阅读说明：本技术 带连接器的电介质波导线路 (Dielectric waveguide line with connector ) 是由 吉本洋之 深见大 山中拓 池田友宏 堀部雅弘 加藤悠人 于 2018-05-18 设计创作，主要内容包括：提供能够容易地将电介质波导线路与对方部件连接,并且可形成高频信号的传送损失和反射损失小的连接结构的带连接器的电介质波导线路。一种带连接器的电介质波导线路,其具有电介质波导线路和连接器,其特征在于,上述电介质波导线路由电介质波导线路主体和电介质波导线路端部构成,上述电介质波导线路端部的截面积比上述电介质波导线路主体的截面积小。(Provided is a dielectric waveguide line with a connector, which can easily connect a dielectric waveguide line to a counterpart member and can form a connection structure with a small transmission loss and reflection loss of a high-frequency signal. A dielectric waveguide line with a connector, comprising a dielectric waveguide line and a connector, wherein the dielectric waveguide line is composed of a dielectric waveguide line body and a dielectric waveguide line end portion, and the cross-sectional area of the dielectric waveguide line end portion is smaller than the cross-sectional area of the dielectric waveguide line body.)

1. A dielectric waveguide circuit with a connector, which has a dielectric waveguide circuit and a connector,

the dielectric waveguide line is composed of a dielectric waveguide line body and a dielectric waveguide line end portion, and the sectional area of the dielectric waveguide line end portion is smaller than that of the dielectric waveguide line body.

2. The connectorized dielectric waveguide circuit of claim 1,

the connector has:

a connecting portion configured to be connectable to a counterpart member and slidably hold the dielectric waveguide line body; and

and a fixing portion which is connected to the connecting portion so as to be movable forward and backward and is fixed to the dielectric waveguide line body.

3. The connectorized dielectric waveguide circuit of claim 2,

the connector has a phase adjustment screw for connecting the fixing portion to the connecting portion so as to be able to advance and retreat.

4. The dielectric waveguide circuit with connector as claimed in any one of claims 1 to 3,

the connector has a fitting hole, and a part of the dielectric waveguide line body is fitted in the fitting hole.

5. The connectorized dielectric waveguide circuit of claim 4,

when the diameter of the dielectric waveguide line body is defined as a and the length of a portion of the dielectric waveguide line body that fits into the fitting hole of the connector is defined as X, the following relational expression is satisfied: x is more than or equal to 8 xA.

Technical Field

The present invention relates to a dielectric waveguide line with a connector.

Background

High frequency signals such as microwaves and millimeter waves are transmitted using a dielectric waveguide line, a waveguide tube, a coaxial cable, or the like. Among them, dielectric waveguide lines and waveguides are used as transmission paths for electromagnetic waves in high-frequency regions such as millimeter waves. The dielectric waveguide line is generally composed of an inner layer portion and an outer layer portion, and transmits an electromagnetic wave by side reflection using a difference in dielectric constant between the inner layer portion and the outer layer portion. The outer layer portion may be air. However, from the viewpoint of the stabilization of the dielectric constant and the workability, the outer layer portion is generally a soft, low tan δ and low dielectric constant structure such as a foamed resin. In the practical use of transmission paths, different types of transmission paths are often connected, and a waveguide and a coaxial cable are connected from a dielectric waveguide line, or coaxial cables of different shapes are connected. When such different transmission paths are connected, it is necessary to match both impedances and modes in order to reduce reflection loss at the connection portion. For this matching, a special converter is used or a special structure is adopted, thereby converting the matching impedance and the mode. When the impedance changes sharply, high frequency signals are reflected and transmission efficiency is impaired.

Patent document 1 describes a resonator with a dielectric waveguide having a structure in which one or two dielectric waveguides are inserted into one or two holes provided in a mirror of a fabry-perot resonator, wherein the tip of the dielectric waveguide inserted so as to protrude from the hole provided in the mirror toward a resonance portion is formed to be tapered such as a conical shape.

Patent document 2 describes a coaxial waveguide converter for connecting a circular coaxial line and a rectangular coaxial line, which includes a ridge waveguide in which an inner conductor and an outer conductor are integrated, and in which the inner conductor is changed in a step-like or tapered shape in a longitudinal direction.

Patent document 3 describes a nonradioactive dielectric line in which a dielectric line is provided between conductor plates, and the dielectric line includes at least a dielectric line (line 1) made of a material having a predetermined dielectric constant and a dielectric line (line 2) made of a material having a dielectric constant lower than that of the line 1.

Non-patent document 1 describes that conical horns are provided at both ends of a polyethylene line having a circular cross-sectional shape, and HE is measured₁₁The transmission loss of the pattern.

Patent document 4 describes a method for joining two portions of a dielectric waveguide, the method including the steps of: cutting off the end of the dielectric waveguide to be joined by an accurate transverse cross section perpendicular to the longitudinal axis of the waveguide; combining the flange coupling with the aluminum matching tool; stripping a portion of the cover layer and the shield layer from the dielectric waveguide at the one end to expose a length portion of the core; and matching the corresponding cross sections of the openings of the core and the matching tool exactly in the radial direction with respect to each other.

Disclosure of Invention

Problems to be solved by the invention

The invention aims to provide a dielectric waveguide line with a connector, which can easily connect the dielectric waveguide line with a counterpart member and can form a connection structure with small transmission loss and reflection loss of high-frequency signals.

Means for solving the problems

In order to solve the above problem, a dielectric waveguide line with a connector according to the present invention includes a dielectric waveguide line and a connector, and is characterized in that the dielectric waveguide line is composed of a dielectric waveguide line body and a dielectric waveguide line end portion, and a cross-sectional area of the dielectric waveguide line end portion is smaller than a cross-sectional area of the dielectric waveguide line body.

Effects of the invention

The dielectric waveguide line with a connector of the present invention can easily connect the dielectric waveguide line to a counterpart member such as a hollow metal pipe, and can form a connection structure with small transmission loss and reflection loss of a high-frequency signal by connecting to the counterpart member.

Drawings

Fig. 1 is a cross-sectional view showing an example of a dielectric waveguide line with a connector according to the present invention.

Fig. 2 is a cross-sectional view showing an example of a connection structure for connecting the dielectric waveguide line with connector of the present invention and a converter.

Fig. 3 is a cross-sectional view showing another embodiment of the dielectric waveguide line with connector of the present invention.

Detailed Description

Next, a dielectric waveguide circuit with a connector according to the present invention will be described with reference to the drawings.

The dielectric waveguide line 1 with a connector shown in fig. 1 includes a dielectric waveguide line 11 and a connector 12, and the dielectric waveguide line 11 is composed of a dielectric waveguide line body 11a and a dielectric waveguide line end portion 11 b. The dielectric waveguide line 11 is covered with the outer layer portion 17 except for the portion having the connector 12.

Since the dielectric waveguide line with connector 1 includes the connector 12, it can be easily attached to and detached from a counterpart member (not shown).

The cross-sectional area of the dielectric waveguide line end portion 11b of the dielectric waveguide line with connector 1 is smaller than the cross-sectional area of the dielectric waveguide line body 11 a. Therefore, when the dielectric waveguide line is connected to the hollow metal pipe as a counterpart member (not shown), a connection structure with a small transmission loss and reflection loss can be realized by suppressing a rapid change in impedance between the dielectric waveguide line and the hollow metal pipe.

The shape of the dielectric waveguide line end portion 11b may be a conical shape, a truncated conical shape, a pyramidal shape, or a truncated pyramidal shape, and the shape is a conical shape which is easy to manufacture.

Preferably, the cross-sectional area of the dielectric waveguide line body 11a is 0.008mm²(

1.8THz) or more and 18000mm²(

600MHz) or less. More preferably, 0.28mm²(

300GHz) and 64mm²(

20GHz) or less.

Since high transmission efficiency can be obtained, the cross-sectional area of the dielectric waveguide line end 11b is preferably 1% or more, more preferably 5% or more, and still more preferably 10% or more, with respect to the cross-sectional area of the dielectric waveguide line body 11 a. Further, it is preferably 90% or less, more preferably 80% or less, and still more preferably 70% or less.

Since a rapid change in the dielectric constant can be suppressed, it is also preferable that the cross-sectional area of the dielectric waveguide line end portion 11b gradually or stepwise decreases toward the tip. The rate of decrease in the cross-sectional area of the dielectric waveguide line end portion 11b is preferably 0.1% or more, more preferably 0.5% or more, and still more preferably 1% or more, per 1mm toward the tip. Further, the reduction rate of the cross-sectional area of the dielectric waveguide line end portion 11b is preferably 30% or less, more preferably 20% or less, and still more preferably 10% or less per 1mm toward the tip.

In the dielectric waveguide line with connector 1, the connector 12 has a connecting portion 12a and a fixing portion 12 b. The connecting portion 12a is configured to be connectable to a counterpart member, and is capable of slidably holding the dielectric waveguide line body 11 a. The fixing portion 12b is connected to the connecting portion 12a so as to be able to advance and retreat. The fixing portion 12b is fixed to the dielectric waveguide line body 11 a.

In a communication system typified by a mobile phone, phase management is important. In the transmission path, the difference between the phase of the entrance and the phase of the exit may be adjusted. Therefore, a phase adjuster, a phase shifter, or the like is used that performs phase adjustment by changing the physical length or the electrical length.

In the dielectric waveguide line with connector 1, the fixing portion 12b is connected to the connecting portion 12a of the connector 12 so as to be movable forward and backward, and the position of the dielectric waveguide line end portion 11b in the axial direction with respect to the connecting portion 12a can be precisely adjusted by the forward and backward movement of the fixing portion and the connecting portion, and the phase can be precisely adjusted. For example, in order to adjust the phase of a millimeter wave of 30GHz, the axial position of the dielectric waveguide line end 11b may be adjusted within a range of ± 5 mm. Therefore, it is not necessary to use a phase adjuster or a phase shifter for phase adjustment.

The connecting portion 12a has a hollow projecting portion 19 extending in the axial direction at one end, a male screw 13a connected to the fixing portion 12b at the other end, and a locking portion 14 projecting in the radial direction. The connection portion 12a has a fitting hole 18 and is fitted to the dielectric waveguide line body 11 a. The connecting portion 12a holds the dielectric waveguide line 11a slidably. That is, the connection portion 12a is movable in the axial direction with respect to the dielectric waveguide line 11, and the connection portion 12a is rotatable in the circumferential direction of the dielectric waveguide line 11.

The fixing portion 12b has a female screw 13b at one end, and is coupled to the connecting portion 12a by being screwed with the male screw 13 a. The fixing portion 12b has a fitting hole 18 and is fitted to the dielectric waveguide line body 11 a. Further, a tapered surface 15 having a smaller outer diameter is formed on the other end of the fixed portion 12b toward the other end. When the fastener 16 is pushed in the direction of the female screw 13b, the tapered surface 15 presses the inner surface of the fitting hole 18 in a direction in which the diameter thereof becomes smaller, and the fixed portion 12b is fixed to the dielectric waveguide line body 11a, thereby restricting the movement of the fixed portion 12 b.

In order to precisely adjust the position of the dielectric waveguide line end 11b in the axial direction, the connector 12 may have a phase adjustment screw 13 for connecting the fixing portion 12b to the connecting portion 12a so as to be able to advance and retreat. In the dielectric waveguide line with connector 1 shown in fig. 1, a male screw 13a is formed in the connecting portion 12a, a female screw 13b is formed in the fixing portion 12b, and the male screw 13a and the female screw 13b constitute a phase adjusting screw 13. The external and internal threads may also be chamfered in reverse of the configuration shown in fig. 1.

When the phase adjustment screw 13 is used, the fixing portion 12b is fixed to the dielectric waveguide line body 11a, and therefore, by rotating the connecting portion 12a, the position of the dielectric waveguide line end portion 11b in the axial direction with respect to the connecting portion 12a can be adjusted, and the phase can be adjusted. Further, a fixing member for fixing the connecting portion 12a and the fixing portion 12b after the position adjustment may be further provided. The fixing member may be a member that simultaneously screws the connecting portion 12a and the fixing portion 12b from the radially outer side.

The connector 12 has a fitting hole 18, and a part of the dielectric waveguide line body 11a is fitted in the fitting hole 18. Here, fitting refers to fitting objects of matching shapes. In fig. 1, since the shape of the radial cross section of the fitting hole 18 is the same as the shape of the radial cross section of the dielectric waveguide line body 11a and the size thereof is also substantially the same, the dielectric waveguide line body 11a is in close contact with the inner wall of the fitting hole 18. As a result, the movement of the dielectric waveguide line end 11b in the radial direction is restricted, and at the time of connection, there is no need to adjust the position of the dielectric waveguide line end 11b in the radial direction, and even if the dielectric waveguide line 11 is stretched or bent, the radial position of the dielectric waveguide line end 11b is hard to move, so that the reflection loss can be further suppressed.

In the aspect in which a part of the dielectric waveguide line body 11a is fitted into the fitting hole 18, when a diameter of the dielectric waveguide line body 11a is a and a length of the dielectric waveguide line body 11a fitted into the fitting hole 18 of the connector 12 is X, it is preferable that a relational expression is satisfied: x is more than or equal to 8 xA. When the above relational expression is satisfied, the movement of the dielectric waveguide line end portion 11b in the radial direction is further restricted, and the reflection loss can be further suppressed. The upper limit of the length X is determined by the length of the fitting hole 18 of the connector 12.

A connection structure for connecting the dielectric waveguide line 1 with a connector to a converter will be described with reference to fig. 2.

Fig. 2 is a cross-sectional view showing an example of the above-described connection structure. The connection structure of fig. 2 is composed of the dielectric waveguide line 1 with a connector and the converter 2, and the protrusion 19 of the dielectric waveguide line 1 with a connector is inserted into the hollow metal pipe 21 of the converter 2, and the dielectric waveguide line end 11b is disposed in the hollow metal pipe. The converter 2 has a flange portion 22, and can be connected to a hollow waveguide (not shown) or the like via the flange portion 22. As shown in fig. 2, if the locking projection 24 is provided on the converter 2 and the locking projection 24 is engaged with the locking portion 14 of the connector 12, the dielectric waveguide line with connector 1 can be easily attached and detached. The converter may be provided with a locking portion, and the connector may be provided with a locking projection.

According to the connection structure shown in fig. 2, since the cross-sectional area of the dielectric waveguide line end portion 11b of the dielectric waveguide line 11 is smaller than the cross-sectional area of the dielectric waveguide line body 11a, a rapid change in impedance between the dielectric waveguide line and the hollow metal pipe can be suppressed, and a connection structure with a small transmission loss and reflection loss can be realized. Further, since the connector 12 is provided, the dielectric waveguide line 1 with a connector can be easily attached to and detached from the hollow metal tube 21 of the converter 2.

Further, in the connector 12, since the fixing portion 12b is connected to the connecting portion 12a so as to be able to advance and retreat, even after the dielectric waveguide line 11 is connected to the hollow metal tube 21, by advancing and retreating the connecting portion 12a of the connector 12 with respect to the fixing portion 12b, the position of the dielectric waveguide line end portion 11b with respect to the axial direction of the connecting portion 12a can be precisely adjusted, and the phase can be precisely and extremely easily adjusted.

Further, since a part of the dielectric waveguide line body 11a is fitted in the fitting hole 18 of the connector 12 and the movement of the dielectric waveguide line end portion 11b in the radial direction is restricted, it is not necessary to adjust the position of the dielectric waveguide line end portion 11b in the radial direction at the time of connection, and even if the dielectric waveguide line 11 is stretched or bent, the position of the dielectric waveguide line end portion 11b in the radial direction is hard to move, and therefore, the reflection loss can be further suppressed. When the relation is satisfied: when X is not less than 8 XA, reflection loss can be further suppressed.

The fitting hole 18 of the connector 12 has the same diameter as the hollow 23 in the hollow metal pipe, and is filled with gas. The gas may be air. Since the diameter of the fitting hole 18 of the connector 12 is made equal to the diameter of the hollow 23 in the hollow metal tube, the diameter of the hollow 23 is increased by the thickness of the protruding portion 19 in the radial direction at the portion of the hollow metal tube 21 into which the protruding portion 19 is inserted.

In the connection structure shown in fig. 2, the dielectric waveguide line 1 with a connector is connected to the converter 2, but the dielectric waveguide line 1 with a connector may be connected to a metal pipe having a hollow portion, such as a hollow waveguide or a horn antenna, instead of the converter 2.

Fig. 3 shows a further embodiment of the dielectric waveguide line 1 with connectors. As shown in fig. 3, the connecting portion 12a may also have a curved portion. Even in the case of such a shape, if a part of the dielectric waveguide line body 11a is fitted into the fitting hole 18, the movement of the dielectric waveguide line end portion 11b in the radial direction is restricted, and therefore, the reflection loss can be further suppressed. In this aspect, it is also preferable that the relation: x is more than or equal to 8 xA.

In the connection structure of fig. 2, the protrusion 19 of the dielectric waveguide 1 with a connector is inserted into the hollow metal tube 21 of the converter 2, but the hollow metal tube 21 may be inserted into the fitting hole 18 of the protrusion 19, and the end of the protrusion 19 may be disposed so as to abut against the end of the hollow metal tube 21. When the hollow metal pipe 21 is inserted into the fitting hole 18 of the protrusion 19, the end of the hollow metal pipe 21 is inserted to a position in contact with the dielectric waveguide line body 11 a. The diameter of the fitting hole 18 is increased by the radial thickness of the hollow metal tube 21 by inserting the hollow metal tube 21 into the fitting hole 18 of the protrusion 19. Even in the case of such a configuration, the dielectric waveguide line with connector 1 and the converter 2 can be easily connected by adjusting the positions of the locking projection and the locking portion.

The dielectric waveguide line 11 is preferably formed of Polytetrafluoroethylene (PTFE), low-density PTFE, stretched PTFE, unfired PTFE, tetrafluoroethylene/hexafluoropropylene copolymer resin (FEP), expanded FEP, tetrafluoroethylene/perfluoro (alkyl vinyl ether) copolymer resin (PFA), expanded PFA resin, polyethylene resin, expanded polyethylene resin, polypropylene resin, polystyrene resin, or the like.

The PTFE may be either homopoly-PTFE composed of Tetrafluoroethylene (TFE) alone or modified PTFE composed of TFE and a modified monomer. The above-mentioned modifying monomer is not particularly limited as long as it is copolymerizable with TFE, and examples thereof include perfluoroolefin such as Hexafluoropropylene (HFP), chlorofluoroalkene such as Chlorotrifluoroethylene (CTFE), hydrogen-containing olefin such as trifluoroethylene and vinylidene fluoride (VDF), perfluoroalkyl ethylene, and ethylene. In addition, the modifying monomer used may be one kind or plural kinds.

In the modified PTFE, the amount of the modified monomer unit is preferably 3% by mass or less, more preferably 1% by mass or less, and still more preferably 0.5% by mass or less of the total monomer units. In addition, from the viewpoint of improving moldability and transparency, 0.001 mass% or more is preferable. The modified monomer unit is a part of the molecular structure of the modified PTFE and is derived from the modified monomer, and the whole monomer unit is a part of the molecular structure of the modified PTFE derived from the whole monomer.

The polytetrafluoroethylene has a Standard Specific Gravity (SSG) of 2.130 or more and 2.250 or less, preferably 2.150 or more, and preferably 2.230 or less, and may have non-melt-processability and fibrillating properties. The standard specific gravity is a value measured by a water displacement method in accordance with ASTM D-792 using a sample molded in accordance with ASTM D-489510.5.

The material of the connector is preferably as follows: when the dielectric waveguide 11 is connected to a hollow metal pipe as a counterpart member (not shown), a connection structure in which rapid changes in impedance between the dielectric waveguide and the hollow metal pipe are suppressed and transmission loss and reflection loss are small can be easily realized, and examples thereof include metals such as copper, brass, aluminum, stainless steel, silver, and iron, and resins such as polypropylene, polycarbonate, polyamide, polyether ether ketone, polyphenylene sulfide, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, polystyrene, polyoxymethylene acetal, polybutylene terephthalate, polyphenylene oxide, polyvinyl chloride, polyethylene, and liquid crystal polymer. The metal and the resin may be used alone or in combination of two or more. In particular, the connecting portion 12a is preferably formed of the metal.

In the dielectric waveguide line with connector 1, the dielectric waveguide line 11 is composed of a dielectric waveguide line body 11a and a dielectric waveguide line end portion 11b having a dielectric constant lower than that of the dielectric waveguide line body 11a, and it is preferable that the dielectric waveguide line body 11a and the dielectric waveguide line end portion 11b are integrally formed of the same material without a seam. According to this structure, even in the case where the line path is small, processing and connection are easy, and a connection structure in which transmission loss and reflection loss of a high-frequency signal are smaller can be formed.

In the dielectric waveguide line with connector 1, the dielectric waveguide line 11 includes a dielectric waveguide line body 11a and a dielectric waveguide line end portion 11b having a density lower than that of the dielectric waveguide line body 11a, and the dielectric waveguide line body 11a and the dielectric waveguide line end portion 11b are preferably integrally formed of the same material without a seam. According to this structure, even in the case where the line path is small, processing and connection are easy, and a connection structure in which transmission loss and reflection loss of a high-frequency signal are smaller can be formed.

According to the methods of the patent documents 1 and 2, in the case where the line path such as the dielectric waveguide line is small, it is difficult to process the line path into a special shape, and therefore, it is difficult to use the method as a method for transmitting millimeter waves and sub-millimeter waves. Further, further improvement in transmission efficiency is also required. Further, as described in patent document 1, in the method of inserting and fixing the dielectric waveguide having the tapered structure at the tip into the conversion portion, since the position of the tip of the tapered structure is varied by increasing stress by bending the dielectric waveguide portion, the reflection characteristic of the high-frequency signal is changed at the conversion portion, and the performance is unstable.

Further, according to the method described in patent document 3, in the case of using the dielectric line (line 1) made of a material having a high dielectric constant, electromagnetic waves are input/output through the dielectric line (line 2) made of a material having a low dielectric constant, instead of directly inputting/outputting electromagnetic waves to/from the dielectric line (line 1) made of a material having a high dielectric constant, so that reflection of electromagnetic waves to the line 1 can be suppressed, and input/output of electromagnetic waves is also facilitated. However, two kinds of dielectric lines different in material need to be bonded, and a bonding surface with small reflection is not easily formed.

Further, according to the method of non-patent document 1, it is necessary to attach a horn-shaped jig to the dielectric waveguide line.

When the dielectric waveguide line with a connector of the present invention is used by connecting it to a hollow metal tube, if the dielectric waveguide line has a dielectric waveguide line body and a dielectric waveguide line end portion having a dielectric constant or density lower than that of the dielectric waveguide line body, it is possible to suppress a rapid change in impedance between the dielectric waveguide line and the hollow metal tube, and to realize a connection structure having a small transmission loss and reflection loss.

Further, if the dielectric waveguide line body and the dielectric waveguide line end are integrally formed of the same material without a seam, processing for forming a joint surface is not required, and the transmission efficiency is also excellent. Since impedance variation at the joint surface does not occur even if the dielectric waveguide line is bent by its stress, even the dielectric waveguide line is bent, stable characteristics can be exhibited. That is, even when the dielectric waveguide line body 11a and the dielectric waveguide line end 11b have different dielectric constants or densities, they are preferably formed of the same material and formed without seams, instead of bonding the different materials. In this case, as shown in fig. 1, no joint surface exists on the dielectric waveguide line 11.

When the length of the dielectric waveguide line end 11b is L and the diameter of the dielectric waveguide line body 11a is D, L and D preferably satisfy the following condition.

When D is less than 0.5mm, L/D is 20

When D is in the range of 0.5mm or more and less than 1mm, L/D is 10

When D is in the range of 1mm or more and less than 10mm, L/D is 5 and the maximum value of L is 10 mm.

When D is 10mm or more, L is 10 mm.

In the dielectric waveguide line with connector 1, it is preferable that the dielectric waveguide line body 11a has a dielectric constant of 1.80 or more and 2.30 or less, and the dielectric waveguide line end 11b has a dielectric constant of 2.20 or less. In the dielectric waveguide line with connector 1, it is more preferable that the dielectric constant of the dielectric waveguide line body 11a is 2.05 or more and 2.30 or less, and the dielectric constant of the dielectric waveguide line end portion 11b is 2.20 or less.

The dielectric waveguide line body 11a preferably has a dielectric constant of 1.80 or more and 2.30 or less, more preferably 1.90 or more, and still more preferably 2.05 or more.

Since high transmission efficiency can be obtained, the dielectric constant of the dielectric waveguide line end portion 11b is preferably 2.20 or less, more preferably 2.10 or less, and still more preferably 2.00 or less.

Since a rapid change in the dielectric constant can be suppressed in the dielectric waveguide line end portion 11b, it is also preferable that the dielectric constant gradually or stepwise decreases toward the tip. In the case where the dielectric constant of the dielectric waveguide line end portion 11b decreases toward the tip, it is preferable that the dielectric constant of the tip portion of the dielectric waveguide line end portion 11b is in the above range. The dielectric constant of the dielectric waveguide line end portion 11b is preferably decreased by 0.005% or more, more preferably 0.01% or more, preferably 20% or less, and still more preferably 10% or less per 1mm toward the tip.

It is also preferable that the density of the dielectric waveguide line end portion 11b is lower than that of the dielectric waveguide line main body 11 a. By providing such a difference in density, it is possible to easily suppress a rapid change in dielectric constant, and to suppress reflection loss, thereby obtaining high transmission efficiency.

Preferably, the density of the dielectric waveguide line body 11a is 1.90g/cm³Above and 2.40g/cm³Hereinafter, the density of the dielectric waveguide line end portion 11b is 90% or less with respect to the density of the dielectric waveguide line body 11 a.

Preferably, the density of the dielectric waveguide line body 11a is 1.90g/cm³Above and 2.40g/cm³The following. More preferably, the density is 1.95g/cm³The above. More preferably, the density of the dielectric waveguide line body 11a is 2.25g/cm³The following.

Generally, in a resin line, it is known that the smaller the density, the smaller the dielectric constant. The density is a value measured by a weight in liquid method according to JIS Z8807.

Since high transmission efficiency can be obtained, the density of the dielectric waveguide line end portion 11b is preferably as low as possible, and the density with respect to the dielectric waveguide line body 11a is preferably 90% or less, more preferably 60% or less, and still more preferably 40% or less. From the viewpoint of the strength of the dielectric waveguide line end 11b, the density with respect to the dielectric waveguide line body 11a is preferably 10% or more, and more preferably 30% or more.

In order to suppress a rapid change in the dielectric constant, it is preferable that the density of the dielectric waveguide line end portion 11b gradually or stepwise decreases toward the tip. In the case where the density of the dielectric waveguide line end portion 11b decreases toward the tip, it is preferable that the density of the tip of the dielectric waveguide line end portion 11b is in the above range. The rate of decrease in the density of the dielectric waveguide line end portion 11b is preferably 0.05% or more, more preferably 0.1% or more, and still more preferably 0.5% or more per 1mm toward the tip. In addition, from the viewpoint of the strength of the dielectric waveguide line end portion 11b, the rate of decrease in the density of the dielectric waveguide line end portion 11b is preferably 30% or less, more preferably 20% or less, and still more preferably 10% or less per 1mm toward the tip.

Preferably, the dielectric waveguide line body 11a has a hardness of 95 or more. The hardness is more preferably 97 or more, still more preferably 98 or more, and particularly preferably 99 or more. The upper limit is not particularly limited, and may be 99.9. When the above hardness of the dielectric waveguide line body 11a is within the above range, a dielectric waveguide line having a low dielectric loss tangent while having a high dielectric constant can be easily realized. Further, the dielectric waveguide line is less likely to be broken and to be blocked or broken.

The hardness was measured according to the spring type hardness prescribed in JIS K6253-3.

The hardness greatly contributes to the strength and buckling stability of the dielectric waveguide line, and the higher the hardness, the higher the strength, and the more the dielectric constant variation and increase in dielectric loss tangent at the time of buckling can be suppressed.

Preferably, the dielectric waveguide line body 11a is at 2.45GH_ZDielectric loss tangent of(tan. delta.) is 1.20X 10^-4The following. More preferably, the dielectric loss tangent (tan. delta.) is 1.00X 10^-4Hereinafter, more preferably 0.95X 10^-4The following. The lower limit of the dielectric loss tangent (tan. delta.) is not particularly limited, and may be 0.10X 10^-4Alternatively, it may be 0.80X 10^-4。

The dielectric loss tangent was 2.45GH using a cavity resonator manufactured by Kanto electronics applications of Kanto Kabushiki Kaisha_ZThe following measurements were carried out. The lower the dielectric loss tangent is, the more excellent the transmission efficiency is.

The dielectric waveguide line may be square, circular, or elliptical, but a circular dielectric waveguide line is easier to manufacture than a square, and thus a circular shape is more preferable.

Preferably, the dielectric constant of the dielectric waveguide line end portion 11b is lower than that of the dielectric waveguide line body 11a, and the dielectric constant of the gas in the fitting hole 18 is lower than that of the dielectric waveguide line end portion 11 b. That is, by making the dielectric constant of the dielectric waveguide line end portion 11b lower than that of the dielectric waveguide line body 11a and higher than that of a gas, a rapid change in the dielectric constant can be suppressed, reflection loss can be suppressed, and high transmission efficiency can be obtained.

It is also preferable that the density of the dielectric waveguide line end portion 11b is lower than that of the dielectric waveguide line main body 11 a.

In general, it is known that the smaller the density in the resin line, the smaller the dielectric constant, and in the present invention, the lower the density of the dielectric waveguide line end portion 11b than the density of the dielectric waveguide line main body 11a, the lower the dielectric constant of the dielectric waveguide line end portion 11b, and the lower the reflection loss at the interface with the gas of the fitting hole 18. The density is a value measured by a weight in liquid method according to JIS Z8807.

The cross-sectional shapes of the dielectric waveguide line 11 and the fitting hole 18 may be square, circular, or elliptical, but for the above reasons, the shapes are preferably the same. Further, since the dielectric waveguide line having a circular shape is easier to manufacture than a square shape, it is more preferable that all of them have a circular shape.

The length of the dielectric waveguide line body 11a is preferably 1mm or more and 199mm or less. Further, it is preferable that the length of the dielectric waveguide line end portion 11b is 1mm to 50mm, since the size can be reduced and the rapid change in the dielectric constant can be easily suppressed.

The diameter of the dielectric waveguide line body 11a is generally determined by the dielectric constant of the body, but is about 6mm at 30GHz and about 3mm at 60 GHz.

The outer layer portion 17 may be formed of PTFE similar to the dielectric waveguide 11. The resin composition may be formed of a hydrocarbon resin such as polyethylene, polypropylene, or polystyrene, or may be formed of a foam of these resins.

The inner diameter of the outer layer portion 17 may be 0.1mm to 150mm, and preferably 0.6mm to 10 mm. The outer diameter of the outer layer portion 17 may be 0.5mm to 200mm, and preferably 1mm to 150 mm.

Next, a method of forming the dielectric waveguide line 11 from Polytetrafluoroethylene (PTFE) will be described. The dielectric waveguide line 11 can be obtained by extending the end of the resin line in the longitudinal direction.

The resin strand can be obtained by molding PTFE by a known molding method. Specifically, a PTFE strand can be obtained by mixing PTFE powder with an extrusion aid, molding the mixture into a preform by means of a preforming machine, and extruding the paste of the preform.

Further, the paste extrusion can be carried out even without preforming. Specifically, a PTFE powder is mixed with an extrusion aid, and directly put into a cylinder of a paste extruder, and a PTFE strand can be obtained by paste extrusion.

By extending the end of the obtained resin wire in the longitudinal direction, the dielectric waveguide line 11 can be obtained in which the cross-sectional area of the dielectric waveguide line end portion 11b is smaller than the cross-sectional area of the dielectric waveguide line body 11 a. In this case, when only the portion to be extended is heated, the desired dielectric waveguide line end portion 11b can be easily manufactured. The magnification of the elongation may be 1.2 times or more and 5 times or less.

By the method in which the end of the resin is extended in the longitudinal direction, it is also possible to manufacture the dielectric waveguide line 11 characterized in that the dielectric constant or density of the dielectric waveguide line end portion 11b is smaller than the dielectric constant or density of the dielectric waveguide line main body 11 a.

The resin strand can be held by a tool such as pliers and then stretched in the longitudinal direction. When the sandwiched portion is not extended, the dielectric waveguide line end portion having a truncated cone shape in which the dielectric constant or the density gradually or stepwise decreases toward the tip end and the cross-sectional area gradually or stepwise decreases toward the tip end can be easily formed by cutting the portion.

The dielectric waveguide line 11 is particularly preferably manufactured by a manufacturing method characterized by including: a step (2) of obtaining a resin strand composed of polytetrafluoroethylene; a step (4) of heating the end of the resin wire; and a step (5) of extending the heated end portion in the longitudinal direction to obtain a dielectric waveguide line.

Next, each step will be explained.

In the above production method, it is preferable that, prior to the step (2), the following step (1) is included: polytetrafluoroethylene (PTFE) powder is mixed with an extrusion aid and a preform made of PTFE is molded.

The PTFE powder is produced from a homopolyptfe comprising Tetrafluoroethylene (TFE) alone, a modified PTFE comprising TFE and a modified monomer, or a mixture of these. The above-mentioned modifying monomer is not particularly limited as long as it is copolymerizable with TFE, and examples thereof include perfluoroolefin such as Hexafluoropropylene (HFP), chlorofluoroalkene such as Chlorotrifluoroethylene (CTFE), hydrogen-containing olefin such as trifluoroethylene and vinylidene fluoride (VDF), perfluoroalkyl ethylene, and ethylene. In addition, the modifying monomer used may be one kind or plural kinds.

In the modified PTFE, the amount of the modified monomer unit is preferably 3% by mass or less, more preferably 1% by mass or less, and still more preferably 0.5% by mass or less of the total monomer units. In addition, from the viewpoint of improving moldability and transparency, 0.001 mass% or more is preferable.

The PTFE may have a Standard Specific Gravity (SSG) of 2.130 or more and 2.250 or less, preferably 2.150 or more, and preferably 2.230 or less, and may have non-melt-processability and fibrillating properties. The standard specific gravity is a value measured by a water displacement method in accordance with ASTM D-792 using a sample molded in accordance with ASTM D-489510.5.

The extrusion aid mixed powder obtained by mixing the PTFE powder and the extrusion aid and aging the mixture at room temperature for about 12 hours is put into a preforming machine, and is preformed for 1 to 10MPa, more preferably 1 to 5MPa, and 1 to 120 minutes, thereby obtaining a preform made of PTFE.

Examples of the extrusion aid include hydrocarbon oil and the like.

The amount of the extrusion aid is preferably 10 parts by mass or more and 40 parts by mass or less, more preferably 15 parts by mass or more and 30 parts by mass or less, relative to 100 parts by mass of the PTFE powder.

Step (2)

This step is a step of obtaining a resin strand made of PTFE.

When the preform made of PTFE is molded in step (1), the preform may be extruded by a paste extruder in step (2) to obtain a resin strand.

In the case where a preform made of PTFE is not molded before the step (2), a resin strand can be obtained by mixing PTFE powder with an extrusion aid and then directly charging the mixture into the cylinder of a paste extruder and performing paste extrusion.

When the resin strand includes the extrusion aid, the extrusion aid is preferably transpired by heating the resin strand at 80 ℃ or higher and 250 ℃ or lower for 0.1 hour or more and 6 hours or less.

The cross-sectional shape of the resin strand may be square, circular, or elliptical, but circular resin strands are preferred to be circular because they are easier to manufacture than square. The diameter of the resin strand may be 0.1mm to 150mm, and preferably 0.6mm to 9 mm.

The production method of the present invention may further include a step (3) of heating the resin strand obtained in the step (2).

The specific heating conditions are appropriately changed according to the shape and size of the cross section of the resin strand. For example, the resin strand is preferably heated at 326 to 345 ℃ for 10 seconds to 2 hours. More preferably, the heating temperature is 330 ℃ or higher, and still more preferably 380 ℃ or lower. The heating time is more preferably 1 hour or more and 3 hours or less.

It is presumed that the air contained in the resin wire is released to the outside by heating at the temperature for a predetermined time, and thus a dielectric waveguide line having a high dielectric constant can be obtained. Further, since the resin wire is not completely fired, it is presumed that a dielectric waveguide line having a low dielectric loss tangent can be obtained. Further, by heating at the above temperature for a predetermined time, there is an advantage that the hardness of the resin strand is improved and the strength is increased.

The heating may be performed using a salt bath, a sand bath, a hot air circulation type electric furnace, or the like, and is preferably performed using a salt bath in terms of easiness in controlling the heating conditions. Further, it is also advantageous in that the heating time is short in the above range. The heating using the salt bath can be performed using, for example, a manufacturing apparatus for a sheathed cable described in japanese patent application laid-open No. 2002-157930.

Step (4)

This step is a step of heating the end of the resin strand obtained in step (2). In addition, this step may be a step of heating the end of the resin strand obtained in step (3).

In the step (4), the end of the resin wire is heated, whereby a desired end of the dielectric waveguide line can be easily manufactured.

In the step (4), although not particularly limited, it is preferable to heat a portion of the resin strand, which is 0.8mm to 150mm away from the tip, for example, and more preferably 20mm or less.

The heating temperature in the step (4) is preferably 100 ℃ or higher, more preferably 200 ℃ or higher, and still more preferably 250 ℃ or higher. The heating temperature in the step (4) is preferably 450 ℃ or lower, more preferably 400 ℃ or lower, and still more preferably 380 ℃ or lower.

Step (5)

This step is a step of extending the heated end portion obtained in step (4) in the longitudinal direction to obtain a dielectric waveguide line.

The heated end obtained in step (4) can be held by a tool such as pliers and stretched in the longitudinal direction to perform stretching. When the sandwiched portion is not extended, the dielectric waveguide line end portion having a truncated cone shape in which the dielectric constant or the density gradually or stepwise decreases toward the tip end and the cross-sectional area gradually or stepwise decreases toward the tip end can be easily formed by cutting the portion.

The draw ratio is preferably 1.2 times or more, more preferably 1.5 times or more. The draw ratio is preferably 10 times or less, more preferably 5 times or less.

The elongation rate is preferably 1%/second or more, more preferably 10%/second or more, and still more preferably 20%/second or more. The elongation rate is preferably 1000%/second or less, more preferably 800%/second or less, and still more preferably 500%/second or less.

The manufacturing method of the present invention may further include a step (6) of inserting the dielectric waveguide line obtained in the step (5) into the outer layer portion.

When the outer layer portion is formed of PTFE, it can be produced, for example, by the following method.

An extrusion aid is mixed with a PTFE powder and the mixture is aged at room temperature for 1 to 24 hours, and then the obtained extrusion aid mixed powder is put into a preforming machine and pressurized at 1 to 10MPa for about 30 minutes to obtain a cylindrical preform made of PTFE. The preform made of the above PTFE was extruded by a paste extruder to obtain a hollow cylindrical molded article. When the molded article contains an extrusion aid, the extrusion aid is preferably transpired by heating the molded article at 80 ℃ to 250 ℃ for 0.1 hour to 6 hours. The molded article is stretched to 1.2 to 5 times, more preferably 1.5 to 3 times at 250 to 320 ℃, still more preferably 280 to 300 ℃, to obtain a hollow cylindrical outer layer portion.

Even when the dielectric waveguide line is formed of a polyethylene resin, a polypropylene resin, a polystyrene resin, or the like, the end of the resin line is extended in the longitudinal direction, whereby a dielectric waveguide line having a smaller cross-sectional area at the end of the dielectric waveguide line than the cross-sectional area of the dielectric waveguide line body can be easily formed.