JPH04150422A - Distributor with antenna function - Google Patents

Abstract

PURPOSE:To improve the workability of a distributor with antenna function and functions of various kinds of mobile object communication systems by integrally forming the distribution circuit section, antenna section, and cable holding section of the distributor and laying a coaxial cable by holding the cable from its peripheral surface. CONSTITUTION:When a conducting body 31 is screwed in a coaxial cable 40 through its peripheral surface from the opened section of a box body 24 by using a nut driver, a metallic conductor 21a reaches the inner conductor 41 of the cable 40. Then, after a connecting pin 32 is inserted into a connector hole 31c and the pin 32 is electrically connected with a variable capacitor 27, a lid section 26 is closed and the installing work of this distributor is completed. A high-frequency current transmitted through the cable 40 in such a condition is supplied to an antenna 29 through the capacitor 27 and radiated from the antenna 29 as electromagnetic waves. Therefore, the installing work becomes easier and the loss given to the high-frequency signal level in the coaxial cable 40 can be minimized.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is useful when extracting signals from a coaxial cable installed inside a building, emitting electromagnetic waves, and transmitting information to a wireless terminal. This invention relates to a distributor with an antenna function.

[Summary of the Invention] The distributor with antenna function of the present invention is attached to a coaxial cable installed in a building etc. so as to be gripped from the cable circumferential surface at a desired position, and also has a distribution circuit section and an antenna section. comprising a radiating device section that radiates the supplied signal as an electromagnetic wave, and further includes first and second conductive means that contact the center conductor and outer conductor of the gripped coaxial cable and electrically couple with the distribution circuit section. By configuring the coaxial cable, it is possible to improve the functionality of a communication system using coaxial cables and simplify installation.

[Conventional technology]

In recent years, specific areas such as campuses, underground malls, tunnels,
Alternatively, when transmitting information to portable terminals or fixed terminal equipment (cordless telephones, ink horns, wireless OA equipment, etc.) inside buildings, it is considered to use wireless methods that use electromagnetic waves as a medium. .

FIG. 7 shows an example of a wireless system in which telephone information sent from an outside line is transmitted to multiple terminal devices (slave devices) that move within a building. The signal is subjected to time-division modulation or frequency modulation in the main device (master station) 2, and then sent to the coaxial cable 4 via the connection device 3. The signal supplied to this coaxial cable 4 is extracted by a distributor 5 at a predetermined location and is supplied to a transmitting device 6 equipped with an antenna A.

Then, electromagnetic waves are emitted from this antenna A into the building,
Information sent from the master station 2 is transmitted to each slave unit 7, 7, . . . .

For a mobile radio system in which signals are extracted from a coaxial cable by such a distributor 5, as shown in FIG. The electromagnetic waves emitted from the leaky coaxial cable or open coaxial cable 4a in which a slit or a spiral slit is formed are transmitted to each slave unit 7.
．． A wireless system is also known in which 7... receive signals.

[Problems to be Solved by the Invention] However, in the mobile radio system shown in FIG. Therefore, for example, it is possible to place the distributor 5 and the transmitter 6 at a desired location in a building, but the installation work is very large-scale work and construction is not easy. There is a problem in that it requires space. In addition, since the distribution ratio by the distributor 5 is usually fixed at 1:1, 3 dB
In addition to causing some degree of insertion loss, it is also difficult to control the amount of electromagnetic radiation emitted, and depending on the directivity of the antenna and the structure of the building, the radio waves may become weak and communication may not be possible.

Furthermore, as shown in FIG. 8, in the case of a system in which information is transmitted and radio waves are emitted at the same time using a leaky coaxial cable or an open coaxial cable 4A, the apparatus is simplified, but
Since electromagnetic waves are continuously radiated along the leaky coaxial cable 4A, the radiation loss is large and the transmission loss of the cable increases. Therefore, there is a problem that the information transmission distance is short (in order to transmit the signal over a long distance, many relay amplifiers 7 are required at each predetermined interval).

[Means for Solving the Problems 1] In view of these problems, the present invention provides a distributor with an antenna function suitable for a communication system using coaxial cables. As shown in the figure, the distributor with antenna function 10 is gripped from the circumferential surface at a desired position of the device, which is composed of a distribution circuit section 11 and an antenna section 12 that radiates the signal supplied from the distribution circuit section 11. the cable holding part 13 that can hold the central conductor 41 of the coaxial cable 4o held
The first conductive means 14 electrically connects the center conductor 41 and the distribution circuit section 1l by contacting only the outer conductor 43 (braided) of the gripped coaxial cable 4o, and the outer conductor 43 (braided) of the held coaxial cable 4o 43 and a second conduction means 15 for electrically connecting the distribution circuit section 11.

Further, in the distribution circuit section 11, signals are extracted using a capacitor coupling method, and the distribution ratio of the extracted signal can be continuously varied using a variable capacitor ll'a.

Further, the first conduction means includes a sharp conduction portion 14a that is inserted from the circumferential surface of the coaxial cable 40 and comes into contact with the center conductor;
A resin insulation part 1 that insulates the sharp conductive part 14a and the external conductor.
4b.

[Function] By installing the distributor 10 with an antenna function so as to grip the peripheral surface of the coaxial cable 40 at a desired position, the coaxial cable 40 can be cut to connect the distributor 10 with an antenna function. There is no need to perform any plugging process, and since the antenna function distributor 10 has the antenna 12 and directly transmits the signal extracted from the coaxial cable 40 as electromagnetic waves, no separate equipment is required. Furthermore, a capacitor coupling method is adopted to minimize the transmission loss of the coaxial cable 40 due to the connection of the antenna function divider 10, and the variable capacitor ll
If the amount of coupling is controlled using a, the amount of radiation of electromagnetic waves can be controlled.

[Embodiment 1] Fig. 2 is a perspective view showing an embodiment of the distributor with antenna function of the present invention attached to a coaxial cable 40, and an example of the internal structure of this embodiment is shown in Fig. 3. .

Note that the coaxial cable 40 has a center conductor 41 formed in the center portion, and an insulator (
A polyethylene resin) 42 is provided, and an outer conductor (braid) 43 is formed on the outer periphery of the outer conductor 42 to form a pair with the center conductor 41 to form a coaxial cable. 44 indicates a cable jacket.

In FIGS. 2 and 3, 20 indicates a distributor with an antenna function according to the present embodiment, 21 is a cable holding portion formed of, for example, synthetic resin and has a U-shaped cross section, and 22 is an open portion of the cable holding portion 21. It is a lid part that opens and closes. The cable holding part 21 and the cover part 22 are fixed with bolts 23, and a cable holding space S through which the coaxial cable 40 can pass is formed inside.

24 is a housing formed of a metal material, and screws 2
5, the holding space S is opened and closed by attaching or removing the lid portion 26.

27 is a variable capacitor forming a distribution circuit using a capacitor coupling method; 28 is a connector (BNC);
9 indicates an antenna inserted into the connector 28. In addition,
The connecting portion of the connector 28 and the housing 24 are insulated.

Reference numeral 30 designates a conductive piece that has a sharp needle shape and is molded integrally with the housing 24, and its tip portion is connected to the coaxial cable 40 from the circumferential surface when the coaxial cable 40 is installed in the holding space S. It is inserted so as to reach the outer conductor 43.

31 is a conductor formed into a bolt shape, and as shown in FIG. 4, it is a metal conductor 31a made of steel with a sharp center portion, and the tip portion is left around the metal conductor 31a. is covered with a synthetic resin layer 31b,
The outer peripheral surface of the synthetic resin layer 31b is formed into a screw groove.

Further, a connector hole 31c is formed at the center of the hexagonal portion that is electrically connected to the metal conductor 31a, so that when the connection pin 32 is inserted, the connection pin 32 is electrically connected to the metal conductor 31a. is being done. This conductor 31
When the coaxial cable 40 is installed in the holding space S, by being screwed into the screw hole 33, the tip is inserted into the coaxial cable 40 from the circumferential surface, and the metal conductor 31a part is connected to the internal conductor 41. In this state, the center conductor 41 of the coaxial cable 40 and the variable capacitor 27 are electrically connected via the conductor 31 and the lead wire 34.

Note that at this time, the metal conductor 31 is
is insulated from the outer conductor 43.

35 is an adjustment hole of the variable capacitor 27.

The antenna function distributor 20 of this embodiment is constructed as described above, and as shown in FIG.
5(a), first remove the cover 22 and fit the coaxial cable 40 into the holding space S of the cable holding part 21 from the open part. Then, as shown in FIG. 5(b), when the lid part 22 is fixed with the port 23, the conductive pieces 30 and 30 are connected to the coaxial cable 4.
0 peripheral surface, and the tip part is the coaxial cable 40
reaches the outer conductor 43 of.

Next, when the conductor 31 is screwed from the circumferential surface of the coaxial cable 40 using a nut driver from the open part of the housing 24,
As described above, the metal conductor 31a reaches the inner conductor 41. Then, after inserting the connecting pin 32 into the connector hole 31c and completing the electrical connection between the connecting pin 32 and the variable capacitor 27, (2) close the lid 26 to complete the installation work.

In this state, the information transmitted by the coaxial cable 40, that is, the high frequency current, is supplied to the antenna 29 via the variable capacitor 27, and is radiated from the antenna 29 as electromagnetic waves.
Mobile communication for slave devices around the installation location is realized.

Note that the variable capacitor 27 is adjusted using a driver or the like through the adjustment hole 35 of the variable capacitor depending on the electric field strength required at the installation location.

In this way, the antenna function distributor 20 of this embodiment does not require cutting the coaxial cable 40 and performing plugging process when it is attached to the coaxial cable 40, and is lightweight and compact. Since there is no need to install the antenna function separately, the work becomes very easy, and it is not difficult to newly attach the antenna function-equipped distributor 20 to the coaxial cable 40 that has already been laid.

In addition, since the transmission information of the coaxial cable 40 is picked up by the capacitor force by the variable capacitor 27 and the twining method, the loss imparted to the high frequency signal level in the coaxial cable 40 is minimized by connecting the distributor 20 with antenna function. be able to.

Furthermore, since the amount of electromagnetic wave radiation can be controlled by adjusting the amount of coupling of the variable capacitor 27, it is possible to obtain radio waves with the required electric field strength at the required installation location, which has the great advantage of being applicable to various communication systems. arise. For example, when the coaxial cable 40 is connected to a transmitting device and the coaxial cable 40 is laid over a long distance, if the distributor with antenna function 20 is attached to the coaxial cable 40 at a position close to the transmitting device, the variable capacitor 27 If you set the amount of coupling to a low level and make adjustments such as setting the amount of coupling to a large amount if the device is installed at a location that is far from the transmitting device and has a large amount of attenuation of the transmitted signal, the electric field strength will remain almost constant at any location. Further, it is also possible to increase the electrical anisotropy strength only in the antenna function-equipped distributor 20 in the area where the communication condition is likely to deteriorate.

FIG. 6 shows another embodiment of the present invention, in which a variable capacitor 27 is connected to a matching transformer 36, and the secondary side of the matching transformer 36 is connected to connectors 37a and 37b.
It is connected to a balanced antenna 38 (dipole antenna) via.

In addition, in the case of this embodiment, as in the above embodiment (FIG. 2), the connecting portions of the connectors 37a and 37b are connected to the housing 24.
The outer conductor 43 of the coaxial cable 40 is electrically connected to the outer conductor 43 of the coaxial cable 40 by connecting the primary side of the matching transformer 36 to the housing 24 with a lead wire. This embodiment also provides various effects similar to those of the above embodiment.

Further, the variable capacitor 27 and the conductor 31 may be connected via a limiting resistor.

〔Effect of the invention] As explained above, the distributor with antenna function of the present invention has a distribution circuit section, an antenna section, and a cable protection section.

The holding part is integrally formed, and the coaxial cable is held and attached from the circumference, which has the effect of significantly improving workability.Furthermore, the amount of coupling is controlled by a variable capacitor to reduce the electromagnetic waves radiated from the antenna. Since the electric field strength can be adjusted, the optimum electric field strength can be set depending on the installation location, making it very suitable for use in various mobile communication systems. Furthermore, since it is a capacitor coupling method, there is an advantage that the loss imparted to the transmission signal of the main coaxial cable can be minimized by attaching a distributor with an antenna function.

[Brief Description of the Drawings] Fig. 1 is a conceptual diagram of a distributor with an antenna function of the present invention, Fig. 2 is a perspective view of an embodiment of the distributor with an antenna function of the present invention attached to a coaxial cable, Fig. 3 is an explanatory diagram of the internal structure of this embodiment, Fig. 4 is a partial cross-sectional perspective view of the conductor of this embodiment, and Figs. 5 (a) and (b) are installation of this embodiment to a coaxial cable. Fig. 6 is an explanatory diagram of the internal structure of another embodiment of the distributor with antenna function of the present invention, Fig. 7 is an explanatory diagram of a conventional communication system using coaxial cables, and Fig. 8 is an explanatory diagram of the conventional communication system using coaxial cables. FIG. 1 is an explanatory diagram of a conventional communication system using an open coaxial cable. 10.20 is a distributor with antenna function, 11 is a distribution circuit section, 12.29 is an antenna, 13 is a cable holding section, 14
1 is a first conduction means, 15 is a second conduction means, 21 is a cable holder, 22 is a lid, 24 is a housing, 26 is a lid, 2
7 is a variable capacitor 28 is a connector, 30 is a conductive piece, 3
1 is a conductor 32 is a connection bin, 36 is a matching transformer, 37a, 37b are connectors, 38 is a balanced antenna,
40 is a coaxial cable, 41 is a center conductor, and 43 is an outer conductor.

Claims (4)

[Claims] (1) a radiating device section formed from a distribution circuit section and an antenna section that radiates a signal output from the distribution circuit section;
a cable holding part that can be attached to grip the coaxial cable from the circumferential surface at a desired position; and a cable holding part that contacts only the center conductor of the coaxial cable held by the cable holding means, and connects the center conductor and the distribution circuit part. a first conduction means that electrically connects; and a second conduction means that contacts only the outer conductor of the coaxial cable held by the cable holding means and electrically connects the outer conductor and the distribution circuit section. A distributor with an antenna function, characterized by comprising: (2) The distributor with an antenna function according to claim 1, wherein the distribution circuit section is configured so that a signal is extracted by a capacitor coupling method. (3) The distributor with an antenna function according to claim 1, wherein in the distribution circuit section, the distribution ratio of the extracted signal can be continuously varied. (4) The first conductive means is composed of a sharp conductive part that is inserted from the circumferential surface of the cable and comes into contact with the central conductor, and a resin insulating part that insulates the sharp conductive part and the outer conductor. A distributor with an antenna function according to claim 1, characterized in that: