JPH088627A - Feeder fixing method for helical antenna - Google Patents

Abstract

PURPOSE:To provide a helical antenna which has the excellent electric characteristic and also can withstand the antenna output of large electric power. CONSTITUTION:Each fixed part of a feeder 1 is bound by a string 7 knitted by a single continuous Kevlar (R) fiber, and both ends of the string 7 are fixed by an adhesive 3 at the positions sufficiently distant from the feeder 1 and near both ends of an element 2. The position of the feeder 1 is fixed by the string 7 and the element 2. The electric field level is low and the dielectric loss is small at a position near the adhesive 3 since the adhesive 3 is hardened at a position far away from the feeder 1. Thus the electric characteristic of a helical antenna is never deteriorated and the adhesive 3 does not substantially generate the heat.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for fixing a feeder line of a helical antenna mounted on an artificial satellite, for example.

[0002]

2. Description of the Related Art A helical antenna is a kind of vertical beam antenna and radiates radio waves in the axial direction with respect to the winding axis direction of a spiral conductor. Further, it can be used at various frequencies by changing the diameter of the helix and the interval between the helices to predetermined positions depending on the frequency used.

FIG. 21 is a block diagram showing an example of a conventional helical antenna. 1 is a feed line formed by spirally winding a metal wire such as copper having a low conductor resistance in a predetermined shape.
Is GFRP (Glass Fiber Reinfor)
ced Plastics; glass fiber reinforced plastic) or KFRP (Kevlar FiberRe)
An element for fixing the power supply line 1 to a predetermined position by a cylinder of a dielectric material such as information plastics (Kevlar fiber reinforced plastic), 3 is an adhesive for fixing the power supply line 1 to the element 2, 4 is a radio wave Is a screw for joining the element 2 and the cup 4, and 6 is a connector for supplying power. L
The distance between the spirally wound power supply lines 1 and D represents the diameter of the spirally wound power supply line 1. FIG. 22 is an enlarged view of the bonding portion between the power supply line 1 and the element 2.

FIG. 23 is a block diagram showing another example of a conventional helical antenna, and FIGS. 24 and 25 are enlarged views of a fixed portion. In the figure, 1 to 6 are the same as in the above example,
Reference numeral 7 is a string for fixing the power supply line 1 to the element 2, and the knot of the string is fixed by the adhesive 3.

Generally, an antenna mounted on an artificial satellite is
At the time of launch, it is stored in the fairing of the rocket and receives acoustic and vibration loads due to the injection of the rocket engine, shaking of liquid fuel, etc., and then several shock loads due to the separation of the rocket before reaching the orbit of the satellite. receive. After that, the satellite enters the orbit, and the antenna is powered to operate the communication. During operation, loads other than minute vibration loads due to satellite attitude control are not applied,
The antenna mounted outside the satellite and exposed to outer space,
In the orbit of the satellite, the temperature will change by as much as -180 to 110 ° C. Further, before launching, various tests are performed under environmental conditions stricter than the above-mentioned space environment in order to ensure that the space environment is endured.

The helical antenna is constructed as described above, and the feed line 1 has a spiral interval L and a diameter D set to predetermined dimensions according to the frequency to be used, and within a predetermined range, for example, 2. If it is in the 5 GHz band, it maintains its position with an accuracy of about 0.5 mm to function as an antenna having a predetermined electric performance. Therefore, the helical antenna mounted on the satellite must maintain its position with the above-mentioned accuracy and must withstand the above-mentioned environmental conditions. For example, if the power supply line 1 is not fixed to the element 2,
The position of the power supply line 1 is displaced, and the power supply line 1 strikes the element 2 due to vibration, and the power supply line 1 and the element 2 are destroyed and the function of the antenna is lost. For this reason, in the conventional helical antenna, in order to fix the feed line 1 to the element 2, the adhesive is spread as shown in the example of the helical antenna of FIG. 21, or the helical antenna of FIG. As shown, the string 7 was tied up, and the string 7 was fixed with an adhesive so as not to loosen due to heat cycle, vibration, or sound.

The helical antenna is a mechanism in which an electric field is generated around the feeder line 1 when a current flows through the feeder line 1 and the electric field is radiated as a radio wave. The electric field is strongest in the vicinity of the feeder line 1 and decreases in inverse proportion to the square of the distance from the feeder line 1. In addition, when there is a dielectric around the power supply line 1, dielectric loss occurs when an electric field passes through the dielectric.
The amount of dielectric loss increases in proportion to the strength of the electric field, the dielectric loss tangent of the dielectric, and the size of the dielectric. Dielectric loss causes deterioration of electrical performance and is also converted into heat. When it is used as a receiving antenna, its input power is small, so it does not cause a big problem, but when it is used as a transmitting antenna, when the radio wave is radiated with high power, the dielectric heats up extremely and the dielectric is allowed There was a problem of exceeding the temperature. In particular, when bonding is performed, the adhesive adheres to the power supply line 1 over a wide area, so that the strongest electric field passes through the adhesive and heat generation is further increased.

[0008]

In order to solve such a problem, for example, the adhesive 3 for fixing the string 7 is made an adhesive having a low dielectric constant and a low dielectric loss tangent. There is a method of using a material with a low tangent,
As the adhesive and material, polycynate (polycy
However, in reality, it is difficult to use because it has a problem that it affects other parts at the time of curing and its availability is low because the curing temperature is high.

The present invention has been made in order to solve such a problem, and it is a helical antenna that maintains the position of the power feeding line 1 with required accuracy in terms of electrical characteristics, withstands environmental conditions such as rocket launch and has a low dielectric loss. The present invention provides a method for fixing a power supply line.

[0010]

According to the method for solidifying a feed line of a helical antenna according to the present invention, a feed tube is fixed to a dielectric cylinder for fixing the feed line with a string, and the tip of the string is sufficiently separated from the feed line. It is fixed with an adhesive at the location.

Further, according to the present invention, the feed line is fixed by a dielectric material having a low dielectric loss tangent so as to be held in the cylinder of the dielectric material.

According to the present invention, the feed line is fixed to the dielectric cylinder through a dielectric bush having a low dielectric loss tangent.

Further, according to the present invention, the feeder is fixed to the cylinder of the dielectric so as to be suspended by the string of the dielectric.

According to the present invention, the above-mentioned dielectric cylinder and the power supply line are connected by a heat-melting dielectric string, and the knot is fused by heat and fixed.

[0015]

According to the method of fixing the feed line of the helical antenna of the present invention, the adhesive having large dielectric loss is kept away from the feed line to prevent dielectric loss and heat generation of the dielectric due to dielectric loss.

Further, by fixing the power supply line with a dielectric having a low dielectric constant and a low dielectric loss tangent, heat generation of the dielectric due to dielectric loss of the parts to be fixed is prevented.

According to the present invention, the power supply line is fixed via the dielectric having a low dielectric constant and a low dielectric loss tangent, so that parts having a large dielectric loss are excluded from the periphery of the power supply line and heat generation due to the dielectric loss is prevented.

Also, by hanging the feeder line with a string,
Parts with large dielectric loss are eliminated from the periphery of the power supply line to prevent heat generation due to dielectric loss.

The present invention eliminates an adhesive having a large dielectric loss by fixing the power supply line with a heat-melting string.
Prevents heat generation due to dielectric loss.

[0020]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention.
FIG. 2 is an enlarged view showing details of the fixing portion, FIG. 3 is a cross-sectional view of the fixing portion, FIG. 4 is an enlarged view showing an example of a strap binding method for fixing, and FIG. 5 is a string adhesive fixing portion. FIG. 6 and 7 are enlarged views showing an embodiment of a strap fixing method different from that shown in FIG. In FIG. 1, 1,
2, 3, 4, 5, 6, and 7 are the same as the above-mentioned conventional devices. Each fixing portion of the power supply line 1 is connected by one continuous string 7, and both ends of the string 7 are sufficiently separated from the power supply line 1, that is, near both ends of the element 2 by the adhesive 3 to prevent the loosening. ing.

For example, if the knot on the feeder 1 is adhered, the distance from the feeder 1 to the adhesive 3 is 0 m.
The distance from m is about 0.5 mm, and the adhesive 3 can be separated from the power supply line 1 by 5 mm or more by setting it near both ends of the element 2. Here, when the distance between the adhesive 3 and the power supply line 1 changes from 0.5 mm to 5 mm, the adhesive 3
Since the dielectric loss due to is inversely proportional to the square of the distance,
It can be improved by a factor of 1.

Because of the above-mentioned structure, the position of the feeder line 1 is fixed by the string 7 and the element 2.
Also, by fixing it, it can withstand environmental conditions, and
Since the mass of the adhesive 3 is far from the power supply line 1, the electric field near the adhesive 3 is low, the dielectric loss is small, the electric performance is not deteriorated, and the heat of the adhesive 3 is almost eliminated.

Here, if the string 7 is a string knitted with Kevlar fiber, for example, the dielectric loss tangent is 0.02, which is smaller than the dielectric loss tangent 0.04 of the adhesive 3, and the volume is also bonded. Since it is sufficiently smaller than that of agent 3, there is no particular problem. Here, as for the fixing of the string 7, as shown in FIG. 6 and FIG.
The same effect can be obtained if the fixing portion formed by the adhesive 3 is separated from the power supply line 1.

Example 2. 8 is a configuration diagram showing a second embodiment of the present invention, and FIG. 9 is an enlarged view of a fixed portion of the power supply line 1. In the figure, reference numerals 1, 2, 4, 5, 6 are the same as those in the first embodiment, and 8 is a cover installed so as to sandwich the feeder line 1 between the element 2 and the cover. It can be attached by fitting.

With the above-mentioned structure, the position of the power supply line 1 is fixed by the cover 8 and the element 2, and the fixing can withstand environmental conditions, and the material of the cover 8 is made to have a dielectric loss tangent. Since a low material can be used, the dielectric loss of the fixed part of the power supply line 1 is small, the deterioration of the electrical performance is small, and the heat generation of the fixed part of the power supply line 1 is almost eliminated. Here, considering the effect of fixing the cover 8 with an adhesive, the adhesive thickness is 0.1 m.
Since it is about m and is not in close contact with the power supply line 1,
It can be said that the effect can be almost ignored.

Here, as the material of the cover 8, for example, PTFE (Polytetrara) having a low dielectric constant and a low dielectric loss tangent is used.
Fluoroethylene: Tetrafluoride ethylene resin)
And modified PPO (Polyphenylene oxide)
e: Modified polyphenylene oxide resin) and the like. These materials have a dielectric loss tangent of about 0.0002-0.
0007 and about 0.015 of GFRP and KFRP
Although smaller than 0.04, the coefficient of thermal expansion is about 50 to 1
00ppm / ° C, which is about 3-14 of GFRP and KFRP
Larger than ppm / ℃, GFRP and KFR
Molding is not easy compared to P. Therefore, the element 2 is unsuitable as a material and cannot be integrally molded with the cover 8.

Example 3. 10 is a configuration diagram showing a third embodiment of the present invention, FIG. 11 is an enlarged view of a fixing portion, and FIG. 12 is a detailed view showing assembly details of the fixing portion. In the figure,
1, 2, 4, 5, 6 are the same as those in the first embodiment, 9 is for fixing the power supply line 1 and 10 is a bush attached to the element 2 and 10 is for opening in the element 2 for fixing the bush 9 11 is an arrow indicating the assembling direction. As shown in FIG. 12, the bush 9 is attached to the hole 10 of the element 2 by bonding or fitting from the direction of the arrow 11.

Because of the above-mentioned structure, the position of the power supply line 1 is fixed by the bush 9 and the element 2, and the fixation can withstand environmental conditions, and the material of the bush 9 has a dielectric loss tangent. Since a low material can be used, the dielectric loss in the vicinity of the fixed portion of the power supply line 1 is reduced, the deterioration of the electrical performance is small, and the heat generation of the fixed portion of the power supply line 1 is almost eliminated. Comparing the case where the feeder line 1 is directly fixed to the element 2 made of GFRP or KFRP and the case where the bush 9 made of PTFE or modified PPO having a low dielectric loss tangent is used, the PTFE or modified PPO is compared.
Has a dielectric loss tangent of about 0.0002 to 0.0007 and about 0.015 to 0.04 of GFRP and KFRP, the dielectric loss is also improved to about 1/100. As for the size of the bush 9, the dielectric loss depends on the feed line 1.
Since it is inversely proportional to the square of the distance from, if the radius is several mm, the influence of the element 2 made of GFRP or KFRP can be ignored.

Here, examples of the material of the bush 9 include PTFE and modified PPO having a low dielectric loss tangent. These materials have a dielectric loss tangent of about 0.0002 to 0.0
007, about 0.015 of GFRP and KFRP
Although smaller than 0.04, the coefficient of thermal expansion is about 50 to 1
00ppm / ° C, which is about 3-14 of GFRP and KFRP
Larger than ppm / ℃, GFRP and KFR
Since it is not easy to mold as compared with P, the element 2
Is unsuitable as a material and is not integrally molded with the bush 9.

Here, as a method of fixing the power supply line 1, as shown in FIG. 13, a spacer 12 made of a dielectric material may be fixed to the groove 13 provided in the element 2 by adhesion or fitting. By using a material having a low dielectric constant and a low dielectric loss tangent, the same effect can be obtained.

Alternatively, the method for fixing the power supply line 1 is as shown in FIG.
The tab 14 made of a dielectric material as shown in FIGS.
May be fixed to the element 2 by adhesion or the like,
By using a material having a low dielectric constant and a low dielectric loss tangent as the material of the tab 14, the same effect can be obtained.

Example 4. 17 is a configuration diagram showing a fourth embodiment of the present invention, and FIG. 18 is an enlarged view of a fixing portion. In the figure, reference numerals 1, 2, 4, 5, 6, 7 are the same as those in the first embodiment, and 13 is a groove provided in the element 2 as in the third embodiment. The feeder line 1 is held in the hollow of the groove 13 by the string 7. Further, the ends of the string 7 are bonded and fixed at a position apart from the power supply line 1 as shown in the first embodiment.

Because of the above-mentioned structure, the position of the feeder line 1 is fixed by the string 7 and the element 2.
Also, by fixing it, it can withstand environmental conditions, and
Since nothing can be placed in the vicinity of the power supply line 1, the dielectric loss in the vicinity of the fixed part of the power supply line 1 is reduced, the electrical performance is less deteriorated, and heat generation in the fixed part of the power supply line 1 is almost eliminated.

Example 5. FIG. 19 is a configuration diagram showing a fifth embodiment of the present invention, and FIG. 20 is an enlarged view of a fixing portion. In the figure, reference numerals 1, 2, 4, 5, 6 are the same as those in the above-mentioned Example 1, 15 is a heat-melting string of a dielectric material, and the feeder line 1 is connected to the element 2 by the heat-melting string 15. Later,
The knot of the heat-fusible string 15 is heat-melted and fixed so as not to untie.

For example, the material of the heat-fusible string 15 may be nylon or the like. Nylon has a dielectric loss tangent of about 0.02, a melting temperature of about 300 ° C, and a heat resistant temperature of about 250 ° C. Therefore, the knot can be easily fixed by applying a trowel of about 300 ° C. to the knot, and there is no problem in terms of electrical characteristics and heat resistance.

Because of the above-mentioned structure, the position of the power supply line 1 is fixed by the heat-melting strap 15 and the element 2, and the fixing allows it to withstand the environmental conditions. Since the power supply line 1 and the power supply line 1 are not in close contact with each other over a wide area like an adhesive, but are in partial contact with each other, the fusion loss due to the melter near the fixed portion of the power supply line 1 is small, The deterioration of the electric performance is small, and the heat generated in the fixed portion of the power supply line 1 is almost eliminated.

[0037]

According to the method for fixing the feed line of the helical antenna of the present invention, the dielectric loss and the heat generation of the dielectric due to the dielectric loss can be prevented by keeping the adhesive having a large dielectric loss away from the feed line, and the electric characteristics can be improved. Well, there is an effect that it is possible to obtain a helical antenna that can withstand a high power antenna output.

Further, by fixing the feeder line with a dielectric material having a low dielectric constant and a low dielectric loss tangent, it is possible to prevent the dielectric material from generating heat due to the dielectric loss of the components to be fixed, have good electrical characteristics, and provide a large power antenna output. There is an effect that it is possible to obtain a helical antenna that can withstand even this.

According to the present invention, since the power supply line is fixed through the dielectric having a low dielectric constant and a low dielectric loss tangent, it is possible to eliminate a component having a large dielectric loss from the periphery of the power supply line, so that heat generation due to the dielectric loss can be prevented. Therefore, there is an effect that a helical antenna having good electric characteristics and capable of withstanding a high power antenna output can be obtained.

Also, by hanging the feeder line with a string,
Since parts with large dielectric loss can be eliminated from the periphery of the power supply line, there is an effect that heat generation due to dielectric loss can be prevented, electrical characteristics are good, and a helical antenna that can withstand high power antenna output can be obtained.

According to the present invention, since the adhesive having a large dielectric loss can be eliminated by fixing the power supply line with a heat-melting string, the heat generation due to the dielectric loss can be prevented, the electric characteristics are good, and the power is large. There is an effect that it is possible to obtain a helical antenna that can withstand the antenna output.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a method of fixing a feeder line of a helical antenna according to a first embodiment of the present invention.

FIG. 2 is an enlarged view showing details of a fixing portion in a method for fixing a feeder line of a helical antenna according to a first embodiment of the present invention.

FIG. 3 is a cross-sectional view of a fixing portion of a method for fixing a feeder line of a helical antenna according to a first embodiment of the present invention.

FIG. 4 is an enlarged view showing an example of how to bind the string in the method for fixing the feed line of the helical antenna according to the first embodiment of the present invention.

FIG. 5 is an enlarged view showing an example of a string adhesive fixing portion of a method for fixing a feed line of a helical antenna according to a first embodiment of the present invention.

FIG. 6 is an enlarged view showing an example of the configuration of another method of binding the straps in the method for fixing the feed line of the helical antenna according to the first embodiment of the present invention.

FIG. 7 is an enlarged view showing an example of another method of binding the string with the feeder fixing method for the helical antenna according to the first embodiment of the present invention.

FIG. 8 is a configuration diagram showing a method of fixing a feed line of a helical antenna according to a second embodiment of the present invention.

FIG. 9 is an enlarged view showing a feeder fixing portion of a helical antenna according to a second embodiment of the present invention.

FIG. 10 is a configuration diagram showing an example of a method for fixing a feeder line of a helical antenna according to a third embodiment of the present invention.

FIG. 11 is an enlarged view showing a feeder fixing portion of a helical antenna according to a third embodiment of the present invention.

FIG. 12 is a detailed view showing the assembly of the feeder fixing portion of the helical antenna according to the third embodiment of the present invention.

FIG. 13 is a configuration diagram showing another example of the feeder fixing portion of the helical antenna according to the third embodiment of the present invention.

FIG. 14 is a configuration diagram showing another example of a method for fixing a feed line of a helical antenna according to a third embodiment of the present invention.

FIG. 15 is an enlarged view showing another example of the feeder fixing portion of the helical antenna according to the third embodiment of the present invention.

FIG. 16 is a detailed view showing the assembly of another example of the feeder fixing portion of the helical antenna according to the third embodiment of the present invention.

FIG. 17 is a configuration diagram showing a method of fixing a feeder line of a helical antenna according to a fourth embodiment of the present invention.

FIG. 18 is an enlarged view showing a feeder fixing portion of the helical antenna according to the fourth embodiment of the present invention.

FIG. 19 is a configuration diagram showing a method for fixing a feed line of a helical antenna according to a fifth embodiment of the present invention.

FIG. 20 is an enlarged view showing a feeder fixing portion of a helical antenna according to a fifth embodiment of the present invention.

FIG. 21 is a configuration diagram showing a conventional feeder fixing method for a helical antenna.

FIG. 22 is an enlarged view of a feed line bonding portion of a conventional helical antenna.

FIG. 23 is a configuration diagram showing another example of a conventional feed line fixing method for a helical antenna.

FIG. 24 is an enlarged view showing a feeder fixing portion of a conventional helical antenna.

FIG. 25 is an enlarged view showing a cross section of a feeder fixing portion of a conventional helical antenna.

[Explanation of symbols]

1 feeding line, 2 elements, 3 adhesive, 4 cups, 5 screws, 6 connectors, 7 strings, 8 covers,
9 bush, 10 hole, 11 arrow, 12 spacer, 13 groove, 14 tab, 15 heat-melting string.

Claims (5)

[Claims] 1. A helical antenna in which a feed line is spirally provided in a dielectric tube, wherein the dielectric tube and the feed line are connected with a dielectric string so that the tip of the string is on the dielectric tube. A method for fixing a feed line of a helical antenna, characterized in that it is fixed by adhesion at a position away from the feed line. 2. In a helical antenna having a feed line provided on a spiral, the feed line is sandwiched between a side surface of the dielectric cylinder and a part having a lower dielectric constant and dielectric loss tangent than the dielectric cylinder. A method for fixing a feed line of a helical antenna, which is fixed. 3. A helical antenna in which a feed line is spirally provided in a dielectric tube, wherein the feed line is made of a component different from that of the dielectric tube. A method for fixing a feed line of a helical antenna, characterized in that the electric wire is fixed to the above-mentioned dielectric cylinder through a low component. 4. A feed line for a helical antenna, characterized in that, in a helical antenna in which a feed line is spirally provided in a dielectric tube, the feed line is fixed to the dielectric tube so that the feed line is suspended by a strap of the dielectric. Fixing method. 5. A helical antenna in which a feed line is spirally provided in a dielectric cylinder, wherein the dielectric cylinder and the feed line are connected by a heat-melting dielectric string, and the knot is melted by heat to form the above. A method for fixing a feed line of a helical antenna, characterized in that it is fixed to a dielectric cylinder.