Wireless transmission system, control method, and program

Abstract

To reduce communication error by appropriately connecting a plurality of circuit boards.SOLUTION: A wireless transmission system 200 includes a coupler 201 including a plurality of circuit boards having a signal line and ground, and a coupler 202 for transmitting a signal to the coupler 201, a first circuit board 207 is connected to a second circuit board 208 with conductors 218, 219 having a width approximately equivalent to signal lines 210, 211 or less.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a wireless transmission system. [Background technology]

[0002] In recent years, wireless transmission systems that communicate wirelessly by electromagnetic and / or magnetic field coupling using closely spaced couplers have been developed. In these systems, baseband signals can be transmitted without modulation, making the circuit configuration simple and enabling high-speed, low-latency communication.

[0003] A wireless transmission system using electromagnetic and / or magnetic field coupling will be described with reference to FIG. 1. FIG. 1(a) is a system configuration diagram, and FIG. 1(b) is a diagram showing the waveform of a signal in the wireless transmission system. As shown in FIG. 1(a), the wireless transmission system 100 is composed of a transmitter (transmission coupler) 101 and a receiver (reception coupler) 102. The transmitter 101 includes a transmission circuit 103 and a transmission coupler 104, and the receiver 102 includes a reception circuit 105 and a reception coupler 106. The transmitter 101 transmits a digital signal generated by the transmission circuit 103 from the transmission coupler 104 without modulation. The receiver 102 receives the signal transmitted from the transmission coupler 104 as a differential signal using the reception coupler 106. The receiver 102 restores the received signal based on the threshold of a comparator included in the reception circuit 105. A signal 107 shown in FIG. 1(b) is a digital signal generated by the transmission circuit 103. Moreover, signal 108 is the differentiated signal received by receiving coupler 106. Threshold value 109 indicated by a dotted line is the threshold value of a comparator included in receiving circuit 105. Signal 110 is the signal restored by receiving circuit 105.

[0004] In the wireless transmission system described above, one coupler is long (hereinafter, long coupler) and the other coupler is short (hereinafter, short coupler), and wireless communication in a moving body is possible by moving the short coupler in the long side direction of the long coupler. When a long coupler is configured using a substrate, the length of the long coupler is limited to a certain size (work size of the substrate) due to manufacturing reasons. Therefore, as shown in Patent Document 1, a long coupler that is equal to or larger than the work size of the substrate can be configured by connecting multiple substrates with solder or conductive paste. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-149641 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, if multiple boards are connected without considering the line width, line thickness, and line spacing of the signal lines and ground lines of the boards, impedance mismatch occurs. In this case, ringing occurs at the connection point between the boards, and the signal waveform becomes distorted, which may cause erroneous data to be restored and communication errors to occur.

[0007] In view of the above problems, an object of the present invention is to reduce the occurrence of communication errors by appropriately connecting multiple boards. [Means for solving the problem]

[0008] In order to achieve the above object, the wireless transmission system of the present invention comprises: Each of the first couplers Substrate teeth, A signal line and a ground are included, The first coupler First Substrate and the second substrate Signal line The first conductor Via Connected The ground of the first board and the ground of the second board are connected via a second conductor, and the width of the signal line of the first board, the width of the signal line of the second board, and the width of the first conductor are approximately equal. It is characterized by:

[0009] In addition, a wireless transmission system according to another aspect of the present invention includes a first coupler including a plurality of substrates; a second coupler that transmits a signal by electric and / or magnetic field coupling with the first coupler; Each of the plurality of substrates has a signal line and a ground, The first substrate to be Signal line a second substrate included in the plurality of substrates via a connector Signal line and a plurality of pins of the connector are connected to each of the signal lines of the first board and the signal lines of the second board.

[0010] In addition, a wireless transmission system according to another aspect of the present invention includes a first coupler including a plurality of substrates; a second coupler that transmits a signal by electric and / or magnetic field coupling with the first coupler; The first and second substrates included in the plurality of substrates each have a signal line and a ground line. a third substrate included in the plurality of substrates has a spring contact, and the first substrate Signal line and the second substrate Signal line are connected via the spring contacts of the third substrate which are connected to the respective signal lines.

[0011] Moreover, a wireless transmission system according to another aspect of the present invention comprises a first coupler including a plurality of substrates, and a second coupler that transmits a signal with the first coupler by electric field and / or magnetic field coupling, each of the plurality of substrates having a signal line and a ground, and a first via that connects to the signal line of a first substrate included in the plurality of substrates and a second via that connects to the signal line of a second substrate included in the plurality of substrates are connected via a conductor. Effect of the Invention

[0012] According to the present invention, by appropriately connecting a plurality of boards, the occurrence of communication errors can be reduced. [Brief description of the drawings]

[0013] [Figure 1] 1 is a diagram showing a system configuration and signal waveforms of a wireless transmission system 100 according to a conventional technique. [Diagram 2] 1 is a diagram showing a system configuration of a wireless transmission system 200 according to a first embodiment. [Diagram 3] 5 is a diagram showing a simulation result of the impedance of the wireless transmission system 200 according to the first embodiment. FIG. [Figure 4] FIG. 11 is a diagram showing a configuration of a transmitter 201 according to a second embodiment. [Diagram 5] FIG. 11 is a diagram showing a configuration of a connection unit 401 according to a second embodiment. [Figure 6] FIG. 11 is a diagram illustrating a simulation result of the impedance of the wireless transmission system 200 according to the second embodiment. [Figure 7] FIG. 11 is a diagram showing a configuration of a transmitter 201 according to a third embodiment. [Figure 8] FIG. 11 is a diagram showing a configuration of a connection unit 701 according to a third embodiment. [Figure 9] FIG. 11 is a diagram showing a configuration of a transmitter 201 according to a fourth embodiment. [Figure 10] FIG. 10 is a diagram showing a configuration of a connection unit 1001 according to a fourth embodiment. [Figure 11] FIG. 13 is a diagram showing another configuration of the transmitter 201 according to the fourth embodiment. [Figure 12] FIG. 12 is a diagram showing a configuration of a connection unit 1201 according to a fourth embodiment. [Figure 13] FIG. 13 is a diagram showing another configuration of the transmitter 201 according to the fourth embodiment. [Figure 14] FIG. 14 is a diagram showing a configuration of a connection unit 1401 according to a fourth embodiment. [Figure 15] FIG. 17 is a diagram showing the structure of a resin member 1701 according to the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] [Embodiment 1] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Note that the configurations shown in the following embodiments are merely examples, and the present invention is not limited to the illustrated configurations.

[0015] <Embodiment 1> Fig. 2 is a diagram showing a system configuration of a wireless transmission system 200 according to the first embodiment. Fig. 2(a) shows a system configuration diagram of the wireless transmission system 200 according to the present embodiment on the XZ plane. Note that Fig. 2(a) shows only the configuration necessary for explaining the present embodiment, and the wireless transmission system 200 may have functions and configurations not shown in this figure.

[0016] The wireless transmission system 200 includes a transmitter 201 and a receiver 202. The transmitter 201 includes a transmission circuit 203 and a coupler (transmission coupler) 204 for transmission. The receiver 202 includes a reception circuit 205 and a coupler (reception coupler) 206 for reception. In the wireless transmission system 200, a digital signal generated by the transmission circuit 203 is transmitted via the transmission coupler 204, the digital signal is received by the reception coupler 206, and the signal waveform is shaped by the reception circuit 205, thereby performing wireless communication. The transmission coupler and the reception coupler perform wireless communication by electric field and / or magnetic field coupling.

[0017] The transmission coupler 204 includes a first transmission coupler 207, a second transmission coupler 208, and a connection unit 209 that connects the first and second transmission couplers. Note that, although the transmission coupler 204 is configured with two transmission couplers in this embodiment, the present invention is not limited to this, and may be configured with three or more transmission couplers.

[0018] 2(b) shows a configuration of the transmitter 201 according to the first embodiment when viewed on the XY plane. The first transmission coupler 207 of the transmission coupler 204 includes a first signal line 210, a second signal line 211, and a first ground conductor 212. The second transmission coupler 208 includes a third signal line 213, a fourth signal line 214, a second ground conductor 215, a first termination resistor 216, and a second termination resistor 217. The connection unit 209 connecting the first transmission coupler 207 and the second transmission coupler 208 includes a fifth signal line 218, a sixth signal line 219, and a third ground conductor 220.

[0019] In the transmitter 201 according to the first embodiment, the signal lines are not arranged on the same plane as the ground conductors, but the plane on which the signal lines are arranged and the plane on which the ground conductors are arranged are arranged to face each other in the z-axis direction. The plane on which the ground conductors are arranged is closer to the receiving coupler 206 than the plane on which the signal lines are arranged.

[0020] The first signal line 210 and the third signal line 213 are electrically connected by soldering through a fifth signal line 218. The second signal line 211 and the fourth signal line 214 are electrically connected by soldering through a sixth signal line 219. The first ground conductor 212 and the second ground conductor 215 are electrically connected by soldering through a third ground conductor 218. One end of the first termination resistor 216 is connected to an end of the third signal line 213, and one end of the second termination resistor 217 is connected to an end of the fourth signal line 214. The other ends of both the first and second termination resistors are connected to the second ground conductor 215.

[0021] 3 is a graph showing a simulation result of the impedance of the wireless transmission system 200 according to the first embodiment. Specifically, the graph shows a result of a TDR (time domain reflectometry) simulation of the first transmitting coupler 207, the second transmitting coupler 208, and the connection unit 209. The vertical axis represents impedance, and the horizontal axis represents time.

[0022] The impedance of the first transmitting coupler 207 is about 95Ω (in the range of 2.2 to 2.35nS), and the impedance of the second transmitting coupler 208 is about 95Ω (2.6 to 2.7nS). The signal line width in the Y-axis direction of the first, second, third, and fourth signal lines of the first transmitting coupler 107 and the second transmitting coupler 208 is 5mm. The impedance of the connection part 209 is shown in the range of 2.35 to 2.6nS.

[0023] The impedances when the widths in the Y-axis direction of the fifth and sixth signal lines of the connection part 209 are set to 1, 3, 5, 7, and 9 mm are shown in 301, 302, 303, 304, and 305 in FIG. 3, respectively. As can be seen from graph 303 in FIG. 3, when the line width of the signal line of the connection part 209 is 5 mm, the impedance is almost the same as that of the first and second transmission couplers. Also, as can be seen from graph 302, when the line width of the signal line of the connection part 209 is 3 mm, the impedance is 97.8 Ω. Also, as can be seen from graph 304, when the line width of the signal line of the connection part 209 is 7 mm, the impedance is 91.8 Ω. When the line width is 3 mm and 7 mm, the impedance of the connection part 209 is within ±5% of the impedance of the first and second transmission couplers, which is 95 Ω, so that the impedance is matched at the connection part 209. In this case, since impedance matching is achieved between each transmitting coupler and connection section 209, the occurrence of ringing at connection section 209 is suppressed, and the occurrence of communication errors is suppressed.

[0024] On the other hand, as can be seen from graph 301, when the line width of the signal line of connection portion 209 is 1 mm, the impedance is 103 Ω. Also, as can be seen from graph 305, when the line width of the signal line of connection portion 209 is 9 mm, the impedance is 86 Ω. In these cases, although slight, impedance mismatch occurs at connection portion 209. Therefore, ringing occurs at connection portion 209, which may cause a communication error.

[0025] As described above, in this embodiment, by making the line width of the signal line of the connection portion 209 approximately equal to the line width of the signal line of the transmitting coupler (within ±40%), it is found that impedance mismatch can be suppressed and the occurrence of communication errors can be suppressed even if the coupler is made longer.

[0026] In addition, the connection part 209 in this embodiment may be configured with a flexible board, may be configured with an FR4 (Flame Retardant Type 4) board, may be configured with a Teflon (registered trademark) board, or may be configured with a ceramic board. Alternatively, the connection part 209 may be a conductor that is not configured on a board.

[0027] <Embodiment 2> In the wireless transmission system 200 according to the first embodiment, the signal lines and the ground conductors are arranged on different planes. In the second embodiment, a wireless transmission system 200 is disclosed in which the signal lines of the connection section 209 are arranged on the same plane as the ground conductor. In this embodiment, only the differences from the first embodiment will be described.

[0028] The configuration of the wireless transmission system 200 according to this embodiment is almost the same as that shown in Fig. 2(a). However, the configuration of the connection unit 401 that connects the first transmission coupler 207 and the second transmission coupler 208 is different from that of the first embodiment.

[0029] FIG. 4 shows the configuration of the transmitter 201 according to this embodiment. FIG. 5 shows the detailed configuration of the connection unit 401 according to this embodiment. As shown in FIG. 4, the first transmission coupler 207 and the second transmission coupler 208 are connected via the connection unit 401. The connection unit 401 includes a seventh signal line 402, an eighth signal line 403, a fourth ground conductor 404, a fifth ground conductor 405, and a sixth ground conductor 406. An end of the first transmission coupler 210 is connected via a via 407 to a via pad 408 that is disposed on the same plane as the ground conductors of the connection unit 401. In this case, one end of the first signal line 210 of the first transmission coupler 207 is connected to the seventh signal line 402 via the via 407 and the via pad 408. Similarly, the third signal line 213 of the second transmitting coupler 208 is also connected to the seventh signal line 402 through a via and a via pad. That is, the first transmitting coupler 207 and the second transmitting coupler 208 are connected to each other through the seventh signal line 402. Similarly, the second signal line 211 of the first transmitting coupler 207 and the fourth signal line 214 of the second transmitting coupler 208 are connected to each other through an eighth signal line 403.

[0030] 4 and 5, it is not necessary to place the connection unit 401 on a surface adjacent to the receiving coupler 206, so it is possible to place the receiving coupler and the transmitting coupler closer to each other than in embodiment 1. In this case, the received signal strength is increased compared to the system of embodiment 1, enabling faster communication.

[0031] 6 shows a simulation result of the impedance of the wireless transmission system 200 according to the second embodiment. Specifically, it is a graph showing a result of a TDR (time domain reflectometry) simulation of the first transmitting coupler 207, the second transmitting coupler 208, and the connection unit 401. The vertical axis represents impedance, and the horizontal axis represents time.

[0032] The impedance of the first transmitting coupler 207 is about 95Ω (in the range of 2.2 to 2.35 nS), and the impedance of the second transmitting coupler 208 is about 95Ω (2.6 to 2.7 nS). The signal line width in the Y-axis direction of the first, second, third, and fourth signal lines of the first transmitting coupler 107 and the second transmitting coupler 208 is 5 mm. The impedance of the connection part 401 is shown in the range of 2.35 to 2.6 nS.

[0033] The impedances when the widths in the Y-axis direction of the seventh signal line 402 and the eighth signal line 403 of the connection portion 401 are set to 0.5 mm, 2.5 mm, 5 mm, and 8 mm are shown in 601, 602, 603, and 604, respectively. The simulation was performed while the distances between the seventh signal line 402 and the fourth ground conductor 404 and the fifth ground conductor 405 were kept constant at 0.3 mm. The simulation was also performed while the distances between the eighth signal line 403 and the fourth ground conductor 404 and the sixth ground conductor 406 were kept constant at 0.3 mm.

[0034] As can be seen from graphs 602 and 603, when the line width of each signal line of connection part 401 is 2.5 mm and 5 mm, the impedance of connection part 401 is 98.5 Ω and 92 Ω, which is almost equal to the impedance of the transmitting coupler. In these cases, the impedance of connection part 201 is within ±5% of the impedance of the transmitting coupler, 95 Ω. Therefore, when the line width of each signal line of connection part 401 is 2.5 mm and 5 mm, impedance matching is achieved at connection part 401.

[0035] On the other hand, as can be seen from graph 601, when the line width of each signal line of connection portion 401 is 0.5 mm, the impedance of connection portion 401 is 111.5 Ω. Also, as can be seen from graph 604, when the line width of each signal line of connection portion 401 is 8 mm, the impedance of connection portion 401 is 89 Ω. In either case, the impedance of connection portion 401 exceeds ±5% of the impedance of the transmitting coupler, 95 Ω, and a slight impedance mismatch occurs. Therefore, ringing occurs in connection portion 401, which may cause a communication error.

[0036] As described above, in the second embodiment, the signal lines of the connection unit 401 are arranged on the same plane as the ground conductor, so that impedance matching can be achieved even if the line width of the signal lines of the connection unit 401 is narrower than that of the first embodiment. Specifically, in the second embodiment, the line width of the signal lines of the connection unit 401 can be up to half (50%) of the line width of the signal lines of the transmitting coupler.

[0037] In the first coupler 207 and the second coupler 208, the characteristic impedance is determined by the electromagnetic field created by the first ground conductor 212 and the second ground conductor 215, which are arranged on a different plane from the signal lines. However, in the connection unit 401, the ground conductors are arranged on the same plane as the signal lines, not on a different plane, so that when the line width of the signal lines is the same, the characteristic impedance of the connection unit is lower than that of the transmitting coupler. Therefore, the line width of the signal lines of the connection unit can be made thinner in the second embodiment, in which the signal lines and the ground conductors of the connection unit are arranged on the same plane, than in the first embodiment, in which the signal lines and the ground conductors of the connection unit are arranged on different planes.

[0038] In addition, the connection part 401 in this embodiment may be configured with a flexible board, may be configured with an FR4 (Flame Retardant Type 4) board, may be configured with a Teflon board, may be configured with a ceramic board, or may be a conductor that is not configured on a board.

[0039] <Embodiment 3> In the first and second embodiments, the signal lines of the transmitting couplers are connected so as to match the impedance by soldering the connecting parts which are conductors. In the third embodiment, a wireless communication system 200 is disclosed in which the transmitting couplers are connected using connectors. Note that in this embodiment, only the points different from the first and second embodiments will be described.

[0040] The configuration of the wireless transmission system 200 according to this embodiment is almost the same as that shown in Fig. 2(a). However, the configuration of the connection unit 701 that connects the first transmission coupler 207 and the second transmission coupler 208 is different from that of the first and second embodiments.

[0041] FIG. 7 shows the configuration of the transmitter 201 according to this embodiment. FIG. 8 shows the detailed configuration of the connection unit 701 according to this embodiment. FIG. 8 is a diagram of the connection unit 701 when viewed from the back side with respect to the viewpoint of FIG. 7. As shown in FIG. 7, the first transmission coupler 207 and the second transmission coupler 208 are connected via the connection unit 701. The connection unit 701 includes connectors 702 and 703 having a plurality of pins. The connectors 702 and 703 are in a male-female relationship, and are electrically connected and mechanically mated. In this embodiment, the case where the number of pins of the connectors 702 and 703 is seven is shown, but the number of pins is not limited to this.

[0042] The pins of the connector 702 connect to the conductor patterns 704 and 705, and the first ground conductor 212. The conductor pattern 704 connects to the second signal line 211 of the first transmitting coupler 207 through a conductor via 708. The conductor pattern 705 connects to the first signal line 210 of the first transmitting coupler 207 through a conductor via 709.

[0043] The pins of the connector 703 connect to the conductor patterns 706, 707, and the second ground conductor 215. The conductor pattern 706 connects to the fourth signal line 214 of the second transmitting coupler 208 through a conductor via 710. The conductor pattern 707 connects to the third signal line 213 of the second transmitting coupler 208 through a conductor via 711.

[0044] Table 1 shows the measurement results of the impedance of the wireless transmission system 200 according to the embodiment 3. Specifically, the measurement results are shown in TDR (time domain reflectometry) of the first transmitting coupler 207, the second transmitting coupler 208, and the connection unit 701.

[0045] [Table 1]

[0046] Condition 1 is a measurement result in a state where only one pin of connectors 702, 703 is connected to each of conductor patterns 704, 705, 706, and 707. Condition 2 is a measurement result in a state where multiple (two or more) pins of connectors 702, 703 are connected to each of conductor patterns 704, 705, 706, and 707.

[0047] From the results shown in Table 9, the impedance difference between the connection part 701 and each transmitting coupler is smaller and better matched when multiple pins are connected to the conductor pattern than when a single pin is connected. This is because the signal line width is generally much larger than the connector pin width. Therefore, by using multiple connector pins, the signal line width and the sum of the pin widths become roughly equivalent, and impedance matching is achieved.

[0048] As described above, in the third embodiment, when multiple transmission couplers are coupled using a connector, impedance matching is achieved by connecting multiple pins of the connector to the signal lines of each transmission coupler. By matching the impedance, the occurrence of communication errors is suppressed.

[0049] In this embodiment, the connectors 702 and 703 are connectors having seven pins, but this is not limited to this. The connectors only need to have twice the number of pins as the signal lines to be connected and one pin for connecting to a ground conductor. For the wireless transmission system 200 of this embodiment, a connector having at least five pins is sufficient.

[0050] <Embodiment 4> In the third embodiment, the wireless transmission system 200 in which the transmission couplers are connected to each other via a connector is configured so that multiple pins of the connector are connected to the communication line of the transmission coupler, thereby matching the impedance. Assuming that the transmission coupler is fixed to the housing of the product, in the configuration of the third embodiment, the transmission couplers are first connected to each other using a connector, and then the transmission coupler is fixed to the housing using a screw, double-sided tape, or the like. However, when the transmission coupler is fixed to the housing in this procedure, there is a risk that the connection part will come off. In the fourth embodiment, a wireless transmission system 200 is disclosed in which a coaxial cable, a spring contact, a jumper pin, or the like is used as a connection part so that the fixed transmission couplers can be connected to each other after the transmission couplers are fixed to the housing. Note that in this embodiment, only the points different from the first to third embodiments will be described.

[0051] The configuration of a wireless transmission system 200 according to this embodiment is almost the same as that shown in Fig. 2(a). However, the configuration of the connection section that connects the first transmission coupler 207 and the second transmission coupler 208 is different from that of the first to third embodiments.

[0052] Fig. 9 shows the configuration of transmitter 201 using a coaxial connector for connection unit 1001. Fig. 10 shows the detailed configuration of connection unit 1001. Fig. 10 is a diagram of connection unit 1001 as viewed from the back side with respect to the viewpoint of Fig. 9. Note that, among the configuration of connection unit 1001 shown in Fig. 10, the same configuration as connection unit 701 shown in Fig. 8 is denoted by the same reference numerals as in Fig. 8. As shown in Fig. 9, first transmission coupler 207 and second transmission coupler 208 are connected by connection unit 1001 using coaxial cables 1006 and 1007.

[0053] The connection unit 1001 includes coaxial connectors 1002, 1003, 1004, and 1005, and coaxial cables 1006 and 1007. The core of the coaxial connector 1002 is connected to the conductor pattern 704, and the ground of the coaxial connector 1002 is connected to the first ground conductor 212. The core of the coaxial connector 1003 is connected to the conductor pattern 705, and the ground of the coaxial connector 1003 is connected to the first ground conductor 212. The core of the coaxial connector 1004 is connected to the conductor pattern 706, and the ground of the coaxial connector 1004 is connected to the second ground conductor 215. The core of the coaxial connector 1005 is connected to the conductor pattern 707, and the ground of the coaxial connector 1005 is connected to the second ground conductor 216.

[0054] Coaxial connectors 1002 and 1004 are connected by a coaxial cable 1006, and coaxial connectors 1003 and 1005 are connected by a coaxial cable 1007. Both coaxial connectors and coaxial cables are manufactured with an impedance of 50Ω, and the differential impedance is 100Ω. Therefore, impedance mismatch does not basically occur at connection portion 1001. By configuring connection portion 1001 as shown in FIG. 11, wireless transmission system 200 can suppress the occurrence of communication errors.

[0055] Incidentally, instead of the coaxial cables, receptacles that mate with the coaxial connectors 1002 to 1005 may be arranged on a substrate, and the receptacles may be connected to each other by a wiring pattern on the substrate.

[0056] Fig. 11 shows the configuration of transmitter 201 using spring contacts in connection section 1201. Fig. 12 shows the detailed configuration of connection section 1201. As shown in Fig. 11, first transmitting coupler 207 and second transmitting coupler 208 are connected via connection section 1201. The spring contacts are formed on substrate 1210. Spring contact connectors 1202, 1203, 1204, 1205, 1206, 1207, 1208, and 1209 are mounted on substrate 1210.

[0057] In the substrate 1210, the spring contact connectors 1202 and 1206 are electrically connected. Similarly, the spring contact connectors 1203 and 1207, 1204 and 1208, and 1205 and 1209 are electrically connected to each other. The spring contact connector 1203 is in contact with the conductor pattern 705. Similarly, the spring contact connector 1204 is in contact with the conductor pattern 704. Furthermore, the spring contact connectors 1207 and 1208 are in contact with the conductor patterns 707 and 706, respectively. As a result, the first transmitting coupler 207 and the second transmitting coupler 208 are connected to each other via the spring contacts.

[0058] The spring contact connectors 1202 , 1205 are in contact with the first conductor ground 212 of the first transmit coupler 207 , and the spring contact connectors 1206 , 1209 are in contact with the second conductor ground 215 of the second transmit coupler 208 .

[0059] Spring contact connectors 1203 and 1207, and 1204 and 1208 form a line through which a signal flows on connection portion 1210. Furthermore, spring contact connectors 1202, 1205, 1206, and 1209 that connect to ground conductors near the line become the ground of the path through which the signal flows, and the above eight spring contact connectors can form a differential transmission line. By setting the impedance of these spring contacts to a differential of 100 Ω, it is possible to suppress the occurrence of mismatch between transmitting couplers.

[0060] Instead of the spring contacts, multiple metals may be mounted on the substrate 1210, and each of the mounted metals may be brought into contact with each of the conductor patterns of each transmitting coupler. The shape of the metal may be, but is not limited to, a rectangular parallelepiped, a cylindrical column, or a polygonal prism. Alternatively, multiple conductor patterns may be formed on the substrate 1210, and each of the mounted conductor patterns may be brought into contact with each of the conductor patterns of each transmitting coupler.

[0061] Fig. 13 shows the configuration of transmitter 201 using a jumper pin at connection section 1401. Fig. 14 shows the detailed configuration of connection section 1401. Fig. 14 is a diagram of connection section 1401 as viewed from below with respect to the viewpoint of Fig. 13. As shown in Fig. 13, first transmission coupler 207 and second transmission coupler 208 are connected via connection section 1401.

[0062] Connection section 1401 includes pin plugs 1402, 1403, 1404, 1405, 1406, 1407, 1408, and 1409, and vias 1410, 1411, 1412, 1413, 1414, 1415, 1416, and 1417. Connection section 1401 further includes jumper pins 1418, 1419, 1420, and 1421. The pin plugs and the vias surrounding them are electrically connected with solder.

[0063] The vias 1411 and 1412 are connected to the second signal line 211 and the first signal line 210 of the first transmitting coupler 207, respectively. The vias 1415 and 1416 are connected to the fourth signal line 214 and the third signal line 213 of the second transmitting coupler 208, respectively. The vias 1410 and 1413 are connected to the first ground conductor 212 of the first transmitting coupler 207, and the vias 1414 and 1417 are connected to the second ground conductor 215 of the second transmitting coupler 208.

[0064] Jumper pin 1418 connects pin plugs 1402 and 1406. Jumper pin 1419 connects pin plugs 1403 and 1407. Jumper pin 1420 connects pin plugs 1404 and 1408. Jumper pin 1421 connects pin plugs 1405 and 1409.

[0065] Table 2 shows the results of a simulation of the impedance of the wireless transmission system 200 having the connection unit 1401 shown in Figures 13 and 14. Specifically, the results of a TDR (time domain reflectometry) simulation of the first transmitting coupler 207, the second transmitting coupler 208, and the connection unit 1401 are shown.

[0066] [Table 2]

[0067] Condition 3 shows the simulation results of the impedance when the first ground conductor 212 does not cover the area 1430 in Fig. 14 and the second ground conductor 215 does not cover the area 1431. In this case, the impedance of the connection portion 1401 is 88 to 133 Ω, and there is a slight mismatch with the impedance of each transmitting coupler.

[0068] Condition 4 shows the results of a simulation of the impedance when the first ground conductor 212 is extended to cover the area 1430, and the second ground conductor 215 is extended to cover the area 1431. In this case, the impedance of the connection portion 1401 is 88 to 113 Ω, which shows that the mismatch with the impedance of the transmitting coupler is reduced.

[0069] Condition 5 shows the simulation results of impedance when resin member 1701 shown in Fig. 15 is arranged at connecting portion 1401. Resin member 1701 is arranged so that jumper pins 1418, 1419, 1420, and 1421 fit into holes 1702, 1703, 1704, and 1705, respectively. In this case, the impedance of connecting portion 1401 is 85 to 122 Ω, and it is clear that the mismatch with the impedance of the transmitting coupler is reduced compared to the case of condition 3.

[0070] As shown in Table 2, when using a jumper pin at the connection, it is possible to reduce impedance mismatch by extending the ground conductor portion or by placing an additional resin component.

[0071] As described above in the fourth embodiment, the connecting portion between the transmitting couplers can be made of a coaxial cable, a spring contact, a jumper pin, etc. In this case, depending on the material used for the connecting portion, the impedance mismatch can be reduced by improving the configuration, such as by widening the area of ​​the ground conductor or by using other materials.

[0072] In the first to fourth embodiments, the first transmitting coupler 207 and the second transmitting coupler 208 are couplers that perform transmission, and the receiving coupler 206 is a coupler that performs reception, but the roles of transmission and reception may be interchanged. In this case, the transmitting circuit and the receiving circuit connected to each coupler are also interchanged.

[0073] In addition, in the first to fourth embodiments, the first transmission coupler 207 and the second transmission coupler 208 have differential signal lines, but the present invention is not limited to this and each transmission coupler may be configured with a single signal line.

[0074] In the first to fourth embodiments, the wireless transmission system 200 has two transmission couplers, but is not limited to this and may have three or more transmission couplers. In this case, the wireless transmission system 200 has a number of connection parts that increases in proportion to the increase in the number of transmission couplers.

[0075] Moreover, the transmitting couplers and receiving couplers disclosed in the first to fourth embodiments may be configured with an FR4 substrate, a Teflon substrate, a ceramic substrate, or a flexible substrate.

[0076] In addition, in order to correct the impedance in each of the connection parts disclosed in the first to fourth embodiments, a floating pattern may be disposed near the signal line, and a resistor may be mounted between the floating pattern and the ground conductor to adjust the impedance.

[0077] The wireless transmission system 200 disclosed in any of the first to fourth embodiments may also be capable of transmitting power in addition to communicating wireless signals.

[0078] The present invention can also be realized by supplying a program for implementing one or more of the functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in a computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC, etc.) that implements one or more of the functions. The program may also be provided by recording it on a computer-readable storage medium. [Explanation of symbols]

[0079] 200 Wireless Transmission System 201 Transmitter 202 Receiver 203 Transmitting circuit 204 Transmitting Coupler 205 Receiving circuit 206 Receiving Coupler 207 First transmitting coupler 208 Second transmitting coupler 209 Connection 210 First signal line 211 Second signal line 212 First Ground Conductor 213 Third Signal Line 214 4th Signal Line 215 Second Ground Conductor 216 First Termination Resistor 217 Second Termination Resistor 218 5th Signal Line 219 6th Signal Line 220 Third Ground Conductor

Claims

1. 1. A wireless transmission system, comprising: a first coupler having a plurality of substrates; a second coupler for transmitting a signal by electric and / or magnetic field coupling with the first coupler; and a substrate of each of the first couplers includes a signal line and a ground; the signal lines of the first substrate and the second substrate of the first coupler are connected via a first conductor; A wireless transmission system characterized in that the ground of the first substrate and the ground of the second substrate are connected via a second conductor, and the width of the signal line of the first substrate, the width of the signal line of the second substrate, and the width of the first conductor are approximately equal.

2. 2. The wireless transmission system according to claim 1, wherein the signal line and the ground formed on the substrate of the first coupler are formed on different surfaces of the substrate.

3. 3. The wireless transmission system according to claim 1, wherein the first conductor and the second conductor are arranged on different planes.

4. A wireless transmission system described in any one of claims 1 to 3, characterized in that each signal line of the first substrate and the second substrate is connected to the first conductor by solder.

5. A wireless transmission system described in any one of claims 1 to 4, characterized in that each signal line of the first substrate and the second substrate is a line that transmits a differential signal.

6. A method for controlling a wireless transmission system, comprising: A first coupler having a plurality of substrates and a second coupler; a signal line of a first substrate included in the plurality of substrates is connected to a signal line of a second substrate included in the plurality of substrates via a first conductor having a width substantially equal to that of the signal line, and a ground of the first substrate and a ground of the second substrate are connected via a second conductor; The first coupler and the second coupler transmit a signal by electric field / magnetic field coupling. The control method according to claim 1, further comprising a transmitting step of transmitting the control signal to the control device.

7. A program for causing a computer to control a wireless transmission system by the control method according to claim 6.

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