JP2010148025A - Antenna device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antenna device that achieves a low-scattering cross section, and reduces mutual interference. <P>SOLUTION: This antenna device includes: a dielectric tube bent to bring both ends close to each other, having both the ends arranged in the vicinity of a ground conductor 2, and including an ionizing gas in the inside; first and second electrodes arranged at both the ends of the dielectric tube in the inside of the dielectric tube; a plasma excitation power source 7 for keeping the ionizing gas in a plasma state; a first wire 9 for connecting the plasma excitation power source 7 to the first electrode; a second wire 10 for connecting the plasma excitation power source 7 to the second electrode; a high-frequency power source 8 arranged on the ground conductor 2; and a high-frequency power coupling means for coupling high-frequency power output from the high-frequency power source 8 to at least either of the first and second wires 9, 10. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an antenna device that realizes a low scattering cross-sectional area when not in use, or an antenna device that has a plurality of antennas that are arranged close to each other and used for switching.

In general, an antenna used in the defense field is desired to realize a low scattering cross section, and this type of antenna is for realizing a low scattering cross section when not used.
Further, in a direction detection system that switches between a plurality of antennas arranged close to each other, the conductor of the unused antenna is configured to be electrically transparent, thereby improving the accuracy of direction detection.

Conventionally, an example of a plasma antenna capable of making an antenna conductor electrically transparent when not in use has been proposed (for example, see Patent Document 1).
FIG. 10 is a block diagram showing a conventional antenna device described in Patent Document 1. In FIG.
In FIG. 10, the inside of the dielectric tube 101 contains an ionizing gas, and the ionizing gas in the dielectric tube 101 is changed to a plasma state by supplying power from the external power source 102.

Since the ionizing gas in the plasma state acts as a conductor at high frequencies, the dielectric tube 101 is supplied to the ionizing gas in the plasma state by supplying high frequency power from the high frequency power source 103 via the coupling element 104. Operates as an antenna.
At this time, in order to prevent a high frequency current from flowing through the wiring connecting the dielectric tube 101 and the external power source 102, filters 105 and 106 for cutting the high frequency are provided.

  According to the conventional antenna apparatus shown in FIG. 10, when the external power supply 102 is turned off, the ionizing gas in the dielectric tube 101 changes from the plasma state to the normal state, and the conductivity at high frequency is lost. The body tube 101 will appear to be electrically transparent to high frequencies.

  However, in the antenna apparatus of FIG. 10, the dielectric tube 101 is linear and the wiring of the external power supply 102 is connected to both ends of the dielectric tube 101, so the antenna radiation direction is the longitudinal direction of the dielectric tube 101. At the center point of the direction, the maximum is in the plane orthogonal to the longitudinal direction. Therefore, the wiring or the external power source 102 is configured to cross the radiation surface, which becomes a factor that disturbs the radiation characteristics of the antenna. Moreover, although the influence of the disturbance of the radiation characteristics of the antenna can be somewhat reduced by the filters 105 and 106, the influence cannot be completely removed.

US Pat. No. 5,594,456

Since the conventional antenna device has a configuration that disturbs the radiation characteristics of the antenna, there is a problem that even if a filter is provided, the influence cannot be completely removed.
In general, the antenna device is installed in free space, and the wiring associated therewith is also arranged in free space. Since the wiring has a high scattering cross section, only the dielectric tube that operates as an antenna has a low scattering cross section. However, the entire apparatus has a problem that it has a high scattering cross section.

  The present invention has been made in order to solve the above-described problems. In an antenna device that realizes a low scattering cross-sectional area when not in use, or an antenna device that has a plurality of antennas that are arranged in close proximity and used for switching. An object of the present invention is to obtain an antenna device with reduced mutual interference.

  The antenna device according to the present invention is a ground tube, a dielectric tube that is bent so that both ends are close to each other, and both ends are disposed in the vicinity of the ground conductor, and contains an ionizing gas inside, and inside the dielectric tube, First and second electrodes provided at both ends of the dielectric tube, a plasma excitation power source for maintaining the ionizing gas in a plasma state, and a first wiring connecting the plasma excitation power source and the first electrode High-frequency power output from the high-frequency power source to at least one of the second wiring that connects the plasma excitation power source and the second electrode, the high-frequency power source provided on the ground conductor, and the first and second wirings High-frequency power coupling means for coupling the two.

  According to the present invention, mutual interference can be reduced in an antenna device that realizes a low scattering cross-sectional area when not in use or an antenna device that has a plurality of antennas that are arranged close to each other and are used in a switching manner.

Embodiment 1 FIG.
FIG. 1 is a perspective view showing an antenna apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a circuit diagram showing a circuit configuration on the back side of a ground conductor 2 in FIG.
In FIG. 1, a dielectric tube 1 constituting an antenna radiating portion is filled with an ionizing gas inside, and is bent at a central portion so as to have an elongated U-shape so that both ends are close to each other. is doing.

  Both ends of the dielectric tube 1 are disposed in the vicinity of the ground conductor 2, and the dielectric tube 1 is disposed on the surface of the ground conductor 2 so that the bent portion is positioned away from the ground conductor 2. The conductor 2 is arranged in the vertical direction.

A first electrode terminal 3 and a second electrode terminal 4 for supplying power to the dielectric tube 1 are disposed at both ends of the dielectric tube 1, and the first and second electrode terminals 3, 4 are It is in contact with the ionizing gas inside the dielectric tube 1 and close to the ground conductor 2.
The first wiring 9 integrated with the first electrode terminal 3 is inserted into the first hole 5 on the ground conductor 2, and the second wiring 10 integrated with the second electrode terminal 4 is connected to the ground conductor 2. The second hole 6 is inserted.

  In FIG. 2, a plasma excitation power source 7 for power supply for plasma excitation is connected to the front ends of the first and second wirings 9 and 10 located on the back side of the ground conductor 2. The plasma excitation power source 7 is disposed on the back surface of the ground conductor 2.

Further, in the vicinity of the first and second holes 5 and 6, a high-frequency power source 8 is provided between the first wiring 9 and the ground conductor 2 via a capacitor 13.
A capacitor 11 is provided between the first and second wirings 9 and 10, and a capacitor 12 is provided between the first and second wirings 9 and 10 and the ground conductor 2.

  The first wiring 9 passes through the first hole 5 so as to connect the first electrode terminal 3 and the plasma excitation power source 7. Similarly, the second wiring 10 passes through the second hole 6 so as to connect the second electrode terminal 4 and the plasma excitation power source 7.

The first and second wirings 9 and 10 are connected via a plurality of capacitors 11 at intervals shorter than the high-frequency wavelength λ to be used.
The high frequency power supply 8 is connected to the first wiring 9 via the capacitor 13.
The capacitor 12 connecting the first and second wirings 9 and 10 and the ground conductor 2 has a high frequency from the position of the first wiring 9 to which the high frequency power supply 8 is connected toward the plasma excitation power supply 7 side. It is arranged at a position about 1/4 of the wavelength λ.

Note that the capacitances of all the capacitors 11 to 13 are set so as to be substantially short-circuited at a high frequency and substantially open at the frequency of the plasma excitation power source 7.
The distance between the bent portion of the dielectric tube 1 and the ground conductor 2 has a length of about ¼ of the wavelength λ of the high frequency.

Next, the operation principle according to the first embodiment of the present invention shown in FIGS. 1 and 2 will be described.
First, in the state where the plasma excitation power source 7 is ON, low frequency power for exciting plasma is supplied to the first and second electrode terminals 3 and 4.
At this time, the ionizing gas inside the dielectric tube 1 is in a plasma state, and the dielectric tube 1 operates as a conductor at a high frequency.

Further, since the first and second electrode terminals 3 and 4 are in contact with the plasma in the dielectric tube 1, the plasma and the electrode terminals 3 and 4 are in a conductive state.
Since the first and second wirings 9 and 10 are electrically connected through the capacitor 11 at a shorter interval than the high-frequency wavelength λ to be used, both have the same potential at a high frequency. Acts as a line.

A high frequency power supply 8 is connected to the first wiring 9 through the capacitor 13 in the vicinity of the first hole 5, and the high frequency power supply 8 includes the ground conductor 2, the first and second wirings 9, High-frequency power is supplied to a high-frequency line formed from 10.
This high frequency power is transmitted not only to the dielectric tube 1 side that operates as an antenna but also to the plasma excitation power source 7 side.

However, the high-frequency power transmitted to the plasma excitation power source 7 side is totally reflected at the position of the capacitor 12 and therefore is not supplied from the capacitor 12 to the plasma excitation power source 7 side.
Thereby, it is possible to prevent the high frequency power from being consumed in the plasma excitation power source 7.

Further, since the capacitor 12 is located at a distance of about ¼ of the wavelength λ from the high frequency power supply point, the impedance of the capacitor 12 from the high frequency power supply point is ideally infinite. It does not affect the antenna impedance.
In addition, the first and second wirings 9 and 10 are electrically connected to the ground conductor 2 at a high frequency by the capacitor 12 and are kept at the same potential except for the antenna feeding portion. It is possible to suppress unnecessary high-frequency radiation from the wirings 9 and 10.

  According to the above configuration, since the high frequency power is supplied to the first and second electrode terminals 3 and 4 of the dielectric tube 1 in the same phase, the U-shaped conductor is equivalent to one conductor at a high frequency. It operates as a monopole antenna on the ground conductor 2.

In this case, if the distance between the bent portion of the dielectric tube 1 and the ground conductor 2 has a length of about ¼ of the wavelength λ of the high frequency, the impedance of the antenna becomes a resonance state, and the high frequency power supply Impedance matching with 8 is easy.
Moreover, since all antenna components other than the dielectric tube 1 (see FIG. 2) are hidden behind the ground conductor 2, there is an advantage that the radiation characteristics of the antenna are not disturbed.

On the other hand, when the plasma excitation power supply 7 is OFF, the dielectric tube 1 operates as a dielectric at a high frequency.
Further, since all antenna components other than the dielectric tube 1 are hidden behind the ground conductor 2, the front side of the ground conductor 2 acts as a free space.

Therefore, it is possible to reduce the scattering cross section viewed from the front side of the ground conductor 2.
Further, when a plurality of antenna elements are arranged on the front side of the ground conductor 2 and a plurality of antennas are switched, the unused antenna portion is made almost free space by turning off the plasma excitation power source 7 of the unused antenna. As a result, there is an advantage that the radiation characteristics of the operating antenna are not disturbed.

  As described above, the antenna device (FIGS. 1 and 2) according to Embodiment 1 of the present invention is bent so that both ends are close to the ground conductor 2 and both ends are disposed in the vicinity of the ground conductor 2. The dielectric tube 1 containing an ionizing gas inside, the first and second electrode terminals 3 and 4 provided at both ends of the dielectric tube 1 inside the dielectric tube 1, and plasma of the ionizing gas And a plasma excitation power source 7 for maintaining the state.

  In addition, the first wiring 9 that connects the plasma excitation power source 7 and the first electrode terminal 3, the second wiring 10 that connects the plasma excitation power source 7 and the second electrode terminal 4, and the ground conductor 2 The provided high frequency power supply 8 and high frequency power coupling means for coupling high frequency power output from the high frequency power supply 8 to at least one of the first and second wirings are provided.

The dielectric tube 1 is disposed so as to extend in the vertical direction from the ground conductor 2.
The high-frequency power coupling means includes a capacitor 12 that short-circuits at least one of the first and second wirings 9 and 10 to the ground conductor 2 at a high frequency, and the first and second wirings 9 and 10 It is disposed close to the conductor 2.

  Further, the high frequency power supply 8 is connected between at least one of the first and second wirings 9 and 10 and the ground conductor 2, and from the connection position of the capacitor 12 to the first or second wirings 9 and 10. The first or second electrode terminal 3 or 4 is disposed at a position separated from the high-frequency wavelength λ by ¼ toward the first or second electrode terminal 3 or 4 side.

Accordingly, mutual interference can be reduced in an antenna device that realizes a low scattering cross-sectional area when not in use or an antenna device that has a plurality of antennas that are arranged in close proximity and used for switching.
That is, it is possible to realize a low scattering cross section of the antenna when not in use and to reduce mutual interference.

  In FIG. 1, the dielectric tube 1 is arranged in a straight line in the vertical direction of the ground conductor 2, but the dielectric tube 1 may be formed in a helical shape and arranged parallel to the ground conductor 2. Even if it is bent, the same effect is obtained.

  Furthermore, in order to make the impedance of the capacitor 12 larger from the high-frequency power supply point from the high-frequency power supply 8, the distance between the capacitor 12 and the high-frequency power supply point is set to about ¼ of the high-frequency wavelength λ. However, as an alternative, it goes without saying that the same effect can be obtained even if an inductor is inserted in series in the installation portion of the capacitor 12.

Embodiment 2. FIG.
Although the ground conductor 2 is used in the first embodiment (FIGS. 1 and 2), the ground conductor 2 may be deleted as shown in FIG.
FIG. 3 is a side view showing an antenna apparatus according to Embodiment 2 of the present invention. Components similar to those described above (see FIG. 1) are denoted by the same reference numerals as those described above, or “a” after the reference numerals. The detailed description is omitted.

In FIG. 3, since the ground conductor 2 is unnecessary, the above-described capacitor 12 is also unnecessary.
In this case, since the basic configuration is the same as that of the first embodiment (FIGS. 1 and 2), only the portions different from the above will be described.

In FIG. 3, the dielectric tube 1a is bent in a loop shape.
The high-frequency power supply 8 is connected to the first and second wirings 9 and 10 via two capacitors 13 inserted into each power supply terminal.

Further, the capacitor 11 inserted between the first wiring 9 and the second wiring 10 is ¼ of the wavelength λ of the high frequency from the position where the high frequency power supply 8 is connected toward the plasma excitation power supply 7 side. It is arranged at a position separated by a certain degree.
In this case, the capacitor 11 (see FIG. 2) is not required in the 1/4 wavelength range on the first and second electrode terminals 3 and 4 side.

Next, the operation principle according to the second embodiment of the present invention shown in FIG. 3 will be described.
First, the operation when the plasma excitation power source 7 is in the ON state will be described.
In this case, since the high frequency power supply 8 is disposed between the first wiring 9 and the second wiring 10, high frequency power is supplied between the first wiring 9 and the second wiring 10.

  Therefore, dielectric tube 1a can be operated as a loop antenna, and a radiation pattern different from the monopole antenna in the first embodiment described above can be realized.

The high frequency power supplied between the first wiring 9 and the second wiring 10 is also transmitted to the plasma excitation power source 7 side, but the high frequency power transmitted to the plasma excitation power source 7 side is Since it is totally reflected at the position, no high frequency power is supplied from the capacitor 11 to the plasma excitation power source 7 side.
Thereby, it is possible to prevent the high frequency power from being consumed in the plasma excitation power source 7.

  Further, since the capacitor 11 is located at a distance of about ¼ of the wavelength λ from the high frequency power supply point, the impedance of the capacitor 11 from the high frequency power supply point is ideally infinite. It does not affect the antenna impedance.

  Further, according to the configuration of FIG. 3, since the first and second electrode terminals 3 and 4 for inducing plasma are arranged close to each other, the first and second wirings 9 and 10 can be used as antenna radiating portions. Since the dielectric tube 1a is not traversed, there is an advantage that the wirings 9 and 10 do not adversely affect the radiation characteristics of the antenna.

Next, the operation when the plasma excitation power source 7 is in the OFF state will be described.
Usually, when an antenna device is installed, the radiating portion is arranged in a free space, and other feeding circuits and the like are arranged in a portion that does not affect the radiation.
In the antenna apparatus of FIG. 3, since only the dielectric tube 1a can be arranged in a free space and the other members can be arranged in a portion that does not affect radiation, the scattering cross section can be reduced.

  Also, when arranging a plurality of antenna elements and switching the plurality of antennas, the plasma excitation power supply 7 of the unused antenna is turned off, so that the unused antenna part acts almost as a free space. This has the advantage of not disturbing the radiation characteristics of the antenna.

  As described above, the antenna device (FIG. 3) according to the second embodiment of the present invention is bent so that both ends thereof are close to each other, and includes the dielectric tube 1a containing ionizing gas inside, and the inside of the dielectric tube 1a. Are provided with first and second electrode terminals 3 and 4 provided at both ends of the dielectric tube 1a, and a plasma excitation power source 7 for keeping the ionizing gas in a plasma state.

  The first wiring 9 connecting the plasma excitation power source 7 and the first electrode terminal 3, the second wiring 10 connecting the plasma excitation power source 7 and the second electrode terminal 4, and the first wiring A high frequency power supply 8 connected between the high frequency power supply 8 connected between the high frequency power supply 8 and the high frequency power supply 8 connected between the first wiring 9 and the second wiring 10. Power coupling means.

The high frequency power coupling means includes a capacitor 11 that short-circuits the first wiring 9 and the second wiring 10 at a high frequency.
The high frequency power supply 8 is disposed at a position separated from the high frequency wavelength λ by ¼ from the position where the capacitor 11 is connected to the first or second electrode terminal 3 or 4 side. .

Thus, as described above, mutual interference can be reduced in an antenna device that realizes a low scattering cross-sectional area when not in use or an antenna device that has a plurality of antennas that are arranged in close proximity and used for switching.
That is, it is possible to realize a low scattering cross section of the antenna when not in use and to reduce mutual interference.

Embodiment 3 FIG.
In addition, in the said Embodiment 2 (FIG. 3), although the ground conductor 2 was deleted, you may use the ground conductor 2 like FIG. 4 and FIG.
4 is a perspective view showing an antenna apparatus according to Embodiment 3 of the present invention, and FIG. 5 is a circuit diagram showing a circuit configuration on the back surface side of the ground conductor 2 in FIG.
4 and 5, the same components as those described above (see FIGS. 1 to 3) are denoted by the same reference numerals as those described above and will not be described in detail.

4 and 5, the basic configuration is the same as that of the first embodiment (FIGS. 1 and 2), and therefore only the parts different from the above will be described here.
In FIG. 4, on the ground conductor 2, a dielectric tube 1a bent in a loop shape having the same shape as that of the second embodiment (FIG. 3) is erected.

In FIG. 5, the first wiring 9 and the second wiring 10 are located at a position about 1/4 of the wavelength λ of the high frequency from the position where the high frequency power supply 8 is connected to the plasma excitation power supply 7 side. A capacitor 11 that connects the two is disposed. Note that the capacitor 11 (see FIG. 2) in the 1/4 wavelength range on the first and second electrode terminals 3 and 4 side is omitted as in the second embodiment (FIG. 3).
Further, the second wiring 10 is provided with a capacitor 12 that connects the second wiring 10 and the ground conductor 2 in the vicinity of the portion of the first wiring 9 to which the high-frequency power supply 8 is connected.

Next, the operation principle according to the third embodiment of the present invention shown in FIGS. 4 and 5 will be described.
First, the operation when the plasma excitation power source 7 is in the ON state will be described.
In this case, the high frequency power supply 8 is connected between the first wiring 9 and the ground conductor 2, and the second wiring 10 and the ground conductor 2 are connected at high frequency via the capacitor 12 in the vicinity of the connection point. Since it is short-circuited, high-frequency power is supplied between the first wiring 9 and the second wiring 10.

  Therefore, the dielectric tube 1a can be operated as a loop antenna, and a radiation pattern different from the monopole antenna of the first embodiment can be realized.

The high frequency power supplied between the first wiring 9 and the second wiring 10 is also transmitted to the plasma excitation power supply 7 side, but the high frequency power transmitted to the plasma excitation power supply 7 side is the capacitor. Therefore, the high frequency power is not supplied from the capacitor 11 to the plasma excitation power source 7 side.
Thereby, it is possible to prevent the high frequency power from being consumed in the plasma excitation power source 7.

  Further, since the capacitor 11 is located at a distance of about ¼ of the wavelength λ from the high frequency power supply point, the impedance of the capacitor 11 from the high frequency power supply point is ideally infinite. It does not affect the antenna impedance.

In addition, the first and second wirings 9 and 10 are electrically connected to the ground conductor 2 at a high frequency by the capacitor 12 and are kept at the same potential except for the antenna feeding portion. It is possible to suppress unnecessary high-frequency radiation from the wirings 9 and 10.
Moreover, since all antenna components other than the dielectric tube 1a are hidden behind the ground conductor 2, there is an advantage that the radiation characteristics of the antenna are not disturbed.

  Further, when the plasma excitation power source 7 is in the OFF state, all the antenna constituent members other than the dielectric tube 1a are hidden behind the ground conductor 2, so that the front side of the ground conductor 2 acts as almost free space. The scattering cross section viewed from the front side of the ground conductor 2 can be reduced.

  Furthermore, when arranging a plurality of antenna elements on the front side of the ground conductor 2 and switching the plurality of antennas, the plasma excitation power source 7 of the unused antenna is turned off so that the unused antenna portion becomes almost free space. As a result, there is an advantage that the radiation characteristics of the operating antenna are not disturbed.

  As described above, the antenna device (FIGS. 4 and 5) according to Embodiment 3 of the present invention is bent so that both ends are close to the ground conductor 2 and both ends are disposed in the vicinity of the ground conductor 2. Dielectric tube 1a containing ionizing gas inside, first and second electrode terminals 3 and 4 provided at both ends of dielectric tube 1a inside dielectric tube 1a, and plasma of ionizing gas And a plasma excitation power source 7 for maintaining the state.

  In addition, the first wiring 9 that connects the plasma excitation power source 7 and the first electrode terminal 3, the second wiring 10 that connects the plasma excitation power source 7 and the second electrode terminal 4, and the ground conductor 2 The provided high frequency power supply 8, the first capacitor 11 that short-circuits the first wiring 9 and the second wiring 10 at high frequency, and the first capacitor 11 that short-circuits between the second wiring 10 and the ground conductor 2 at high frequency. 2 capacitors 12.

The dielectric tube 1 a is formed in a loop shape, and the high frequency power supply 8 is connected between the ground conductor 2 and the first wiring 9.
The second capacitor 12 is arranged at a position separated from the position where the first capacitor 11 is connected by ¼ with respect to the wavelength λ of the high frequency toward the first or second electrode terminal 3 or 4 side. Has been.

Thus, as described above, mutual interference can be reduced in an antenna device that realizes a low scattering cross-sectional area when not in use or an antenna device that has a plurality of antennas that are arranged in close proximity and used for switching.
That is, it is possible to realize a low scattering cross section of the antenna when not in use and to reduce mutual interference.

Embodiment 4 FIG.
In the second embodiment (FIG. 3), the loop-shaped dielectric tube 1a is used. However, as shown in FIG. 6, a T-shaped dielectric tube 1b may be used.
FIG. 6 is a side view showing an antenna apparatus according to Embodiment 4 of the present invention. Components similar to those described above (see FIG. 3) are denoted by the same reference numerals as those described above, or “b” after the reference numerals. The detailed description is omitted.

In FIG. 6, the basic configuration is the same as that of the above-described second embodiment, and therefore only the parts different from the above will be described here.
In this case, a dielectric tube 1b bent in a T shape is used. By using the dielectric tube 1b formed in a T-shape, it can be operated as a folded dipole antenna.

In the folded dipole, since the antenna has a self-balancing action, there is an advantage of suppressing emission of unnecessary current.
Hereinafter, the principle of the self-equilibrium action will be described with reference to FIGS.
FIG. 7 is a block diagram schematically showing a normal dipole antenna, and FIG. 8 is a block diagram schematically showing a folded dipole antenna according to Embodiment 4 of the present invention.

7 and 8, the circuit configuration such as the plasma excitation power source 7 is omitted because measures are taken so as not to affect the antenna at high frequencies.
First, in the normal dipole antenna shown in FIG. 7, wirings 21 and 22 that operate as balanced two wires are connected to the high-frequency power supply 8, and conductor elements 23 and 24 that serve as radiating portions are connected to the ends of the wirings 21 and 22. It is connected.

In this case, a current B1 indicated by a broken line arrow flows through the wiring 21, and a current B2 indicated by a broken line arrow flows through the wiring 22.
In addition, a current A1 indicated by a one-dot chain line flows through the conductor element 23, and a current A2 indicated by a one-dot chain line flows through the conductor element 24.

  In FIG. 7, if the antenna structure is completely symmetrical, A1 = A2 and B1 = B2. Usually, the wirings 21 and 22 are arranged sufficiently close to the high-frequency wavelength λ, so that the current B1 and the current B2 cancel each other, and the power radiated from the wirings 21 and 22 is negligible. become.

  However, if the left-right symmetry is lost due to an error in the antenna structure or other factors, B1 ≠ B2, and a component that does not cancel out between the current B1 and the current B2 is generated, resulting in an unbalanced component. The unbalanced component of the current is radiated as a cross polarized wave of the dipole antenna, and deteriorates the characteristics of the dipole antenna.

  On the other hand, in the folded dipole antenna according to the fourth embodiment of the present invention shown in FIG. 8, since the conductor elements 23a and 24a have a continuous one-stroke shape, even when the left-right symmetry of the antenna structure is broken, Since the antenna shape itself has a balancing effect, the condition of B1 = B2 is maintained.

Therefore, an unbalanced component of current does not occur, and it is possible to prevent deterioration of the characteristics of the dipole antenna.
In addition, although the ground conductor 2 was deleted here, the ground conductor 2 can also be provided.

  As described above, according to the antenna device (FIGS. 6 and 8) according to the fourth embodiment of the present invention, the dielectric tube 1b is formed in a T shape, and the configuration of the folded dipole is one stroke. It has the shape of a calligraphy.

Thereby, it has an affinity with the structure of the plasma antenna which has the dielectric tube 1 (refer FIG. 1) comprised by bending, and there exists an advantage that it is easy to comprise a plasma antenna.
In addition, the antenna constituent members other than the dielectric tube 1b can be separated from the conductor elements 23 and 24 operating as the radiating portions, so that there is an advantage that the radiation characteristics of the antenna are not disturbed.

  Further, when the plasma excitation power source 7 is in the OFF state, the antenna constituent members other than the dielectric tube 1b can be separated from the conductor elements 23 and 24 operating as the radiating portions, so that the scattering cross section is reduced. It becomes possible.

  Also, when arranging a plurality of antenna elements and switching a plurality of antennas, the plasma excitation power supply 7 of the unused antenna is turned off, so that the unused antenna portion acts as almost a free space. There is an advantage that the radiation characteristic of the antenna is not disturbed.

Embodiment 5 FIG.
In the fourth embodiment (FIGS. 6 and 8), the single dielectric tube 1b is used. However, as shown in FIG. 9, the first and second dielectric tubes 1c and 1d are placed close to each other. They may be arranged side by side to constitute a T-shaped dielectric tube as a whole.
FIG. 9 is a side view showing an antenna apparatus according to Embodiment 5 of the present invention. Components similar to those described above (see FIG. 6) are denoted by the same reference numerals as those described above, or “c, Detailed description is omitted with “d”.

In FIG. 9, the first dielectric tube 1c is supplied with power by a first plasma excitation power supply 7c, and the second dielectric tube 1d is supplied with power by a second plasma excitation power supply 7d.
The first and second dielectric tubes 1c and 1d are bent so that both ends thereof are close to each other, and are bent at right angles at the center so that the bent ends are opposite to each other. , L-shaped.

Similar to the first dielectric tube 1c, the second dielectric tube 1d is filled with an ionizing gas.
Further, third and fourth electrode terminals 15 and 16 are provided inside both ends of the second dielectric tube 1d, and each electrode terminal 15 and 16 is provided in the second dielectric tube 1d. It is in contact with ionizing gas.

  The third and fourth wirings 18 and 19 are connected to the third and fourth electrode terminals 15 and 16, and the capacitor 11d is interposed between the third wiring 18 and the fourth wiring 19. Are short-circuited at high frequency.

  The first and second dielectric tubes 1c and 1d having an L shape include a straight portion extending from the first and second electrode terminals 3 and 4 of the first dielectric tube 1c, and a second dielectric tube. The linear portions extending from the third and fourth electrode terminals 15 and 16 of the body tube 1d are arranged so as to be close and parallel to each other, thereby forming a T shape as a whole.

In the first dielectric tube 1c, a first wiring 9 is installed so as to connect the first electrode terminal 3 and the first plasma excitation power source 7c, and the second electrode terminal 4 and the first plasma excitation are connected. The second wiring 10 is installed so as to connect the power supply 7c.
Similarly, in the second dielectric tube 1d, a third wiring 18 is installed so as to connect the third electrode terminal 15 and the second plasma excitation power supply 7d, and the fourth electrode terminal 16 and the second dielectric tube 1d are connected to the second dielectric tube 1d. The fourth wiring 19 is installed so as to connect to the plasma excitation power source 7d.

  A capacitor 11c is disposed between the first wiring 9 and the second wiring 10 at a sufficiently small interval compared to the high-frequency wavelength λ, and similarly, the third wiring 18 and the fourth wiring 19 are connected to each other. Between them, the capacitor 11d is arranged at a sufficiently smaller interval than the high-frequency wavelength λ.

The high frequency power supply 8 is connected between the first wiring 9 and the third wiring 18 through two capacitors 13 inserted in each power supply terminal.
Between the first wiring 9 and the third wiring 18, about a quarter wavelength of the high frequency is separated from the position where the high frequency power supply 8 is connected toward the first and second plasma excitation power supplies 7 c and 7 d. The capacitor 12 is disposed at the position.

  The capacitances of all the capacitors 11c, 11d, 12, and 13 are set so as to be almost short-circuited at high frequencies and almost open at the frequencies of the first and second plasma excitation power supplies 7c and 7d. ing.

Next, the operation principle according to the eighth embodiment of the present invention shown in FIG. 9 will be described.
First, the operation when the plasma excitation power supplies 7c and 7d are in the ON state will be described. Note that description of parts that operate in the same manner as described above is omitted.

  The two straight portions extending from the first and second electrode terminals 3 and 4 of the first dielectric tube 1c are short-circuited at high frequencies in the portions of the first and second wirings 9 and 10. Therefore, it can be regarded as one line. Hereinafter, the first and second wirings 9 and 10 (straight line portions) are referred to as a first bundle.

  Similarly, the two straight portions extending from the third and fourth electrode terminals 15 and 16 of the second dielectric tube 1d are short-circuited at a high frequency in the portions of the third and fourth wirings 18 and 19. Since it is in a state, it can be regarded as one line. Hereinafter, the third and fourth wirings 18 and 19 (straight line portions) are referred to as a second bundle.

Two parallel lines are formed by the first and second bundles, and high-frequency power is excited from the high-frequency power source 8 in these two lines.
The high frequency power is transmitted not only to the first and second dielectric tubes 1c and 1d that operate as antennas, but also to the first and second plasma excitation power sources 7c and 7d, The high frequency power transmitted to the 7d side is totally reflected at the position of the capacitor 12.

  Therefore, since the high frequency power is not supplied from the capacitor 12 to the plasma excitation power supplies 7c and 7d, it is possible to prevent the high frequency power from being consumed in the first plasma excitation power supply 7c or the second plasma excitation power supply 7d. It becomes possible.

  Further, since the capacitor 12 is located at a distance of about ¼ of the wavelength λ from the high frequency power supply point, the impedance of the capacitor 12 from the high frequency power supply point is ideally infinite. It does not affect the antenna impedance.

  The high frequency power excited between the first bundle and the second bundle is from the first and second dielectric tubes 1c and 1d (dipole antennas) disposed at the tips of the first and second bundles. Radiated.

  According to the antenna device of FIG. 9, the antenna constituent members other than the first and second dielectric tubes 1 c and 1 d can be separated from the dipole antenna, so that there is an advantage that the radiation characteristics of the antenna are not disturbed. .

  Further, when the first and second plasma power supplies 7c and 7d are in the OFF state, the antenna constituent members other than the dielectric tubes 1c and 1d can be separated from the dipole antenna, so that the scattering cross section is reduced. It becomes possible to do.

Further, when a plurality of antenna elements are arranged and a plurality of antennas are switched, the unused antenna portions are almost free space by turning off the first and second plasma power supplies 7c and 7d of the unused antennas. Therefore, there is an advantage that the radiation characteristics of the operating antenna are not disturbed.
In addition, although the ground conductor 2 was deleted here, the ground conductor 2 can also be provided.

  As described above, the antenna device according to Embodiment 5 of the present invention is bent in such a manner that both ends are close to each other, the bent end portion is bent in the first perpendicular direction, and the first containing ionizing gas therein. The dielectric tube 1c and the first dielectric tube 1c are juxtaposed in parallel, bent so that both ends are close to each other, and the bent end portion is a second side opposite to the first perpendicular direction. A second dielectric tube 1d that is bent in a right angle direction and contains an ionizing gas therein, and the first and second dielectric tubes 1c and 1d form a T-shape as a whole. Yes.

  Further, in the first dielectric tube 1c, in the first and second electrode terminals 3 and 4 provided at both ends of the first dielectric tube 1c, and in the second dielectric tube 1d, The first and second electrode terminals 15 and 16 provided at both ends of the second dielectric tube 1d and the first plasma for maintaining the ionizing gas in the first dielectric tube 1c in a plasma state An excitation power source 7c and a second plasma excitation power source 7d for holding the ionizing gas in the second dielectric tube 1d in a plasma state are provided.

  The first wiring 9 connecting the first plasma excitation power source 7 c and the first electrode terminal 3, and the second wiring 10 connecting the first plasma excitation power source 7 c and the second electrode terminal 4. A third wiring 18 that connects the second plasma excitation power supply 7d and the third electrode terminal 15, and a fourth wiring 19 that connects the second plasma excitation power supply 7d and the fourth electrode terminal 16. A high-frequency power source 8 connected between the first wiring 9 and the third wiring 18 and a capacitor 12 that short-circuits the first wiring 9 and the third wiring 18 at a high frequency.

Further, the high-frequency power source 8 is located at a position separated from the high-frequency wavelength λ by ¼ from the position where the capacitor 12 is connected toward the first to fourth electrode terminals 3, 4, 15, 16. Has been placed.
Thereby, there can exist an effect similar to the above-mentioned and Embodiment 1-4.

It is a perspective view which shows the antenna apparatus which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows the structure of the back surface side of the ground conductor in FIG. It is a side view which shows the antenna apparatus which concerns on Embodiment 2 of this invention. It is a perspective view which shows the antenna device which concerns on Embodiment 3 of this invention. It is a circuit diagram which shows the structure of the back surface side of the ground conductor in FIG. It is a side view which shows the antenna apparatus which concerns on Embodiment 4 of this invention. It is a block diagram which shows the normal dipole antenna for demonstrating the effect by Embodiment 4 of this invention. It is a block diagram which shows the folding | turning dipole antenna for demonstrating the effect by Embodiment 4 of this invention. It is a side view which shows the antenna apparatus which concerns on Embodiment 5 of this invention. It is a circuit block diagram which shows the conventional antenna apparatus.

Explanation of symbols

  1, 1a, 1b Dielectric tube, 1c 1st dielectric tube, 1d 2nd dielectric tube, 2 Ground conductor, 3rd electrode terminal, 4 2nd electrode terminal, 7 Plasma excitation power supply, 7c 1st 1 plasma excitation power supply, 7d second plasma excitation power supply, 9 first wiring, 10 second wiring, 8 high frequency power supply, 11, 12 capacitor, 11 first capacitor, 12 second capacitor, 15 3rd Electrode terminal, 16 4th electrode terminal, 18 3rd wiring, 19 4th wiring.

Claims (9)

With ground conductors,
A dielectric tube that is bent so that both ends are close to each other and the both ends are arranged in the vicinity of the ground conductor, and contains an ionizing gas inside;
Inside the dielectric tube, first and second electrode terminals provided at both ends of the dielectric tube;
A plasma excitation power source for maintaining the ionizing gas in a plasma state;
A first wiring connecting the plasma excitation power source and the first electrode terminal;
A second wiring connecting the plasma excitation power source and the second electrode terminal;
A high-frequency power source provided on the ground conductor;
High-frequency power coupling means for coupling high-frequency power output from the high-frequency power source to at least one of the first and second wirings;
An antenna device comprising: The high-frequency power coupling means is constituted by a capacitor that short-circuits at least one of the first and second wirings with respect to the ground conductor at a high frequency,
The first and second wirings are arranged close to the ground conductor,
The high-frequency power source is connected between at least one of the first and second wirings and the ground conductor, and is connected to the first or second wiring from the connection position of the capacitor with respect to the first or second wiring. The antenna device according to claim 1, wherein the antenna device is disposed at a position separated by a quarter of the wavelength of the high frequency toward the electrode terminal side. A dielectric tube which is bent so that both ends are close to each other and contains an ionizing gas inside;
Inside the dielectric tube, first and second electrode terminals provided at both ends of the dielectric tube;
A plasma excitation power source for maintaining the ionizing gas in a plasma state;
A first wiring connecting the plasma excitation power source and the first electrode terminal;
A second wiring connecting the plasma excitation power source and the second electrode terminal;
A high frequency power source connected between the first wiring and the second wiring;
High-frequency power coupling means for coupling high-frequency power output from the high-frequency power source between the first wiring and the second wiring;
An antenna device comprising: The high-frequency power coupling means includes a capacitor that short-circuits the first wiring and the second wiring at a high frequency,
The high-frequency power source is disposed at a position separated from the wavelength of the high-frequency by ¼ from the position where the capacitor is connected toward the first or second electrode terminal side. The antenna device according to claim 3. With ground conductors,
A dielectric tube that is bent so that both ends are close to each other and the both ends are arranged in the vicinity of the ground conductor, and contains an ionizing gas inside;
Inside the dielectric tube, first and second electrode terminals provided at both ends of the dielectric tube;
A plasma excitation power source for maintaining the ionizing gas in a plasma state;
A first wiring connecting the plasma excitation power source and the first electrode terminal;
A second wiring connecting the plasma excitation power source and the second electrode terminal;
A high-frequency power source provided on the ground conductor;
A first capacitor that short-circuits the first wiring and the second wiring at a high frequency;
A second capacitor that short-circuits between the second wiring and the ground conductor at a high frequency;
With
The high-frequency power source is connected to the ground conductor at a position separated from the high-frequency wavelength by a quarter from the position where the first capacitor is connected toward the first or second electrode terminal. Connected to the first wiring,
The second capacitor is arranged at a position separated from the wavelength of the high frequency by 1/4 from the position where the first capacitor is connected toward the first or second electrode terminal side. An antenna device characterized by that.   The antenna device according to claim 1, wherein the dielectric tube is disposed so as to extend in a vertical direction from the ground conductor.   The antenna device according to any one of claims 3 to 5, wherein the dielectric tube is formed in a loop shape.   The antenna device according to claim 3, wherein the dielectric tube is formed in a T shape. A first dielectric tube that is bent so that both ends thereof are close to each other and a bent end portion is bent in a first right angle direction, and an ionizing gas is contained therein;
Arranged adjacent to the first dielectric tube, bent so that both ends thereof are close, and the bent end is bent in a second right angle direction opposite to the first right angle direction; A second dielectric tube containing an ionizing gas therein;
First and second electrode terminals provided at both ends of the first dielectric tube inside the first dielectric tube;
Third and fourth electrode terminals provided at both ends of the second dielectric tube inside the second dielectric tube;
A first plasma excitation power source for maintaining the ionizing gas in the first dielectric tube in a plasma state;
A second plasma excitation power source for maintaining the ionizing gas in the second dielectric tube in a plasma state;
A first wiring connecting the first plasma excitation power source and the first electrode terminal;
A second wiring connecting the first plasma excitation power source and the second electrode terminal;
A third wiring connecting the second plasma excitation power source and the third electrode terminal;
A fourth wiring connecting the second plasma excitation power source and the fourth electrode terminal;
A high frequency power source connected between the first wiring and the third wiring;
A capacitor for short-circuiting the first wiring and the third wiring at a high frequency;
With
The high-frequency power source is disposed at a position separated from the wavelength of the high-frequency by ¼ from the position where the capacitor is connected toward the first to fourth electrode terminals. Antenna device.

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