JP2017005294A - Composite cable and radio communication system - Google Patents

Abstract

To provide a composite cable capable of reducing the time and cost of laying work when laying a communication cable and a leaky coaxial cable at the same time. A composite cable 1 in which a communication cable 2 and a leaky coaxial cable 3 are integrated, and the communication cable 2 and the leaky coaxial cable 3 are integrally covered with a common sheath 4 in a state of being parallel to each other. The sheath 4 includes a first covering portion 4a covering the communication cable 2 side, a second covering portion 4b covering the leaky coaxial cable 3 side, a first covering portion 4a and a second covering portion. And a plurality of slots 11 of the leaky coaxial cable 3 are open in a direction different from the direction toward the communication cable 2. [Selection] Figure 2

Description

  The present invention relates to a composite cable and a wireless communication system.

  A leaky coaxial cable (LCX: Leaky Coaxial Cable) is a cable type antenna in which a hole called a slot is provided in an outer conductor of a coaxial cable. In LCX, electromagnetic waves inside the cable can be radiated (transmitted) to the outside of the cable and electromagnetic waves outside the cable can be taken into (received) inside the cable through such a slot.

  For this reason, LCX is particularly effective for use in an environment where the communication environment is long and there are many obstacles such as metal bodies. For example, an electromagnetic wave insensitive zone is likely to occur in a winding tunnel or a place where many metal objects exist. In such a place, when a general transceiver with an antenna is used, a large number of transceivers must be installed.

  On the other hand, when LCX is used, a large number of slots periodically arranged in the extending direction of LCX function as antennas. In this case, a large number of antennas are arranged in the extending direction of LCX. Thereby, it is possible to suppress the generation of an insensitive zone of electromagnetic waves in an environment in which many obstacles such as a long and slender metal body are present by simply installing one LCX. Also, the LCX installation work can be carried out very easily because it is only necessary to route the LCX as compared with the above-described general installation of a transceiver with an antenna.

  By the way, with the recent widespread use of wireless LAN (Local Area Network), there are increasing opportunities to use LCX as an antenna for a wireless LAN access point (AP). However, there are various wireless LAN communication areas requested by customers, and it is often the case that not all areas can be covered by only one wireless LAN system in which one LCX is connected to one AP.

  In this case, a plurality of wireless LAN systems will be introduced. However, at construction sites such as tunnels and buildings, the wiring environment of the wireless LAN is not sufficiently prepared, and the work of laying the LAN cable to the AP installation position is performed. Is required. For this reason, at the construction site, work for laying the LAN cable and LCX at the same time must be performed, which not only makes the work complicated, but also increases the cost accordingly.

  Furthermore, recently, LAN cables and LCXs are laid side by side in a form that penetrates multiple floors at a building construction site or the like. At this time, if the LCX slot and the LAN cable are installed facing each other, there is a problem that the electromagnetic wave radiated from the LCX slot is blocked by the LAN cable. Therefore, when laying the LAN cable and the LCX side by side, care must be taken so that the LAN cable does not overlap the slot side of the LCX. Therefore, also in this case, the work for laying the LAN cable and the LCX becomes complicated.

JP 2001-250426 A

  One aspect of the present invention has been proposed in view of such conventional circumstances, and can reduce the time and cost of laying work when laying a communication cable and a leaky coaxial cable simultaneously, In addition, the communication cable does not affect the antenna performance of the leaky coaxial cable, and the composite cable excellent in connectivity of the communication cable and the leaky coaxial cable to the access point, and a radio communication system using such a composite cable The purpose is to provide.

  In order to achieve the above object, a composite cable according to one aspect of the present invention is a composite cable in which a communication cable and a leaky coaxial cable are integrated, and the communication cable and the leaky coaxial cable are mutually connected. The sheath has a structure integrally covered with a common sheath in a parallel state, and the sheath includes a first covering portion covering the communication cable side, and a second covering portion covering the leaky coaxial cable side. The leaky coaxial cable includes a linear center conductor, an insulator covering the center conductor, and the insulating member, the connecting portion connecting the first covering portion and the second covering portion. An outer conductor provided with a plurality of slots periodically opened in the extending direction and covering the body, the second covering portion has a structure covering the outer conductor, The plurality of slots are Characterized in that it opens toward the direction different from the direction toward the communication cable.

  In the composite cable, it is preferable that the plurality of slots are open in a direction opposite to a direction toward the communication cable.

  In the composite cable, it is preferable that a slit for notching a part of the connecting portion is provided on both sides in the extending direction of the sheath.

  In the composite cable, it is preferable that the sheath can tear the connecting portion from the slit in the extending direction.

  In the composite cable, it is preferable that the thickness of the connecting portion is smaller than the thickness of the first covering portion and the second covering portion.

  In the composite cable, it is preferable that one end side of the communication cable is longer than one end side of the leaky coaxial cable.

  In the composite cable, it is preferable that the other end side of the leaky coaxial cable is longer than the other end side of the communication cable.

  In the composite cable, a connector is attached to both ends of the communication cable, a connector is attached to one end of the leaky coaxial cable, and a termination resistor is attached to the other end of the leaky coaxial cable. Preferably it is.

  In the composite cable, it is preferable that a traction portion is provided on the other end side of the leaky coaxial cable.

  Further, in the composite cable, the communication cable has a plurality of twisted wires obtained by twisting a pair of core wires whose conductors are covered with an insulator, and the first covering portion is a bundle of the plurality of twisted wires. The LAN cable is preferably coated with

  A wireless communication system according to one aspect of the present invention includes any one of the composite cables, and an access point connected to one end side of the communication cable and one end side of the leaky coaxial cable. To do.

  The wireless communication system preferably includes an access point connected to the other end of the communication cable.

  As described above, according to one aspect of the present invention, it is possible to reduce the time and cost of laying work when laying a communication cable and a leaky coaxial cable at the same time, and the communication cable is a leaky coaxial cable. It is possible to provide a composite cable excellent in connectivity of a communication cable and a leaky coaxial cable to an access point and a wireless communication system using such a composite cable.

It is a top view which shows the structure of the composite cable which concerns on one Embodiment of this invention, and a radio | wireless communications system. It is sectional drawing of the composite cable by line segment X-X 'shown in FIG. It is a perspective view which shows the structure of LCX. It is a top view which shows the example of the connection form of LCX and AP. It is a schematic diagram which shows an example of the usage pattern of the radio | wireless communications system shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for the sake of convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent. In addition, the materials, dimensions, and the like exemplified in the following description are examples, and the present invention is not necessarily limited thereto, and can be appropriately changed and implemented without departing from the scope of the invention. .

(Composite cable)
First, a composite cable 1 shown in FIGS. 1 and 2 will be described as an embodiment of the present invention. FIG. 1 is a plan view showing the configuration of the composite cable 1. FIG. 2 is a cross-sectional view of the composite cable 1 taken along line XX ′ shown in FIG.

  As shown in FIGS. 1 and 2, the composite cable 1 is a cable in which a LAN cable 2 that is a communication cable and a leaky coaxial cable (hereinafter referred to as LCX) 3 that is a cable-type antenna are integrated. The LAN cable 2 and the LCX 3 have a structure in which the LAN cable 2 and the LCX 3 are integrally covered with a common sheath 4 in a parallel state.

  Specifically, the sheath 4 includes a first covering portion 4a covering the LAN cable 2 side, a second covering portion 4b covering the LCX3 side, a first covering portion 4a, and a second covering portion 4b. And a connecting portion 4c for connecting the two. The sheath 4 is made of polyethylene, vinyl chloride, flame retardant polyethylene, or the like in order to prevent damage to the LAN cable 2 and the LCX 3.

  The LAN cable 2 has a plurality of twisted wires 7 obtained by twisting a pair of core wires 7a and 7b in which the conductor 5 is covered with an insulator 6, and a plurality of first covering portions 4a (four in this embodiment). It has the structure which coat | covered the bundle | flux of the twisted wire 7 of this. In addition, a cross member 8 is provided at the center of the LAN cable 2 so as to partition the pair of twisted wires 7. Further, a shielding material may be provided in order to suppress the influence of electromagnetic noise. As the shielding material, for example, a metal shield such as a metal tape or a metal braid can be used.

  For the LAN cable 2 used in the present embodiment, for example, LAN cables of Category 5, Category 6, Category 6A, Category 7 conforming to ANSI / TIA / EIA-568, ISO / IEC 11801, or JIS X 5150, etc. Can be mentioned. In the category 7 LAN cable, the above-described shielding material is essential.

  2 and 3, the LCX 3 includes a linear center conductor 9, an insulator 10 concentrically covering the center conductor 9, a concentric cover of the insulator 10, and a period in the extending direction. A plurality of slots 11 arranged side by side have an outer conductor 12 provided to be open, and the second covering portion 4b has a structure in which the outer conductor 12 is concentrically covered. FIG. 3 is a perspective view showing the configuration of the LCX 3.

  For the center conductor 9 and the outer conductor 12, copper having a low electrical resistance is often used in order to keep transmission loss low, but aluminum, silver, or the like may be used. The insulator 10 is made of polyethylene having a low dielectric loss (tan δ) for the purpose of reducing transmission loss in a high frequency band. Alternatively, in order to reduce tan δ, foamable polyethylene containing fine bubbles may be used. Further, the heat-resistant LCX 3 has a structure (not shown) in which a glass fiber tape is wound around the insulator 10 so that the center conductor 9 and the outer conductor 12 do not immediately short-circuit even if burned. It may be adopted.

  The plurality of slots 11 are arranged in a straight line at a constant pitch P in the extending direction of the LCX 3 and open to the same direction. The shape of the slot 11 is not particularly limited, and may be, for example, a round hole or a long hole. In the present embodiment, as the zigzag slot 11, long holes that are oblique with respect to the extending direction are arranged side by side while alternately changing the oblique directions. Further, the vertical slot 11 may have a configuration (not shown) in which long holes perpendicular to the extending direction are arranged side by side.

  In the composite cable 1 of the present embodiment, the plurality of slots 11 of the LCX 3 are opened in a direction different from the direction toward the LAN cable 2. More specifically, the plurality of slots 11 are open in a direction opposite to the direction toward the LAN cable 2. Thereby, in the composite cable 1 of this embodiment, since the LAN cable 2 does not overlap the slot 11 side of the LCX 3, the electromagnetic waves transmitted and received through the slot 11 are not blocked by the LAN cable 2, and the antenna performance of the LCX 3 is improved. It is possible to prevent the cable 2 from having an adverse effect.

  In general LCX, the position of the slot cannot be confirmed by the sheath covering the outer conductor. On the other hand, in the composite cable 1 of the present embodiment, the position of the slot 11 covered with the second covering portion 4b can be recognized from the positional relationship between the LAN cable 2 and the LCX 3.

  As shown in FIG. 1, connectors 13 a and 13 b for connecting to a LAN terminal of an access point (hereinafter referred to as AP) 50 are attached to both ends of the LAN cable 2. On the other hand, a connector 14 for connecting to the antenna terminal of the AP 50 is attached to one end of the LCX 3. A termination resistor 15 is attached to the other end of the LCX 3. The AP 50 is electrically connected to an upper line (not shown) of the wireless LAN.

  In the composite cable 1, slits 16 in which a part of the connecting portion 4 c is cut out are provided on both sides in the extending direction of the sheath 4 in order to easily attach the connectors 13 a, 13 b, 14 and the terminal resistor 15. The sheath 4 can separate the LAN cable 2 and the LCX 3 by tearing the connecting portion 4c from the slit 16 in the extending direction. Moreover, it is preferable that the thickness of the connection part 4c of the sheath 4 is smaller than the thickness of the 1st coating | coated part 4a and the thickness of the 2nd coating | coated part 4b. This not only facilitates tearing of the connecting portion 4c between the LAN cable 2 and the LCX 3, but also prevents the first covering portion 4a from being simultaneously torn when the connecting portion 4c is torn.

  On the other end side of the LCX 3, a traction portion 17 for towing the composite cable 1 can be provided in the laying operation of the composite cable 1 described later. The traction portion 17 is composed of a traction rope 17a attached to the other end side of the LCX 3, and the other end side of the LCX 3 is pulled by the traction rope 17a. In addition, about the pulling part 17, it is not necessarily limited to such a structure, What is necessary is just a structure which can pull the composite cable 1. FIG. Moreover, the tow | pulling part 17 is not necessarily an essential structure, and can also be abbreviate | omitted as needed.

  Here, at one end of the composite cable 1, it is preferable that one end side of the LAN cable 2 is longer than one end side of the LCX 3. In this case, since the LAN cable 2 has a lower bending rigidity than the LCX 3 and can be bent easily, the connection with the AP 50 is facilitated by making one end side of the LAN cable 2 longer.

  On the other hand, since the LCX 3 has higher bending rigidity than the LAN cable 2 and is difficult to bend, the LCX 3 is connected to one end side of the LCX 3 and the AP 50 via a connection cable 51 having lower bending rigidity (easily bendable) than the LCX 3. That's fine. Note that the connection cable 51 is not necessarily indispensable, and may be omitted if one end of the LCX 3 can be directly connected to the AP 50.

  On the other hand, at the other end of the composite cable 1, the other end side of the LCX 3 is preferably longer than the other end side of the LAN cable 2. In this case, when the other end side of the LCX 3 is pulled by the pulling portion 17 (the pulling rope 17a), the LAN cable 2 does not get in the way, and the laying operation of the composite cable 1 becomes easy.

  Further, the composite cable 1 may be configured such that the other end side of the LAN cable 2 is fixed to the LCX 3 using the band 52 in the region where the slit 16 is provided, as necessary. When the other end side of the LAN cable 2 is connected to another AP 50, the other end side of the LAN cable 2 is made longer than the other end side of the LCX 3, so that the AP 50 is similar to the one end side of the LAN cable 2. Can be easily connected.

(Wireless communication system)
Next, a radio communication system 100 using the composite cable 1 will be described.
As shown in FIG. 1, the wireless communication system 100 includes the above-described composite cable 1 and an AP 50. In the wireless communication system 100, the LAN cable 2 constituting the composite cable 1 connects two APs 50 (only one AP 50 is shown in FIG. 1). The LCX 3 constituting the composite cable 1 functions as an antenna for the AP 50 by being connected to the AP 50.

  The connection form between the LCX 3 and the AP 50 is defined by ARIB STD-T33, ARIB STD-T66, ARIB STD-T71, etc. in the ARIB standard. Moreover, as a connection form of LCX3 and AP50, the connection form shown to Fig.4 (a)-(c) can be illustrated. 4A to 4C are plan views showing examples of connection forms between the LCX 3 and the AP 50. FIG.

  Specifically, the connection form shown in FIG. 4A is a “single configuration” in which one LCX 3 is connected to one AP 50. On the other hand, the connection form shown in FIG. 4B is a “branch configuration” in which a plurality of (two in this embodiment) LCXs 3 are connected to one AP 50 via a distributor 53. On the other hand, the connection form shown in FIG. 4C is a “grading configuration” in which a plurality of LCXs 3 are connected in series to one AP 50.

  Here, if a configuration in which LCX 3 is connected to one AP 50 is defined as one system, the communication area covered by one AP depends on the length of LCX 3. The length of LCX3 is limited by the transmission loss of LCX3. That is, when the transmission loss of LCX3 is large, the usable limit length of LCX3 is shortened. Conversely, when the transmission loss of LCX3 is small, the usable limit length of LCX3 becomes long. Therefore, the system length in the radio communication system 100 is limited by the characteristics of the LCX3.

  For example, in the wireless communication system 100 having a single configuration, when the LCX3 is 5D (the number before D indicates the approximate inner diameter [unit: mm] of the outer conductor 12), the system length is about 30 m and 10D size. The system length in the case is about 80 m, and the system length in the case of the 20D size is about 180 m. On the other hand, in the wireless communication system 100 of the branch configuration, the system length when the LCX 3 is 5D size is about 50 m, the system length when the 10D size is about 140 m, and the system length when the 20D size is about 250 m.

  Next, the laying operation of the composite cable 1 will be described with reference to FIG. FIG. 5 is a schematic diagram illustrating an example of a usage pattern of the wireless communication system 100.

  In the present embodiment, as shown in FIG. 5, in the construction site of the high-rise building 200, the wireless communication system 100 is configured by laying the composite cable 1 in the height direction through a through hole 201 that passes between the floors. Can be built.

  On the lower floor of the high-rise building 200, one end of the composite cable 1 is connected to the upper line via the AP 50 and the network hub 54. On the other hand, the other end of the composite cable 1 is connected to another composite cable 1 via an AP 50 and a network hub 54. Another composite cable 1 is extended and laid to the upper floor of the high-rise building 200.

  In the laying operation of the composite cable 1, since the LAN cable 2 and the LCX 3 are integrated, the LAN cable 2 and the LCX 3 can be laid simultaneously. Moreover, the composite cable 1 which penetrated the through-hole 201 by the said pulling part 17 can be pulled up from a lower floor to an upper floor easily and safely.

  Thereby, it is possible to reduce the time and cost of laying work. Moreover, when the LAN cable 2 and the LCX 3 are locked and fixed, the LAN cable 2 and the LCX 3 can both be locked and fixed at once by locking and fixing the composite cable 1.

  In the composite cable 1, since the position of the slot 11 in the LCX 3 is located on the opposite side of the LAN cable 2, the LAN cable 2 does not overlap the slot 11 side of the LCX 3 during laying. For this reason, it is possible to prevent the LAN cable 2 from adversely affecting the antenna performance of the LCX 3 after laying.

  Further, since the position of the slot 11 can be recognized from the positional relationship between the LAN cable 2 and the LCX 3, for example, the composite cable 1 can be laid by recognizing the position of the slot 11 even in the dark of the construction site. Furthermore, the composite cable 1 can be laid while paying attention not to shield the slot 11 of the LCX 3 by a radio wave shield such as metal.

  Further, in the laying operation of the composite cable 1, for example, when laying in an environment where a plurality of LAN cables are routed, the LAN cable 2 to be connected to the AP 50 is traced by tracing the LAN cable 2 from the end of the LCX 3. Can be found. Thereby, it is possible to prevent a connection error of the LAN cable 2 to the AP 50.

  In the composite cable 1, since the LAN cable 2 and the LCX 3 are integrally covered with the common sheath 4, the LAN cable 2 and the LCX 3 can have the same color. As a result, the composite cable 1 is less likely to impair the aesthetics of the laid portion as an apparently single cable.

In addition, this invention is not necessarily limited to the thing of the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, the composite cable 1 has a configuration in which the LAN cable 2 is used as a communication cable, but various other communication cables can be used. For example, examples of communication cables other than the LAN cable 2 include an optical cable and a coaxial cable. When these communication cables are connected to the AP 50, they cannot be directly connected to the AP 50. Therefore, after conversion to the LAN cable 2 using a media converter or the like, it is possible to connect to the AP 50.

  Further, in the wireless communication system 100, a plurality of APs 50 can be connected by the composite cable 1, but the antenna connected to the AP 50 located at the end is an antenna other than the composite cable 1, For example, a single LCX 3 can be connected.

  DESCRIPTION OF SYMBOLS 1 ... Composite cable 2 ... LAN cable (communication cable) 3 ... Leaky coaxial cable (LCX) 4 ... Sheath 4a ... 1st coating | coated part 4b ... 2nd coating | coated part 4c ... Connection part 5 ... Conductor 6 ... Insulator 7a, 7b ... core wire 7 ... twisted wire 8 ... cross member 9 ... center conductor 10 ... insulator 11 ... slot 12 ... external conductors 13a, 13b ... connector 14 ... connector 15 ... termination resistor 16 ... slit 17 ... traction part 50 ... access Point (AP) 51 ... Connection cable 52 ... Band 53 ... Distributor 54 ... Network hub 100 ... Wireless communication system

Claims (12)

A composite cable that integrates a communication cable and a leaky coaxial cable,
The communication cable and the leaky coaxial cable have a structure integrally covered with a common sheath in a state of being parallel to each other,
The sheath connects the first covering portion covering the communication cable side, the second covering portion covering the leaky coaxial cable side, and the first covering portion and the second covering portion. A connecting portion,
The leaky coaxial cable includes a linear center conductor, an insulator that covers the center conductor, an outer conductor that covers the insulator and has a plurality of slots that are periodically arranged in the extending direction. And the second covering portion has a structure covering the outer conductor,
The composite cable, wherein the plurality of slots are open in a direction different from a direction toward the communication cable.   The composite cable according to claim 1, wherein the plurality of slots are open in a direction opposite to a direction toward the communication cable.   3. The composite cable according to claim 1, wherein a slit that cuts out a part of the connecting portion is provided on both sides in the extending direction of the sheath.   The composite cable according to claim 3, wherein the sheath is capable of tearing the connecting portion in an extending direction from the slit.   The composite cable according to claim 4, wherein a thickness of the connecting portion is smaller than a thickness of the first covering portion.   The composite cable according to claim 1, wherein one end side of the communication cable is longer than one end side of the leaky coaxial cable.   The composite cable according to claim 1, wherein the other end side of the leaky coaxial cable is longer than the other end side of the communication cable. Connectors are attached to both ends of the communication cable,
The composite according to any one of claims 1 to 7, wherein a connector is attached to one end of the leaky coaxial cable, and a termination resistor is attached to the other end of the leaky coaxial cable. cable.   The composite cable according to claim 1, wherein a pulling portion is provided on the other end side of the leaky coaxial cable.   The communication cable is a LAN cable having a plurality of twisted wires obtained by twisting a pair of core wires whose conductors are covered with an insulator, and the first covering portion covering a bundle of the plurality of twisted wires. The composite cable according to any one of claims 1 to 9, wherein: The composite cable according to any one of claims 1 to 10,
A wireless communication system comprising: an access point connected to one end side of the communication cable and one end side of the leaky coaxial cable.   The wireless communication system according to claim 11, further comprising an access point connected to the other end of the communication cable.

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