JPH0352017Y2 - - Google Patents

Description

[Detailed explanation of the invention] (Field of industrial application) This invention relates to a free-standing antenna iron pole for radio transmission, and is a site-saving type suitable for constructing an antenna with a height of about 45 m on a particularly narrow site. , and the structure of an economical antenna column.

(Prior Art and Problems) Most conventional antenna iron poles for radio transmission have been of the branch line type in which a transmission antenna pole 2 (steel pole) is supported by a branch line 11, as shown in FIG. A major reason for this was that the construction cost of branch-type steel poles was low. However, constructing a branch-type steel pole approximately 45m in height requires a site of approximately ^3,000m2 , which is difficult to acquire these days and is also expensive, and when land costs are included, the overall cost rises significantly.

In addition, in areas where existing radio relay stations are becoming urbanized, there are frequent disputes with landowners regarding the use of land under unpurchased branch lines, which causes maintenance problems. Many of them are also difficult to access.

Therefore, in order to solve the above-mentioned problems, there is a strong need for the development of an economical, self-supporting, base-insulated transmitting antenna pole that does not require a large amount of land.

In general, radio transmitting antennas use the steel pole itself as an antenna, so if half the wavelength of the transmitting radio waves is used, the height of the antenna will be over 100 meters. However, the output is small
A 100W class transmitting antenna pole is currently transmitting the above radio waves at a height of about 45 to 65 meters. The object of this invention is to replace such a transmitting antenna pole with one that saves space.

Similar to the above-mentioned base-insulated self-supporting antenna, there is a small-scale ship transmitting antenna pole 21 (6 to 7 m in this case) as shown in FIG. It is impossible to support a transmitting antenna pole as long as 45 m with the structure shown, which is attached through the antenna, due to the structure of the antenna pole support and the strength of the insulator.

In addition, as a free-standing type, there has been a conventional
There is also a method of using a free-standing steel tower or a branch-type steel pole as an antenna support, as shown in Figure 6b, or a method of insulating and supporting the base of a free-standing steel tower with an insulator and supplying power to the tower body. The structure shown in Fig. 6a requires a large site, and the structure shown in Fig. 6b requires a high construction cost, and neither of them can be said to be space-saving or economical.

(Means for Solving the Problems) The present invention focuses on the above-mentioned problems and, as mentioned earlier, develops an economical self-supporting base-insulated transmitting antenna pole that does not require a large site. The purpose is to

In other words, the self-supporting antenna of the present invention has at least three upright support columns arranged on a basic structure installed on the ground surface so as to be located on the circumference of a circle drawn on the surface of the basic structure. , insert the end of a conductor column forming the radiator of the antenna into the center of the one circle drawn by at least three of the upright support columns so that the conductor column stands upright; An insulator is interposed between the upright support column and between the conductor column and the foundation structure, and the dead weight, bending moment, and shear force from the conductor column are mainly converted into compressive force on the insulator. The present invention is characterized in that the conductor column is configured to support the conductor column upright.

(Example) The present invention will now be described in detail by way of example with reference to the accompanying drawings.

FIG. 1 shows a basic configuration diagram of the first and second embodiments of the free-standing antenna according to the present invention. Figure 1 a, b
are an elevation view and a plan view of the first embodiment, Figures 1c and d
These are an elevation view and a plan view of the second embodiment.

This self-supporting base-insulated transmitting antenna column consists of a reinforced concrete foundation structure 1, a steel pipe conductor column 2 (with a crown 3), and a plurality of reinforced concrete upright support columns that support the conductor column 2 (antenna column). 4
and insulators 5, 6, and 7 of the insulating support insulator. The number of upright support columns 4 made of reinforced concrete is three to four or more depending on the scale of the antenna column 2, and the antenna column 2 is inserted into the upright support column 4 and supported by insulators 5, 6, and 7 (insulating support insulators). do. The support structure of the antenna column 2 by the insulating support insulators 5, 6, and 7 is designed to mainly convert the dead weight, bending moment, and shear force from the antenna column into compressive force.

As shown in Fig. 2, this structure is determined by the height of the antenna column 2, and in the first embodiment, which is about 45 m, one bell-shaped insulating support insulator 7 for supporting vertical reaction force is installed at the lower support point. , four bell-shaped insulating support insulators 6 for horizontal reaction force and four bell-shaped insulating support insulators 5 for horizontal reaction force at the upper support point are arranged as shown in FIG.

FIG. 3 shows the direction of current when power is fed from the base to the conductor column of the antenna pole 2 according to the present invention using a coaxial line as a feed line. If the four upright support columns 4 arranged on the circumference as shown in Fig. 2 are the outer conductors of a coaxial line, when power is supplied from the transmitter 8 via the feeder line 9, the outer conductors are inserted into the center. A current i flows in the same direction as the conductor column 2. Therefore, the radiation from the portion where the conductor column is hidden by the upright support column is compensated for by the current flowing outside the support column, so there is no drop in radiated power.

In order to more fully consider the pillars arranged on the circumference as the outer conductor of the coaxial line, we need to
The wire mesh 10 may be arranged around the outer circumference including the four support columns as shown in FIG.

In this invention, since the signal current in the medium wave band is fed to the 1/4 wavelength antenna, the direction of the signal current due to the current distribution is as shown in Figure 3, and the portion of the upright support column 4 is also Therefore, there is no decrease in radiation efficiency due to the provision of upright support columns.

(Effects of the invention) By implementing this invention, it is possible to realize an antenna for a low-output radio relay broadcasting station that does not require branch lines. As a result, it can be constructed on a smaller site than in the case of constructing a conventional self-standing antenna that requires branch lines, and its construction cost is also economical. Furthermore, the radiation efficiency is less likely to be lowered.

[Brief explanation of the drawing]

Figure 1 is a basic configuration diagram of the first and second embodiments of the free-standing antenna according to the present invention, and Figures a and b are
Figures c and d are elevational views and plan views of the second embodiment, and Figure 2 is a cross section showing the antenna column support structure of the first embodiment of the present invention. Figure a, longitudinal cross-sectional view b, and Figure 3 are diagrams schematically showing the antenna pole according to the present invention when power is fed by a coaxial line as a feed line, and Figure 4 is an elevational view of a conventional branch line type transmitting antenna pole. Figure a, plan view b, and figure 5 are diagrams showing a small-scale antenna pole for ships, which is an example of a conventional site layout, and figures 6 a and b each use a free-standing steel tower as a support for the antenna. , is a diagram showing a conventional example in which a base insulated freestanding steel tower is used as an antenna. 1... Foundation structure, 2, 21... Conductor column (transmission antenna column), 3... Top crown, 4... Upright support column, 5,
6, 7... Insulator (insulation support insulator), 8... Transmitter, 9... Power line, 10... Wire mesh, 11... Branch line, 12... Branch line insulator, 13... Branch line anchor, 14... ... Base insulating stand insulator, 15 ... Broadcasting equipment building, 16 ... Minimum land area, 22 ... Antenna support insulator, 23 ... Hull wall, 31 ... Line antenna, 32 ... Self-supporting steel tower, 33 ... ...Base insulated freestanding steel tower, 34...Base insulated structure.

Claims (1)

[Claims for Utility Model Registration] 1. At least three upright support columns are arranged on a foundation structure installed on the ground surface so as to be located on the circumference of a circle drawn on the surface of the foundation structure. death,
Insert the end of a conductor column constituting the radiator of the antenna into the center of the one circle drawn by at least three upright support columns so that the conductor column stands upright, and connect the conductor column and the A structure in which an insulator is inserted between the upright support column and between the conductor column and the foundation structure, and the dead weight, bending moment, and shear force from the conductor column are mainly converted into compressive force on the insulator. A free-standing antenna characterized in that the conductor column is supported upright. 2. In the free-standing antenna according to claim 1, which supplies radiant power from the base of the conductor column via a feeder line, the outer circumference includes the upright support column arranged on the circumference. A free-standing antenna characterized by having a wire mesh placed inside.