JPH11118856A - Antenna raising and lowering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the reflection and interference of the electromagnetic wave, to easily measure a high place, and to easily change a height of an antenna by making a total supporting body for movably supporting an antenna, mainly out of a foamed resin material, moving the antenna along the supporting body, and stopping the same at a desired position. SOLUTION: A cylindrical supporting body 103 is mounted on a table 110, and an antenna raising and lowering hole 104 is formed coaxially with a central axix, so that an antenna 101 for measuring the intensity of electric field, can be raised and lowered in the raising and lowering hole 104. The antenna supporting body 103 is made of a foamed resin material such as a foamed styrol plastic or the like of less than 2 of dielectric constant εγ. Whereby the reflection and interference of the electromagnetic wave are reduced, and the measurement can be performed without disordering the distribution of the electric field of the electromagnetic wave 115 radiated from a wave source of an electronic equipment to be measured 116 or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a configuration of an antenna elevating device for elevating and lowering an antenna used for measuring electric field strength and the like.

[0002]

2. Description of the Related Art With the spread of portable telephones, computers, and the like, radiated electromagnetic waves generated from electronic devices have become a serious problem. In recent years, electromagnetic waves radiated from electronic devices have been actively measured. Since the magnitude of the electromagnetic wave is represented by the strength of the electric field intensity, the magnitude of the electromagnetic wave radiated from the electronic device can be known as the reception electric field strength of an antenna installed at a distance from the electronic device. The electric field intensity of electromagnetic waves radiated from electronic devices changes depending on the distance and height from the wave source.To measure the magnitude of the radiated electromagnetic waves, the height of the receiving antenna installed at a certain distance from the wave source must be measured. Change the field strength.

[0003] The electric field strength measurement with the receiving antenna raised and lowered is also performed when evaluating the characteristics of an anechoic chamber. The characteristics of the anechoic chamber are evaluated by radiating electromagnetic waves from the transmitting antenna and measuring the electric field strength by changing the height of the receiving antenna installed at a location separated by a certain distance, and comparing it with the characteristics of an open site without walls.

In order to perform the above-mentioned electric field strength measurement, it is necessary to change the height of the receiving antenna in any case. That is, the antenna used in an anechoic chamber or open site needs to have a structure that allows the receiving antenna to be freely moved up and down for measurement. Therefore, a conventional receiving antenna used in an anechoic chamber or open site is attached to a vertically movable antenna elevating device, which is configured to freely change the height and measure the electric field intensity.

[0005] The plane of polarization of electromagnetic waves radiated from a wave source such as electronic equipment is not constant, and often vertical polarization and horizontal polarization are mixed. For this reason, the antenna elevating device often has a mechanism for mechanically switching the plane of polarization received by the antenna so that both the planes of vertical and horizontal polarization can be measured.

An example of such a conventional antenna elevating device is a "elevating and lowering of measurement antenna and polarization plane switching driving device".
Is described in Japanese Utility Model Publication No. 3-6013.

FIG. 12 is a perspective view of this known conventional antenna elevating device.

As shown in FIG. 1, a main pole 1203 erected on a base 1210 has a receiving antenna 1
An elevating table 1202 that can switch the polarization plane of 201 and can move up and down along the main pole 1203 is provided. Pulleys 1205 and 1213 are provided at the upper and lower ends of the main pole 1203. The antenna lifting drive belt 1209 is connected to these pulleys 1205 and 12
13 and both ends thereof are lifted
It is fixed to 2. The electric motor in the drive unit 1212 is directly connected to the lower pulley 1213,
213 is driven to rotate to raise and lower the drive belt 12.
09 is driven to move the antenna 1201 and the elevator 1202 up and down.

When it is desired to switch the reception polarization plane of the antenna 1201, the power of the electric motor is applied to the polarization plane switching belt 1217 by a switching device provided in the drive unit 1212 to switch the polarization plane of the antenna 1201.

However, as described above, the antenna 120
The configuration for mechanically switching the plane of polarization cannot be easily created due to its complicated structure, cannot simultaneously receive electromagnetic waves of different planes of polarization, and takes time to switch the plane of polarization, so measurement is required. It takes a long time.

As described above, the measured electronic device 1216
Since the electric field intensity of the electromagnetic wave 1215 radiated from such a wave source changes depending on the position and height of the receiving antenna, it is necessary to change the antenna height for measurement. That is, at the time of measurement, the receiving antenna 1201 is frequently moved up and down.

An antenna 1 is provided at the tip of the elevator 1202.
Since the main pole 201 is attached, the main pole 1203 and the elevating platform 1202 need to have strength enough to withstand the load (moment) of the antenna 1201.

Therefore, the main pole 1203 and the elevator 1202 used in the antenna elevating device are made of a non-metallic material that can withstand frequent antenna elevating and antenna load (moment) and have a high mechanical strength and a reinforced plastic material. Or made of wood.

However, when the main pole 1203 and the elevator 1202 made of a reinforced plastic material are used, since the relative dielectric constant is about ε _r > 5, reflection and interference of electromagnetic waves at the main pole 1203 and the elevator 1202 are performed. Is large, which causes disturbance of the electric field distribution near the antenna 1201. In particular, when measuring the electric field strength with a dipole antenna with a wide directivity, the disturbed electric field distribution behind the receiving antenna is directly measured, so
You cannot get accurate results. In addition, when the main pole 1203 and the elevating table 1202 made of wood are used,
Due to the change in humidity at the measurement site, the amount of water in the wood changes, and the relative dielectric constant changes. When the relative permittivity of the main pole 1203 or the lift 1202 near the antenna 1201 changes, the amount of reflection and interference of electromagnetic waves change with the change of humidity, so that not only the electromagnetic field distribution near the antenna 1201 is disturbed but also the measurement result You lose reproducibility.

Further, if the main pole 1203 made of reinforced plastic or wood made of a heavy and hard material falls down, the surrounding wall surface is greatly damaged. In particular, in a radio wave anechoic chamber, the surrounding wall is made of a styrene foam or a radio wave absorber made of a urethane material having a low mechanical strength. Therefore, when the main pole 1203 falls down, the wall is greatly damaged.

Therefore, the height of the antenna can be freely adjusted, the device itself does not reflect the electromagnetic wave from the wave source, and even if it falls down, the damage to the surrounding wall can be minimized. There is a need for the development of an antenna elevating device that can be used.

[0017]

Problems to be solved by the conventional antenna elevating device are as follows. (A) When the main pole and the lifting platform are made of a reinforced plastic material, the relative permittivity is about ε _r > 5, so that the reflection and interference of the electromagnetic wave at the main pole and the lifting platform cause a large disturbance of the electric field distribution. . (B) When the main pole and the lifting platform are made of wood, the moisture content in the pillar changes depending on the humidity at the place of use. When the moisture content of the wood changes, the relative dielectric constant changes, so that the reflection and interference of the electromagnetic waves at the main pole and the lift stand change. That is,
The reproducibility of the measured values cannot be obtained due to the environment of the measuring field. Further, as in the case of the reinforced plastic, the reflection and interference of the electromagnetic wave are large, which causes disturbance of the electric field distribution. (C) If the main pole made of a reinforced plastic material or a wooden body falls, the surrounding walls and the like are seriously damaged. In particular, damage is increased on a wall having low mechanical strength such as an anechoic chamber. (D) Since the polarization plane is switched mechanically, the structure is complicated and cannot be easily formed. Not only cannot electromagnetic waves of different polarization planes be received at the same time, but also measurement time is required because the polarization planes need to be switched.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an antenna in which reflection and interference of electromagnetic waves by an antenna support and an antenna lift are small and the electric field distribution in the vicinity of the antenna is not disturbed. An object of the present invention is to provide a lifting device.

[0019]

According to the present invention, there is provided a support means which extends in a vertical direction of an antenna and supports the antenna so as to be able to move up and down, the support means being entirely formed of a foamed resin material. There is provided an antenna lifting / lowering device comprising: a driving means connected to the antenna, capable of moving the antenna along the supporting means and stopping at a desired position.

As described above, according to the present invention, since the supporting means located near the antenna is formed substantially entirely of a foamed resin material (normally, a relative dielectric constant: ε _r <2), the supporting means Reflection and interference of the electromagnetic wave at this close portion are reduced, and the measurement can be performed without disturbing the electric field distribution of the electromagnetic wave radiated from the wave source. In addition, even when the device falls down, the device is made of a light and soft foam resin material, so that damage to surrounding walls can be minimized when the device falls down, which is very safe.

Preferably, the driving means is directly connected to the antenna.

The apparatus further includes an antenna case formed of a foamed resin material for containing the antenna, wherein the driving means is connected to the antenna case, moves the antenna case along the support means, and moves the antenna case to a desired position. It is also preferable to be able to stop at. According to this arrangement, the foamed resin material to the support means and the antenna case both existing near the antenna (relative dielectric constant: ε _r <2) so used, the reflection and interference of electromagnetic waves in this region emitted from small wave source Measurement can be performed without disturbing the electric field distribution of the electromagnetic wave. In addition, since the antenna is covered with the antenna case, the antenna can be smoothly moved up and down without being caught inside the antenna elevating hole.

In this case, it is preferable that the antenna case is configured so as to be able to include a multi-axis antenna. Thus, orthogonal electric field components such as horizontal polarization and vertical polarization (all three-dimensional electric field components in three axes) can be measured simultaneously. By simultaneously measuring a plurality of electric field components, it is not necessary to incorporate a polarization plane switching mechanism into the antenna elevating device, and the structure of the antenna can be simplified.
Further, since it is not necessary to switch the polarization plane, the measurement time can be reduced.

The driving means includes a lifting rope having one end connected to the antenna or the antenna case, and an electric motor connected to the other end of the lifting rope for taking in and sending out the lifting rope. Is also preferred. The height of the antenna can be freely determined by controlling the electric motor with a computer or a programmable controller because the antenna moves up and down by rotation of an electric motor provided in the driving means.

It is also preferred that the driving means includes a pulley fixed to the upper part of the supporting means and guiding the lifting rope.

The supporting means is a cylindrical support having an antenna elevating hole at the center, and the antenna moves up and down the antenna elevating hole coaxial with the central axis of the cylindrical support, so that the symmetry is good, and Since the load is evenly applied to the entire antenna elevating device, even if it is made of a foamed resin material having low mechanical strength, there is no breakage. If the load of the antenna is evenly applied to the entire antenna elevating device, the shape of the support need not be cylindrical, but may be a U-shaped or U-shaped groove, such as a groove having a U-shaped cross section. An antenna elevating groove in which the antenna elevates and lowers may be provided in parallel, and the antenna may be raised and lowered at the center of the support. In addition, with such a structure having the elevating hole or the elevating groove, when the antenna is moved up and down, no lateral force is applied to the antenna elevating cylinder, so that there is no danger of falling.

It is also preferable that the supporting means has a guide mechanism for maintaining the direction of the antenna in the horizontal plane in a desired direction.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an antenna elevating device according to the present invention will be described in detail based on embodiments.

FIG. 1 is a perspective view for explaining one embodiment of the antenna elevating device of the present invention, and FIG.
It is sectional drawing which shows X 'cross section.

As shown in these figures, a cylindrical support (antenna elevating cylinder) 103 is provided on a base 110, and an antenna elevating hole 104 is coaxial with the center axis of the antenna elevating cylinder 103. Is formed. For example, an antenna 101 composed of a short dipole antenna for measuring the electric field strength can be freely moved up and down in the antenna elevating hole 104.

The antenna elevating cylinder 103 in which the antenna 101 is provided is made of a foamed resin material such as styrene foam having a relative dielectric constant of ε _r <2. The antenna elevating cylinder 103 in the present embodiment is 1 m × 1 m as the first stage.
× 4m, 0.75mx0.75mx2m as the second stage,
As a third stage, styrofoam columns of 0.5 mx 0.5 mx 1.5 m are stacked in the longitudinal direction, and are adhered and fixed to each other with an adhesive or a double-sided adhesive tape. Also,
When the styrofoam columns are fitted with each other, the strength at the time of stacking is further increased.

An antenna elevating hole 104 having a diameter of about 0.3 m is cut out at the center of the antenna elevating cylinder 103 so that the antenna 101 can elevate and descend along the longitudinal direction.

As described above, according to the present embodiment, the antenna elevating cylinder 103 which constitutes most of the antenna elevating device and is disposed near the antenna 101 has a relative dielectric constant of ε _r.
<2> Since it is formed of a foamed resin material such as styrene foam, the reflection and interference of electromagnetic waves are extremely small, and the electromagnetic waves 115 radiated from a wave source such as the electronic device 116 to be measured.
Can be measured without disturbing the electric field distribution.

In this embodiment, in order to facilitate processing and assembling, the antenna elevating cylinder 10 is formed by stacking styrofoam prisms of different sizes.
Although 3 is formed, as long as the mechanical strength is high and the production is easy, it may be formed in a shape such as a cylinder, a prism, or a polygonal prism. In the present embodiment, the antenna elevating hole 10 is used.
4 is formed by cutting out a prismatic styrofoam constituting the antenna elevating cylinder 103, but if it is difficult to form the antenna elevating cylinder 103, the antenna elevating hole 104 is formed in the center by attaching a plate-like styrofoam to form a wall. An existing antenna elevating cylinder 103 may be formed. Further, the shape of the antenna elevating hole 104 is cylindrical in the present embodiment, but may be rectangular or polygonal.

The antenna 101 is directly connected to one end of an antenna elevating rope 109.
The other end of 09 is wound around a driving pulley 113 provided in the driving unit 112. Antenna elevating rope 10
Reference numeral 9 denotes a pulley 113 which passes through two upper pulleys 105 rotatably fixed to a top plate 106 provided at the upper end of the antenna elevating cylinder 103 and a lower pulley 114 rotatably mounted on a base 110. I have. The pulley 113 is configured to be rotationally driven by an electric motor (not shown) in the drive unit 112. The pulley 113 takes in or sends out the antenna elevating rope 109 in response to the rotation of the electric motor, whereby the antenna 101 freely moves up and down in the antenna elevating hole 104 and stops at a desired position.

FIG. 3 is a diagram for explaining the control of the electric motor in the drive section 112. As shown in FIG.
By controlling the electric motor 302 in the drive unit 112 by 1, the amount of winding of the lifting rope 109 can be controlled, whereby the antenna 101 can be raised and lowered and stopped at a desired position.

FIG. 4 shows the top plate 106 shown in FIGS.
FIG. 3 is a diagram showing the configuration of a part in detail. As shown in the figure, the top plate 106 is provided with holes 106a and 106b, and the two upper pulleys 105
And 106b are rotatably mounted respectively. The shafts of these upper pulleys 105 are fixed to the top plate 106 with screws made of a nonmetallic material such as polycarbonate screws so that reflection and interference of electromagnetic waves do not occur.

The top plate 106 is formed of a fluororesin material having a relative permittivity of ε _r <3 so as not to disturb the electric field distribution of the electromagnetic wave from the wave source. Also, two upper pulleys 105
Also, a resin material is used for the axes so as not to disturb the electric field distribution around the axes. The material of the top plate 106 is not limited to fluorocarbon resin, but a material having a relative dielectric constant of ε _r <3 is used so that the electric field distribution near the antenna is not disturbed by reflection and interference of electromagnetic waves on the top plate 106. It is desirable.

If the strength of the top plate 106 alone is insufficient, the relative dielectric constant of styrofoam or the like below the top plate is ε _r <3.
A reinforcing plate made of a material such as

FIG. 5 is a diagram showing in detail the structure of the portion of the antenna 101 disposed in the antenna elevating hole 104 of the antenna elevating cylinder 103. In the figure, reference numeral 107 denotes a guide rope fixed in the antenna elevating hole 104, and reference numeral 108 denotes a guide guided by the guide rope 107, which is attached to the antenna 101.
The guide rope 107 and the guide 108 correspond to the guide mechanism of the present invention, and are for maintaining the direction of the antenna 101 in a horizontal plane in a desired direction.

In general, when the antenna 101 is moved up and down, the direction of the antenna 101 in the horizontal plane may change due to twisting of the antenna elevating rope 109 or the like. If the directional relationship between the antenna 101 and the polarization plane is different in this way, the received electric field intensity will change. Therefore, in the present invention, such a guide mechanism is provided so that the directional relationship between the antenna 101 and the polarization plane is always kept constant irrespective of the elevation of the antenna, and stable electric field intensity measurement is performed.

In this embodiment, the two guide ropes 10
7 is provided, but by increasing the number of guide ropes 107 to three or four, the antenna 1
The directional relationship between 01 and the polarization plane can be more reliably kept constant. Since the guide 108 has a small shape relative to the apparatus, there is almost no electrical influence on the measurement, but it is desirable to form the guide 108 from a resin material having a relative dielectric constant of ε _r <5 in order to further reduce the influence. Similarly, since the guide rope 107 is thin with respect to the device, there is almost no electrical influence on the measurement.
In order to further reduce the influence, it is desirable to use a rope made of a material having a relative dielectric constant of ε _r <5. Further, in the present embodiment, the guide 108 is directly attached to the antenna 101 and the guide rope 107 is passed through. However, a hole may be formed in the antenna 101 itself and the guide rope 107 may be passed. It is preferable to reduce the friction between the guide 108 and the guide rope 107 so that the antenna 101 can move up and down smoothly.

A caster 111 is attached to the base 110 so that the antenna elevating device can be easily moved.

The type of the antenna 101 installed in the antenna elevating device is not limited to the short dipole antenna. However, the size of the antenna elevating device becomes very large depending on the size of the antenna 101, so that the antenna 101 is as small as possible. It is preferable to choose an antenna. Also,
It is also possible to use orthogonal two-axis or orthogonal three-axis short dipole antennas. With an orthogonal biaxial antenna, orthogonal two-dimensional electric field components such as vertical polarization and horizontal polarization can be measured simultaneously, and there is no need to switch the polarization plane. , Measurement time can be shortened. In the case of an orthogonal three-axis antenna, all electric field components existing in three dimensions can be measured at the same time, and simultaneous measurement of three-dimensional electric field components which was impossible with a conventional antenna elevating device can be performed without switching the polarization plane. , The structure of the antenna elevating device is simplified,
Measurement time can be shortened.

Although the antennas shown in FIGS. 1 and 2 are horizontal antennas for measuring horizontal polarization, vertical polarization can be measured if the antennas are arranged vertically.

Since the antenna 101 moves up and down in the antenna elevating hole 104 which is coaxial with the central axis of the antenna elevating cylinder 103, the symmetry is good, and the load of the antenna 101 is evenly applied to the entire antenna elevating device, so that the device has low mechanical strength. Even if it is made of weak Styrofoam, it will not be damaged. Further, when the antenna is moved up and down, no lateral force is applied to the antenna elevating cylinder 103, so that there is no danger of falling down.

Also, since most of the antenna lifting and lowering device is made of light and soft styrofoam, even if it falls down, damage to the surrounding wall surface can be minimized, which is very safe.

FIG. 6 is a perspective view for explaining another embodiment of the antenna elevating device of the present invention, and FIG.
It is sectional drawing which shows the -Y 'cross section.

As shown in these figures, a cylindrical support (antenna elevating cylinder) 603 is provided on a base 610, and an antenna elevating hole 604 is coaxial with the center axis of the antenna elevating cylinder 603. Is formed. For example, an antenna case 602 having a built-in short dipole antenna 601 (FIGS. 8 and 9) for measuring the electric field strength is configured to be able to freely move up and down inside the antenna elevating hole 604.

The antenna elevating cylinder 603 in which the antenna case 602 is provided is made of a foamed resin material such as styrene foam having a relative dielectric constant of ε _r <2. The antenna elevating cylinder 603 in the present embodiment is 1 m as the first stage.
× 1m × 4m, second stage 0.75m × 0.75m ×
Styrene foam columns of 0.5 m × 0.5 m × 1.5 m as the second and third stages are stacked in the longitudinal direction, and are fixed to each other with an adhesive or a double-sided adhesive tape.
Further, when the styrofoam columns are provided with a fitting, the strength at the time of stacking is further increased.

At the center of the antenna elevating cylinder 603, an antenna elevating hole 604 having a diameter of about 0.3 m is cut out so that the antenna case 602 can elevate and descend along the longitudinal direction.

As described above, according to the present embodiment, most of the antenna elevating device is constituted and the antenna case 602 is formed.
Therefore, since the antenna elevating cylinder 603 disposed near the antenna 601 is formed of a foamed resin material such as styrene foam having a relative dielectric constant of ε _r <2, the reflection and interference of electromagnetic waves are very small, and Measurement can be performed without disturbing the electric field distribution of the electromagnetic wave 615 emitted from a wave source such as the electronic device 616.

In this embodiment, the antenna elevating cylinder 60 is formed by stacking styrofoam prisms of different sizes so as to facilitate processing and assembly.
Although 3 is formed, as long as the mechanical strength is high and the production is easy, it may be formed in a shape such as a cylinder, a prism, or a polygonal prism. In this embodiment, the antenna elevating hole 60 is used.
4 is formed by cutting out a prismatic styrofoam constituting the antenna elevating cylinder 603, but if it is difficult to form the antenna elevating cylinder 603, the antenna elevating hole 604 is formed in the center by attaching a plate-shaped styrofoam to the wall to form a wall. An existing antenna elevating cylinder 603 may be formed. Furthermore, the shape of the antenna elevating hole 604 is cylindrical in the present embodiment, but may be rectangular or polygonal.

An antenna case 602 having a built-in antenna 601 is directly connected to one end of an antenna elevating rope 609, and the other end of the rope 609 is connected to a driving pulley 613 provided in a driving unit 612. It is wound. The antenna elevating rope 609 passes through two upper pulleys 605 rotatably fixed to a top plate 606 provided at the upper end of the antenna elevating cylinder 603 and a lower pulley 614 rotatably attached to a base 610. The pulley 613 has been reached. The pulley 613 is configured to be driven to rotate by an electric motor (not shown) in the drive unit 612. The pulley 613 takes in or sends out the rope 609 for elevating and lowering the antenna according to the rotation of the electric motor.
Rises and falls freely in the antenna elevating hole 604 and stops at a desired position.

Also in this embodiment, the amount of winding of the elevating rope 609 can be controlled by controlling the electric motor in the driving unit 612 by a personal computer or a programmable controller, thereby moving the antenna case 602 up and down. Thus, it can be stopped at a desired position.

The top plate 606 is provided with holes similar to the holes 106a and 106b shown in FIG. 4 in the above-described embodiment, and two upper pulleys 605 are rotatably mounted in these holes, respectively. . These upper pulleys 60
The axis 5 is made of a non-metallic screw such as a polycarbonate screw to prevent electromagnetic wave reflection and interference from occurring.
6 fixed.

The top plate 606 is formed of a fluororesin material having a relative permittivity of ε _r <3 so as not to disturb the electric field distribution of the electromagnetic wave from the wave source. Also, two upper pulleys 605
Also, a resin material is used for the axes so as not to disturb the electric field distribution around the axes. The material of the top plate 606 is not limited to fluorocarbon resin, but a material having a relative dielectric constant of ε _r <3 is used so as not to disturb the electric field distribution near the antenna due to reflection and interference of electromagnetic waves on the top plate 606. It is desirable.

When the strength is insufficient with only the top plate 606, the relative dielectric constant of styrene foam or the like below the top plate 606 is ε _r <3.
A reinforcing plate made of a material such as

FIG. 8 is a perspective view for explaining the antenna case 602, and FIG.
FIG. 3 is an exploded perspective view of FIG. As shown in these figures, the antenna case 602 is formed of a styrofoam cylinder having a diameter of 0.2 m × 0.4 m, and the antenna 60
1 is provided with a groove. Thus, the antenna case 602 is formed of a styrene foam material having a relative dielectric constant of ε _r <2 so as not to disturb the electric field distribution near the antenna.

The shape of the antenna case 602 is not limited to a cylinder, and may be a prism, a polygon, or a sphere. However, the antenna case 602 needs to be shaped so as not to be caught inside the antenna elevating hole 604.

In this embodiment, a short dipole antenna 601 having an antenna length of 0.15 m is provided inside an antenna case 602. This antenna 601
Is not limited to the short dipole antenna, but it is preferable to select an antenna as small as possible because the size of the antenna 601 greatly increases the size of the antenna elevating device.

8 and 9, reference numeral 607 denotes a guide rope fixed in the antenna elevating hole 604. Reference numeral 608 denotes a guide guided by the guide rope 607, which is attached to the antenna case 602. These guide rope 607 and guide 608 are
The antenna case 60 corresponds to the guide mechanism of the present invention.
2 is for maintaining the direction of the antenna 601 in the horizontal plane in a desired direction.

In general, when the antenna case 602 is moved up and down, the direction of the antenna case 602 in the horizontal plane may change due to twisting of the antenna elevating rope 609 or the like. If the directional relationship between the antenna case 602 and thus the antenna 601 and the plane of polarization is different, the intensity of the received electric field changes. Therefore, in the present invention, such a guide mechanism is provided, and the antenna case 60 is provided.
The directional relationship between 2 and the polarization plane is always kept constant irrespective of the elevation of the antenna case 602, and stable electric field intensity measurement is performed.

In this embodiment, two guide ropes 60
7 is described, but by increasing the number of guide ropes 607 to three or four, the directional relationship between the antenna case 602 and the plane of polarization can be more reliably kept constant. The guide 608 has a small shape with respect to the apparatus and thus has little electrical influence on the measurement, but is preferably formed of a resin material having a relative dielectric constant of ε _r <5 in order to further reduce the influence. Similarly, since the guide rope 607 is thin with respect to the apparatus, there is almost no electrical influence on the measurement, but in order to further reduce the influence, the relative permittivity is set to ε _r <
It is desirable to use a rope made of the material No. 5. In the present embodiment, the guide 608 is directly attached to the antenna case 602 to allow the guide rope 607 to pass through. However, a hole may be formed in the antenna case 602 itself to allow the guide rope 607 to pass therethrough. Note that it is preferable to reduce friction between the guide 608 and the guide rope 607 so that the antenna case 602 can move up and down smoothly.

A caster 611 is attached to the base 610 so that the antenna elevating device can be easily moved.

Although the antennas shown in FIGS. 6 to 9 are horizontal antennas for measuring horizontal polarization, vertical polarization can be measured if the antennas are arranged vertically.

The antenna case 602 is the antenna elevating cylinder 6
Since the antenna is moved up and down in the antenna elevating hole 604 coaxial with the central axis of the antenna 03, the symmetry is good, and the loads of the antenna case 602 and the antenna 601 are evenly applied to the entire antenna elevating device. Even if it is not damaged. Further, when the antenna case 602 moves up and down, no lateral force is applied to the antenna elevating cylinder 603, so there is no danger of falling.

Also, since most of the antenna lifting and lowering device is made of light and soft styrofoam, even if it falls down, damage to surrounding wall surfaces can be minimized, which is very safe.

FIG. 10 is a perspective view for explaining another example of the antenna case. In this example, the antenna case is configured to mount an orthogonal two-axis short dipole antenna. The other configuration except the antenna case is the same as the configuration of the embodiment of FIGS. 6 and 7.

As shown in FIG. 10, the antenna case 1002 is configured such that a two-axis antenna 1001 orthogonal to the inside is mounted inside. Antenna 100
If 1 is an orthogonal two-axis antenna, orthogonal two-dimensional electric field components such as vertical polarization and horizontal polarization can be measured simultaneously. If the antenna having this configuration is used, there is no need to switch the polarization plane, which has been conventionally required, so that the structure of the antenna lifting / lowering device is simplified, and the measurement time can be reduced.

FIG. 11 is a perspective view for explaining still another example of the antenna case. In this example, the antenna case is configured to mount an orthogonal three-axis short dipole antenna. The other configuration except the antenna case is the same as the configuration of the embodiment of FIGS. 6 and 7.

As shown in FIG. 11, the antenna case 11
Numeral 02 is configured so that a three-axis antenna 1101 orthogonal to each other is mounted inside. If the antenna 1101 is an orthogonal three-axis antenna, all electric field components existing in three dimensions can be measured simultaneously. By using an antenna having this configuration, simultaneous measurement of three-dimensional electric field components, which was impossible with a conventional antenna elevating device, can be realized without switching the polarization plane, so that the structure of the antenna elevating device is simplified, and the measurement time is reduced. Can be shortened.

In the embodiment described above, an antenna elevating cylinder having an antenna elevating hole coaxial with the central axis of the support is used as the antenna support, but an antenna substantially coaxial with the central axis of the support is used. Similar effects can be obtained by using an antenna elevating support having a U-shaped or U-shaped cross section provided with elevating grooves.

The embodiments described above all show the present invention by way of example and not by way of limitation, and the present invention can be embodied in various other modified forms and modified forms. Therefore, the scope of the present invention is defined only by the appended claims and their equivalents.

[0075]

As described above in detail, according to the present invention, the support extending in the elevating direction of the antenna and supporting the antenna so as to be able to ascend and descend is formed entirely of a foamed resin material. Means and a driving means connected to the antenna and capable of moving the antenna along the supporting means and stopping at a desired position, so that the reflection and interference of electromagnetic waves by the antenna support and the antenna lift are small. It is possible to obtain an antenna elevating device that does not disturb the electric field distribution in the vicinity and that can easily measure a high place and change the antenna height.

More specifically, by using an antenna elevating cylinder and an antenna case made of a polystyrene foam material having a relative dielectric constant of ε _r <2, the reflection and interference of electromagnetic waves are small and the electric field distribution near the antenna is disturbed. It can be measured without.

If styrofoam is used for the antenna elevating cylinder and the antenna case, the dielectric constant of the device does not change even if the humidity in the measurement field changes, and the measured values can be reproducible.

If the configuration is such that the electric motor in the drive section is controlled, the antenna height can be easily set.

Since light and soft styrofoam is used for the material of the antenna elevating cylinder, damage to the surrounding wall can be minimized even if the antenna falls down.

Since the antenna and the antenna case are configured to move up and down in a hole coaxial with the center axis of the antenna elevating cylinder, a force is applied uniformly and well, so that the device is formed of styrene foam having low mechanical strength. Even if not damaged. In addition, when the antenna and the antenna case are moved up and down, no lateral force is applied to the antenna elevating cylinder, so that there is no danger of falling.

By using the orthogonal two-axis short dipole antenna, a two-dimensional electric field distribution can be measured simultaneously. Furthermore, by using an orthogonal three-axis short dipole antenna, all three-dimensional electric field components can be measured simultaneously. In this case, since it is not necessary to switch the polarization plane of the antenna, the structure of the antenna elevating device is simplified, and the measurement time can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an embodiment of an antenna elevating device according to the present invention.

FIG. 2 is a sectional view showing a section taken along line XX ′ of FIG. 1;

FIG. 3 is a block diagram for controlling an electric motor for driving an antenna in the embodiment of FIG. 1;

FIG. 4 is a perspective view illustrating a top plate in the embodiment of FIG.

FIG. 5 is a perspective view illustrating the configuration of the antenna in the embodiment of FIG.

FIG. 6 is a perspective view for explaining another embodiment of the antenna elevating device of the present invention.

FIG. 7 is a sectional view showing a section taken along line YY ′ of FIG. 6;

FIG. 8 is a perspective view for explaining an antenna case in the embodiment of FIG. 6;

FIG. 9 is an exploded perspective view of the antenna case of FIG.

FIG. 10 is a perspective view for explaining another example of the antenna case.

FIG. 11 is a perspective view for explaining still another example of the antenna case.

FIG. 12 is a perspective view illustrating a conventional antenna elevating device.

[Explanation of symbols]

 101, 601, 1001, 1101 Antenna 602, 1002, 1102 Antenna case 103, 603 Antenna elevating cylinder 104, 604 Antenna elevating hole 105, 605 Upper pulley 106, 606 Top plate 107, 607 Guide rope 108, 608 Guide 109, 609 Antenna Elevating rope 110, 610 Base 111, 611 Caster 112, 612 Drive unit 113, 613 Pulley 114, 614 Lower pulley 115, 615 Electromagnetic wave 116, 616 Electronic device to be measured

Claims (9)

[Claims] 1. A supporting means extending along a vertical direction of an antenna and supporting the antenna so as to be able to move up and down, the whole being mainly formed of a foamed resin material, and connected to the antenna. A drive unit for moving the antenna along the support unit and stopping the antenna at a desired position. 2. The apparatus according to claim 1, wherein said driving means is directly connected to said antenna. 3. An antenna case formed of a foamed resin material for containing the antenna, further comprising:
The driving means is connected to the antenna case,
The device according to claim 1, wherein the antenna case is configured to be movable along the support means and to be stopped at a desired position. 4. The apparatus according to claim 3, wherein the antenna case is configured to include a multi-axis antenna. 5. The ascending and descending rope, one end of which is connected to the antenna or the antenna case,
The apparatus according to any one of claims 1 to 4, further comprising an electric motor connected to the other end of the lifting rope and adapted to take in and send out the lifting rope. . 6. The apparatus according to claim 5, wherein the driving means includes a pulley fixed to an upper portion of the support means and guiding the lifting rope. 7. The apparatus according to claim 1, wherein said support means is a cylindrical support having an antenna elevating hole at a central portion. 8. The support according to claim 1, wherein said support means is a support having a U-shaped or U-shaped cross-section having an antenna elevating groove at a central portion. apparatus. 9. The apparatus according to claim 1, wherein said support means has a guide mechanism for maintaining a direction of said antenna in a horizontal plane in a desired direction. Equipment.