Method for manufacturing a communication path and coaxial waveguide converter

Abstract

To provide a communication path that requires no installation work and enables communication over relatively long distances.SOLUTION: A method for manufacturing a communication path includes a coaxial waveguide converter installation step of installing coaxial waveguide converters at both ends of an electric conduit so as to perform high frequency coupling between the coaxial line that transmits high frequencies and a waveguide that transmits high frequencies using the existing metal conduit as the waveguide.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present application relates to a method for manufacturing a communication path and a coaxial-waveguide converter used in the method for manufacturing the communication path. [Background technology]

[0002] It has been proposed to use existing metal objects within a building to induce high-frequency currents, which act as high-frequency propagation paths to inject high-frequency waves into rooms in the building, and to use the walls surrounding the rooms as waveguides to perform evanescent communication (see, for example, Patent Document 1).

[0003] On the other hand, in wireless transmission systems that use dedicated waveguides for transmitting microwaves, flanges are used to connect waveguides together or to connect with coaxial waveguides in order to ensure good electrical contact in order to minimize the propagation loss of electromagnetic waves. Therefore, the components that make up the waveguide path are generally expensive. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-30494 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-88797 Summary of the Invention [Problem to be solved by the invention]

[0005] The method described in Patent Document 1 does not require the installation of a communication path, but instead uses an existing structure, so installation costs are low, but it can only be used for communication within a room in a building and cannot be used for long-distance communication.

[0006] In addition, when transmitting microwaves using a dedicated waveguide, the positions of the antenna and reflector at the coaxial-waveguide converter that connects the coaxial line and the waveguide are generally adjusted at the factory to ensure good coupling between the coaxial mode and the waveguide mode before being installed on-site, which makes it difficult to achieve optimal coupling performance suited to the local environment.Furthermore, the waveguide and coaxial-waveguide converter require the use of expensive dedicated equipment, and installation costs are generally high.

[0007] Although a coaxial waveguide conversion unit with a structure that allows for flexible configuration has already been proposed (see, for example, Patent Document 2), it is only capable of connecting to a dedicated waveguide, and has not yet achieved a reduction in the installation cost of the entire waveguide route or the ability to provide optimal functionality suited to the site.

[0008] The present invention is intended to solve the above-mentioned problems, and has an object to provide a communication path that does not require construction work and enables communication over relatively long distances. [Means for solving the problem]

[0009] The method for manufacturing a communication path disclosed in the present application includes: The wires are not stored The method includes a coaxial-waveguide converter mounting step of mounting a coaxial-waveguide converter on each end of an existing electric conduit to convert the electric conduit into a waveguide for transmitting high frequencies and to high-frequency-couple the coaxial line for transmitting high frequencies to the waveguide. [Effects of the Invention]

[0010] According to the manufacturing method of the communication path disclosed in the present application, by utilizing an existing electrical conduit as a waveguide, which is a high-frequency transmission line, it is possible to provide a communication path that does not require construction work and enables communication over relatively long distances. [Brief explanation of the drawings]

[0011] [Figure 1] 3 is a schematic configuration diagram of a communication path for illustrating a method for manufacturing a communication path according to the first embodiment. FIG. [Figure 2]4 is a flowchart showing a method for manufacturing a communication path according to the first embodiment. [Figure 3] FIG. 10 is a schematic configuration diagram of a communication path for explaining a method for manufacturing a communication path according to a second embodiment. [Figure 4] FIG. 10 is a schematic configuration diagram of another communication path for illustrating a method for manufacturing a communication path according to the second embodiment. [Figure 5] FIG. 10 is a cross-sectional view showing a schematic configuration of a coaxial-waveguide converter according to a third embodiment. [Figure 6] FIG. 11 is a perspective view showing the structure of a probe of a coaxial-waveguide converter according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Embodiment 1 FIG. 1 is a schematic diagram of a communication path for explaining a manufacturing method of a communication path according to a first embodiment, and FIG. 2 is a flowchart showing a manufacturing method of a communication path. In FIG. 1, coaxial-waveguide converters 30 are attached to both ends of conduit 21 used as a communication path. Conduit 21 is an existing metal conduit, and the electric wire housed inside conduit 21 has been removed so that it functions as a waveguide. Coaxial-waveguide converter 30 has the function of coupling the coaxial mode of connected coaxial line 22 with the waveguide mode of conduit 21 functioning as a waveguide. High-frequency communication device 40 is connected to the other end of coaxial line 22. High-frequency communication device 40 is a high-frequency transceiver when performing two-way communication, and is a high-frequency transmitter on one side and a high-frequency receiver on the other side when performing only one-way communication.

[0013] Next, a manufacturing method of a communication path according to the first embodiment will be described with reference to FIGS. 1 and 2. The conduit 21 is a metal conduit 21 that has already been laid inside a building, outside a building, underground, or the like. In the present application, this existing conduit 21 is made to function as a waveguide, which is a high-frequency transmission path. Therefore, if an electric wire is still housed in the conduit 21, the electric wire is removed (step ST1). If the electric wire has already been removed, step ST1 is omitted. Next, a coaxial-waveguide converter 30 is attached to each end of the conduit 21 (step ST2). After the coaxial-waveguide converter 30 is attached, the high-frequency coupling state of the coaxial-waveguide converter 30 is adjusted (step ST3). If the coupling state between the waveguide mode of the conduit 21 and the coaxial mode of the coaxial line side of the coaxial-waveguide converter 30 has been adjusted in advance, step ST3 can be omitted.

[0014] In this way, the existing electrical conduit 21 can function as a waveguide, which is a high-frequency transmission path. Therefore, a communication path can be established without laying a new waveguide, making it easy to create a communication path. For example, in large plants such as power plants, waveguides can be used to replace existing wiring. Power plants generally use metal wires to transmit information via electrical signals. However, due to the large number of sensors and actuators to be controlled (thousands to tens of thousands), the total length of these wires can reach thousands of kilometers in a single plant. The cost of laying the wiring can sometimes account for several tens of percent of the plant construction cost. Furthermore, power plants sometimes restrict the use of flammable materials in their equipment for safety reasons. Since the sheaths of electrical wires are flammable, removing the metal wires and reusing the remaining conduit as a waveguide can eliminate signal degradation due to interference between metal wires and also have the secondary effect of removing flammable materials from the equipment.

[0015] Embodiment 2 FIG. 3 is a schematic configuration diagram of a communication path manufactured by the manufacturing method of a communication path according to the second embodiment. In the first embodiment, the communication path is configured such that a coaxial-waveguide converter 30 is attached to each end of a single continuous electrical conduit 21. In the second embodiment, a case will be described in which the communication path uses a plurality of continuous electrical conduits. FIG. 3 shows a configuration in which two continuous electrical conduits are used as an example. In FIG. 3, the electrical conduit 210 and the electrical conduit 211 each have a coaxial-waveguide converter 30 attached to both ends. The manufacturing method for attaching the coaxial-waveguide converters 30 to the electrical conduit 210 and the electrical conduit 211 to form a communication path is the same as that described in FIG. 2 of the first embodiment. The coaxial-waveguide converter 30 attached to one end of the electrical conduit 210 and the coaxial-waveguide converter 30 attached to one end of the electrical conduit 211 are connected to each other by a coaxial line 23. High frequency communication devices 40 are connected to the coaxial waveguide converters 30 attached to the other ends of the conduits 210 and 211 via coaxial lines 22, respectively.

[0016] FIG. 4 is a schematic diagram of another communication path manufactured by the manufacturing method of a communication path according to the second embodiment. The communication path shown in FIG. 4 has three continuous conduits. One of the coaxial-waveguide converters 30 connected to both ends of conduit 212 of the three conduits is connected to a coaxial-waveguide converter 30 connected to one end of conduit 210 via coaxial line 23, and the other coaxial-waveguide converter 30 is connected to a coaxial-waveguide converter 30 connected to one end of conduit 211 via coaxial line 24. Each conduit is manufactured by the method for manufacturing a communication path using a conduit described in the first embodiment with reference to FIG. 2. In this way, a longer communication path can be achieved by using three or more conduits as the communication path and connecting the conduits with coaxial lines.

[0017] As described above, by connecting multiple electrical conduits with a coaxial line via a coaxial-waveguide converter connected to the end of the electrical conduits, it is possible to combine distant electrical conduits into a single communication path, thereby forming a longer communication path.

[0018] Embodiment 3 In the third embodiment, an example of the configuration of a coaxial-waveguide converter used in the manufacturing method of the communication path described in the first or second embodiment will be described. FIG. 5 is a cross-sectional view showing the configuration of a coaxial-waveguide converter 30 connected to a conduit 21. The conduit 21 has a circular cross section perpendicular to the conduit axis, and the coaxial-waveguide converter housing 1 also has a circular cross section perpendicular to the conduit axis. FIG. 5 shows a cross section including the conduit 21 and the waveguide portion of the coaxial-waveguide converter 30. The coaxial-waveguide converter 30 includes a coaxial-waveguide converter housing 1, a reflector 2 fixed to a reflector shaft 3, a coaxial line connecting portion 13 fixed to a probe 12, and an inner wall shielding plate 11 and an outer wall shielding plate 10 fixed to the probe 12. The coaxial line connection part 13, inner wall shielding plate 11, and outer wall shielding plate 10 are fixed to the probe 12 and are movable together with the probe 12 in the axial direction of the coaxial-waveguide converter housing 1. The coaxial-waveguide converter housing 1 has a slot hole 14, and the probe 12 moves along the slot hole 14 while penetrating the slot hole, i.e., the side wall of the waveguide part.

[0019] Because the coaxial-waveguide converter housing 1 uses the electrical conduit 21 as a waveguide, the inner diameter A and outer diameter B of the coaxial-waveguide converter housing 1 are set to match the inner and outer diameters of a typical electrical conduit. To reduce reflection loss at the connection between the coaxial-waveguide converter 30 and the electrical conduit 21, which functions as a waveguide, it is desirable to match at least the inner diameter. The outer diameter of the coaxial-waveguide converter housing 1 does not necessarily have to match the outer diameter of the electrical conduit, but matching the outer diameters allows the electrical conduit 21 used as a waveguide to be attached and connected to the coaxial-waveguide converter housing 1 using a threadless coupling 20 for connecting the electrical conduit. By using off-the-shelf products for the electrical conduit 21 and the threadless coupling 20 for connecting the electrical conduit, it is possible to construct a waveguide line using existing equipment.

[0020] 6 is a diagram showing parts fixed relatively to the probe 12. The shape of the inner wall shielding plate 11 is a curved shape that is part of a circle concentric with the coaxial-waveguide converter housing 1, and the outer bending radius E of the inner wall shielding plate 11 is set to a value that coincides with 1 / 2 of the inner diameter A of the coaxial-waveguide converter housing 1 shown in FIG.

[0021] The shape of the outer wall shielding plate 10 is also a curved shape that is part of a concentric circle with respect to the coaxial-waveguide converter housing 1, and the inner bending radius F of the outer wall shielding plate 10 is set to a value that is equal to 1 / 2 of the outer diameter B of the coaxial-waveguide converter housing 1 shown in Figure 5.

[0022] Furthermore, a reflector shaft 3 is fixed to the reflector 2, and the reflector 2 is able to slide in the tube axis direction while maintaining contact with the inner wall of the coaxial-waveguide converter housing 1. For example, the reflector 2 is provided with contacts on its periphery that come into contact with the coaxial-waveguide converter housing 1, and the reflector shaft 3 has a screw structure that penetrates the housing that forms the end of the waveguide part of the coaxial-waveguide converter 30. By turning the reflector shaft 3, the reflector 2 can slide in the tube axis direction while rotating while maintaining contact with the inner wall of the coaxial-waveguide converter housing 1.

[0023] Next, the operation will be explained. In the operation during transmission, in Fig. 5, the high frequency current supplied from the coaxial line connection part 13 is converted into an electromagnetic wave by the probe 12 and is radiated into the coaxial-waveguide converter 30. The positional relationship is adjusted so that the phase of the electromagnetic wave radiated in the direction of the electromagnetic wave propagation (the direction of the electric conduit 21) and the electromagnetic wave radiated in the direction of the reflector 2 coincide. Specifically, the dimension D is set so that the in-guide wavelength of the high frequency propagating in the waveguide is λ g Then, λ g Set it to / 4.

[0024] The operation during reception is the reverse of the operation during transmission. The electromagnetic waves propagating from the conduit 21 come into direct contact with the probe 12 and are converted into high-frequency current. After passing through the probe 12, the waves are reflected by the reflector 2 and are converted into high-frequency current again by the probe 12.

[0025] The frequency to be used can be set at two locations, at the probe 12 and the reflector 2, allowing for more flexible settings. In addition, the connection to the conduit 21 used as a waveguide is made using a screwless coupling 20, so the direction of polarization can be adjusted by rotating the coaxial waveguide converter housing 1 around its axis.

[0026] As described above, by using the coaxial-waveguide converter 30 having an adjustment mechanism that can adjust the high-frequency coupling state between the coaxial line and the waveguide as shown in FIG. 5 in the method for manufacturing the communication path according to the first or second embodiment, it is possible to perform the step of adjusting the high-frequency coupling state in step ST3 of FIG. 2.

[0027] Although various exemplary embodiments and examples are described in this application, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless modifications not illustrated are contemplated within the scope of the technology disclosed in this specification. For example, this includes cases where at least one component is modified, added, or omitted, and even cases where at least one component is extracted and combined with components of other embodiments.

[0028] Various aspects of the present application will be summarized below as appendices. (Appendix 1) A method for manufacturing a communication path, comprising a coaxial-waveguide converter attachment step of attaching a coaxial-waveguide converter to each end of an existing metal conduit, which is used as a waveguide for transmitting high frequencies, so as to high-frequency couple a coaxial line transmitting high frequencies with the waveguide. (Appendix 2) 2. The method for manufacturing a communication path according to claim 1, wherein in the coaxial-waveguide converter attaching step, a coaxial-waveguide converter is attached to each of both ends of a plurality of the conduits. (Appendix 3) 3. The method for manufacturing a communication path according to claim 2, further comprising, after the coaxial-waveguide converter attaching step, a step of connecting the coaxial-waveguide converter attached to one end of one of the plurality of conduits with the coaxial-waveguide converter attached to one end of another of the plurality of conduits by a coaxial line. (Appendix 4) The method for manufacturing a communication path according to claim 1 or 2, further comprising, after the coaxial-waveguide converter mounting step, a step of adjusting a high-frequency coupling state of the coaxial-waveguide converter. (Appendix 5) A method for manufacturing a communication path according to claim 1 or 2, further comprising the step of removing an electric wire housed in the existing electric conduit before the coaxial-waveguide converter mounting step. (Appendix 6) A coaxial-waveguide converter used in the method for manufacturing a communication path according to any one of Supplementary Notes 1 to 5, A coaxial waveguide converter in which the inner diameter of the waveguide section is equal to the inner diameter of the existing electrical conduit. (Appendix 7) 7. The coaxial-waveguide converter according to claim 6, wherein the outer diameter of the waveguide section is equal to the outer diameter of the existing electrical conduit. (Appendix 8) 8. A coaxial-waveguide converter according to claim 6, further comprising an adjustment mechanism that enables adjustment of a high-frequency coupling state between the coaxial line and the waveguide. (Appendix 9) 9. A coaxial-waveguide converter according to claim 8, further comprising a reflector at an end of the waveguide section that is slidable in the tube axis direction, and a probe that penetrates a side wall of the waveguide section, the probe being fixed by a structure that allows it to move in the tube axis direction. [Explanation of symbols]

[0029] 1 Coaxial waveguide converter housing, 2 Reflector, 12 Probe, 21, 210, 211, 212 Conduit, 23, 24 Coaxial line, 30 Coaxial waveguide converter

Claims

1. A method for manufacturing a communication path, which includes a coaxial-waveguide converter attachment step in which an existing metal conduit that does not contain any electric wires is used as a waveguide that transmits high frequencies, and a coaxial-waveguide converter is attached to each end of the conduit so as to high-frequency couple the coaxial line that transmits high frequencies with the waveguide.

2. The method for manufacturing a communication path according to claim 1 , wherein the coaxial-waveguide converter attaching step attaches the coaxial-waveguide converter to both ends of each of the plurality of conduits.

3. 3. The method for manufacturing a communication path according to claim 2, further comprising, after the coaxial-waveguide converter attaching step, a step of connecting the coaxial-waveguide converter attached to one end of one of the plurality of electrical conduits with the coaxial-waveguide converter attached to one end of another of the electrical conduits by a coaxial line.

4. 3. The method for manufacturing a communication path according to claim 1, further comprising the step of adjusting a high frequency coupling state of the coaxial-waveguide converter after the step of attaching the coaxial-waveguide converter.

5. 3. The method for manufacturing a communication path according to claim 1, further comprising the step of removing the electric wire housed in the existing electric conduit before the step of attaching the coaxial-waveguide converter.

6. A coaxial-waveguide converter used in the method for manufacturing a communication path according to claim 1, A coaxial waveguide converter in which the inner diameter of the waveguide section is equal to the inner diameter of the existing electrical conduit.

7. 7. The coaxial-waveguide converter according to claim 6, wherein the outer diameter of the waveguide section is equal to the outer diameter of the existing electrical conduit.

8. 8. A coaxial-waveguide converter according to claim 6, further comprising an adjustment mechanism for adjusting the high-frequency coupling state between the coaxial line and the waveguide.

9. 9. The coaxial-waveguide converter according to claim 8, further comprising a reflector at an end of the waveguide section that is slidable in the axial direction of the waveguide section, and a probe that penetrates a side wall of the waveguide section, the probe being fixed in a structure that allows it to move in the axial direction of the waveguide section.

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