JP2012204846A - Leakage coaxial cable device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a leakage coaxial cable device which prevents the increase of the manufacturing cost and keeps the construction costs for the installation, move, exchange, and the like low.SOLUTION: A leakage coaxial cable device includes: a leakage coaxial cable (LCX) 1 where an external conductor, having a central conductor, an insulator, and a slot part formed therein, and a sheath are arranged so as to form a coaxial structure; and a movable case 2 housing the LCX1.

Description

  The present invention relates to a leaky coaxial cable device, and more particularly, to a leaky coaxial cable device including a leaky coaxial cable stored in a specific method.

  As shown in FIG. 11, a leaky coaxial cable (hereinafter referred to as “LCX”) includes an inner conductor 102, an insulator 103, an outer conductor 104, and a jacket (sheath) 105. It is installed along the Shinkansen and is used for wireless communication between the train and the ground, or it is installed in the subway yard and underground mall and used for communication with the ground and fire and radio. In such LCX, periodic slot portions 101 are provided on the outer conductor 104 in order to leak the electromagnetic energy inside the coaxial to the outside.

  That is, the outer conductor 104 of the LCX is provided with a plurality of slot-like slot portions 101 per cycle for every fixed cycle with respect to the cable axis. Each slot 101 is inclined at some angle with respect to the cable axis. When the interval between the slot portions 101 matches the half wavelength of the used frequency or becomes an integral multiple of the half wavelength, the resonance state is established. This frequency is called a resonance frequency.

  Such an LCX is often wound around a drum when shipped from the factory. If the length is short, the drum may not be used and may be wound into a bundle. When using such an LCX, if it is removed from the drum or taken out from the bundle, it will be bent and it will not be easy to make it straight.

  Therefore, as shown in FIG. 12A, the LCX is used by being fixed at an installation place by a fixing jig 106 dedicated to the cable. Since LCX is generally used without being housed, it is fixed as shown in (b) in FIG. 12 as a straight line or a straight line and a curved line according to the place of use. The tool 106 and the fixing bolt 107 were used for fixing. Patent Document 1 describes a support tool dedicated to a cable.

  Patent Document 2, Patent Document 3 and Patent Document 4 describe that the shape of the outer jacket of the LCX has a special structure that can be fixed at a laying place.

JP 2005-130543 A Utility Model Registration No. 2521204 Japanese Patent Laid-Open No. 8-223093 JP 2003-229716 A

  By the way, when the LCX is fixed using the fixing jig 106 as described above or the support described in Patent Document 1, the fixing jig or the support must be used at a plurality of locations. In addition, labor costs associated with fixed work have increased construction costs. Also, once installed, the LCX is firmly fixed by a fixing jig or support, so the construction cost when moving or replacing it for aging or trauma is high. Yes.

  In addition, in the LCX described in Patent Document 2, Patent Document 3 and Patent Document 4, since the outer casing has to be processed into a special shape, the manufacturing cost of the LCX is increased.

  Therefore, the present invention is proposed in view of the above-mentioned circumstances, and the object thereof is to increase the manufacturing cost and to keep the construction cost at the time of facility, movement, replacement, etc. low. An object of the present invention is to provide a leaky coaxial cable device.

  In order to solve the above-described problems and achieve the above object, a leaky coaxial cable device according to the present invention has any one of the following configurations.

[Configuration 1]
The center conductor, the insulator covering the center conductor, and the outer conductor covering the outside of the insulator have a coaxial structure, and a plurality of slots for forming a leakage electromagnetic field are formed in the outer conductor, and the outer conductor is covered with a jacket. It is characterized by comprising an LCX and a movable case containing the LCX.

[Configuration 2]
In the leaky coaxial cable device having the configuration 1, the case is a linear body or a cylindrical body having a curved shape.

[Configuration 3]
In the leaky coaxial cable device having the configuration 1, the case is characterized in that the case is a cylindrical body in which a linear portion and a curved portion are continuous.

[Configuration 4]
In the leaky coaxial cable device having any one of Configurations 1 to 3, the case is characterized in that the case is made of a dielectric.

[Configuration 5]
In the leaky coaxial cable device having any one of Configurations 1 to 4, the LCX is characterized in that a lead cable for connection to an external communication device is connected to one end.

[Configuration 6]
In the leaky coaxial cable device having any one of Configurations 1 to 4, the case has a connection connector directed to the outside at one end, and the connection connector is a connection cable attached to one end of the LCX. Alternatively, it is directly connected to the leaky coaxial cable.

  Since the leaky coaxial cable device according to the present invention having the configuration 1 includes the LCX and a movable case that houses the LCX, the leaky coaxial cable device is also provided in an area where there is no wireless communication environment. You can build a wireless communication environment just by placing it.

  In the leaky coaxial cable device according to the present invention having the configuration 2, since the case is a cylindrical body having a linear shape or a curved shape, the LCX can be easily held in a linear shape or a curved shape. it can.

  In the leaky coaxial cable device according to the present invention having the configuration 3, since the case is a cylindrical body in which the linear portion and the curved portion are continuous, the LCX easily includes the linear portion and the curved portion. It can be held in shape.

  In the leaky coaxial cable device according to the present invention having the configuration 4, since the case is made of a dielectric, transmission and reception of electromagnetic waves between the LCX and the case external space is not hindered.

  In the leaky coaxial cable device according to the present invention having the configuration 5, since the lead cable for connecting to the external communication device is connected to one end of the leaky coaxial cable, the connection between the LCX and the external communication device is Easy to do.

In the leaky coaxial cable device according to the present invention having the configuration 6, the case has a connector for connection toward the outside at one end,
The connection connector is either a connection cable attached to one end of the LCX or directly connected to the leaky coaxial cable, so it is easy to connect the LCX to an external communication device via the connection connector. Can be done.

  That is, the present invention can provide a leaky coaxial cable device that does not increase the manufacturing cost and can suppress the construction cost for facilities, movement, replacement, etc. at a low cost.

It is a perspective view which shows the structure of the leaky coaxial cable apparatus which concerns on this invention. It is a perspective view which shows the structure of LCX which comprises the leaky coaxial cable apparatus which concerns on this invention. It is a three-plane figure which shows the shape of the main-body part of the case which comprises the leaky coaxial cable apparatus which concerns on this invention. It is a three-plane figure which shows the shape of the cover part of the case which comprises the leaky coaxial cable apparatus which concerns on this invention. It is sectional drawing which shows an example of the engagement state of the main-body part and cover part in the case which comprises the leaky coaxial cable apparatus which concerns on this invention. It is a perspective view which shows the measuring system which measures the coupling loss of a leaky coaxial cable apparatus. It is a graph which shows the coupling loss of the leaky coaxial cable apparatus which concerns on this invention. It is a perspective view which shows the other example of the case which comprises the leaky coaxial cable apparatus which concerns on this invention. It is a perspective view which shows the further another example of the case which comprises the leaky coaxial cable apparatus which concerns on this invention. It is a perspective view which shows the structure which provided the connector in the case which comprises the leaky coaxial cable apparatus which concerns on this invention. It is a side view which shows the structure of LCX. It is a perspective view which shows the installation state of the conventional LCX.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing a configuration of a leaky coaxial cable device according to the present invention.

  The leaky coaxial cable device according to the present invention includes an LCX 1 as shown in (a) and (b) of FIG. The LCX 1 has a coaxial structure in which a central conductor, an insulator covering the central conductor, and an outer conductor covering the outside of the insulator are formed, and the outer conductor is covered with a jacket (sheath).

  And this leaky coaxial cable apparatus is provided with the movable case 2 which accommodated LCX1. As shown in FIG. 1A, the case 2 can be a straight cylindrical body (cuboid). Moreover, the case 2 is good also as a curved cylindrical body, as shown to (b) in FIG. Furthermore, case 2 is good also as a cylindrical body with which the linear part and the curved part continued.

  In this leaky coaxial cable device, the LCX 1 is housed in the case 2 so that it can be maintained in a straight line state or a curved state that matches the shape of the case 2 even if it is bent. For example, if the case 2 is linear, the LCX1 is linear. Therefore, the LCX 1 can be formed into a desired shape without using a dedicated fixing jig. Further, the outer cover of the LCX 1 does not need to have a special shape for fixing.

  The case 2 has sufficient rigidity to hold the LCX 1 in a linear state or a curved state, and is not easily deformed. The material of the case 2 is preferably a dielectric material such as a synthetic resin material, not a metal body that reflects electromagnetic waves. By forming the case 2 from a dielectric material, the exchange of electromagnetic waves between the LCX 1 and the external space of the case 2 is not hindered. When forming the case 2 from a synthetic resin material, the case 2 can be easily formed by, for example, an extrusion molding method or an injection molding method.

  This leaky coaxial cable device can be used without being fixed at the place of use. Therefore, it can be carried and used in a desired place. Even in an area where there is no wireless communication environment, it is possible to construct a wireless communication environment simply by carrying this leaky coaxial cable device.

  Further, by forming the case 2 from a dielectric material, the case 2 can be placed between the LCX 1 and the metal even when the place of use is on a metal or a metal member is present in the vicinity. Since they are separated, the transmission / reception performance of the LCX 1 does not deteriorate.

  If the case 2 can be disassembled, the LCX 1 can be easily replaced. For example, the case 2 may be composed of a main body portion and a lid portion, and the main body portion and the lid portion may be fixed with an adhesive. Moreover, you may fix these main-body parts and a cover part with a general screw or a special screw. In either case, it has such a fastness that it does not decompose under normal use conditions, and can be disassembled using a tool or the like if necessary.

  In addition, it is desirable that the lead cable 3 for connecting to the external communication device is connected to the LCX 1 at one end. The lead cable 3 is drawn out of the case 2. A connector 4 is attached to the tip of the lead cable 3.

  Further, the case 2 may be provided with a connector for connection toward the outside at one end. This connector for connection is electrically connected to LCX1 via a connection cable attached to one end of LCX1. Alternatively, the LCX1 connector may be directly connected to the connection connector.

  FIG. 2 is a perspective view showing the configuration of the LCX constituting the leaky coaxial cable device according to the present invention.

  As an example of the present invention, as shown in FIG. 2, a leaky coaxial cable device was configured using LCX1 having a length of 1000 mm, an outer diameter of 7 mm, a coupling loss of 75 dB, and an impedance of 50Ω. A connector 4 having an outer diameter of 15 mm and a length of 30 mm was attached to both ends of the LCX1.

  Then, a common coaxial cable having an outer diameter of 3 mm and a length of 1 m for connecting the LCX 1 and a communication device was connected to the input side of the LCX 1. A 50Ω terminator was connected to the LCX termination side so that unnecessary reflection and leakage did not occur from the termination portion.

  FIG. 3 is a trihedral view showing the shape of the main body of the case constituting the leaky coaxial cable device according to the present invention.

  The material of case 2 was polyethylene. As shown in FIG. 3, the main body 2a of the case 2 has a rectangular parallelepiped shape, a length of 1170 mm, and a cross section of 19 mm × 19 mm. A groove 5 having a width of 8 mm and a depth of 8 mm for accommodating the LCX 1 is provided in the central portion of the main body 2a. Both ends of the groove 5 are expanded to a width of 15 mm and a depth of 15 mm so that the connector portion 4 can be inserted.

  FIG. 4 is a trihedral view showing the shape of the lid of the case constituting the leaky coaxial cable device according to the present invention.

  As shown in FIG. 4, the lid portion 2b of the case 2 is a flat plate having a width of 19 mm, which is the same as the main body, and a thickness of 2 mm.

  FIG. 5 is a cross-sectional view showing an example of the engagement state between the main body and the lid in the case constituting the leaky coaxial cable device according to the present invention.

  As shown in FIG. 5, an engagement recess 7 that engages with an engagement piece 6 provided at the end of the lid 2 b is provided at the end of the body 2 a of the case 2. The lid portion 2b can be fixed by press-fitting into the main body portion 2a by engaging the engagement piece 6 with the engagement recess 7 and can be removed by applying a strong force with a dedicated tool. It can be done.

  FIG. 6 is a perspective view showing a measurement system for measuring the coupling loss of the leaky coaxial cable device.

  Then, LCX1 shown in FIG. 2 was housed in case 2 shown in FIGS. 3 and 4 to form a leaky coaxial cable device, and it was confirmed whether LCX1 functions normally. Case 2 containing LCX 1 was placed on desk 8 as shown in FIG. And the test signal of 2.4 GHz was input into LCX1 with the power Pin (W) from the transmitter 9.

  The half-wavelength standard dipole antenna A was moved along the LCX 1 at a position 1.5 m above the LCX 1, and the antenna output Pout (W) at that time was measured by the receiver 10.

  A coupling loss Lc representing the radiation performance of LCX1 was measured from Pin and Pout. The coupling loss Lc is the ratio of the input power Pin to the LCX1 and the output power Pout from the half-wavelength standard dipole antenna A arranged outside the LCX1, and Lc = −10 log (Pout / Pin) (dB) Can be calculated. That is, the coupling loss Lc indicates the radiation efficiency of the electromagnetic wave from LCX1. On the contrary, when receiving, it becomes receiving efficiency and the numerical value is the same.

  FIG. 7 is a graph showing the coupling loss of the leaky coaxial cable device according to the present invention.

  The LCX 1 used here is designed so that the coupling loss is 75 dB. As shown in FIG. 7, although the coupling loss Lc has a fluctuation of about 10 dB in width, the average value is 75 dB, and it was found that LCX1 functions without any problem. Further, there was no adverse effect such as shielding by Case 2.

  FIG. 8 is a perspective view showing another example of a case constituting the leaky coaxial cable device according to the present invention. Case 2 shown in FIG. 8A is a circular (annular) case. Case 2 shown in FIG. 8B is a rectangular annular case. Case 2 shown in FIG. 8C is a corrugated case.

  Next, the experiment was conducted with the LCX 1 housed in the case 2 of various shapes. When the communication environment is, for example, a conference room having a circular table, a circular (annular) case is suitable as shown in FIG. In addition, when the table is wide, in order to provide a communication environment on both sides of the table, as shown in (b) and (c) of FIG. It was suitable.

  Such a case 2 can be manufactured by extrusion molding of a synthetic resin material, that is, a mold manufacturing method.

  FIG. 9 is a perspective view showing still another example of a case constituting the leaky coaxial cable device according to the present invention. A case 2 shown in FIG. 9A is obtained by firmly fixing the lid 2b and the main body 2a with an adhesive. A case 2 shown in FIG. 9B is obtained by fixing the lid portion 2b and the main body portion 2a with a general screw or a special screw.

  In order to firmly fix the main body 2a and the lid 2b in order to prevent the LCX 1 from being scratched or mischievous, as shown in FIG. What is necessary is just to fix 2a and the cover part 2b with an adhesive agent. Further, as shown in FIG. 9B, the main body 2a and the lid 2b may be fixed with a special screw 11 such as a two-hole screw, a triwing screw, or a one-side screw.

  8 (a), (b), (c), various cases shown in (a), (b) in FIG. 9 accommodates the same LCX1 as described above to constitute a leaky coaxial cable device. Then, when the measurement was performed using the experimental system shown in FIG. 6, a coupling loss of 75 dB was obtained as designed, and it was confirmed that there was no problem.

  FIG. 10 is a perspective view showing a configuration (connector connection type) in which a connector is provided in a case constituting the leaky coaxial cable device according to the present invention.

  In the configuration described above, the connection of the LCX 1 to the communication device is performed using the lead cable 3 attached to the incident side of the LCX 1, but the connection connector 12 is attached to the case 2 as shown in FIG. May be. The connection connector 12 is electrically connected to the LCX 1 inside the case 2 via an internal connection cable 13 attached to one end of the LCX 1. Further, the LCX 1 may be directly connected to the connection connector.

  In this way, there is no cable drawn from the case 2 housing the LCX 1 and it is easy to carry. Connection to an external communication device can be performed with a separately prepared coaxial cable with a connector at both ends.

  The present invention is applied to a leaky coaxial cable device, and in particular, to a leaky coaxial cable device including a leaky coaxial cable stored in a specific method.

1 Slot 2 Center conductor 3 Insulator 4 Outer conductor 5 Outer sheath (sheath)

Claims (6)

A center conductor, an insulator covering the center conductor, and an outer conductor covering the outside of the insulator are coaxially structured, and a plurality of slot portions for forming a leakage electromagnetic field are formed in the outer conductor, and the outer conductor A leaky coaxial cable whose conductor is covered with a jacket;
A leaky coaxial cable device, comprising: a movable case that houses the leaky coaxial cable. The leaky coaxial cable device according to claim 1, wherein the case is a cylindrical body having a linear shape or a curved shape. The leaky coaxial cable device according to claim 1, wherein the case is a cylindrical body in which a linear portion and a curved portion are continuous. The leaky coaxial cable device according to any one of claims 1 to 3, wherein the case is made of a dielectric. The leaky coaxial cable device according to any one of claims 1 to 4, wherein a lead cable for connecting to an external communication device is connected to one end of the leaky coaxial cable. The case has a connector for connection to the outside at one end,
5. The connection connector according to claim 1, wherein the connection connector is a connection cable attached to one end of the leaky coaxial cable, or is directly electrically connected to the leaky coaxial cable. The leaky coaxial cable device according to 1.

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