of switch SW13 and the terminal circuit 80 side of switch SW14 are connected. When the sub-line 31 is the "first sub-line", switches SW11, SW12, SW13 and SW14 correspond to the "first switch", "second switch", "third switch" and "fourth switch" of the present invention, respectively.

[0142] The switching circuit 42A includes switches SW21, SW22, SW23, and SW24. Switch SW21 is connected between end 321 of the secondary line 32 and the coupling terminal Pcp, switching between short-circuiting and opening the connection between end 321 and the coupling terminal Pcp. Switch SW22 is connected between end 322 of the secondary line 31 and the coupling terminal Pcp, switching between short-circuiting and opening the connection between end 322 and the coupling terminal Pcp. Switch SW23 is connected between end 321 of the secondary line 32 and the terminal circuit 80, switching between short-circuiting and opening the connection between end 321 and the terminal circuit 80. Switch SW24 is connected between end 322 of the secondary line 32 and the terminal circuit 80, switching between short-circuiting and opening the connection between end 322 and the terminal circuit 80.

[0143] The coupling terminal Pcp side of switch SW21 and the coupling terminal Pcp side of switch SW22 are connected to each other. The terminal circuit 80 side of switch SW23 and the terminal circuit 80 side of switch SW24 are connected. When the sub-line 32 is the "first sub-line", switches SW21, SW22, SW23 and SW24 correspond to the "first switch", "second switch", "third switch" and "fourth switch" of the present invention, respectively.

[0144] [Connection structure of directional coupler 10A]

[0145] The directional coupler 10A, constructed with the above structure, outputs a detection signal for the high-frequency signal flowing through the main line 20 from the coupling terminal Pcp through various connection structures shown below.

[0146] (2-1) The structure that controls the switch connected to the coupling terminal Pcp to short-circuit both ends of the secondary circuit.

[0147] Figure 9 This is a state diagram showing the first connection structure of the directional coupler in the second embodiment. Figure 9 This describes the structure from which a detection signal is output from the coupling terminal Pcp and flows from end 322 to end 321 of the sub-line 32.

[0148] like Figure 9 As shown, switches SW21 and SW24 of switch circuit 42A are short-circuited. Switches SW22 and SW23 of switch circuit 42A are disconnected. Therefore, end 321 of secondary line 32 is connected to the coupling terminal Pcp and not to the terminal circuit 80. End 322 of secondary line 32 is connected to the terminal circuit 80 and not to the coupling terminal Pcp.

[0149] According to this structure, the directional coupler 10A outputs a detection signal from the coupling terminal Pcp that is excited in the sub-line 32 and flows from the end 322 side to the end 321 side.

[0150] Switches SW11 and SW12 in switch circuit 41A are short-circuited. Switches SW13 and SW14 in switch circuit 41A are open.

[0151] According to this structure, end 311 of the secondary line 31 is connected to end 312. That is, a circuit equivalent to the circuit that short-circuits the switch SW91 in the first embodiment (corresponding to (1-1) in the first embodiment) can be realized.

[0152] Furthermore, although the illustrations and detailed descriptions are omitted, the following methods can also be used to achieve short circuits at both ends of the sub-line 31 and at both ends of the sub-line 32: outputting a detection signal flowing from end 321 to end 322 of the sub-line 32 from the coupling terminal Pcp (corresponding to method (1-2) of the first embodiment), outputting a detection signal flowing from end 312 to end 311 of the sub-line 31 from the coupling terminal Pcp (corresponding to method (1-3) of the first embodiment), and outputting a detection signal flowing from end 311 to end 312 of the sub-line 31 from the coupling terminal Pcp (corresponding to method (1-4) of the first embodiment).

[0153] Thus, the directional coupler 10A achieves stable coupling near the desired value over a wide frequency band and can suppress transmission loss of the main line 20.

[0154] Furthermore, in the directional coupler 10A, a dedicated switch for controlling short circuits at both ends of the secondary line that is not used for detection can be omitted, reducing the circuit size. Additionally, the number of switches connected to the secondary line that are not directly used for switching the output signal is reduced, improving the coupling efficiency in the desired frequency band and the suppression of transmission losses in the main line 20.

[0155] Furthermore, in the manner described in (2-1), the secondary line with its two ends short-circuited is not connected to the terminal circuit 80. Therefore, the directional coupler 10A can prevent adverse effects such as electrical leakage to the terminal circuit 80 caused by the connection between the terminal circuit 80 and the secondary line with its two ends short-circuited, easily achieving the desired characteristics.

[0156] (2-2) The structure that controls the switch connected to the terminal circuit 80 to short-circuit both ends of the secondary line.

[0157] Figure 10 This is a state diagram showing the second connection structure of the directional coupler in the second embodiment. Figure 10 and Figure 9 Similarly, this represents the structure from which the detection signal flows from end 322 to end 321 of the sub-line 32, output from the coupling terminal Pcp.

[0158] like Figure 10 As shown, switches SW21 and SW24 of switch circuit 42A are short-circuited. Switches SW22 and SW23 of switch circuit 42A are disconnected. Therefore, end 321 of secondary line 32 is connected to the coupling terminal Pcp and not to the terminal circuit 80. End 322 of secondary line 32 is connected to the terminal circuit 80 and not to the coupling terminal Pcp.

[0159] According to this structure, the directional coupler 10 outputs a detection signal from the coupling terminal Pcp that is excited in the sub-line 32 and flows from the end 322 side to the end 321 side.

[0160] Switches SW13 and SW14 in switch circuit 41A are short-circuited. Switches SW11 and SW12 in switch circuit 41A are open.

[0161] According to this structure, end 311 of the secondary line 31 is connected to end 312. That is, a circuit equivalent to the circuit that short-circuits the switch SW91 in the first embodiment (corresponding to (1-1) in the first embodiment) can be realized.

[0162] Furthermore, although the illustrations and detailed descriptions are omitted, the following methods can also be used to achieve short circuits at both ends of the sub-line 31 and at both ends of the sub-line 32: outputting a detection signal flowing from end 321 to end 322 of the sub-line 32 from the coupling terminal Pcp (corresponding to method (1-2) of the first embodiment), outputting a detection signal flowing from end 312 to end 311 of the sub-line 31 from the coupling terminal Pcp (corresponding to method (1-3) of the first embodiment), and outputting a detection signal flowing from end 311 to end 312 of the sub-line 31 from the coupling terminal Pcp (corresponding to method (1-4) of the first embodiment).

[0163] Therefore, the directional coupler 10A can achieve the same effect as the above-mentioned (2-1) method through (2-2).

[0164] Furthermore, in the manner described in (2-2), the secondary line with its two ends short-circuited is not connected to the coupling terminal Pcp. Therefore, the directional coupler 10A can prevent adverse effects such as electrical leakage to the coupling terminal Pcp caused by the connection between the coupling terminal Pcp and the secondary line with its two ends short-circuited, as well as adverse effects caused by other circuits connected to the coupling terminal Pcp, easily achieving the desired characteristics. Additionally, in the manner described in (2-2), by preventing the secondary line with its two ends short-circuited from being connected to the coupling terminal Pcp, the impedance of the secondary line outputting the detection signal and the coupling terminal Pcp can be matched with higher precision.

[0165] [Third Implementation Method]

[0166] The directional coupler of the third embodiment of the present invention will be described with reference to the accompanying drawings. Figure 11 This is a structural diagram of the directional coupler according to the third embodiment.

[0167] The directional coupler 10B of the third embodiment differs from the directional coupler 10A of the second embodiment in that a switching circuit 491 is added. The other structures of the directional coupler 10B are the same as those of the directional coupler 10A, and descriptions of identical locations are omitted.

[0168] Switching circuit 491 is connected between switching circuit 41B and coupling terminal Pcp, and between switching circuit 42B and coupling terminal Pcp. Switching circuit 41B has the same structure as switching circuit 41A. Switching circuit 42B has the same structure as switching circuit 42A. Switching circuit 491 functions as part of the "second switching circuit" of the present invention.

[0169] More specifically, the switching circuit 491 includes switches SW41 and SW42. When the secondary line 31 is the "first secondary line", switch SW41 corresponds to the "fifth switch" of the present invention, and when the secondary line 32 is the "first secondary line", switch SW42 corresponds to the "fifth switch" of the present invention.

[0170] Switch SW41 is connected between switch SW11 and coupling terminal Pcp in switch circuit 41B, and between switch SW12 and coupling terminal Pcp, switching them between short circuit and open circuit. Switch SW42 is connected between switch SW21 and coupling terminal Pcp in switch circuit 42B, and between switch SW22 and coupling terminal Pcp, switching them between short circuit and open circuit.

[0171] [Connection structure of directional coupler 10B]

[0172] The directional coupler 10B, constructed with the above structure, outputs a detection signal for the high-frequency signal flowing in the main line 20 from the coupling terminal Pcp through various connection structures shown below.

[0173] (3-1) Structure for outputting a detection signal from the coupling terminal Pcp that flows from end 322 to end 321 of the sub-line 32.

[0174] Figure 12 This is a state diagram showing the first connection structure of the directional coupler in the third embodiment.

[0175] like Figure 12 As shown, switches SW21 and SW24 of switch circuit 42B are short-circuited. Switches SW22 and SW23 of switch circuit 42B are disconnected. Therefore, end 321 of secondary line 32 is connected to switch SW42 of switch circuit 491, but not to terminal circuit 80. End 322 of secondary line 32 is connected to terminal circuit 80, but not to coupling terminal Pcp.

[0176] Switch SW42 of switching circuit 491 is short-circuited. As a result, end 321 of sub-line 32 is connected to coupling terminal Pcp via switches SW21 and SW42.

[0177] According to this structure, the directional coupler 10B outputs a detection signal from the coupling terminal Pcp that is excited in the sub-line 32 and flows from the end 322 side to the end 321 side.

[0178] Switches SW11 and SW12 in switch circuit 41B are short-circuited. Switches SW13 and SW14 in switch circuit 41B are open.

[0179] According to this structure, ends 311 and 312 of the sub-line 31 are connected. That is, a circuit equivalent to the circuit that short-circuits the switch SW91 in the first embodiment (corresponding to (1-1) in the first embodiment) can be realized.

[0180] Switch SW41 of switching circuit 491 is turned off. As a result, switches SW11 and SW12 of switching circuit 41B, and consequently sub-line 31, are not connected to coupling terminal Pcp.

[0181] Furthermore, although the illustrations and detailed descriptions are omitted, for the manner in which the detection signal flows from the end 321 side to the end 322 side of the sub-line 32 is output from the coupling terminal Pcp (corresponding to the manner in (1-2) of the first embodiment), the ends 311 and 312 of the sub-line 31 are also connected in the same way.

[0182] Thus, the directional coupler 10B achieves a stable coupling degree above the desired value over a wide frequency band and can suppress the transmission loss of the main line 20.

[0183] Furthermore, in the manner described in (3-1), the secondary line 31, with its two ends short-circuited, is not connected to the coupling terminal Pcp. Therefore, the directional coupler 10B can prevent adverse effects such as electrical leakage to the coupling terminal Pcp caused by the connection of the coupling terminal Pcp to the secondary line 31 with its two ends short-circuited, as well as adverse effects caused by other circuits connected to the coupling terminal Pcp, easily achieving the desired characteristics. Additionally, in the manner described in (3-1), by not connecting the secondary line 31, with its two ends short-circuited, to the coupling terminal Pcp, the impedance of the secondary line 32 outputting the detection signal and the coupling terminal Pcp can be matched with higher precision.

[0184] (3-2) Structure for outputting a detection signal from the coupling terminal Pcp that flows from end 312 to end 311 of the secondary line 31.

[0185] Figure 13 This is a state diagram showing the second connection structure of the directional coupler in the third embodiment.

[0186] like Figure 13 As shown, switches SW11 and SW14 of switch circuit 41B are short-circuited. Switches SW12 and SW13 of switch circuit 41B are disconnected. Therefore, end 311 of secondary line 31 is connected to switch SW41 of switch circuit 491, but not to terminal circuit 80. End 312 of secondary line 31 is connected to terminal circuit 80, but not to coupling terminal Pcp.

[0187] Switch SW41 of switching circuit 491 is short-circuited. As a result, end 311 of sub-line 31 is connected to coupling terminal Pcp via switches SW11 and SW41.

[0188] According to this structure, the directional coupler 10B outputs a detection signal that is excited in the sub-line 31 and flows from the end 312 side to the end 311 side from the coupling terminal Pcp.

[0189] Switches SW21 and SW22 in switch circuit 42B are short-circuited. Switches SW23 and SW24 in switch circuit 42B are open.

[0190] According to this structure, ends 321 and 322 of the secondary line 32 are connected. That is, a circuit equivalent to the circuit that short-circuits the switch SW92 in the first embodiment (corresponding to (1-3) in the first embodiment) can be realized.

[0191] Switch SW42 of switch circuit 491 is turned off. As a result, switches SW21 and SW22 of switch circuit 42B, and consequently sub-line 32, are not connected to coupling terminal Pcp.

[0192] Furthermore, although the illustrations and detailed descriptions are omitted, the ends 321 and 322 of the sub-line 32 are also connected in the same way for the detection signal flowing from the end 311 side to the end 312 side of the sub-line 31 to be output from the coupling terminal Pcp (corresponding to the mode of (1-4) in the first embodiment).

[0193] Thus, the directional coupler 10B achieves a stable coupling degree above the desired value in a wide frequency band and can suppress the transmission loss of the main line 20.

[0194] Furthermore, in the manner described in (3-2), the secondary line 32, with its two ends short-circuited, is not connected to the coupling terminal Pcp. Therefore, the directional coupler 10B can prevent adverse effects such as electrical leakage to the coupling terminal Pcp caused by the connection between the coupling terminal Pcp and the secondary line 32 with its two ends short-circuited, as well as adverse effects caused by other circuits connected to the coupling terminal Pcp, easily achieving the desired characteristics. Additionally, in the manner described in (3-2), by not connecting the secondary line 32, with its two ends short-circuited, to the coupling terminal Pcp, the impedance of the secondary line 31 outputting the detection signal and the coupling terminal Pcp can be matched with higher precision.

[0195] [Fourth Implementation Method]

[0196] The directional coupler of the fourth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 14 This is a structural diagram of the directional coupler according to the fourth embodiment.

[0197] The directional coupler 10C of the fourth embodiment differs from the directional coupler 10A of the second embodiment in that a switching circuit 492 is added. The other structures of the directional coupler 10C are the same as those of the directional coupler 10A, and descriptions of identical locations are omitted.

[0198] Switching circuit 492 is connected between switching circuit 41C and terminal circuit 80, and between switching circuit 42C and terminal circuit 80. Switching circuit 41C has the same structure as switching circuit 41A. Switching circuit 42C has the same structure as switching circuit 42A. Switching circuit 492 functions as part of the "second switching circuit" of the present invention.

[0199] More specifically, the switching circuit 492 includes switches SW43 and SW44. When the secondary line 31 is the "first secondary line", switch SW43 corresponds to the "sixth switch" of the present invention, and when the secondary line 32 is the "first secondary line", switch SW44 corresponds to the "sixth switch" of the present invention.

[0200] Switch SW43 is connected between switch SW13 and terminal circuit 80 in switch circuit 41C, and between switch SW14 and terminal circuit 80, switching them between short circuit and open circuit. Switch SW44 is connected between switch SW23 and terminal circuit 80 in switch circuit 42C, and between switch SW24 and terminal circuit 80, switching them between short circuit and open circuit.

[0201] (4-1) Structure for outputting a detection signal from the coupling terminal Pcp that flows from end 322 to end 321 of the sub-line 32.

[0202] Figure 15 This is a state diagram showing the first connection structure of the directional coupler in the fourth embodiment.

[0203] like Figure 15 As shown, switches SW21 and SW24 of switch circuit 42C are short-circuited. Switches SW22 and SW23 of switch circuit 42C are disconnected. Therefore, end 321 of secondary line 32 is connected to the coupling terminal Pcp, but not to switch SW44 of switch circuit 492. End 322 of secondary line 32 is connected to switch SW44 of switch circuit 492, but not to coupling terminal Pcp.

[0204] Switch SW44 of switching circuit 492 is short-circuited. As a result, end 322 of sub-line 32 is connected to terminal circuit 80 via switches SW24 and SW44.

[0205] According to this structure, the directional coupler 10C outputs a detection signal from the coupling terminal Pcp that is excited in the sub-line 32 and flows from the end 322 side to the end 321 side.

[0206] Switches SW13 and SW14 in switch circuit 41C are short-circuited.

[0207] According to this structure, ends 311 and 312 of the sub-line 31 are connected. That is, a circuit equivalent to the circuit that short-circuits the switch SW91 in the first embodiment (corresponding to (1-1) in the first embodiment) can be realized.

[0208] Switch SW43 of switch circuit 492 is turned off. As a result, switches SW13 and SW14 of switch circuit 41C, and consequently sub-line 31, are not connected to terminal circuit 80.

[0209] Additionally, switches SW11 and SW12 in the switching circuit 41C are disconnected. Consequently, the secondary line 31 and the coupling terminal Pcp are not connected.

[0210] Furthermore, although the illustrations and detailed descriptions are omitted, the ends 311 and 312 of the sub-line 31 are also connected in the same way for the detection signal flowing from the end 321 side to the end 322 side of the sub-line 32 to be output from the coupling terminal Pcp (corresponding to the (1-2) method of the first embodiment).

[0211] Thus, the directional coupler 10C achieves a stable coupling degree above the desired value in a wide frequency band and can suppress the transmission loss of the main line 20.

[0212] Furthermore, in the manner described in (4-1), the secondary line 31, which is short-circuited at both ends, is not connected to the terminal circuit 80. Therefore, the directional coupler 10C can prevent adverse effects such as electrical leakage to the terminal circuit 80 caused by the connection between the terminal circuit 80 and the secondary line 31, which is short-circuited at both ends, and easily achieves the desired characteristics.

[0213] (4-2) Structure for outputting a detection signal from the coupling terminal Pcp that flows from end 312 to end 311 of the sub-line 31.

[0214] Figure 16 This is a state diagram showing the second connection structure of the directional coupler in the fourth embodiment.

[0215] like Figure 16 As shown, switches SW11 and SW14 of switch circuit 41C are short-circuited. Switches SW12 and SW13 of switch circuit 41C are disconnected. Therefore, end 311 of secondary line 31 is connected to the coupling terminal Pcp and not to the terminal circuit 80. End 312 of secondary line 31 is connected to switch SW43 of switch circuit 492 and not to the coupling terminal Pcp.

[0216] Switch SW43 of switching circuit 492 is short-circuited. As a result, end 312 of secondary line 31 is connected to terminal circuit 80 via switches SW14 and SW43.

[0217] According to this structure, the directional coupler 10C outputs a detection signal from the coupling terminal Pcp that is excited in the sub-line 31 and flows from the end 312 side to the end 311 side.

[0218] Switches SW23 and SW24 in the switching circuit 42C are short-circuited. According to this structure, ends 321 and 322 of the sub-line 32 are connected. That is, a circuit equivalent to the circuit in the first embodiment where switch SW92 is short-circuited (corresponding to (1-3) in the first embodiment) can be implemented.

[0219] Switch SW44 of switch circuit 492 is turned off. As a result, switches SW23 and SW24 of switch circuit 42C, and consequently sub-line 32, are not connected to terminal circuit 80.

[0220] Additionally, switches SW21 and SW22 of the switching circuit 42C are disconnected. Consequently, the secondary line 32 and the coupling terminal Pcp are not connected.

[0221] Furthermore, although the illustrations and detailed descriptions are omitted, the ends 321 and 322 of the sub-line 32 are also connected in the same way for the detection signal flowing from the end 311 side to the end 312 side of the sub-line 31 to be output from the coupling terminal Pcp (corresponding to the mode of (1-4) in the first embodiment).

[0222] Thus, the directional coupler 10C achieves a stable coupling degree above the desired value in a wide frequency band and can suppress the transmission loss of the main line 20.

[0223] Furthermore, in the manner described in (4-2), the secondary line 32, with its two ends short-circuited, is not connected to the terminal circuit 80. Therefore, the directional coupler 10C can prevent adverse effects such as electrical leakage to the terminal circuit 80 caused by the connection between the terminal circuit 80 and the secondary line 32 with its two ends short-circuited, easily achieving the desired characteristics. Additionally, in the manner described in (4-2), by not connecting the secondary line 32 with its two ends short-circuited to the coupling terminal Pcp, the impedance of the secondary line 31 outputting the detection signal and the coupling terminal Pcp can be matched with higher precision.

[0224] [Fifth Implementation]

[0225] The directional coupler of the fifth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 17 This is a structural diagram of the directional coupler according to the fifth embodiment.

[0226] The fifth embodiment of the directional coupler 10D, compared to the fourth embodiment of the directional coupler 10C, eliminates the switching circuit 492, which includes switches SW43 and SW44, equivalent to the "sixth switch" of the present invention, and differs in that each sub-line independently has a terminal circuit. The other structures of the directional coupler 10D are the same as those of the directional coupler 10C, and descriptions of the same locations are omitted.

[0227] like Figure 17 As shown, the directional coupler 10D includes a switching circuit 41D, a switching circuit 42D, a termination circuit 81, and a termination circuit 82. Switching circuit 41D has the same structure as switching circuit 41C. Switching circuit 42D has the same structure as switching circuit 42C.

[0228] The terminating circuit 81 is connected to the switching circuit 41D. More specifically, the terminating circuit 81 is connected to switches SW13 and SW14 of the switching circuit 41D. The terminating circuit 81 includes a variable resistor Rt1 and a variable capacitor Ct1. The parallel circuit of the variable resistor Rt1 and the variable capacitor Ct1 connects switches SW13 and SW14 to a reference potential. The terminating circuit 81 is configured to achieve impedance matching in the frequency band of the high-frequency signal detected by the sub-line 31.

[0229] The terminating circuit 82 is connected to the switching circuit 42D. More specifically, the terminating circuit 82 is connected to switches SW23 and SW24 of the switching circuit 42D. The terminating circuit 82 includes a variable resistor Rt2 and a variable capacitor Ct2. The parallel circuit of the variable resistor Rt2 and the variable capacitor Ct2 connects switches SW23 and SW24 to a reference potential. The terminating circuit 82 is configured to achieve impedance matching in the frequency band of the high-frequency signal detected by the sub-line 32.

[0230] (5-1) Structure for outputting a detection signal from the coupling terminal Pcp that flows from end 322 to end 321 of the sub-line 32.

[0231] Figure 18 This is a state diagram showing the first connection structure of the directional coupler in the fifth embodiment.

[0232] like Figure 18 As shown, switches SW21 and SW24 of switch circuit 42D are short-circuited. Switches SW22 and SW23 of switch circuit 42D are disconnected. Therefore, end 321 of secondary line 32 is connected to the coupling terminal Pcp and not to the terminal circuit 82. End 322 of secondary line 32 is connected to the terminal circuit 82 and not to the coupling terminal Pcp.

[0233] According to this structure, the directional coupler 10D outputs a detection signal from the coupling terminal Pcp that is excited in the sub-line 32 and flows from the end 322 side to the end 321 side.

[0234] Switches SW13 and SW14 in switch circuit 41D are short-circuited.

[0235] According to this structure, ends 311 and 312 of the sub-line 31 are connected. That is, a circuit equivalent to the circuit that short-circuits the switch SW91 in the first embodiment (corresponding to (1-1) in the first embodiment) can be realized.

[0236] Furthermore, although the illustrations and detailed descriptions are omitted, the ends 311 and 312 of the sub-line 31 are also connected in the same way for the detection signal flowing from the end 321 side to the end 322 side of the sub-line 32 to be output from the coupling terminal Pcp (corresponding to the (1-2) method of the first embodiment).

[0237] Thus, the directional coupler 10D achieves a stable coupling degree above the desired value in a wide frequency band and can suppress the transmission loss of the main line 20.

[0238] Furthermore, in the manner described in (5-1), the secondary line 31, with its two ends short-circuited, is not connected to the circuit on the secondary line 32 side. Therefore, the directional coupler 10D can prevent adverse effects caused by the connection between the circuit on the secondary line 32 side and the secondary line 31, with its two ends short-circuited, and easily achieve the desired characteristics.

[0239] Furthermore, by constructing a terminal circuit 82 that corresponds only to the sub-line 32, impedance matching for the detection signal in the sub-line 32 can be achieved with higher precision without increasing the circuit size.

[0240] (5-2) Structure for outputting a detection signal from the coupling terminal Pcp that flows from end 312 to end 311 of the sub-line 31.

[0241] Figure 19 This is a state diagram showing the second connection structure of the directional coupler in the fifth embodiment.

[0242] like Figure 19 As shown, switches SW11 and SW14 of switch circuit 41D are short-circuited. Switches SW12 and SW13 of switch circuit 41D are disconnected. Therefore, end 311 of secondary line 31 is connected to the coupling terminal Pcp and not to the terminal circuit 81. End 312 of secondary line 31 is connected to the terminal circuit 81 and not to the coupling terminal Pcp.

[0243] According to this structure, the directional coupler 10D outputs a detection signal from the coupling terminal Pcp that is excited in the sub-line 31 and flows from the end 312 side to the end 311 side.

[0244] Switches SW23 and SW24 in the switching circuit 42D are short-circuited. According to this structure, ends 321 and 322 of the sub-line 32 are connected. That is, a circuit equivalent to the circuit in the first embodiment where switch SW92 is short-circuited (corresponding to (1-3) in the first embodiment) can be implemented.

[0245] Additionally, switches SW21 and SW22 of the switching circuit 42D are disconnected. Consequently, the secondary line 32 and the coupling terminal Pcp are not connected.

[0246] Furthermore, although the illustrations and detailed descriptions are omitted, the ends 321 and 322 of the sub-line 32 are also connected in the same way for the detection signal flowing from the end 311 side to the end 312 side of the sub-line 31 to be output from the coupling terminal Pcp (corresponding to the mode of (1-4) in the first embodiment).

[0247] Thus, the directional coupler 10D achieves stable coupling near the desired value over a wide frequency band and can suppress transmission loss of the main line 20.

[0248] Furthermore, in the manner described in (5-2), the secondary line 32, with its two ends short-circuited, is not connected to the circuit on the secondary line 31 side. Therefore, the directional coupler 10D can prevent adverse effects caused by the connection between the circuit on the secondary line 31 side and the secondary line 32, with its two ends short-circuited, and easily achieve the desired characteristics.

[0249] Furthermore, by constructing a terminal circuit 81 that corresponds only to the secondary line 31, impedance matching for the detection signal in the secondary line 31 can be achieved with higher precision without increasing the circuit size.

[0250] Furthermore, the directional coupler 10D independently includes a termination circuit 81 for the secondary line 31 and a termination circuit 82 for the secondary line 32. This allows for independent setting of impedance matching relative to the frequency band detected in the secondary line 31 and the frequency band detected in the secondary line 32. Therefore, the directional coupler 10D can output a wider bandwidth detection signal with lower loss without increasing circuit size. Additionally, according to this structure, the directional coupler 10D can independently and with high precision suppress the adverse effects of the secondary lines 31 and 32 on the main line 20, further suppressing the degradation of the transmission characteristics of the main line 20.

[0251] [Sixth Implementation Method]

[0252] The directional coupler of the sixth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 20 This is a structural diagram of the directional coupler according to the sixth embodiment.

[0253] The directional coupler 10E of the sixth embodiment differs from the directional coupler 10A of the second embodiment in that each sub-line has an independently provided coupling terminal. The other structures of the directional coupler 10E are the same as those of the directional coupler 10A, and descriptions of identical locations are omitted.

[0254] like Figure 20 As shown, the directional coupler 10E includes a switch circuit 41E, a switch circuit 42E, a coupling terminal Pcp1, and a coupling terminal Pcp2. Switch circuit 41E has the same structure as switch circuit 41A. Switch circuit 42E has the same structure as switch circuit 42A. Furthermore, the directional coupler 10E does not include a switch equivalent to the "fifth switch" of the present invention.

[0255] The coupling terminal Pcp1 is connected to the switching circuit 41E. More specifically, the coupling terminal Pcp1 is connected to switches SW11 and W12.

[0256] The coupling terminal Pcp2 is connected to the switching circuit 42E. More specifically, the coupling terminal Pcp2 is connected to switches SW21 and W22.

[0257] (6-1) Structure for outputting a detection signal from the coupling terminal Pcp2 that flows from end 322 to end 321 of the secondary line 32.

[0258] Figure 21 This is a state diagram showing the first connection structure of the directional coupler according to the sixth embodiment.

[0259] like Figure 21 As shown, switches SW21 and SW24 of switch circuit 42E are short-circuited. Switches SW22 and SW23 of switch circuit 42E are disconnected. Therefore, end 321 of secondary line 32 is connected to coupling terminal Pcp2, but not to terminal circuit 80. End 322 of secondary line 32 is connected to terminal circuit 80, but not to coupling terminal Pcp2.

[0260] According to this structure, the directional coupler 10E outputs a detection signal from the coupling terminal Pcp2, which is excited in the sub-line 32 and flows from the end 322 side to the end 321 side.

[0261] Switches SW11 and SW12 in switch circuit 41E are short-circuited.

[0262] According to this structure, ends 311 and 312 of the sub-line 31 are connected. That is, a circuit equivalent to the circuit that short-circuits the switch SW91 in the first embodiment (corresponding to (1-1) in the first embodiment) can be realized.

[0263] Furthermore, although the illustrations and detailed descriptions are omitted, the ends 311 and 312 of the sub-line 31 are also connected in the same way for the detection signal flowing from the end 321 side to the end 322 side of the sub-line 32 to be output from the coupling terminal Pcp2 (corresponding to the (1-2) method of the first embodiment).

[0264] Thus, the directional coupler 10E achieves a stable coupling degree above the desired value in a wide frequency band and can suppress the transmission loss of the main line 20.

[0265] Furthermore, in the manner described in (6-1), the secondary line 31, with its two ends short-circuited, is not connected to the circuit on the secondary line 32 side. Therefore, the directional coupler 10E can prevent adverse effects caused by the connection between the circuit on the secondary line 32 side and the secondary line 31, with its two ends short-circuited, and easily achieve the desired characteristics.

[0266] (6-2) Structure for outputting a detection signal from the coupling terminal Pcp1 that flows from end 312 to end 311 of the sub-line 31.

[0267] Figure 22 This is a state diagram showing the second connection structure of the directional coupler in the sixth embodiment.

[0268] like Figure 22 As shown, switches SW11 and SW14 of switch circuit 41E are short-circuited. Switches SW12 and SW13 of switch circuit 41E are disconnected. Therefore, end 311 of secondary line 31 is connected to coupling terminal Pcp1, but not to terminal circuit 80. End 312 of secondary line 31 is connected to terminal circuit 80, but not to coupling terminal Pcp1.

[0269] According to this structure, the directional coupler 10E outputs a detection signal from the coupling terminal Pcp1 that is excited in the sub-line 31 and flows from the end 312 side to the end 311 side.

[0270] Switches SW21 and SW22 of the switching circuit 42E are short-circuited. According to this structure, ends 321 and 322 of the sub-line 32 are connected. That is, a circuit equivalent to the circuit in the first embodiment where switch SW92 is short-circuited (corresponding to (1-3) of the first embodiment) can be implemented.

[0271] Additionally, switches SW23 and SW24 in switch circuit 42E are disconnected. Therefore, sub-line 32 and terminal circuit 80 are not connected.

[0272] Furthermore, although the illustrations and detailed descriptions are omitted, the ends 321 and 322 of the sub-line 32 are also connected in the same way for the detection signal flowing from the end 311 side to the end 312 side of the sub-line 31 to be output from the coupling terminal Pcp1 (corresponding to the (1-4) method of the first embodiment).

[0273] Thus, the directional coupler 10E achieves a stable coupling degree above the desired value in a wide frequency band and can suppress the transmission loss of the main line 20.

[0274] Furthermore, in the manner described in (6-2), the secondary line 32, with its two ends short-circuited, is not connected to the circuit on the secondary line 31 side. Therefore, the directional coupler 10E can prevent adverse effects caused by the connection between the circuit on the secondary line 31 side and the secondary line 32, with its two ends short-circuited, and easily achieve the desired characteristics.

[0275] [Seventh Implementation Method]

[0276] The directional coupler of the seventh embodiment of the present invention will be described with reference to the accompanying drawings. Figure 23 This is a structural diagram of the directional coupler according to the seventh embodiment.

[0277] The directional coupler 10F of the seventh embodiment differs from the directional coupler 10D of the fifth embodiment in that each sub-line has an independently provided coupling terminal. Specifically, the directional coupler 10F has a structure that combines the structure of the terminal circuit side of the directional coupler 10D and the structure of the coupling terminal side of the directional coupler 10E. The other structures of the directional coupler 10F are the same as those of the directional couplers 10D and 10E, and descriptions of identical locations are omitted. Furthermore, like the directional coupler 10E of the sixth embodiment, the directional coupler 10F does not have a switch equivalent to the "fifth switch" of the present invention.

[0278] The directional coupler 10F includes switching circuits 41F and 42F, coupling terminals Pcp1 and Pcp2, termination circuit 81, and termination circuit 82. Switching circuit 41F has the same structure as switching circuits 41D and 41E. Switching circuit 42F has the same structure as switching circuits 42D and 42E.

[0279] The coupling terminal Pcp1 and the terminating circuit 81 are connected to the switching circuit 41F. More specifically, the coupling terminal Pcp1 is connected to switches SW11 and SW12 of the switching circuit 41F. The terminating circuit 81 is connected to switches SW13 and SW14 of the switching circuit 41F.

[0280] The coupling terminal Pcp2 and the terminating circuit 82 are connected to the switching circuit 42F. More specifically, the coupling terminal Pcp2 is connected to switches SW21 and SW22 of the switching circuit 42F. The terminating circuit 82 is connected to switches SW23 and SW24 of the switching circuit 42F.

[0281] Based on this structure, the directional coupler 10F achieves stable coupling near the desired value over a wide frequency band and is able to suppress transmission loss of the main line 20.

[0282] [Eighth Implementation Method]

[0283] The directional coupler of the eighth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 24 This is a structural diagram of the directional coupler according to the eighth embodiment.

[0284] The directional coupler 10G of the eighth embodiment differs from the directional coupler 10 of the first embodiment in that each sub-line independently has a coupling terminal and a termination circuit. The other structures of the directional coupler 10G are the same as those of the directional coupler 10, and descriptions of identical locations are omitted.

[0285] The directional coupler 10G has a coupling terminal Pcp1, a coupling terminal Pcp2, a termination circuit 81, and a termination circuit 82.

[0286] The coupling terminal Pcp1 and the terminating circuit 81 are connected to the switching circuit 41. More specifically, the coupling terminal Pcp1 is connected to switches SW11 and SW12 of the switching circuit 41. The terminating circuit 81 is connected to switches SW13 and SW14 of the switching circuit 41.

[0287] The coupling terminal Pcp2 and the terminating circuit 82 are connected to the switching circuit 42. More specifically, the coupling terminal Pcp2 is connected to switches SW21 and SW22 of the switching circuit 42. The terminating circuit 82 is connected to switches SW23 and SW24 of the switching circuit 42.

[0288] Based on this structure, the directional coupler 10G achieves stable coupling near the desired value over a wide frequency band and is able to suppress transmission loss of the main line 20.

[0289] [Ninth Implementation Method]

[0290] The directional coupler of the ninth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 25 This is a structural diagram of the directional coupler according to the ninth embodiment.

[0291] The directional coupler 10H of the ninth embodiment has a structure that combines the directional coupler 10B of the third embodiment and the directional coupler 10C of the fourth embodiment. More specifically, the directional coupler 10H includes a switching circuit 491 for the directional coupler 10B and a switching circuit 492 for the directional coupler 10C. The other structures of the directional coupler 10H are the same as those of the directional couplers 10B and 10C, and descriptions of the same positions are omitted.

[0292] The directional coupler 10F includes switching circuits 41H, 42H, 491, and 492. Switching circuit 41H has the same structure as switching circuits 41B and 41C. Switching circuit 42H has the same structure as switching circuits 42B and 42C.

[0293] Switching circuit 491 is connected between coupling terminal Pcp and switching circuit 41H, and between coupling terminal Pcp and switching circuit 42H. Switching circuit 492 is connected between terminating circuit 80 and switching circuit 41H, and between terminating circuit 80 and switching circuit 42H.

[0294] Based on this structure, the directional coupler 10F achieves stable coupling near the desired value over a wide frequency band and is able to suppress transmission loss of the main line 20.

[0295] [Tenth Implementation Method]

[0296] The directional coupler of the tenth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 26 This is a structural diagram of the directional coupler according to the tenth embodiment.

[0297] like Figure 26 As shown, the directional coupler 10I of the tenth embodiment differs from the directional coupler 10 of the first embodiment at the point where it has three sub-lines. The other structures of the directional coupler 10I are the same as those of the directional coupler 10, and descriptions of the same locations are omitted.

[0298] The directional coupler 10I includes a secondary line 33, a switching circuit 43, and a switch SW93.

[0299] The secondary line 33 is configured to electromagnetically couple with the primary line 20. For example, the secondary line 33 extends parallel to the primary line 20 at a predetermined interval. In this case, the shape of the secondary line 33 and its configuration relative to the primary line 20 are determined to achieve the desired coupling degree relative to the primary line 20 in the third frequency band.

[0300] The third frequency band is not entirely consistent with the first and second frequency bands. In other words, the third frequency band is different from the second and first frequency bands. The third frequency band may be a higher frequency band than the first and second frequency bands, such as a frequency band above 3.3 GHz.

[0301] Sub-line 33 has an end portion 331 at one end in the extending direction and an end portion 332 at the other end in the extending direction. Any two of sub-lines 31, 32, and 33 correspond to the "first sub-line" of the present invention, and the remaining one corresponds to the "second sub-line" of the present invention. Moreover, when sub-line 31 is the first sub-line, end portion 311 corresponds to the "first end" of the present invention, and end portion 312 corresponds to the "second end" of the present invention. When sub-line 32 is the first sub-line, end portion 321 corresponds to the "first end" of the present invention, and end portion 322 corresponds to the "second end" of the present invention. When sub-line 33 is the first sub-line, end portion 331 corresponds to the "first end" of the present invention, and end portion 332 corresponds to the "second end" of the present invention.

[0302] Switching circuit 43 includes switches SW31, SW32, SW33, and SW34. Switch SW31 is connected between end 331 of the secondary line 33 and coupling terminal Pcp, switching between short-circuiting and opening the connection between end 331 and coupling terminal Pcp. Switch SW32 is connected between end 332 of the secondary line 33 and coupling terminal Pcp, switching between short-circuiting and opening the connection between end 332 and coupling terminal Pcp. Switch SW33 is connected between end 331 of the secondary line 33 and terminal circuit 80, switching between short-circuiting and opening the connection between end 331 and terminal circuit 80. Switch SW34 is connected between end 332 of the secondary line 33 and terminal circuit 80, switching between short-circuiting and opening the connection between end 332 and terminal circuit 80. Switching circuit 43 is part of the "second switching circuit" of the present invention.

[0303] The coupling terminal Pcp side of switch SW31 is connected to the coupling terminal Pcp side of switch SW32. The terminal circuit 80 side of switch SW33 is connected to the terminal circuit 80 side of switch SW34. When the secondary line 33 is the "first secondary line", switches SW31, SW32, SW33 and SW34 correspond to the "first switch", "second switch", "third switch" and "fourth switch" of the present invention, respectively.

[0304] Switch SW93 is connected between ends 331 and 332 of the secondary line 33. Switch SW93 switches between short-circuiting and opening ends 331 and 332. When the secondary line 33 is the "first secondary line", switch SW93 corresponds to the "switching circuit" of the present invention.

[0305] Figure 27 This is a graph illustrating an example of the simulation results for the transmission characteristics (S21) of the main line. Figure 27In the diagram, solid lines represent the characteristics of the structure in this application, dashed lines represent the characteristics of comparison structure 1, and dotted lines represent the characteristics of comparison structure 2. Comparison structure 1 and comparison structure 2 represent the case where the sub-line without output detection signal is not short-circuited; comparison structure 1 represents the case with two sub-lines, and comparison structure 2 represents the case with three sub-lines.

[0306] like Figure 27 As shown, if the number of secondary lines increases, the attenuation frequency shifts to a lower level. For example, if... Figure 27 In the case of two secondary lines, the attenuation frequency is approximately 5.2 GHz, but with three secondary lines, the attenuation frequency drops to approximately 4.8 GHz. This means that it has a greater adverse effect on the frequency band of the high-frequency signal flowing through the main line 20 of the directional coupler 10I.

[0307] However, by incorporating the aforementioned structure, the directional coupler 10I can direct the attenuation electrode toward the high-frequency side (in... Figure 27 In the case of moving closer to the high-frequency side than 7.0 [GHz], the frequency is reduced.

[0308] Therefore, the main line 20 can suppress significant degradation of transmission characteristics over a wider frequency band, achieving low-loss transmission characteristics. Thus, the directional coupler 10I can suppress transmission loss of high-frequency signals flowing in the main line 20 over a wider frequency band and obtain a detection signal in the desired frequency band.

[0309] In particular, in the directional coupler 10I, by using three sub-lines, it is possible to detect a wider frequency band compared to using two sub-lines. Even in this case, the transmission loss of the high-frequency signal flowing in the main line 20 can be suppressed, and a detection signal of the desired frequency band can be obtained.

[0310] Furthermore, the case with three secondary lines is shown, but there can also be four or more secondary lines. In this case, one secondary line is used to detect the output signal, while the other secondary lines short-circuit at both ends.

[0311] [Eleventh Implementation Method]

[0312] The directional coupler of the eleventh embodiment of the present invention will be described with reference to the accompanying drawings. Figure 28 This is a structural diagram of the directional coupler according to the eleventh embodiment.

[0313] like Figure 28 As shown, the directional coupler 10J of the eleventh embodiment differs from the directional coupler 10 of the first embodiment in the point where the SP3T switch is used. The other structures of the directional coupler 10J are the same as those of the directional coupler 10, and descriptions of the same locations are omitted.

[0314] The directional coupler 10J includes a switching circuit 41J and a switching circuit 42J. The switching circuit 41J and the switching circuit 42J correspond to the "second switching circuit" of the present invention.

[0315] The switching circuit 41J includes switches SW113 and SW123. Switches SW113 and SW123 are SP3T (single-pole triple-throw) switching elements.

[0316] In switch SW113, the single-pole side terminal is connected to the coupling terminal Pcp. One terminal on the three-throw side is connected to end 311 of the secondary line 31, another terminal on the three-throw side is connected to end 312 of the secondary line 31, and the remaining terminal on the three-throw side is a floating terminal not connected anywhere. In switch SW123, the single-pole side terminal is connected to the terminal circuit 80. One terminal on the three-throw side is connected to end 311 of the secondary line 31, another terminal on the three-throw side is connected to end 312 of the secondary line 31, and the remaining terminal on the three-throw side is a floating terminal not connected anywhere.

[0317] The switching circuit 42J includes switches SW213 and SW223. Switches SW213 and SW223 are SP3T (single-pole triple-throw) switching elements.

[0318] In switch SW213, the single-pole side terminal is connected to the coupling terminal Pcp. One terminal on the three-throw side is connected to end 321 of the secondary line 32, another terminal on the three-throw side is connected to end 322 of the secondary line 32, and the remaining terminal on the three-throw side is a floating terminal not connected anywhere. In switch SW223, the single-pole side terminal is connected to the terminal circuit 80. One terminal on the three-throw side is connected to end 321 of the secondary line 32, another terminal on the three-throw side is connected to end 322 of the secondary line 32, and the remaining terminal on the three-throw side is a floating terminal not connected anywhere.

[0319] For example, when a detection signal flowing from end 322 to end 321 of the secondary line 32 is output from the coupling terminal Pcp, switch SW213 selects the terminal connected to end 321 of the secondary line 32 among the three-throw terminals, and switch SW223 selects the terminal connected to end 322 of the secondary line 32 among the three-throw terminals. Additionally, switch SW91 is short-circuited, and switch SW92 is open. Furthermore, switches SW113 and SW123 respectively select the floating terminal among the three-throw terminals.

[0320] According to this structure, the directional coupler 10J, like the directional coupler 10 of the first embodiment, can suppress the transmission loss of high-frequency signals flowing in the main line 20 over a wider frequency band and obtain a detection signal in the desired frequency band. Furthermore, in the event that a sub-line (e.g., sub-line 31) in sub-lines 31 and 32 that is not connected to the coupling terminal Pcp and the termination circuit 80 is short-circuited, the connection between sub-lines 31 and 32 can be avoided by selecting the floating terminal through the switching circuit 41J. Therefore, the adverse effects caused by the connection between sub-lines 31 and 32 can be reduced.

[0321] [Twelfth Implementation Method]

[0322] The directional coupler of the twelfth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 29 This is a structural diagram of the directional coupler according to the twelfth embodiment.

[0323] like Figure 29 As shown, the directional coupler 10K of the twelfth embodiment differs from the directional coupler 10H of the ninth embodiment in the point where the SPDT switch is used. The other structures of the directional coupler 10K are the same as those of the directional coupler 10H, and descriptions of the same locations are omitted.

[0324] The directional coupler 10K includes switching circuits 41K, 42K, 491K, and 492K.

[0325] The switching circuit 41K includes switches SW112 and SW122. Switches SW112 and SW122 are SPDT (single-pole double-throw) switching elements.

[0326] In switch SW112, the terminal on the single-pole side is connected to switch circuit 491K. One terminal on the double-throw side is connected to end 311 of secondary line 31, and the other terminal on the double-throw side is connected to end 312 of secondary line 31. In switch SW122, the terminal on the single-pole side is connected to switch circuit 492K. One terminal on the double-throw side is connected to end 311 of secondary line 31, and the other terminal on the double-throw side is connected to end 312 of secondary line 31.

[0327] The 42K switching circuit includes switches SW212 and SW222. Switches SW212 and SW222 are SPDT (single-pole double-throw) switching elements.

[0328] In switch SW212, the terminal on the single-pole side is connected to switch circuit 491K. One terminal on the double-throw side is connected to end 321 of secondary line 32, and the other terminal on the double-throw side is connected to end 322 of secondary line 32. In switch SW222, the terminal on the single-pole side is connected to switch circuit 492K. One terminal on the double-throw side is connected to end 321 of secondary line 32, and the other terminal on the double-throw side is connected to end 322 of secondary line 32.

[0329] Switching circuit 491K is an SPDT (single-pole double-throw) switching element. In switching circuit 491K, the terminal on the single-pole side is connected to the coupling terminal Pcp. One terminal on the double-throw side is connected to switch SW112 of switching circuit 491K, and the other terminal on the double-throw side is connected to switch SW212 of switching circuit 42K.

[0330] Switching circuit 492K is an SPDT (single-pole double-throw) switching element. In switching circuit 492K, the terminal on the single-pole side is connected to the terminal circuit 80. One terminal on the double-throw side is connected to switch SW122 of switching circuit 41K, and the other terminal on the double-throw side is connected to switch SW222 of switching circuit 42K.

[0331] According to this structure, the directional coupler 10K, like the directional coupler 10H of the ninth embodiment, is able to suppress the transmission loss of high-frequency signals flowing in the main line 20 over a wider frequency band and obtain a detection signal in the desired frequency band.

[0332] In addition, as shown in directional couplers 10J and 10K, the switching circuit is not limited to SPST (single-pole single-throw) switches, but can also be implemented using mPnT (m-pole n-throw: m and n are positive integers) switches.

[0333] [Thirteenth Implementation Method]

[0334] The directional coupler of the thirteenth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 30A , Figure 30B , Figure 30C This is a top view of the main circuit and the auxiliary circuit of the directional coupler according to the thirteenth embodiment. Figure 30A , Figure 30C Indicates the secondary line. Figure 30B Indicates the main line. Figure 31 This is a cross-sectional view schematically showing the structure of the directional coupler according to the thirteenth embodiment. Figure 31 express Figure 30A , Figure 30B , Figure 30C Section A-A.

[0335] The directional coupler 10L of the thirteenth embodiment implements a structural configuration of the directional coupler 10 of the first embodiment. The circuit structure of the directional coupler 10L is the same as that of the directional coupler 10, and the description of the circuit structure is omitted.

[0336] like Figure 30A , Figure 30B , Figure 30C , Figure 31 As shown, the directional coupler 10L includes a laminate 100. The laminate 100 is formed by stacking multiple insulating layers. For example, the laminate 100 is formed by stacking multiple prepreg layers on both sides of a core material layer.

[0337] like Figure 30B As shown, the main line 20 is a conductor extending in a prescribed shape. More specifically, the main line 20 is a generally continuous coil. Furthermore, the coil shape in this invention does not need to be a complete loop, but rather has at least a portion of a loop shape.

[0338] like Figure 31 As shown, the secondary line 31 is positioned on one side of the laminate 100 in the thickness direction relative to the primary line 20. Figure 30A As shown, the secondary line 31 is a conductor extending in a prescribed shape. More specifically, the secondary line 31 is approximately a two-turn coil. The secondary line 31 extends almost entirely along its direction of extension and runs parallel to the main line 20. Thus, the secondary line 31 can be electromagnetically coupled to the main line 20 with a prescribed coupling degree.

[0339] like Figure 31 As shown, the secondary line 32 is positioned on the opposite side of the thickness direction of the laminate 100 relative to the primary line 20. Figure 30C As shown, the secondary line 32 is a conductor extending in a prescribed shape. More specifically, the secondary line 32 is approximately a full-circuit coil. The secondary line 32 extends almost entirely along its direction of extension and runs parallel to the main line 20. Thus, the secondary line 32 can be electromagnetically coupled to the main line 20 with a prescribed coupling degree.

[0340] The length of the secondary line 31 is longer than the length of the secondary line 32. Therefore, the frequency band that can be coupled through the secondary line 31 is lower than the frequency band that can be coupled through the secondary line 32.

[0341] like Figure 30A As shown, ends 311 and 312 of the secondary line 31 are close to each other. Here, for example, as... Figure 30A As shown, "closer" means shorter than the shorter side (or diameter if the annulus is circular) that forms the central opening, wherein the central opening is the annular central opening formed by the sub-line 31, more preferably arranged at intervals of 1 / 2 or less, and further arranged at intervals of 1 / 4 or less.

[0342] With this structure, the connection distance between end 311 and switch SW91, as well as the connection distance between end 312 and switch SW91, can be shortened. Therefore, when switch SW91 is short-circuited, the inductance in the path containing switch SW91 can be reduced. Consequently, the reduction in resonant frequency shift caused by short-circuiting switch SW91 can be suppressed, and the effect of short-circuiting switch SW91 becomes more effective.

[0343] Similarly, as Figure 30C As shown, ends 321 and 322 of the secondary line 32 are close to each other. Here, for example, as... Figure 30C As shown, "closer" means shorter than the shorter side (or diameter if the annulus is circular) that forms the central opening, wherein the central opening is the annular central opening formed by the sub-line 32, more preferably arranged at intervals of 1 / 2 or less, and further arranged at intervals of 1 / 4 or less.

[0344] With this structure, the connection distances between end 321 and switch SW92, as well as between end 322 and switch SW92, can be shortened. Therefore, when switch SW92 is short-circuited, the inductance in the path containing switch SW92 can be reduced. Consequently, the reduction in resonant frequency shift caused by short-circuiting switch SW92 can be suppressed, and the effect of short-circuiting switch SW92 becomes more effective.

[0345] Furthermore, this embodiment is not limited to this one. The above description shows a configuration with both switch SW91 (a switch for short-circuiting the low-frequency side secondary line) and switch SW92 (a switch for short-circuiting the high-frequency side secondary line), but having either switch SW91 (a switch for short-circuiting the low-frequency side secondary line) or switch SW92 (a switch for short-circuiting the high-frequency side secondary line) is sufficient. In this case, the higher the frequency band, the more susceptible it is to the influence of the attenuation electrode. Therefore, the directional coupler only needs to have at least switch SW91 (a switch for short-circuiting the low-frequency side secondary line).

[0346] [Fourteenth Implementation]

[0347] The directional coupler of the fourteenth embodiment of the present invention will be described with reference to the accompanying drawings. Figure 32 This is a structural diagram of the directional coupler according to the fourteenth embodiment.

[0348] The directional coupler 10X of the fourteenth embodiment has a structure in which the switching circuits 41 and 42 of the directional coupler 10G of the eighth embodiment are omitted. The other structures of the directional coupler 10X are the same as those of the directional coupler 10G, and the descriptions of the same locations are omitted.

[0349] In this structure, the direction of the coupled signal obtained by the sub-line 31 and the sub-line 32 is one direction, but the directional coupler 10X is the same as the directional coupler 10G in the eighth embodiment. It can suppress the transmission loss of the high-frequency signal flowing in the main line 20 in a wider frequency band and obtain the detection signal of the desired frequency band.

[0350] Furthermore, the structures of the above-described embodiments can be appropriately combined to achieve the corresponding effects of each combination.

[0351] Explanation of reference numerals in the attached figures

[0352] 10, 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 10I, 10J, 10K, 10L, 10X… Directional couplers; 20… Main line; 31, 32, 33… Sub-line; 41, 42, 41A, 42A, 41B, 42B, 41C, 42C, 41D, 42D, 41E, 42E, 41F, 42F, 41H, 42H, 41J, 42J, 41K, 42K, 43, 491, 492, 491K, 492K… Switches Circuits; 80, 81, 82… terminal circuits; 100… stacked bodies; 311, 312, 321, 322, 331, 332… ends; P21, P22… input / output terminals; Pcp, Pcp1, Pcp2… coupling terminals; SW11-SW14, SW21-SW24, SW31-SW34, SW112, SW113, SW122, SW123, SW212, SW213, SW222, SW223, SW91, SW92, SW93… switches.

Claims

1. A directional coupler, comprising: Main line; The first and second auxiliary lines are configured to be electromagnetically coupled to the aforementioned main line. The first switching circuit is connected between the first and second terminals of the first sub-circuit to switch the short circuit and disconnection between the first and second terminals. The coupling terminal and the terminating circuit are connected to the first sub-line and the second sub-line mentioned above. as well as The second switching circuit is connected between the first auxiliary circuit and the second auxiliary circuit, the coupling terminal, and the terminal circuit. The second switching circuit selectively switches the connection between the coupling terminal and the terminal circuit to either the first auxiliary line or the second auxiliary line. When the second switching circuit connects the second auxiliary line to the coupling terminal and the terminal circuit, The aforementioned first switching circuit short-circuits the first terminal of the aforementioned first auxiliary circuit to the aforementioned second terminal.

2. The directional coupler according to claim 1, wherein, When the second switching circuit connects the first auxiliary line to the coupling terminal and the terminal circuit, The first switching circuit disconnects the first terminal of the first auxiliary circuit from the second terminal.

3. The directional coupler according to claim 1 or 2, wherein, The second switching circuit described above has: In the first connection method, the first end is connected to the coupling terminal, and the second end is connected to the terminal circuit; and In the second connection method, the second end is connected to the terminal circuit, and the first end is connected to the coupling terminal. The aforementioned second switching circuit switches between the aforementioned first connection method and the aforementioned second connection method.

4. The directional coupler according to claim 3, wherein, The second switching circuit described above has a third connection method, in which the first terminal and the second terminal are connected. The aforementioned second switching circuit switches between the aforementioned first connection method, the aforementioned second connection method, and the aforementioned third connection method. The short-circuit state of the first switching circuit is achieved through the third connection method.

5. The directional coupler according to claim 4, wherein, The second switching circuit described above includes: A first switch is connected between the first terminal and the coupling terminal. The second switch is connected between the second terminal and the coupling terminal. The third switch is connected between the first terminal and the terminal circuit. as well as The fourth switch is connected between the second terminal and the terminal circuit. The first switching circuit described above is composed of a combination of the first switch and the second switch, or a combination of the third switch and the fourth switch.

6. The directional coupler according to claim 5, wherein, The first switching circuit described above is composed of a combination of the first switch and the second switch described above.

7. The directional coupler according to claim 5 or claim 6, wherein, The second switching circuit described above includes a fifth switch, wherein the fifth switch switches between short circuits and open circuits between the first switch and the coupling terminal, and between the second switch and the coupling terminal.

8. The directional coupler according to claim 7, wherein, When the third connection method is achieved through the first switch and the second switch described above, The fifth switch disconnects the first switch from the coupling terminal and the second switch from the coupling terminal.

9. The directional coupler according to claim 7, wherein, When the first connection method is achieved through the first switch and the fourth switch described above, The fifth switch causes a short circuit between the first switch and the coupling terminal.

10. The directional coupler according to claim 8, wherein, When the first connection method is achieved through the first switch and the fourth switch described above, The fifth switch causes a short circuit between the first switch and the coupling terminal.

11. The directional coupler according to claim 5, wherein, The first switching circuit described above is composed of a combination of the third switch and the fourth switch described above.

12. The directional coupler according to claim 5 or claim 11, wherein, The second switching circuit described above includes a sixth switch, wherein the sixth switch switches between short circuits and disconnections between the third switch and the terminal circuit, and between the fourth switch and the terminal circuit.

13. The directional coupler according to claim 12, wherein, When the third connection method is achieved by using the third switch and the fourth switch mentioned above, The sixth switch disconnects the third switch from the coupling terminal and the fourth switch from the coupling terminal.

14. The directional coupler according to claim 12, wherein, When the second connection method is achieved through the aforementioned second switch and third switch, The sixth switch causes a short circuit between the third switch and the coupling terminal.

15. The directional coupler according to claim 13, wherein, When the second connection method is achieved through the aforementioned second switch and third switch, The sixth switch causes a short circuit between the third switch and the coupling terminal.

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