JP2013031002A - Tower antenna, radio communication system, and tower antenna manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a leakage coaxial cable to stand straight upright without being twisted, to contribute to stable communication.SOLUTION: A tower antenna using a leakage coaxial cable includes: a leakage coaxial cable 22 having a straight line 23 drawn on an outer coat in a cable length direction; a tower cover 21 disposed to surround the leakage coaxial cable 22, for holding the leakage coaxial cable 22 upright; a first fixture 26 disposed inside the tower cover 21, for fixing the upper end of the leakage coaxial cable 22; and a second fixture 27 disposed inside the tower cover 21, for fixing the lower end of the leakage coaxial cable 22. The second fixture 27 is fixed to the tower cover 21 to correct a twist of the leakage coaxial cable 22 to make the line 23 straight, in a state of pulling the lower end of the leakage coaxial cable 22 downward.

Description

  Embodiments described herein relate generally to a tower antenna using a leaky coaxial cable. Furthermore, the present invention relates to a radio communication system using a tower antenna and a method for manufacturing the tower antenna.

  Conventionally, a wireless communication system using a leaky coaxial cable (LCX cable) is arranged such that an LCX cable connected to an antenna terminal of a wireless base station is arranged in a tunnel or factory at a length of several tens to several hundreds of meters or more. A long and narrow communicable area is created.

  On the other hand, recently, as a use in a narrow range such as a conference room or a table, a simple wireless communication system in which the length of the LCX cable is shortened has been attracting attention. For example, when an LCX cable is erected on a table in the vertical direction and used as a “tower antenna”, the communicable area can be restricted only on the table.

  However, the LCX cable used for this type of application has a longer antenna length than an ordinary monopole antenna and is difficult to handle. In particular, it is necessary to make the LCX cable provided on the table thinner due to restrictions on the installation area and the like, and it is not easy to make such a thin LCX cable self-supporting. Furthermore, in order to achieve uniform radiation from the LCX cable, it is necessary to make the LCX cable stand upright and eliminate twists, which is extremely difficult to achieve.

JP 2005-236745 A

  The problem to be solved by the invention is to provide a tower type antenna, a radio communication system, and a method for manufacturing the tower type antenna that can straighten a leaky coaxial cable without twisting and can contribute to stabilization of communication. It is.

  The tower type antenna of the embodiment is provided so as to surround the leaky coaxial cable in which a linear line along the cable length direction is drawn on the outer skin, and to surround the leaky coaxial cable, and holds the leaky coaxial cable upright. And a first fixing jig disposed in the tower cover and fixing the upper end of the leaky coaxial cable, and disposed in the tower cover and fixing the lower end of the leaky coaxial cable. A second fixing jig. The second fixing jig is fixed to the tower cover in a state where the twist of the leaky coaxial cable is corrected so that the line becomes a straight line and the lower end portion of the leaky coaxial cable is pulled downward. .

The perspective view which shows schematic structure of the radio | wireless communication apparatus concerning 1st Embodiment. The schematic diagram which shows the structure of the antenna part used for the radio | wireless communication apparatus of FIG. The perspective view which shows the structure of the coaxial connector attached to the both ends of LCX cable. Sectional drawing which shows the structure of the 1st fixing jig of the upper end side of an LCX cable. The perspective view which shows the structure of the 2nd fixing jig of the lower end side of an LCX cable. The top view which shows the structure of the 2nd fixing jig of the lower end side of an LCX cable. Sectional drawing which shows the structure of the 2nd fixing jig of the lower end side of an LCX cable.

  Hereinafter, a wireless communication system according to an embodiment will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic configuration diagram showing a wireless communication system according to the first embodiment.

  A tower type antenna 20 using an LCX cable is provided at the center of the circular table 10, and a wireless LAN access point (radio base station) 40 is connected to the antenna 20 via an approach cable 30.

  The tower type antenna 20 has an LCX cable 22 held upright in a tower cover 21 made of plastic or the like. The tower cover 21 is obtained by dividing a cylindrical body into two along the central axis, and the LCX cable 22 is sandwiched between the covers 21a and 21b.

  FIG. 2 shows a state where one cover 21 a of the tower cover 21 is removed. A straight line 23 is drawn on the outer skin of the LCX cable 22 along the cable length direction so that the twist of the cable can be recognized. A guide body 29 for suppressing the bending of the LCX cable 22 is provided in the tower cover 21.

  A coaxial connector 24 as shown in FIG. 3 is connected to one end (base end) and the other end (termination) of the LCX cable 22, respectively. The coaxial connector 24 fixes the LCX cable 22 at a hexagonal section.

  A termination resistor 25 is connected to the coaxial connector 24 on the termination side of the LCX cable 22. The coaxial connector 24 on the terminal side of the LCX cable 22 is fixed to a first fixing jig 26 installed in the tower cover 21. That is, as shown in FIG. 4, the coaxial connector 24 is fixed to the metal fittings 26a and 26b by sandwiching the hexagonal portion of the coaxial connector 24 between the two metal fittings 26a and 26b and connecting the metal fittings with screws. In this state, the fixing jig 26 is installed in the tower cover 21, so that the tip side of the LCX cable 22 is fixed.

  Although not shown in the drawing, a recess into which the first fixing jig 26 is fitted is formed in the tower cover 21, and the first fixing jig 26 is fixed to a predetermined state with the covers 21 a and 21 b being integrated. It can be fixed in position. Further, if the vertical position for fixing the first fixing jig 26 in the tower cover 21 can be changed, it is possible to cope with LCX cables having different lengths.

  The coaxial connector 24 on the proximal end side of the LCX cable 22 is sandwiched and fixed by a second fixing jig 27 as shown in FIGS. As shown in the perspective view of FIG. 5, the metal fitting forming the second fixing jig 27 has a hole 51 into which the hexagonal portion of the coaxial connector 24 is inserted, and from the ring bodies 27a and 27b divided into two. Become. A gear-shaped groove 52 along the axial direction is formed on the peripheral surfaces of the ring bodies 27a and 27b, and a taper 53 having a convex center is formed on the upper end side surfaces of the ring bodies 27a and 27b.

  As shown in FIG. 6, a groove 55 corresponding to the groove 52 on the peripheral surface of the second fixing jig 27 is formed in the lower portion of the tower cover 21. The position of the lower portion of the LCX cable 22 in the rotational direction is determined by the combination of the grooves 52 and 55.

  Further, as shown in FIG. 7, a taper 56 that matches the taper 53 of the second fixing jig 27 is formed in the lower portion of the tower cover 21. The taper 56 comes into contact with the taper 53 of the second fixing jig 27 when the tower cover 21 is integrated. As a result, when the tower cover 21 divided into two parts is integrated, the second fixing jig 27 is pulled downward.

  That is, the LCX cable 22 is twisted by positioning the groove 52 of the second fixing jig 27 in alignment with the groove 55 of the tower cover 21 while referring to the line 23 formed on the LCX cable 22. Can be prevented. Furthermore, by forming the tower cover 21 by integrating the covers 21a and 21b, the lower end portion of the LCX cable 22 is pulled downward, and a constant tension can be applied to the LCX cable 22. Thereby, it becomes possible to make the LCX cable 22 stand straight without twisting.

  The LCX cable 22 is connected to the coaxial cable connector 24 on the proximal end side after the upper end and the lower end are fixed to the tower cover 21 as described above. And it is connected to the antenna terminal etc. of the access point 40 via this approach cable 30.

  Thus, according to the present embodiment, the tower antenna 20 using the LCX cable 22 can be provided upright on the table 10. For this reason, the communicable area can be restricted only on the table 10. In this case, since the LCX cable 22 can be fixed in a straight line with a constant tension without twisting, the reliability of communication can be improved.

(Modification)
The present invention is not limited to the above-described embodiments.

  The 1st fixing jig which fixes the upper end part of an LCX cable in a tower cover is not limited to the said FIG. 4, and can be suitably changed according to a specification. Any device that can fix the upper end of the LCX cable and fix it in the tower cover 21 may be used.

  The 2nd fixing jig which fixes the lower end part of an LCX cable in a tower cover is not limited to the said FIGS. 5-7, It can change suitably according to a specification. What is necessary is just to have the mechanism which prescribes | regulates the rotation direction position of the lower end part of LCX cable, and the mechanism which pulls the lower end part of LCX cable below.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

10 ... Table 20 ... Tower type antenna 30 ... Approach cable 40 ... Access point (radio base station)
21 ... Tower cover 22 ... LCX cable 23 ... Line 24 ... Coaxial connector 25 ... Terminating resistor 26 ... First fixing jig 27 ... Second fixing jig 29 ... Guide body 51 ... Hole 52, 55 ... Groove 53, 56 ... Taper

Claims (5)

Leaky coaxial cable with a straight line drawn along the cable length direction on the outer sheath,
A tower cover provided so as to surround the leaky coaxial cable, and holding the leaky coaxial cable upright;
A first fixing jig disposed in the tower cover and fixing an upper end portion of the leaky coaxial cable;
A second fixing jig disposed in the tower cover and fixing a lower end portion of the leaky coaxial cable;
Comprising
The second fixing jig is fixed to the tower cover in a state where the twist of the leaky coaxial cable is corrected so that the line becomes a straight line and the lower end portion of the leaky coaxial cable is pulled downward. A tower antenna characterized by being a thing. The second fixing jig is provided coaxially with the leaky coaxial cable, and a gear-shaped groove is formed on a peripheral surface of a ring-shaped metal fitting for fixing the cable, and a taper is formed on the upper surface of the metal fitting. It has been
The tower cover has an inner surface formed with a groove that engages with the groove of the metal fitting of the second fixing jig, and a taper that contacts the taper of the metal fitting.
2. The tower antenna according to claim 1, wherein the twist of the leaky coaxial cable is corrected by the engagement position of each groove, and the lower end portion of the leaky coaxial cable is pulled downward by the contact of each taper.   The tower cover is obtained by dividing a cylindrical body into two along an axial direction, and the first and second fixing jigs are fitted and fixed at predetermined positions. 2. The tower type antenna according to 2. Leaky coaxial cable with a straight line drawn along the cable length direction on the outer sheath,
A tower cover provided so as to surround the leaky coaxial cable, and holding the leaky coaxial cable upright;
A first fixing jig disposed in the tower cover and fixing an upper end portion of the leaky coaxial cable;
A terminating resistor connected to the upper end of the leaky coaxial cable;
A first screw is disposed in the tower cover, corrects the twist of the leaky coaxial cable so that the line is a straight line, and fixes the lower end portion of the leaky coaxial cable with tension applied to the leaky coaxial cable. 2 fixtures,
A radio base station connected via an approach cable to the lower end of the leaky coaxial cable;
A wireless communication system comprising: A leaky coaxial cable in which a straight line along the cable length direction is drawn on the outer sheath, a tower cover provided so as to surround the leaky coaxial cable, and holding the leaky coaxial cable upright, and the tower A first fixing jig that is arranged in the cover and fixes the upper end of the leaky coaxial cable; a second fixing jig that is arranged in the tower cover and fixes the lower end of the leaky coaxial cable; A tower-type antenna manufacturing method comprising:
Fixing the upper end portion of the leaky coaxial cable in the tower cover by the first fixing jig;
Next, the second fixing jig is used to position the lower end portion of the leaky coaxial cable in the rotational direction so that the line is a straight line, and the lower end portion of the leaky coaxial cable is pulled downward. Fixing the leaky coaxial cable in the tower cover;
The manufacturing method of the tower type antenna characterized by including.

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