JP4537928B2 - Antenna device - Google Patents

Description

  The present invention relates to an antenna device, and more particularly to an antenna device capable of changing the radiation direction of electromagnetic waves in a wide range even with a simple structure.

  When performing large-capacity wireless transmission such as transmission / reception of video signals between cameras and receivers of wireless camera systems used in broadcast station program production, and transmission / reception of data via wireless LAN, a wide-band millimeter wave band is applied. The

  When the relative position of the transmitting antenna and the receiving antenna varies greatly depending on the usage environment, the antenna mounted on the millimeter wave band wireless transmission system may be capable of changing the radiation direction of electromagnetic waves in a wide range according to the usage environment. desirable.

  Further, in order to attach the antenna to the millimeter-wave band wireless transmission device itself, the space is generally limited, so the antenna needs to have a small and simple configuration.

  As a millimeter-wave band antenna having a small and simple configuration, there is a surface wave antenna or a leaky wave antenna. A typical surface wave antenna can be a dielectric rod antenna composed of a dielectric rod, and a typical leaky wave antenna is a dielectric leaky wave composed of a dielectric line having a periodic structure. An antenna can be mentioned.

  The dielectric rod antenna radiates a radio wave from the end of the dielectric rod antenna in the propagation direction of the radio wave of the dielectric rod antenna, and the leaky wave antenna radiates a radio wave in a direction different from the propagation direction of the radio wave on the dielectric line.

  And the dielectric rod antenna apparatus and leaky wave antenna apparatus which can change the radiation | emission direction of an electromagnetic wave have already been proposed (for example, refer patent document 1 and patent document 2).

  As shown in FIG. 8, the conventional dielectric rod antenna device disclosed in Patent Document 1 is provided with a reflecting member 192 along the dielectric rod antenna 191, thereby changing the radiation direction of the radio wave to the dielectric rod antenna. It is possible to tilt about 15 degrees with respect to the 191 axis.

  Further, the conventional leaky wave antenna device disclosed in Patent Document 2 includes a propagation path in which a ground plane conductor 201 and a dielectric substrate 202 are arranged in parallel via a spacer 203 as shown in FIG.

  A plurality of metal strips 204 are provided at predetermined intervals on the upper surface of the dielectric substrate 202. Further, a metal plate 205 is disposed above the dielectric substrate 202 at a predetermined interval and perpendicular to the propagation direction of the radio wave, but the metal plate 205 is within a predetermined angle in a plane perpendicular to the propagation direction of the radio wave. It can be rotated.

  The radio wave propagates from the metal plate 205 toward the metal strip 204, leaks from the metal strip 204, and is emitted into the air.

Then, by changing the inclination of the metal plate 205, the radiation direction of the radio wave can be controlled.
Japanese Patent Laid-Open No. 06-244628 ([0007], FIG. 1) JP 2003-338706 A ([0031], FIG. 1)

  In order to stably transmit a large amount of information, it is necessary to increase the ratio (C / N ratio) between received power and noise power. As one method for increasing the C / N ratio, it is conceivable to increase the transmission power radiated in the direction of the receiving antenna as much as possible.

  Therefore, in the antenna applied to the wireless camera system, the relative position of the transmission antenna and the reception antenna changes depending on the use environment, and therefore it is necessary to be able to change the radio wave radiation direction in a wide range.

  Considering the fact that when using a wireless camera indoors, the receiving antenna is installed above the wireless camera to ensure visibility, and when using it outdoors, the receiving antenna is often installed horizontally with respect to the wireless camera. It is desirable that the radio wave radiation direction can be changed by 90 degrees or more according to the use environment.

  Furthermore, in order to increase the C / N ratio, it is conceivable to increase the antenna gain. However, the antenna directivity becomes sharper as the antenna gain is increased. Therefore, when shooting while moving with a wireless camera, the relative position of the transmitting antenna and the receiving antenna changes from moment to moment. It is desirable that the direction can be changed continuously and in a wide range.

  However, the dielectric rod antenna disclosed in Patent Document 1 has a problem that the radiation direction of radio waves cannot be changed according to the use environment.

  Further, the dielectric leaky wave antenna disclosed in Patent Document 2 has a problem that the range of change is limited, although the radio wave radiation direction can be changed according to the use environment.

  Although it is possible to expand the radio wave radiation range using both surface wave antennas and leaky wave antennas, it is necessary to have a configuration that can switch the feed circuit that supplies radio waves to each antenna, and the structure is complicated It cannot be avoided.

  The present invention has been made to solve the above-described conventional problems, and has as its first object to provide an antenna device that can change the radiation direction of electromagnetic waves over a wide range of 90 degrees or more with a simple configuration. To do.

  It is a second object of the present invention to provide an antenna device that can change the radiation direction of radio waves in a wide range and continuously with a simple configuration.

An antenna device according to the present invention includes a columnar dielectric rod antenna that propagates electromagnetic waves in a slow wave mode, a plurality of hollow members through which the dielectric rod antenna penetrates a hollow portion, and the plurality of hollow members at predetermined intervals. look including a connecting member for connecting the dielectric rod antenna, the plurality of hollow members radiates radio waves in a first direction in a state of contacting with each other, the arrangement of the plurality of hollow members at regular intervals In such a state, a radio wave is emitted in a second direction different from the first direction .

  With this configuration, the radio wave radiation direction can be changed over a wide range and continuously with a simple configuration.

An antenna device according to the present invention includes a columnar dielectric rod antenna that propagates an electromagnetic wave in a slow wave mode, and a plurality of the dielectric rod antennas periodically disposed in the propagation direction of the electromagnetic wave on the dielectric rod antenna on the dielectric rod antenna. a columnar body, seen including a connecting member for connecting the plurality of pillars at predetermined intervals, the dielectric rod antenna radiates radio waves in a first direction in a state in which the plurality of columnar bodies in contact with each other And it may have the composition which radiates an electric wave in the 2nd direction different from the 1st direction in the state where these pillars are arranged at regular intervals .

  The antenna device according to the present invention may have a configuration in which the connecting member is a flexible connecting material.

  The antenna device according to the present invention may have a configuration in which the connection member is an elastic connection material.

An antenna device according to the present invention includes a columnar dielectric rod antenna that propagates electromagnetic waves in a slow wave mode, and a periodic structure through which the dielectric rod antenna penetrates a hollow portion, and the periodic structure includes a hollow portion. A plurality of hollow members through which the dielectric rod antenna penetrates, and a connecting member that connects the plurality of hollow members at a predetermined interval, and the dielectric rod antenna is in a state in which the periodic structure is fitted. It has a configuration that radiates radio waves in a first direction and radiates radio waves in a second direction different from the first direction in a state where the periodic structure is removed . The connecting member may be formed of a hollow body through which the dielectric rod antenna penetrates a hollow portion.

  With this configuration, the radiation direction of the electromagnetic wave can be changed over a wide range of 90 degrees or more with a simple configuration.

  The antenna device according to the present invention may have a configuration including a conductive plate that covers one end of the periodic structure.

  An object of the present invention is to provide an antenna device having an effect that the radiation direction of a radio wave can be changed in a wide range and continuously with a simple configuration by changing the interval between a plurality of circular rings through which a dielectric rod antenna passes. It can be done.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The antenna device according to the present invention, in principle, gives periodic perturbation to the slow wave propagation means for propagating the electromagnetic wave in the slow wave mode and the electromagnetic wave propagating through the slow wave propagation means when approaching the slow wave propagation means. Propagation mode conversion means for converting the propagation mode of electromagnetic waves to fast wave mode, and relative position change means for changing the relative position of the slow wave propagation means and the propagation mode conversion means. In the following embodiments, the electromagnetic waves are assumed to be millimeter wave radio waves.
(First embodiment)
FIG. 1 is a perspective view of an antenna device 1 according to a first embodiment of the present invention, in which a columnar dielectric rod antenna 11 that propagates electromagnetic waves in a slow wave mode, and the dielectric rod antenna 11 penetrates a hollow portion. A plurality of hollow members 12 and a connection member 13 that connects the plurality of hollow members 12 at a predetermined interval.

  In the first embodiment, the connecting member 13 is a flexible material, and may be a flexible sheet or cloth made of a dielectric or a conductor.

  The slow wave propagation means is a dielectric rod antenna 11, and the propagation mode conversion means is a hollow member 12 made of a conductor or a dielectric.

  Then, the relative distance can be changed by switching between a state where the connecting member 13 is bent and the hollow member is integrated so as not to function as a periodic structure, and a state where the connecting member 13 is extended and the hollow member functions as a periodic structure. Corresponds to means.

  As shown in the enlarged perspective view of FIG. 2 (a), the feeding portion 14 installed at the base of the dielectric rod antenna 11 is a first waveguide in which a rectangular waveguide 15 having a rectangular cross section is attached to the peripheral wall. 141, a tapered portion 142, and a second waveguide 143 into which the dielectric rod antenna 11 is inserted.

  Next, the operation of the antenna device of the first embodiment will be described. It is assumed that the cross-sectional shapes of the dielectric rod antenna 11 and the power feeding unit 14 are circular.

The radio wave propagating through the rectangular waveguide 15 in the TE ₁₀ mode is first supplied to the first waveguide 141 and converted into the TM ₀₁ mode. The TE ₁₀ mode is a mode having no electric field component in the Y-axis direction and having only a magnetic field distribution. In the TM ₀₁ mode, the magnetic field lines are concentrically distributed in the cross section of the first waveguide 141, and the magnetic field The amplitude and phase are modes that are axially symmetrically distributed with respect to the central axis (Z-axis direction) of the first waveguide 141.

The radio wave fed from the rectangular waveguide 15 to the first waveguide 141 and converted into the TM ₀₁ mode propagates in the Z-axis direction through the first waveguide 141 and passes through the tapered portion 142 to the second wave. Propagates to the waveguide 143. The tapered portion 142 is installed to expand the diameter of the first waveguide 141 to the diameter of the dielectric rod antenna 11.

  The radio wave propagating through the second waveguide 143 is fed to the dielectric rod antenna 11. Here, the insertion end of the dielectric rod antenna 11 into the second waveguide 143 is preferably formed in a tapered shape in order to suppress reflection of radio waves.

The second waveguide 143 may include a funnel portion 144 that opens in the extending direction of the dielectric rod antenna 11 as shown in FIG. By providing the funnel portion 144, it is possible to efficiently transmit the radio wave propagating through the second waveguide 143 in the TM ₀₁ mode to the dielectric rod antenna 11.

  FIG. 3 is a perspective view showing a state in which the dielectric rod antenna 11 is fitted to the hollow member 12, in which the connecting member 13 is bent and the plurality of hollow members 12 are brought into contact with each other (a). The connection member 13 is extended to show a state (b) in which a plurality of hollow members 12 are arranged at regular intervals.

In the state (a) in which the hollow members 12 are in contact with each other, the plurality of hollow members 12 do not function as a periodic structure, so that radio waves are not perturbed and the dielectric rod antenna 11 remains in the TM ₀₁ mode. It propagates and is emitted from the upper end of the dielectric rod antenna 11 as a conical beam having a null in the Z direction. The radiation direction (Q) of the conical beam is about 20 degrees around the Z axis.

  In the state (b) in which the connection member 13 is extended and the plurality of hollow members 12 are arranged at regular intervals, the plurality of hollow members 12 arranged at intervals function as a periodic structure, and a dielectric rod Perturbs the radio wave propagating through the antenna 11. As a result, the radio wave is converted to the fast wave mode and is emitted omnidirectionally with respect to the Z axis in a direction (Q ″) different from the radiation direction (Q) of the conical beam emitted from the dielectric rod antenna 11.

As described above, in the antenna device of the first embodiment, the radiation direction of the radio wave is changed by changing the interval between the hollow members 12 fitted to the columnar dielectric rod antenna 11. It becomes possible.
(Second Embodiment)
The antenna device of the second embodiment is different from that of the first embodiment in that the connection member 13 is an elastic member such as a spring or rubber, and other configurations are the same as those of the first embodiment.

  In the second embodiment, the slow wave propagation means is the dielectric rod antenna 11 and the propagation mode conversion means is the hollow member 12 as in the first embodiment. Then, the relative distance can be changed by switching between the state in which the connecting member 13 is compressed and the hollow member is integrated so as not to function as the periodic structure, and the state in which the connecting member 13 is extended and the hollow member functions as the periodic structure. Corresponds to means.

  The operation of the antenna device of the second embodiment will be described with reference to FIG.

As shown in FIG. 4A, when the elastic body as the connection member 13 is compressed to the maximum and the gaps between the plurality of hollow members 12 are minimized, the plurality of hollow members 12 are separated from the power feeding unit 14. The fed radio wave is not perturbed, propagates through the dielectric rod antenna 11 in the TM ₀₁ mode, and is radiated from the upper end of the dielectric rod antenna 11 as a conical beam having a null in the Z direction. The radiation direction (Q) of the conical beam is about 20 degrees around the Z axis.

  As shown in FIG. 4B, when the elastic body that is the connection member 13 is stretched to some extent, the plurality of hollow members 12 extend in the axial direction (Z-axis direction) of the dielectric rod antenna 11. Function as. Therefore, the radio wave propagating in the axial direction through the dielectric rod antenna 11 is perturbed by the hollow member 12, and the propagation mode of the radio wave is changed from the slow wave mode to the fast wave mode.

  As a result, the radio wave is omnidirectional with respect to the axial direction (Z-axis direction) of the dielectric rod antenna 11 in a direction (Q ′) different from the radiation direction (Q) of the conical beam radiated from the dielectric rod antenna 11. To be emitted.

  As shown in FIG. 4C, when the elastic body as the connection member 13 is extended to the maximum extent, the plurality of hollow members 12 function as a periodic structure having a longer period than that in FIG. Therefore, the radio wave propagating in the axial direction through the dielectric rod antenna 11 is perturbed by the hollow member 12, and the propagation mode of the radio wave is changed from the slow wave mode to the fast wave mode.

  As a result, the radio wave has an axial direction (Z-axis direction) of the dielectric rod antenna 11 in a direction (Q ″) (≠ direction Q ′) different from the radiation direction (Q) of the conical beam radiated from the dielectric rod antenna 11. ) Is emitted omnidirectionally.

  In the second embodiment, since the radiation direction of the radio wave can be changed by changing the interval between the hollow members 12, the dielectric rod antenna 11 may be a dielectric line.

As described above, according to the second embodiment, by changing the distance between the hollow members 12 fitted to the dielectric rod antenna 11, the radiation direction of the radio wave can be continuously changed. .
(Third embodiment)
The antenna device of the third embodiment is that the connecting member 13 is a rigid dielectric, and the hollow member 12 connected by the rigid dielectric connecting member 13 is detachable from the dielectric rod antenna 11. Unlike the first embodiment, other configurations are the same as those of the first embodiment.

  That is, in the third embodiment, the plurality of hollow members 12 connected by the rigid dielectric connecting member 13 are removed from the dielectric rod antenna 11 and are fitted to the dielectric rod antenna 11. The change between the two corresponds to the relative position changing means.

  The operation of the antenna device of the third embodiment will be described with reference to FIG.

As shown in FIG. 5A, when the plurality of hollow members 12 connected by the rigid connection member 13 are removed from the dielectric rod antenna 11, the radio waves propagating through the dielectric rod antenna 11 are perturbed. The radio wave propagates through the dielectric rod antenna 11 in the TM ₀₁ mode and is radiated from the upper end of the dielectric rod antenna 11 as a conical beam having a null in the Z direction. The radiation direction (Q) of the conical beam is about 20 degrees around the Z axis.

  As shown in FIG. 5B, when a plurality of hollow members 12 connected by a rigid dielectric connecting member 13 are fitted to a dielectric rod antenna 11, the plurality of hollow members 12 are dielectric rods. It functions as a periodic structure extending in the axial direction (Z-axis direction) of the antenna 11. Therefore, the radio wave propagating in the axial direction (Z-axis direction) through the dielectric rod antenna 11 is perturbed by the hollow member 12, and the propagation mode of the radio wave is changed from the slow wave mode to the fast wave mode.

  As a result, the radio wave is omnidirectional with respect to the axial direction (Z-axis direction) of the dielectric rod antenna 11 in a direction (Q ″) different from the radiation direction (Q) of the conical beam radiated from the dielectric rod antenna 11. To be emitted.

  FIG. 6 is a graph showing measured values of radiation patterns in the XZ plane (vertical plane). The vertical axis of polar coordinates is the Z axis (vertical direction), and the horizontal axis is the X axis (horizontal direction). Also, the Z axis and the X axis indicate the measurement gain (dBi). Here, the number of the hollow members 12 is 12. When twelve hollow members 12 connected by the rigid connection member 13 are removed from the dielectric rod antenna 11, the radiation pattern is mainly in the direction of about ± 20 degrees from the Z axis as shown in 6a. The beam becomes a conical beam-like pattern having a null in the Z-axis direction.

  On the other hand, when twelve hollow members 12 connected by the rigid connecting member 13 are mounted on the dielectric rod antenna 11, the radiation pattern is formed by the main beam in the X-axis direction as shown in 6b. It becomes an omnidirectional pattern in the horizontal plane.

As described above, according to the third embodiment, it is possible to change the radiation direction of radio waves by inserting and removing the hollow member 12 to and from the dielectric rod antenna 11.
(Fourth embodiment)
The antenna device of the fourth embodiment is different from the third embodiment in that a metal reflector 16 is provided at one end of a plurality of hollow members 12 connected by a rigid connection member 13. The configuration is the same as in the third embodiment.

  The operation of the fourth embodiment will be described with reference to FIG. 7, but a plurality of hollow members 12 connected by the rigid connection member 13 shown in FIG. 7A are removed from the dielectric rod antenna 11. Since the operation is the same as that of the third embodiment, the description thereof is omitted.

  As shown in FIG. 7B, when the hollow member 12 provided with the metal reflector 16 at one end is attached to the dielectric rod antenna 11, the dielectric rod antenna 11 is axially (Z-axis direction). ) Is perturbed, and the propagation mode of the radio wave is converted from the slow wave mode to the fast wave mode.

  As a result, the radio wave is omnidirectional with respect to the axial direction (Z-axis direction) of the dielectric rod antenna 11 in a direction (Q ″) different from the radiation direction (Q) of the conical beam radiated from the dielectric rod antenna 11. Radiated.

  The dielectric rod antenna 11 to which the hollow member 12 is attached functions as a leaky wave antenna. However, since the number of the hollow members 12 is finite, the length of the leaky wave antenna is also finite, and all of the radio waves fed from the power feeding unit 14 are present. Is converted into a fast wave mode and is not radiated as a leaky wave, and a part of the electric power propagates through the dielectric rod antenna 11 while remaining in the slow wave mode.

  In the present embodiment, the residual power is reflected by the metal reflector 16 provided at one end of the plurality of hollow members 12 connected by the rigid connection member 13, and the dielectric rod antenna 11 is connected to the power feeding unit 14. The axial direction (Z) of the dielectric rod antenna 11 in a direction (Q ″) different from the radiation direction (Q) of the conical beam radiated from the dielectric rod antenna 11 and perturbed again by the hollow member 12. (Axial direction) is emitted omnidirectionally.

  The residual power increases as the number of the hollow members 12 is small and the axial length of the dielectric rod antenna 11 of the hollow member 12 is shorter. In the absence of the metal reflector 16, the residual power is not only radiated as a side rope (unnecessary radiation) from the tip of the dielectric rod antenna 11, but also the gain and radiation efficiency of the antenna are reduced.

  In the present embodiment, the residual power is reflected by providing the metal reflector 16 and can be re-radiated by the hollow member 12. Therefore, even when the residual power is large, generation of a side rope and a decrease in radiation efficiency are achieved. Can be suppressed.

  FIG. 8 is a graph showing measured values of radiation patterns when eight hollow members 12 connected by the connecting members 13 are attached to the dielectric rod antenna 11. The vertical axis of polar coordinates indicates the Z axis (vertical direction), and the horizontal axis indicates the X direction (horizontal direction), which represents the measurement gain (dBi).

  8a is a radiation pattern in the case where the metal reflector 16 is not provided, and a side rope is generated in a direction of about ± 20 degrees with respect to the Z axis, and a side lobe level 8c in a direction forming about +20 degrees with respect to the Z axis is It is -2.7 dB with respect to the main beam level.

  8b is a radiation pattern in the case where the metal reflector 16 is provided, and it can be seen that the side lobe level 8d in the direction of about +20 degrees with the Z-axis is greatly improved to -16 dB with respect to the main beam level. .

  As described above, by providing the metal reflector 16 at one end of the plurality of hollow members 12 connected by the rigid connection member 13, it is possible to suppress the occurrence of side lobes caused by residual power. Become.

In addition, the number of hollow members 12 can be reduced, the length of the dielectric rod antenna 11 can be shortened, and the antenna device can be downsized.
(Fifth embodiment)
In the antenna device of the fifth embodiment, the connection member 13 is a rigid dielectric, and the hollow member 12 connected by the connection member 13 made of a rigid dielectric is a second conductor of the dielectric rod antenna 11 and the power feeding unit 14. It is different from the first embodiment in that it can move between the wave tube 143 and the other configuration is the same as that of the first embodiment.

  In the fifth embodiment, a state in which a plurality of hollow members 12 connected by a connecting member 13 made of a rigid dielectric are fitted to the second waveguide 143, and fitted to the dielectric rod antenna 11 is fitted. Changing between the two states corresponds to the relative position changing means.

  The operation of the antenna device according to the third embodiment will be described with reference to FIG.

As shown in FIG. 9A, when the plurality of hollow members 12 connected by the connecting member 13 made of a rigid dielectric material are arranged on the second waveguide 143, the plurality of hollow members 12 are fed. The radio wave fed from the unit 14 does not perturb the radio wave propagating through the dielectric rod antenna 11, and the radio wave propagates through the dielectric rod antenna 11 in the TM ₀₁ mode, and the dielectric rod antenna 11 starts from the upper end of the dielectric rod antenna 11. Is emitted as a conical beam having a null in the axial direction (Z-axis direction). The radiation direction Q of the conical beam is about 20 degrees around the Z axis.

  As shown in FIG. 9B, when a plurality of compressed hollow members 12 connected by a rigid dielectric connecting member 13 are arranged on the dielectric rod antenna 11, the plurality of hollow members 12 are dielectric. It functions as a periodic structure extending in the axial direction (Z-axis direction) of the body rod antenna 11. Therefore, the radio wave propagating in the axial direction (Z-axis direction) through the dielectric rod antenna 11 is perturbed by the hollow member 12, and the radio wave propagation mode is changed from the slow wave mode to the fast wave mode.

  As a result, the radio wave is omnidirectional with respect to the axial direction (Z-axis direction) of the dielectric rod antenna 11 in a direction (Q ″) different from the radiation direction (Q) of the conical beam radiated from the dielectric rod antenna 11. To be emitted.

  As described above, according to the fourth embodiment, it is possible to change the radiation direction of the radio wave by arranging the hollow member 12 on the dielectric rod antenna 11 or the second waveguide 142. It becomes.

(Sixth embodiment)
In the sixth embodiment, the rigid connection member 13 that connects the plurality of hollow members 12 in the third to fifth embodiments is an annular hollow body.

  FIG. 10 is a perspective view of a plurality of hollow members 12 connected by a connection member 13 which is a rigid annular hollow body, and the metal hollow members 12 and the rigid annular connection members 13 are alternately arranged. To constitute a periodic structure. Instead of the metal hollow member 12, a dielectric hollow member having a different dielectric constant from that of the connection member 13 can be used.

  The antenna device of the sixth embodiment is similar to the antenna devices of the third to fifth embodiments, and a plurality of hollow members 12 and dielectric rods connected by a connecting member 13 which is a rigid annular hollow body. By attaching and detaching the antenna 11, it is possible to change the radiation direction of radio waves.

In the first to sixth embodiments described above, the radio wave propagating through the rectangular waveguide 15 is converted to the TM ₀₁ mode by the first waveguide 141. However, the TE ₀₁ mode or TE _It may be converted to ₁₁ mode. However, when converted to the TE ₁₁ mode, the radiation direction of radio waves is not omnidirectional with respect to the axial direction (Z-axis direction) of the dielectric rod antenna 11.

If the feed mode to the dielectric rod antenna 11 is TM ₀₁ mode, the radio wave radiated from the dielectric rod antenna 11 is vertically polarized, and the feed mode to the dielectric rod antenna 11 is TE ₀₁ mode or TE _11. In the mode, the radio wave radiated from the dielectric rod antenna 11 is horizontally polarized.
(Seventh embodiment)
As shown in FIG. 11, the antenna device according to the present invention can also be applied to a dielectric rod antenna 11 composed of a dielectric image line installed on a ground plane 21.

  Spacers 22 are arranged on the ground planes 21 on both sides of the dielectric rod antenna 11, and a plurality of metal or dielectric columnar bodies 23 are periodically arranged on the spacer 22 in the radio wave propagation direction of the dielectric rod antenna 11. . The plurality of columnar bodies 23 are connected by a connection member 13 at regular intervals, and constitute a periodic structure. In addition, the columnar body 23 shall be arrange | positioned in the direction orthogonal to a radio wave propagation direction for a longitudinal direction.

  In the seventh embodiment, the slow wave propagation means is the dielectric rod antenna 11, and the propagation mode conversion means is a plurality of columnar bodies 23. At the same time as switching between the state in which the columnar body 23 is disposed on the spacer 22 and the state in which the columnar body 23 is removed from the spacer, the interval between the columnar bodies 23 disposed on the spacer 22 is expanded and contracted. The change corresponds to the relative position changing means. Note that the connecting member 13 may be a flexible member such as a dielectric sheet or an elastic member such as a spring or rubber.

  The operation of the antenna device according to the seventh embodiment will be described below.

  When the columnar body 23 is removed from the spacer 22, the radio wave fed from the rectangular waveguide 15 to the base of the dielectric rod antenna 11 propagates through the dielectric rod antenna 11 and from the tip of the dielectric rod antenna 11. Radiated in the extending direction (Q) (Y-axis direction) of the dielectric rod antenna.

  When the columnar body 23 is installed on the spacer 22, the radio wave propagating in the dielectric rod antenna 11 is perturbed by the periodic structure which is the columnar body 23, and the dielectric rod antenna 11 transmits the dielectric rod antenna. 11 is radiated in a direction (Q ″) in the YZ plane different from the extending direction (Q) (Y-axis direction) of 11. The expansion / contraction amount of the connecting member 13 made of an elastic body is adjusted to adjust the columnar body 23. By changing the interval, the direction (Q ″) in the XZ plane can be changed.

  On the other hand, if the connecting member 13 is a flexible member, the plurality of columnar bodies 23 do not function as a periodic structure in a state where the connecting members are bent and the columnar bodies 23 are brought into contact with each other. Without receiving, a beam is radiated from the tip of the dielectric rod antenna 11 in the extending direction (Q) of the dielectric rod antenna 11 (Y-axis direction). In addition, in a state where the connecting member 13 is extended and the plurality of columnar bodies 23 are arranged at regular intervals, the radio wave propagating in the dielectric rod antenna 11 is perturbed by the periodic structure composed of the columnar bodies 23. The dielectric rod antenna 11 radiates in a direction (Q ″) in the YZ plane different from the extending direction (Q) (Y-axis direction) of the dielectric rod antenna 11.

In this case, the radio wave fed from the rectangular waveguide 15 in the TE ₁₀ mode propagates through the dielectric rod antenna 11 in the HE ₁₁ mode.

  When radio waves are radiated in the Y-axis direction, the polarization is parallel to the Z axis in the YZ plane, and when radio waves are radiated in a direction different from the Y axis in the YZ plane, Y- The polarization is perpendicular to the beam direction in the Z plane.

  In the seventh embodiment, since the radiation direction of the radio wave can be changed by changing the interval between the columnar bodies 23, the dielectric rod antenna 11 may be a dielectric line.

  As described above, according to the seventh embodiment, by changing the relative position between the periodic structure constituted by the columnar body 23 and the dielectric rod antenna 11, or by changing the period of the periodic structure. The direction of radio wave emission can be changed.

  In the first to seventh embodiments, it is sufficient that the periodic structure constituted by the hollow member or the columnar body can be close to the distance that perturbs the radio wave propagating through the dielectric rod antenna. Direct contact may be made.

  Moreover, although the cross-sectional shapes of the dielectric rod antenna 11 and the power feeding unit 14 are circular, they may be rectangular.

  In the first to seventh embodiments, the electromagnetic waves are radio waves in the millimeter wave band. However, the present invention can be applied to electromagnetic waves other than the millimeter wave band. In particular, in the case of millimeter wave radio waves, a phase shifter is conventionally required to control the antenna directivity, which not only complicates the antenna structure but also increases the power loss. If the antenna device according to the above is applied, the directivity can be controlled not only by a simple structure and a small size but also by a low-loss antenna.

  Further, in the first to seventh embodiments, the slow wave propagation means is a dielectric rod antenna or a dielectric image line, but other surface wave lines, microstrip lines, coplanar lines, slot lines, etc. It may be a printed line.

  The antenna device according to the present invention can be arranged in an array, or the gain of the antenna device can be increased by extending the dielectric rod antenna in the radio wave propagation direction.

  In the above description, the antenna device according to the present invention is a transmission antenna. However, it is obvious that the antenna device according to the present invention can also be applied as a reception antenna.

  As described above, the antenna device according to the present invention has an effect that the radiation direction of electromagnetic waves can be continuously changed over a wide range of 90 degrees or more with a simple configuration, and is effective as an antenna device or the like.

1 is an exploded perspective view of an antenna device according to a first embodiment of the present invention. The perspective view of the electric power feeding part of the antenna apparatus which concerns on this invention The perspective view of the antenna apparatus which concerns on the 1st Embodiment of this invention The perspective view of the antenna device which concerns on the 2nd Embodiment of this invention. The perspective view of the antenna apparatus which concerns on the 3rd Embodiment of this invention. Graph of radiation pattern of antenna device according to third embodiment of the present invention The perspective view of the antenna device which concerns on the 4th Embodiment of this invention. The graph of the radiation pattern of the antenna device which concerns on the 4th Embodiment of this invention The perspective view of the antenna device which concerns on the 5th Embodiment of this invention The perspective view of the hollow member and connection member of an antenna apparatus which concern on the 6th Embodiment of this invention The perspective view of the antenna device which concerns on the 7th Embodiment of this invention A perspective view of a conventional antenna device A perspective view of a conventional antenna device

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Dielectric rod antenna 12 Hollow member 13 Connection member 14 Feed part 15 Rectangular waveguide

Claims (7)

A columnar dielectric rod antenna that propagates electromagnetic waves in slow wave mode;
A plurality of hollow members through which the dielectric rod antenna penetrates a hollow portion;
Look including a connecting member for connecting said plurality of hollow members at predetermined intervals,
The dielectric rod antenna radiates radio waves in a first direction when the plurality of hollow members are in contact with each other, and the first direction when the plurality of hollow members are arranged at a predetermined interval. An antenna device that radiates radio waves in a second direction different from the above . A columnar dielectric rod antenna that propagates electromagnetic waves in slow wave mode;
A plurality of columnar bodies periodically disposed in the propagation direction of the electromagnetic wave of the dielectric rod antenna on the dielectric rod antenna;
Look including a connecting member for connecting the plurality of pillars at predetermined intervals,
The dielectric rod antenna radiates radio waves in a first direction when the plurality of columnar bodies are in contact with each other, and the first direction when the plurality of columnar bodies are arranged at regular intervals. An antenna device that radiates radio waves in a second direction different from the above .   The antenna device according to claim 1, wherein the connecting member is a flexible connecting material.   The antenna device according to claim 1, wherein the connection member is an elastic connection material. A columnar dielectric rod antenna that propagates electromagnetic waves in slow wave mode;
A periodic structure through which the dielectric rod antenna penetrates a hollow portion ,
The periodic structure includes a plurality of hollow members through which the dielectric rod antenna penetrates a hollow portion, and a connection member that connects the plurality of hollow members at a predetermined interval.
The dielectric rod antenna radiates radio waves in a first direction when the periodic structure is fitted, and in a second direction different from the first direction when the periodic structure is removed. An antenna device that emits radio waves . The antenna device according to claim 5, wherein the connection member is formed of a hollow body through which the dielectric rod antenna passes. The antenna device according to claim 5 or 6, comprising a conductor flat plate covering one end of the periodic structure.

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