Communication Equipment

Abstract

To reduce interference between transmission lines while suppressing substrate deformation.SOLUTION: A communication device 10 includes a substrate 101 having transmission lines 102, 103, a metal part 104 that functions as a ground to the substrate 101 and is located through a space between the transmission lines 102, 103, and an insulator 106 disposed on one side of the substrate 101 that serves as a displacement direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a communication device. [Background technology]

[0002] There is a known communication system that uses electromagnetic coupling to perform wireless communication between nearby devices. In such a communication system, the geometric relationship between the transmission line on the transmitting side and the transmission line on the receiving side affects the communication quality. In particular, when the transmission line is provided on a flexible substrate, the transmission line may be deformed if the substrate is bent due to aging or external force, which may result in a deterioration of the communication quality. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-152356 A Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 discloses a board holding structure that can prevent damage to a board by sandwiching the board between cushioning materials. However, a board holding structure that sandwiches the board between cushioning materials has an issue in that the coupling between the transmission lines becomes strong due to the relative dielectric constant of the cushioning material, which increases interference and degrades communication quality. [Means for solving the problem]

[0005] The communication device of the present invention is provided with a substrate having a transmission line, and a ground for the transmission line. At least some A metal part disposed with a space therebetween; On the surface of the substrate opposite to the surface on which the metal portion is disposed and an insulator disposed overlying the substrate. Effect of the Invention

[0006] According to the present invention, it is possible to reduce interference between transmission lines while suppressing deformation of the substrate. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram illustrating an example of a configuration of a communication device according to a first embodiment. [Diagram 2] FIG. 11 is a diagram illustrating an example of a configuration of a communication device according to a second embodiment. [Diagram 3] FIG. 11 is a diagram illustrating an example of the configuration of a communication device according to a third embodiment. [Figure 4] FIG. 13 is a diagram illustrating an example of the configuration of a communication device according to a fourth embodiment. [Diagram 5] FIG. 13 is a diagram illustrating an example of the configuration of a communication device according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. [First embodiment] FIG. 1 is a diagram showing an example of the configuration of communication devices 100 and 200 according to the first embodiment. The communication devices 100 and 200 perform wireless communication using electromagnetic field coupling between transmission lines, which will be described later. Note that the electromagnetic field coupling in this embodiment includes both electric field coupling and magnetic field coupling. That is, wireless communication between the transmission lines may be performed by electric field coupling, magnetic field coupling, or both electric field coupling and magnetic field coupling.

[0009] FIG. 1A is a cross-sectional view showing an example of the configuration of a communication system 10. As shown in FIG. The communication system 10 includes a communication device 100 on the transmitting side and a communication device 200 on the receiving side.

[0010] First, the transmitting communication device 100 will be described. The transmitting communication device 100 has a configuration that is long along the direction perpendicular to the plane of the paper shown in Fig. 1(a). The transmitting communication device 100 includes a substrate 101, a metal part 104, and an insulator 106. The substrate 101 is a flexible printed circuit board having flexibility. For example, materials such as polyimide, polyester, and liquid crystal polymer are used for the substrate 101. The substrate 101 has flat upper and lower surfaces and is flexible in a direction perpendicular to the upper and lower surfaces. Here, the direction perpendicular to the upper and lower surfaces of the substrate 101 is the displacement direction of the substrate 101. In the transmitting communication device 100 of this embodiment, two substrates 101 are arranged adjacent to each other in parallel along the longitudinal direction. However, three or more substrates 101 may be arranged adjacent to each other in parallel, and multiple substrates 101 may be integrally configured.

[0011] The substrate 101 has transmission lines 102 and 103. The transmission lines 102 and 103 are formed as patterns on the substrate 101. The transmission lines 102 and 103 are transmission lines on the transmitting side that transmit wireless signals to transmission lines 202 and 203 of a receiving communication device 200, respectively. The transmission lines 102 and 103 function as transmitting couplers that transmit wireless signals. The transmission lines 102 and 103 are linear conductor members. The transmission lines 102 and 103 are made of, for example, copper or other material. In the present embodiment, the transmission lines 102 and 103 are each configured as a transmission line for differential transmission by arranging two linear conductor members in parallel along the longitudinal direction on one substrate 101. Note that the present embodiment is not limited to a configuration in which each substrate 101 has a transmission line, and one substrate 101 may have the transmission lines 102 and 103.

[0012] The metal part 104 is a reference potential for the transmission lines 102 and 103 on the transmitting side. The metal part 104 functions as a ground with respect to the substrate 101. The metal part 104 is arranged on one side of the substrate 101 in the displacement direction with a space between the transmission lines 102 and 103. Specifically, the metal part 104 has a substantially U-shaped cross section, a space is formed in the center in the width direction, and both ends in the width direction are connected to the substrate 101. In the transmitting communication device 100 of this embodiment, two metal parts 104 are arranged adjacent to each other in parallel along the longitudinal direction. However, three or more metal parts 104 may be arranged adjacent to each other in parallel, and multiple metal parts 104 may be integrally formed.

[0013] Moreover, metal part 104 is connected to substrate 101 by fixing member 105. By connecting by fixing member 105, substrate 101 and metal part 104 can be easily aligned and the connection strength can be improved. However, depending on the mechanical constraints of communication device 100, substrate 101 and metal part 104 may be connected without using fixing member 105.

[0014] The insulator 106 suppresses deformation of the substrate 101 due to an external force. For example, the insulator 106 is made of a material such as polyethylene or insulating foam. The insulator 106 is disposed on one side of the substrate 101 in the displacement direction, that is, on the side (lower surface) on which the metal part 104 is disposed. Specifically, the insulator 106 is disposed between the substrate 101 and the metal part 104, in a space formed in the metal part 104. Therefore, when viewed in the up-down direction, the insulator 106 and the transmission line 102, and the insulator 106 and the transmission line 103 are positioned so as to overlap each other. The insulator 106 is bonded to the substrate 101 via an adhesive 107. The adhesive 107 is positioned between the substrate 101 and the insulator 106, as well as between the substrate 101 and the metal part 104. Therefore, the metal part 104 is bonded to the substrate 101 via the adhesive 107.

[0015] Fig. 1(b) is a diagram showing an example of another configuration of the transmitting-side communication device 100. Note that the configurations described in Fig. 1(a) are given the same reference numerals and descriptions thereof will be omitted. The communication device 100 has a signal source 108, a differential transmission buffer 109, and a termination resistor 111. Data output from the signal source 108 is input as a differential signal via the differential transmission buffer 109 connected to one end of the transmission line 102. The other end of the transmission line 102 is terminated by a termination resistor 111 having approximately the same characteristic impedance as the transmission line 102 on the transmitting side. The transmission line 103 side has the same configuration as the transmission line 102 side.

[0016] Next, a description will be given of the receiving communication device 200. The receiving communication device 200 has a configuration along the direction perpendicular to the plane of the paper shown in Fig. 1(a). The receiving communication device 200 includes a substrate 201. The substrate 201 is a flexible printed circuit board having flexibility. For example, the substrate 201 is made of a material such as polyimide, polyester, or liquid crystal polymer. The top and bottom surfaces of the substrate 201 are flat. The substrate 201 is disposed with a gap between it and the transmitting communication device 100. Specifically, the substrate 201 is disposed on the opposite side of the metal part 104 with respect to the substrate 101 of the communication device 100, with a space between the substrate 101 and the substrate 101. The substrate 201 is configured to be movable parallel to the substrate 101, i.e., along a direction perpendicular to the paper surface.

[0017] The substrate 201 has transmission lines 202 and 203. The transmission lines 202 and 203 are formed as patterns on the substrate 201. The transmission lines 202 and 203 are transmission lines on the receiving side that receive wireless signals from the transmission lines 102 and 103 of the communication device 100 on the transmitting side, respectively. When viewed in the up-down direction, the transmission lines 202 and 102 at least partially overlap, and the transmission lines 203 and 103 at least partially overlap. When the substrate 201 moves parallel to the substrate 101, the transmission line 202 moves along the transmission line 102, and the transmission line 203 moves along the transmission line 103. The transmission line 202 receives a wireless signal from the transmission line 102, and the transmission line 203 receives a wireless signal from the transmission line 103. The transmission lines 202 and 203 function as receiving couplers that receive wireless signals. With this configuration, wireless communication can be performed between the transmission lines 102, 103 and the transmission lines 202, 203 even while the substrate 201 is moving relative to the substrate 101. The transmission lines 202, 203 of this embodiment each constitute a transmission line for differential transmission by arranging two linear conductor members in parallel along the longitudinal direction on one substrate 201. Note that the configuration is not limited to one in which each substrate 201 has its own transmission line, and one substrate 201 may have multiple transmission lines.

[0018] Fig. 1(c) is a diagram showing an example of another configuration of the receiving-side communication device 200. Note that the configurations described in Fig. 1(a) are given the same reference numerals and descriptions thereof will be omitted. The communication device 200 includes a comparator 204 and a termination resistor 205. A signal output from one end of the transmission line 202 is waveform-shaped by the comparator 204 and then detected as a received signal. The transmission line 203 side has the same configuration as the transmission line 202 side.

[0019] Here, in the transmitting communication device 100 configured as described above, the insulator 106 is disposed within the space of the metal part 104 and is connected to the substrate 101, so that deformation of the substrate 101 due to external forces can be suppressed.

[0020] On the other hand, the strength of interference between transmission line 102 and transmission line 103, and between transmission line 102 and transmission line 203 is proportional to the capacitance C between the transmission lines given by the following equation, where S is the area of ​​the electrode, d is the distance between the electrodes, and ε is the dielectric constant between the electrodes. C = εS / d (1)

[0021] In addition, ε is the relative dielectric constant of the insulator. r If the dielectric constant of air is ε0, it is given by the following equation. ε = ε r ε0 (2) Here, ε0 = 8.85 × 10 -12 [F / m], ε r is about 1.4 to 3.0 for materials such as polyethylene and insulating foam that are commonly used as cushioning materials, and is 1.0 for air. In other words, compared to the conventional configuration in which the board is sandwiched between insulators, the configuration in which board 101 is placed in contact with metal part 104 and insulator 106 has a higher relative dielectric constant ε r This reduces the interference between the transmission lines. In addition, by using an adhesive 107 with a low dielectric constant for connecting the insulator 106 to the substrate 101, the interference can be further reduced.

[0022] As described above, the communication device 100 of the present embodiment includes the substrate 101 having the transmission lines 102 and 103, the metal part 104 disposed between the substrate 101 and the transmission lines 102 and 103 with a space therebetween, and the insulator 106 disposed on one side of the substrate 101. Therefore, it is possible to suppress deformation of the substrate 101 due to an external force, and to reduce interference between the transmission lines 102 and 103 and between the transmission lines 102 and 203. In addition, when viewed in the vertical direction, the insulator 106 and the transmission line 102, and the insulator 106 and the transmission line 103 are positioned overlapping along the transmission lines 102 and 103, respectively, thereby suppressing deformation of the transmission lines.

[0023] In the above embodiment, the case where each transmission line is a differential microstrip line has been described, but the present invention is not limited to this. For example, the transmission lines 202 and 203 of the receiving communication device 200 may be capacitive transmission lines that have no termination resistor 205 and are open-ended, or may be inductive transmission lines in which the termination resistor 205 is short-circuited. In the above-mentioned embodiment, the transmission lines 102 and 103 function as a transmitting coupler for transmitting a radio signal, and the transmission lines 202 and 203 function as a receiving coupler for receiving a radio signal, but this is not limited to the above. Since a directional coupler consisting of a transmitting coupler and a receiving coupler has reversibility, the transmitting side and the receiving side can be interchanged by changing the circuit connected to the transmission lines 102 and 103 and the circuit connected to the transmission lines 202 and 203. The transmitting side and the receiving side can be interchanged in this manner in the following embodiments as well.

[0024] [Second embodiment] Next, a communication device 300 according to a second embodiment will be described. The following description will focus on the differences from the first embodiment, and similar configurations will be given the same reference numerals and descriptions thereof will be omitted as appropriate. FIG. 2 is a cross-sectional view of communication devices 300 and 200 according to the second embodiment. The transmitting communication device 300 differs from the first embodiment in the arrangement of the insulator 306. The insulator 306 is arranged on one side of the substrate 101 in the displacement direction, and is arranged on the surface (upper surface) opposite to the surface on which the metal part 104 is arranged. The insulator 306 is arranged to face the substrate 201 across a space. The insulator 306 is also bonded to the entire surface of the substrate 101 via an adhesive 307. The metal part 104 is also connected to the substrate 101 by the fixing member 105. At this time, the fixing member 105 connects the insulator 306 to the substrate 101 together with the metal part 104. In this embodiment, since the insulator 306 is connected to the substrate 101, deformation of the substrate 101 due to an external force can be suppressed.

[0025] Unlike the first embodiment, the insulator 306 of this embodiment is not disposed between the substrate 101 and the metal part 104. Here, the signal strength in the electromagnetic field communication between the transmission line 102 and the transmission line 202 is proportional to the width of the transmission line. One method for widening the width of the transmission line while keeping the characteristic impedance of the transmission line constant is to lower the relative dielectric constant between the transmission line and the ground. That is, by eliminating the insulator between the substrate 101 and the metal part 104, the relative dielectric constant between the substrate 101 and the metal part 104 can be reduced compared to the conventional configuration in which the substrate is sandwiched between the insulators, and the width of the transmission line under the same impedance conditions can be widened. By widening the width of the transmission line, the coupling between the transmission line 102 and the transmission line 202 can be strengthened, and the signal strength in wireless communication can be strengthened.

[0026] [Third embodiment] Next, a communication device 400 according to the third embodiment will be described. In the following, differences from the second embodiment will be mainly described, and descriptions of similar configurations will be omitted as appropriate. FIG. 3 is a cross-sectional view of communication devices 400 and 200 according to the third embodiment. The shape of the insulator 406 of the transmitting communication device 400 is different from that of the second embodiment. The insulator 406 is disposed on one side of the substrate 101 in the displacement direction, and is disposed on the opposite side (upper surface) to the side on which the metal part 104 is disposed. The insulator 406 of this embodiment is provided with a groove 407 that is partially cut out in the region between the transmission line 102 and the transmission line 103. The groove 407 is cut out in a concave shape from the upper surface downward so as to have a rectangular parallelepiped shape. However, the shape and size of the groove 407 are not limited. In addition, the groove 407 is continuously provided along the transmission lines 102 and 103. However, the groove 407 is not limited to being continuously provided, and may be provided intermittently.

[0027] In this manner, in the communication device 400 of the present embodiment, the groove 407 is provided in the insulator 406 in the region between the transmission line 102 and the transmission line 103, so that air can be interposed in the space within the groove 407. Therefore, the relative dielectric constant ε r This reduces interference between the transmission lines, and therefore reduces interference between the transmission lines 102 and 103 and between the transmission lines 102 and 203. Furthermore, in the communication device 400 of this embodiment, the grooves 407 in the insulator 406 can be formed by, for example, shape processing, and therefore the manufacturing cost can be reduced.

[0028] [Fourth embodiment] Next, a communication device 500 according to a fourth embodiment will be described. In the following, differences from the first embodiment will be mainly described, and descriptions of similar configurations will be omitted as appropriate. Fig. 4(a) is a cross-sectional view of communication devices 500 and 200 according to the fourth embodiment. Fig. 4(b) is a perspective view showing a part of the communication devices 500 and 200. The communication device 500 differs from the first embodiment in the shape of the metal part 504. The metal part 504 of this embodiment is provided with a convex protruding part 505 that protrudes above the upper surface of the substrate 101 in the region between the transmission line 102 and the transmission line 103. The protruding part 505 is formed to have a rectangular parallelepiped shape. However, the shape and size of the protruding part 505 are not limited. The protruding part 505 is also provided intermittently along the transmission lines 102 and 103. However, the protruding part 505 is not limited to being provided intermittently, and may be provided continuously. The protruding part 505 may be formed integrally with the metal part 504, or a separate protruding part 505 may be connected to the metal part 504.

[0029] In this manner, the communication device 500 of the present embodiment can block electromagnetic waves between the transmission line 102 and the transmission line 103 and between the transmission line 102 and the transmission line 203 by providing the protruding portion 505 in the metal portion 504 in the region between the transmission line 102 and the transmission line 103. This can also reduce interference between the transmission lines, and therefore can reduce interference between the transmission line 102 and the transmission line 103 and between the transmission line 102 and the transmission line 203. Note that the higher the protruding portion 505 is, the more interference can be reduced. Furthermore, the communication device 500 of the present embodiment can provide multiple transmission lines on a single board, improving ease of assembly.

[0030] [Fifth embodiment] Next, a communication system 20 according to the fifth embodiment will be described. The following description will focus on the differences from the first embodiment, and the same components are denoted by the same reference numerals and the description will be omitted as appropriate. 5 is a perspective view of a communication system 20 according to a fifth embodiment. In this embodiment, the communication system 20 is a device including a rotation mechanism 610 that rotates about a rotation axis O. The communication system 20 includes a transmitting communication device 600, a receiving communication device 200, and a rotation mechanism 610. The device including the rotation mechanism 610 can be used for various purposes such as an arm portion of a robot.

[0031] A transmitting communication device 600 includes a substrate 601, a metal part 604, and an insulator. The substrate 601 is a flexible printed circuit board having flexibility. The substrate 601 of this embodiment is formed to be curved into a cylindrical shape by bringing one end and the other end in the longitudinal direction close to each other. The substrate 601 has transmission lines 602 and 603. The transmission lines 602 and 603 are arranged in parallel along the circumferential direction of the substrate 601.

[0032] Metal part 604 is disposed on one side of substrate 601 in the displacement direction with a space between it and transmission lines 602 and 603. Metal part 604 is connected along the inner side surface of cylindrical substrate 601, and is formed in a cylindrical shape similar to substrate 601. The insulator is disposed at a position relative to the substrate 601 similar to that in any one of the first to fourth embodiments described above.

[0033] The receiving communication device 200 has a substrate 201. The substrate 201 is disposed on the opposite side of the metal part 604 with respect to the substrate 601 of the transmitting communication device 600, with a space therebetween. The substrate 201 has the same configuration as in the first embodiment.

[0034] The rotation mechanism 610 has a rotating part that rotates around the rotation axis O, and a fixed part that is fixed and does not rotate. In this embodiment, the rotating part of the rotation mechanism 610 is connected to the transmitting communication device 600, and the fixed part of the rotation mechanism 610 is connected to the receiving communication device 200. Therefore, the transmitting communication device 600 can rotate around the rotation axis O. According to the communication system 20 configured in this manner, the substrate 601 and the metal part 604 are rotated around the rotation axis O by the rotation mechanism 610, so that electromagnetic field communication can be performed while moving in a rotational manner.

[0035] In the communication system 20 of this embodiment, the rotation mechanism 610 rotates the substrate 601 of the communication device 600, so that centrifugal force is applied to the substrate 601. Therefore, the substrate 601 tries to deform outward around the rotation axis O, but since an insulator is connected to the substrate 601, it is possible to suppress the deformation of the substrate 601 due to the centrifugal force. Note that, by arranging the insulator at a position similar to that of any of the first to fourth embodiments with respect to the substrate 601, it is possible to reduce interference between the transmission line 102 and the transmission line 103 and between the transmission line 102 and the transmission line 203.

[0036] As described above, the present invention is determined by the claims and is not limited by the above-mentioned embodiments. Moreover, not all combinations of features described in the above-mentioned embodiments are necessarily essential to the present invention. Moreover, the contents described in the specification and drawings are merely examples and should not be considered as limiting the present invention. Moreover, various modifications (including organic combinations of the respective embodiments) are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention. In other words, all configurations that combine the above-mentioned respective embodiments and their modifications are included in the present invention. [Explanation of symbols]

[0037] 10, 20: communication system 100, 300, 400, 500, 600: transmitting communication device 101: substrate 102, 103: transmission line 104, 604: metal part 106, 306, 406: insulator 407: groove 505: protrusion

Claims

1. A substrate having a transmission line; a metal portion that functions as a ground of the transmission line and is at least partially disposed between the metal portion and the substrate via a space; an insulator disposed on a surface of the substrate opposite to a surface on which the metal portion is disposed, the insulator being disposed so as to overlap the substrate; A communication device comprising:

2. the substrate has a plurality of the transmission lines; The insulator is 2. The communication device according to claim 1, further comprising a groove provided in an area between the plurality of transmission lines.

3. the substrate has a plurality of the transmission lines; The metal part is 3. The communication device according to claim 1, further comprising a protrusion protruding from the substrate toward a different communication device disposed across a space from the substrate in an area between the plurality of transmission lines.

4. A substrate having a plurality of differential transmission lines extending in a predetermined direction; a metal portion that functions as a ground for the plurality of differential transmission lines and has at least a portion that is disposed with a space between it and the substrate in a plane perpendicular to the predetermined direction; an adhesive portion disposed between the substrate and the metal portion; Equipped with A communication device, wherein the dielectric constant of the adhesive portion is smaller than the dielectric constant of the substrate.

5. The substrate is 5. The communication device according to claim 1, wherein the communication device is formed to be curved in a cylindrical shape and is rotatable about a rotation axis.

6. 6. The communication device according to claim 1, wherein communication is performed by electromagnetic coupling with a different communication device disposed across a space from the substrate.

7. The insulator is 4. The communication device according to claim 1, wherein the communication device is connected to the substrate via an adhesive.

8. The substrate is 8. The communication device according to claim 1, wherein the communication device is a flexible printed circuit board.

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