JP6547693B2 - Antenna device - Google Patents

Description

  The present invention relates to an antenna device mounted on a base and having a radome.

  There is known an antenna apparatus in which an antenna for transmitting, receiving or transmitting / receiving an electromagnetic wave is mounted on a base of a flat plate, the base is housed with the antenna and the upper part is hemispherical and the lower part is a cylindrical radome 1).

  In an antenna device mounted on a moving body, it is desirable to reduce the cross-sectional area as viewed from the front in the traveling direction in order to reduce air resistance. It is conceivable to make the base frusto-conical to reduce the cross-sectional area as viewed from the front in the direction of travel.

  The antenna device may provide an opening at the base. The reason for providing an opening is, for example, the following. An opening that passes the wiring to transmit the signal transmitted and received by the antenna to the antenna. Opening for attaching other parts. Openings for maintenance and inspection. When the base is provided with an opening, it is necessary to cover the opening with a lid in order to protect the antenna from rain and rain inside the antenna and to reduce air resistance.

Patent No. 5680207

  The lid for closing the opening provided at the base of the truncated cone needs to be formed in a conical surface. It is difficult to manufacture a lid with a conical surface. A lid with a conical surface is either a molded part using a dedicated mold or manufactured by shaving, which is costly.

  An object of the antenna device according to the present invention is to obtain an antenna device capable of easily manufacturing a lid for closing an opening provided in a base on which the antenna is mounted.

  An antenna device according to the present invention includes an antenna, a radome for housing the antenna, a flange portion to which the radome is attached, a bottom portion on which the antenna is mounted, and a plurality of at least one elliptic cylindrical surface connecting the flange portion and the bottom portion. The base provided with the side part comprised from a curved surface, and the lid which closed the opening provided in the elliptical cylinder surface were provided.

  According to the antenna device of the present invention, it is possible to easily manufacture a lid for closing the opening provided in the base on which the antenna is mounted.

It is a perspective view of an antenna device concerning Embodiment 1 of this invention. FIG. 6 is a perspective view of the antenna device according to Embodiment 1 with the radome removed. FIG. 2 is a perspective view of a radome that the antenna device according to Embodiment 1 has. FIG. 6 is a side view illustrating the positional relationship between the antenna and the radome of the antenna device according to Embodiment 1. FIG. 1 is a front view of an antenna device according to Embodiment 1; 5 is a rear view of the antenna device according to Embodiment 1. FIG. 5 is a right side view of the antenna device according to Embodiment 1. FIG. FIG. 2 is a left side view of the antenna device according to the first embodiment. FIG. 1 is a plan view of an antenna device according to Embodiment 1; 5 is a bottom view of the antenna device according to Embodiment 1. FIG. 5 is a front view of a base of the antenna device according to Embodiment 1. FIG. FIG. 6 is a rear view of a base included in the antenna device according to Embodiment 1. FIG. 5 is a right side view of a base included in the antenna device according to Embodiment 1. 5 is a left side view of a base of the antenna device according to Embodiment 1. FIG. FIG. 6 is a plan view of a base provided in the antenna device according to Embodiment 1. FIG. 6 is a bottom view of a base of the antenna device according to Embodiment 1. FIG. 7 is a diagram for explaining the shape of an elliptic cylindrical surface that constitutes the side surface portion of the base that the antenna device according to Embodiment 1 has. It is a figure explaining the shape of the lid which closes the opening provided in the base which the antenna apparatus which concerns on Embodiment 1 has. It is a front view of the antenna apparatus of a comparative example. It is a rear view of the antenna apparatus of a comparative example. It is a right view of the antenna apparatus of a comparative example. It is a left view of the antenna apparatus of a comparative example. It is a top view of the antenna device of a comparative example. It is a bottom view of the antenna device of a comparative example. It is a front view of the base which the antenna apparatus of a comparative example has. It is a rear view of the base which the antenna apparatus of a comparative example has. It is a right view of the base which the antenna apparatus of a comparative example has. It is a left view of the base which the antenna apparatus of a comparative example has. It is a top view of the base which the antenna apparatus of a comparative example has. It is a bottom view of the base which the antenna apparatus of a comparative example has. It is a figure explaining the shape of the lid which closes the opening provided in the base which the antenna apparatus of a comparative example has. It is a front view of the antenna apparatus which concerns on Embodiment 2 of this invention. FIG. 7 is a rear view of the antenna device according to Embodiment 2; FIG. 10 is a right side view of the antenna device according to Embodiment 2. FIG. 10 is a left side view of the antenna device according to Embodiment 2. FIG. 7 is a plan view of an antenna device according to Embodiment 2; FIG. 10 is a bottom view of the antenna device according to Embodiment 2. FIG. 10 is a front view of a base included in the antenna device according to Embodiment 2. It is a rear view of the base which the antenna apparatus concerning Embodiment 2 has. FIG. 10 is a right side view of a base included in the antenna device according to Embodiment 2. FIG. 10 is a left side view of a base included in the antenna device according to Embodiment 2. FIG. 10 is a plan view of a base provided in the antenna device according to Embodiment 2. FIG. 10 is a bottom view of a base included in the antenna device according to Embodiment 2. It is a figure explaining the shape of the lid which closes the opening provided in the base which the antenna apparatus which concerns on Embodiment 2 has. It is a front view of the antenna apparatus which concerns on Embodiment 3 of this invention. FIG. 10 is a rear view of the antenna device according to Embodiment 3. FIG. 16 is a right side view of the antenna device according to Embodiment 3. FIG. 16 is a left side view of the antenna device according to Embodiment 3. FIG. 10 is a plan view of an antenna device according to Embodiment 3. FIG. 16 is a bottom view of the antenna device according to Embodiment 3. FIG. 16 is a front view of a base included in the antenna device according to Embodiment 3. FIG. 21 is a rear view of a base of the antenna device according to Embodiment 3. FIG. 21 is a right side view of a base included in the antenna device according to Embodiment 3. FIG. 16 is a left side view of a base included in the antenna device according to Embodiment 3. FIG. 16 is a plan view of a base included in the antenna device according to Embodiment 3. FIG. 21 is a bottom view of a base included in the antenna device according to Embodiment 3. It is a figure explaining the shape of the lid which closes the opening provided in the base which the antenna apparatus which concerns on Embodiment 3 has.

Embodiment 1
The structure of the antenna device according to the first embodiment of the present invention will be described using FIGS. 1 to 10. FIG. 1 is a perspective view of an antenna apparatus according to Embodiment 1 of the present invention. FIG. 2 is a perspective view of the antenna device according to the first embodiment with the radome removed. FIG. 3 is a perspective view of a radome of the antenna device according to the first embodiment. FIG. 4 is a side view for explaining the positional relationship between the antenna and the radome of the antenna apparatus according to the first embodiment. 5 to 10 are six views of the antenna device according to the first embodiment. The antenna device 50 is mounted on a mobile body. The front view is a view from the front of the moving direction of the moving body.

  The antenna device 50 includes an antenna 1 that transmits and receives radio waves in a determined frequency band, a radome 2 that houses and protects the antenna 1, and a base 4 that mounts the antenna 1. The antenna 1 is, for example, a circular parabolic antenna. The antenna 1 is controlled in azimuth and elevation so that it points in the direction of the satellite, for example for satellite communication. The antenna device 50 is mounted on a mobile object such as a ship or an aircraft. The base 4 is provided with an attachment portion to the moving body. The radome 2 and the base 4 form a sealed structure, and the antenna 1 and the communication device 20 are housed therein. The communication device may be installed outside the radome. The antenna may be a transmitting antenna or a receiving antenna.

  The radome 2 is formed with a predetermined thickness of a material through which an electromagnetic wave passes. As shown in FIG. 3, the upper part of the radome 2 is hemispherical, and the lower part is substantially cylindrical. The radome 2 has a flange 3 at its lower end. The radome 2 has the same size as the outer periphery of the flange 3 at its central portion, and the diameter slightly decreases as it goes lower. As shown in FIG. 4, a space is provided inside the radome 2 so that the antenna 1 can be oriented in any direction.

  The base 4 is provided with a rectangular opening 5 (shown in FIG. 13) for passing a wire for transmitting a signal transmitted and received by the antenna 1 to the antenna 1. The opening 5 is also used for maintenance and inspection. The rectangular opening 5 is covered with a lid 6 and closed. The lid 6 is removably attached to the base 4 by a suitable method such as screwing.

  11 to 16 show six views of the base 4. The base 4 has a flange 7 to which the flange 3 of the radome 2 is attached, a bottom 8 to be attached to the moving body, and a side 9 connecting the flange 7 and the bottom 8. The thickness of each part of the base 4 is substantially the same. The flange portion 7 is an annular flat plate having a size aligned with the flange 3 of the radome 2. The bottom portion 8 is a figure in which adjacent corners of a regular pentagon are connected by an arc of the same determined radius. Here, a figure in which adjacent corners of a polygon are connected by an arc or an elliptic arc is called an arc-shaped polygon. If the radius of the arc or the major and minor axes of the arc differ depending on the side, it is also called an arc-shaped polygon. A figure in which adjacent corners of a polygon are all connected by an arc of the same radius is called an arc polygon. The bottom 8 and the flange 7 are parallel. The center of gravity of the bottom 8 as a planar figure and the center of gravity of the flange 7 are on the same straight line perpendicular to the bottom 8 and the flange 7. The bottom 8 is smaller than the circle on the inner periphery of the flange 7. The cross-sectional shape of the external shape of the flange portion 7 side of the side surface portion 9 is a perfect circle. By doing so, it can be connected with the annular flange portion 7.

  The side surface portion 9 has a shape in which five elliptic cylindrical surfaces having the same curved surface shape are combined to form a ridgeline between adjacent elliptic cylindrical surfaces. FIG. 17 is a view for explaining the shape of an elliptic cylindrical surface which constitutes the side portion of the base of the antenna device according to the first embodiment. FIG. 17A is a side view when the bottom of the base 4 is directed upward. FIG. 17B is a plan view. FIG. 17C is a view of the elliptic cylindrical surface 10 provided with the opening 5 from the axial direction of the elliptic cylinder indicated by the arrow A in FIG. 17A. FIG. 17D is a view of the elliptic cylindrical surface 10 provided with the opening 5 in a direction perpendicular to the axis of the elliptic cylinder indicated by the arrow B in FIG. 17A.

  The external shape of the side part 9 connected with the flange part 7 is a shape of a perfect circle. Assuming that the diameter of the perfect circle on the flange 7 side is La, the major diameter of the elliptic cylindrical surface is also La. Assuming that the minor axis Lb of the elliptic cylindrical surface is an angle θ between the elliptic cylindrical surface and the plane where the flange portion 7 exists, as shown in FIG. 17, there is a relationship of Lb = La * sin θ. The inclination angle θ and the height of the side portion 9 are appropriately determined in accordance with the size of the bottom portion 8. The elliptical cylindrical surface 10 has the same arc of an ellipse on the flange 7 side and the bottom 8 side.

  The cross-sectional shape of the plane parallel to the bottom portion 8 and the outer shape of the side surface portion 9 is a perfect circle having a diameter La on the flange portion 7 side. The outer shape of the bottom portion 8 is an arc polygon having a distance of La / 2 to the farthest corner from each corner of the regular pentagon. The bottom 8 is a monospaced figure having the same width in all directions perpendicular to its normal. A polygon in which each side of a regular polygon having an odd number of corners is replaced by an arc to form an equal-width figure is called a Roulous polygon. The bottom 8 is a Roulous polygon. The outer shape of the side surface portion 9 is a perfect circle on the flange portion 7 side and is an equal-width figure.

  In the cross-sectional shape of the outer shape of the middle portion of the side surface portion 9, the ratio γ = Wmin / Wmax of the smallest width Wmin to the largest width Wmax seen from each direction is the height at which γ becomes the smallest among the respective heights. Also, γ> 0.994. When viewed as a whole, the side surface portion 9 can be regarded as an equal-width figure in practice. In the case of a regular pentagon, γ = 0.951. By combining the elliptic cylindrical faces to form the side face portion 9, it is possible to make the base 4 an equal-width figure and reduce the air resistance.

  The ridgeline of the side portion 9 comes to the center of the front as viewed from the front of the traveling direction, and the surface on which the opening 5 and the lid 6 are provided is on the opposite side of the traveling direction. By arranging in this manner, the air resistance can be reduced. The reason is that the wind from the front of the moving body is divided by the front ridge line, and the lid 6 does not receive the wind directly.

  FIG. 18 is a view for explaining the shape of a lid for closing the opening provided in the base of the antenna device according to the first embodiment. FIG. 18A is a view as seen from a direction perpendicular to the lid 6. FIG. 18B is a side view of the rectangular lid 6 as viewed from the direction of the side on the flange 7 side. FIG. 18C is a side view of the lid 6 as viewed from the direction perpendicular to the side on the flange 7 side. In FIG. 18 (c), the left side in the figure is the outer surface side of the lid 6. The lid 6 is an elliptic cylindrical surface whose curvature changes in the same manner on the bottom 8 side and the flange 7 side. Therefore, the lid 6 can be easily manufactured by bending a rectangular flat plate in the circumferential direction. The opening may not be rectangular, and the lid may have a shape that covers the opening. The lid can be easily manufactured by bending a flat plate having a shape closing the opening in a direction perpendicular to the axis of the elliptic cylindrical surface in accordance with the curvature of the elliptic cylindrical surface.

  The case where a base is used as a truncated cone is demonstrated as a comparative example. 19 to 24 show six views of the antenna device 50X of the comparative example. FIG. 25 to FIG. 30 show six views of the base 4X of the antenna device 50X of the comparative example. FIG. 31 shows a three-sided view for explaining the shape of the lid 6X in the comparative example. 31 (a) is a view as seen from a direction perpendicular to the lid 6X. FIG. FIG. 31 (b) is a side view of the rectangular lid 6 </ b> X as viewed from the direction of the side on the flange 7 </ b> X side. FIG. 31C is a side view of the lid 6X as viewed from the direction perpendicular to the side on the flange 7X side. In FIG. 31C, the left side in the figure is the outer surface side of the lid 6X.

  The outer shape of the base 4X is a shape in which the flange portion 7X is attached to the bottom side of the truncated cone. The bottom 8X is circular. The side surface 9X of the conical surface is provided with a rectangular opening 5X.

  The lid 6X of the comparative example is a conical surface in which the curvature on the bottom 8X side is larger than the curvature on the flange 7X side. In order to manufacture a conical surface, it is necessary to prepare a mold for forming to form a three-dimensional shape, or a process such as cutting out the shape by cutting. That is, the lid 6X of the comparative example requires more material and processing time. Therefore, the conical surface lid 6X is more expensive to manufacture than the lid of the present invention.

As a method of easily manufacturing a lid for closing the opening, it is conceivable to provide a flat portion on the side surface portion and provide an opening on the flat portion. However, providing the flat portion on the side face has the following problems.
(a) The flange portion is annular, and the shape of the connecting portion with the flange portion becomes complicated if the side surface portion is made flat.
(b) If the side face portion is a polygonal frustum, the air resistance increases. Also, the width changes depending on the viewing direction.
(c) If the side surface portion is a polygonal frustum, the enclosed space provided inside the base and the radome becomes small.

  In the present invention, since the side surface portion is formed of an elliptic cylindrical surface, not only the lid can be easily manufactured, but also the air resistance can be reduced and the internal space can be enlarged.

  In this embodiment, the side portions of the base are formed of elliptic cylinder faces having the same shape. Only the portion where the opening is provided may be an elliptic cylindrical surface, and the other may be a curved surface such as a conical surface. The side surface may be configured of a plurality of curved surfaces including at least one elliptic cylindrical surface.

  Although the bottom portion is an arc polygon generated from a regular pentagon, it is not necessary to generate an arc polygon from a regular polygon. The bottom may be an arc polygon from any polygon that is not an arc polygon or arc polygon, as long as the polygon is a polygon that is symmetrical about at least one axis of symmetry. If the traveling direction of the moving body and the axis of symmetry are parallel, air resistance can be reduced. The bottom does not have to be a Roulous polygon which is a monospaced figure. It is advantageous to make the bottom part an arc polygon having an odd number of corners in order to get closer to an equal-width figure. Although the flange portion and the bottom portion are parallel to each other, the flange portion and the bottom portion may not be parallel if there is a restriction condition of attachment to the movable body.

  In this embodiment, each of the five ellipsoidal cylinder surfaces has the same central angle, and the same inclination angle with respect to the bottom 5. Among the ellipsoidal cylinders, there may be ones having different central angles or ones having different inclination angles. In elliptic cylinder surfaces having different central angles, arc lengths in the bottom arc polygons are different. An elliptical cylindrical surface having a major axis of the same length as the diameter of a perfect circle on the flange 7 side, and an ellipse whose angle and minor axis with respect to the flange 7 are adjusted so that the cross section on the flange 7 side becomes a perfect circle Any shape may be used as long as it is a pillar surface.

  By creating an arc-shaped polygon with a bottom from an polygon with an odd number of corners, it is possible to place a ridgeline ahead of the traveling direction and an elliptical cylinder with a lid at the rear, which is advantageous in reducing air resistance. It is. In the case where the openings are provided in two planes, the ridge line can be disposed in the forward direction of the traveling direction and the lid can be disposed in the rear direction, even in the case of generating an arc-shaped polygon of the bottom from a polygon having an even number of corners.

The cross-sectional shape of the outer shape of the side surface portion on the flange portion side may be an ellipse or an arc-shaped polygon combining arcs and oval arcs. The side surface portion may be connected to the flange portion to which the radome is attached, and may be configured to have a plurality of curved surfaces including at least one elliptic cylindrical surface and have a shape that does not cause significant deterioration in air resistance. The flange portion and the bottom portion may not be parallel. When the side part is composed of a combination of elliptic cylindrical faces where the flange part and the bottom part are not parallel and the external shape on the flange side of the side part is a perfect circle and has the same central angle, the bottom part is a polygon adjacent It becomes an arc-shaped polygon that connects the corners by an elliptic arc.
The above applies to the other embodiments.

Second Embodiment
In the second embodiment, the bottom of the base of the antenna device is an arc-shaped polygon generated from an equilateral triangle. 32 to 37 show six views of the antenna device according to the second embodiment of the present invention. FIGS. 38 to 43 show six views of the base having the antenna device according to the second embodiment of the present invention. FIG. 44 is a view for explaining the shape of a lid for closing the opening provided in the base of the antenna device according to the second embodiment.

  The base 4A is a roulette polygon whose bottom 8A is an equilateral triangle. The side face portion 9A has three elliptic cylindrical faces. An opening 5A is provided in one elliptic cylindrical surface.

  FIG. 44 (a) is a view as seen from the direction perpendicular to the lid 6A. FIG. 44 (b) is a side view of the rectangular lid 6 </ b> A as viewed from the direction of the side on the flange 7 side. FIG. 44 (c) is a side view of the lid 6A as viewed from the direction perpendicular to the side on the flange 7 side. In FIG. 44 (c), the left side in the figure is the outer surface side of the lid 6A. The lid 6A is an elliptic cylindrical surface whose curvature changes in the same manner on the bottom 8A side and the flange 7 side. Therefore, the lid 6A can be easily manufactured by bending a rectangular flat plate.

  Also in the antenna device 50A of the second embodiment, the lid 6A can be easily manufactured, and the air resistance can be reduced.

Third Embodiment
The third embodiment is the case where the bottom of the base of the antenna device is an arc-shaped polygon generated from a regular heptagon. 45 to 50 show six views of the antenna device according to the third embodiment of the present invention. 51 to 56 show six views of a base having the antenna device according to the third embodiment of the present invention. FIG. 57 is a view for explaining the shape of a lid that closes the opening provided in the base of the antenna device according to the third embodiment.

  The base 4B is a loulou of which the bottom 8B is a regular heptagon. The side surface portion 9B has three elliptic cylindrical faces. An opening 5B is provided in one elliptic cylindrical surface.

  FIG. 57 (a) is a view as seen from the direction perpendicular to the lid 6B. FIG. 57 (b) is a side view of the rectangular lid 6B as viewed from the direction of the side on the flange 7 side. FIG. 57 (c) is a side view of the lid 6B as viewed from the direction perpendicular to the side on the flange 7 side. In FIG. 57 (c), the left side in the figure is the outer surface side of the lid 6B. The lid 6B is an elliptic cylindrical surface whose curvature changes in the same manner on the bottom 8B side and the flange 7 side. Therefore, the lid 6B can be easily manufactured by bending a rectangular flat plate.

  Also in the antenna device 50B of the third embodiment, the lid 6B can be easily manufactured, and the air resistance can be reduced.

  The present invention allows free combinations of the respective embodiments, or modifications or omissions of the respective embodiments within the scope of the spirit of the invention.

50, 50X, 50A, 50B Antenna Device 1 Antenna 20 Communication Device 2 Radome 3 Flange 4, 4X, 4A, 4B Base 5, 5X, 5A, 5B Opening 6, 6X, 6A, 6B Cover 7 Flange Part 8, 8X, 8A , 8B bottom 9, 9X, 9A, 9B side 10 oval cylinder

Claims (6)

With the antenna,
A radome housing the antenna;
A base having a flange portion to which the radome is attached, a bottom portion on which the antenna is mounted, and a plurality of curved side surfaces including at least one elliptic cylindrical surface connecting the flange portion and the bottom portion;
An antenna device comprising: a lid for closing an opening provided on the elliptic cylindrical surface.   The antenna device according to claim 1, wherein the cross-sectional shape of the outer shape of the side surface portion on the side of the flange portion is a true circle.   The antenna device according to claim 1, wherein the bottom portion is symmetrical with respect to at least one symmetry axis.   The antenna device according to any one of claims 1 to 3, wherein the curved surfaces are all elliptic cylindrical surfaces. The flange portion and the bottom portion are parallel;
The antenna device according to claim 4, wherein the shape of the bottom portion is a shape in which adjacent corners of a regular polygon are connected by arcs of the same radius. The antenna device is mounted on a mobile
The bottom portion is a regular polygon having an odd number of corners,
The ridgeline between the adjacent elliptic cylinder faces is ahead of the traveling direction of the movable body,
The antenna device according to claim 5, wherein the elliptic cylindrical surface having the opening and the lid is at the rearmost with respect to the traveling direction of the movable body.

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