Waveguide antenna

Abstract

To provide a waveguide antenna that is easy to manufacture and has excellent antenna characteristics.SOLUTION: A waveguide antenna includes a waveguide 21 and a waveguide 22 having a first end and a second end, a plurality of slits 29, and a flange 219 and a flange 229. The plurality of slits 29 is formed to penetrate at least one wall surface of the waveguide 21 and the waveguide 22. The flanges 219 and 220 are formed along the outer surface of the first end on at least one surface different from the surface of the waveguide 21 in the radio wave radiation direction, and have a shape protruding outward from the outer surface.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a waveguide antenna and an antenna member used therefor. [Background technology]

[0002] A waveguide antenna is described in Patent Document 1. The waveguide antenna described in Patent Document 1 includes a rectangular waveguide.

[0003] The rectangular waveguide has multiple slits (openings) arranged along the length of the waveguide. The rectangular waveguide is fed, for example, from one end along the length. The rectangular waveguide radiates electromagnetic waves propagating within the waveguide to the outside through the multiple slits. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-53514 Summary of the Invention [Problem to be solved by the invention]

[0005] In such a waveguide antenna, in order to achieve high resolution, that is, to narrow the directivity of the radiated electromagnetic waves, it is necessary to increase the number of slits arranged.

[0006] However, the length of the rectangular waveguide in the extension direction becomes large, making it difficult to manufacture a rectangular waveguide with a uniform shape, and therefore difficult to manufacture without degrading the antenna characteristics.

[0007] SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a waveguide antenna that is easy to manufacture and has excellent antenna characteristics. [Means for solving the problem]

[0008] The antenna member of the present invention includes a rectangular waveguide having a first end and a second end, a plurality of slits for emitting radio waves, and a fixing member. The plurality of slits for emitting radio waves are formed through at least one wall surface of the rectangular waveguide. The fixing member for connection is formed along the outer surface of the first end on at least one surface of the rectangular waveguide different from the surface in the radio wave emitting direction, and has a shape that protrudes outward from the outer surface.

[0009] In this configuration, by using multiple rectangular waveguides and connecting them with fixing members, it is possible to realize a waveguide antenna that is longer than a waveguide antenna formed with a single rectangular waveguide. In this case, the fixing members are placed in a location that does not affect the radiation of the waveguide antenna, so degradation of the antenna characteristics due to the connection can be suppressed.

[0010] In the antenna member of the present invention, the fixing members are formed on multiple surfaces of the rectangular waveguide, which makes the connection between the multiple rectangular waveguides more stable.

[0011] In the antenna member of the present invention, the length (thickness) of the fixing member in the tube axis direction is longer than the wall thickness of the rectangular waveguide. With this configuration, even if stress is applied when connecting the fixing member, the effect on the rectangular waveguide can be suppressed, and deformation of the rectangular waveguide can be suppressed.

[0012] The present invention also provides a waveguide antenna including a first antenna member and a second antenna member each having any of the above-described configurations. The second antenna member has a first end and a second end opposite to those of the first antenna member. The fixing members of the first antenna member and the second antenna member are connected to each other.

[0013] In this configuration, by connecting two rectangular waveguides with their respective fixing members, a longer waveguide antenna can be realized than when a waveguide antenna is formed using only one rectangular waveguide. In this case, the fixing member is placed in a location that does not affect the radiation of the waveguide antenna, so degradation of the antenna characteristics due to the connection can be suppressed.

[0014] In the waveguide antenna of the present invention, the length of the first antenna member in the direction of the winding axis is different from the length of the second antenna member in the direction of the winding axis, and this configuration allows the connection position between the first antenna member and the second antenna member to be appropriately set at a desired position in the direction of the tube axis.

[0015] In addition, in the waveguide antenna of the present invention, the position of the connection between the first antenna member and the second antenna member in the axial direction of the tube is different from the position of the maximum point of the electric field strength of the electromagnetic waves propagating through the first antenna member and the second antenna member in the axial direction of the tube. With this configuration, the influence of the connection position between the first antenna member and the second antenna member on the radiated electromagnetic waves can be further reduced.

[0016] In addition, in the waveguide antenna of the present invention, the horn has openings that expose the fixing members of the first antenna member and the second antenna member, making it possible to check and adjust the connection state after assembling the horn.

[0017] In addition, in the waveguide antenna of the present invention, the horn has a structure in which multiple horn members are connected. The position in the axial direction of the tube where the first antenna member and the second antenna member are connected is different from the position where the multiple horn members are connected. With this configuration, the horn can be made short while maintaining the stability of the connected state.

[0018] Furthermore, the waveguide antenna of the present invention includes a reinforcing member that covers the connection positions of the plurality of horn members, which increases the shape stability of the connection portions of the plurality of horn members.

[0019] In addition, in the waveguide antenna of the present invention, the second end of the first antenna member is the feeding position for the first antenna member and the second antenna member, and a termination member is disposed at the second end of the second rectangular waveguide. With this configuration, the antenna in which the first antenna member and the second antenna member are connected can achieve more stable radio wave characteristics.

[0020] Furthermore, the waveguide antenna of the present invention includes a fixing member for connection formed along the outer surface of the second end on at least one surface of the rectangular waveguide other than the surface in the radio wave emission direction and having a shape that protrudes outward from the outer surface. With this configuration, it is easy to connect three or more antennas. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a five-view diagram of a waveguide antenna according to an embodiment of the present invention. [Figure 2] FIG. 2 is a four-sided view of an enlarged view of a waveguide antenna according to an embodiment of the present invention. [Figure 3] FIG. 3 is a cross-sectional side view of an enlarged view of a waveguide antenna according to an embodiment of the present invention. [Figure 4] FIG. 4 is a partial external perspective view of the waveguide antenna according to the embodiment of the present invention, seen from above and in front. [Figure 5] FIG. 5 is a partial external perspective view of the waveguide antenna according to the embodiment of the present invention, seen from above and behind. [Figure 6] FIG. 6 is a five-view diagram of a waveguide according to an embodiment of the present invention. [Figure 7] FIG. 7 is a partial external perspective view of a waveguide according to an embodiment of the present invention, seen from above and in front. [Figure 8] Fig. 8 is a five-view diagram of a waveguide according to an embodiment of the present invention, including a top view, a front view, a bottom view, and a back view of two combined waveguides, and a side view of one waveguide. [Figure 9] FIG. 9 is a graph showing the radiation characteristics (directivity) of the waveguide antenna according to the embodiment of the present invention. [Figure 10] FIG. 10 is a graph showing the relationship between the distribution of electric field strength in the axial direction of the waveguide and the connection position. DETAILED DESCRIPTION OF THE INVENTION

[0022] A waveguide antenna according to an embodiment of the present invention will be described with reference to the drawings.

[0023] FIG. 1 is a five-view diagram of a waveguide antenna according to an embodiment of the present invention. FIG. 1 shows a top view, a front view, a bottom view, a rear view, and a side view of the waveguide antenna. FIG. 2 shows four views of an enlarged view of a waveguide antenna according to an embodiment of the present invention. FIG. 2 shows a top view, a front view, a bottom view, and a rear view of the waveguide antenna. FIG. 3 is a side cross-sectional view of an enlarged view of a waveguide antenna according to an embodiment of the present invention. FIG. 4 is a partial external perspective view from above the front of a waveguide antenna according to an embodiment of the present invention. FIG. 5 is a partial external perspective view from above the rear of a waveguide antenna according to an embodiment of the present invention.

[0024] Fig. 6 is a five-view diagram of a waveguide according to an embodiment of the present invention. Fig. 7 is a partial external perspective view from above the front of a waveguide according to an embodiment of the present invention. Fig. 8 is a five-view diagram of a waveguide according to an embodiment of the present invention. Fig. 8 shows a top view, a front view, a bottom view, and a back view of two waveguides combined together, and a side view of one waveguide.

[0025] 1, 2, 3, 4, and 5, waveguide antenna 10 includes waveguide 21, waveguide 22, horn 30, grating 40, reinforcing member 391, and reinforcing member 392. Waveguide antenna 10 of the present invention is used in various radars, such as X-band radar and S-band radar.

[0026] (Composite waveguide structure) 1 to 8, the waveguide 21 and the waveguide 22 are rectangular waveguides made of predetermined conductors. The length L21 of the waveguide 21 in the axial direction and the length L22 of the waveguide 22 in the axial direction are different.

[0027] Waveguide 21 and waveguide 22 are arranged in this order in the tube axis direction (x-axis direction in the figure). A first end of waveguide 21 in the tube axis direction (extension direction) and a first end of waveguide 22 in the tube axis direction (extension direction) face each other and abut or nearly abut each other. In other words, waveguide 21 and waveguide 22 are connected so that the positional relationship between the first end and the second end is reversed. As a result, waveguide 21 and waveguide 22 are connected (coupled) in the tube axis direction to form a single composite waveguide having one end 20E1 and the other end 20E2.

[0028] With this configuration, the length of the composite waveguide (length L21+L22) is longer than the length of waveguide 21 alone (length L21) or the length of waveguide 22 alone (length L22). That is, a composite waveguide of a length that would be difficult to achieve with a single waveguide can be easily realized. For example, currently, when manufacturing a rectangular waveguide from aluminum, it is difficult to manufacture it with a uniform shape if it is 3 m or longer. However, by using this configuration, for example, a 5 m waveguide can be easily manufactured with a uniform shape using a 2 m waveguide and a 3 m waveguide. In particular, in the case of an antenna waveguide formed with multiple slits 29 (slots) as in the present application, the characteristics of the waveguide as a waveguide significantly affect the characteristics (directivity, etc.) of the antenna. Therefore, by using the above configuration, a composite antenna waveguide of a length that would be difficult to achieve with a single antenna waveguide can be easily realized.

[0029] A plurality of slits 29 (openings) are formed at predetermined intervals along the tube axis direction in the waveguides 21 and 22. In this case, the intervals between the plurality of slits 29 at the connection portion between the waveguides 21 and 22 are determined based on the intervals between the plurality of slits 29 in the waveguide 21 and the intervals between the plurality of slits 29 in the waveguide 22 so that the waveguide antenna 10 has a predetermined directivity.

[0030] The plurality of slits 29 are formed in the front wall 211 of the waveguide 21 and the front wall 221 of the waveguide 22. The plurality of slits 29 are formed up to predetermined ranges on the sides of the top wall 213 and the bottom wall 214 of the waveguide 21 that connect to the front wall 211, and up to predetermined ranges on the sides of the top wall 223 and the bottom wall 224 of the waveguide 22 that connect to the front wall 221.

[0031] A feeding waveguide is connected to one end 20E1 of the waveguide of the composite (the second end of waveguide 21), and a radio wave absorber (corresponding to the "termination member" of the present invention) is installed at the other end 20E2 of the waveguide of the composite (the second end of waveguide 22). That is, one end 20E1 of the waveguide of the composite becomes one end 10E1 of waveguide antenna 10, and the other end 20E2 of the waveguide of the composite becomes the other end 10E2 of waveguide antenna 10.

[0032] (Connection structure between waveguide 21 and waveguide 22) 7 and 8, in the connected state of the waveguide 21 and the waveguide 22, the front wall 211 of the waveguide 21 and the front wall 221 of the waveguide 22 are continuous in the tube axis direction, and the back wall 212 of the waveguide 21 and the back wall 222 of the waveguide 22 are continuous in the tube axis direction. In addition, the top wall 213 of the waveguide 21 and the top wall 223 of the waveguide 22 are continuous in the tube axis direction, and the bottom wall 214 of the waveguide 21 and the bottom wall 224 of the waveguide 22 are continuous in the tube axis direction.

[0033] Flange 219 is made of a flat plate and is fixed to the first end of waveguide 21. For example, flange 219 is welded to the first end of waveguide 21. Flange 219 corresponds to the "fixing member" of the present invention. The composite of waveguide 21 and flange 219 corresponds to the "first antenna member" of the present invention.

[0034] The flat surface of flange 219 is perpendicular to the axial direction of waveguide 21. One of the flat surfaces of flange 219 is flush with the opening surface of the first end of waveguide 21.

[0035] The flange 219 is C-shaped when viewed in a direction perpendicular to the flat plate surface (a direction perpendicular to the tube axis direction of the waveguide 21). The flange 219 is fixed to the outer surfaces of the top wall 213, rear wall 212, and bottom wall 214 of the waveguide 21. In this case, the flange 219 has a shape that does not reach the front wall 211 of the waveguide 21. More specifically, the flange 219 has a shape that does not reach a slit formation region (ReSL) in which a plurality of slits 29 are formed in the top wall 213 and bottom wall 214 of the waveguide 21 in the width direction (y-axis direction) of the waveguide 21.

[0036] The thickness D of the flange 219 is greater than the wall thickness D200 of the waveguide 21.

[0037] Flange 229 is made of a flat plate and is fixed to the first end of waveguide 22. For example, flange 229 is welded to the first end of waveguide 22. Flange 229 has the same structure as flange 219. Flange 229 corresponds to the "fixing member" of the present invention. The composite of waveguide 22 and flange 229 corresponds to the "second antenna member" of the present invention.

[0038] The flat surface of flange 229 is perpendicular to the axial direction of waveguide 22. One of the flat surfaces of flange 229 is flush with the opening surface of the first end of waveguide 22.

[0039] The flange 229 is C-shaped when viewed in a direction perpendicular to the flat plate surface (a direction perpendicular to the tube axis direction of the waveguide 22). The flange 229 is fixed to the outer surfaces of the top wall 223, rear wall 222, and bottom wall 224 of the waveguide 22. In this case, the flange 229 has a shape that does not reach the front wall 221 of the waveguide 22. More specifically, the flange 229 has a shape that does not reach a slit formation region ReSL in the width direction (y-axis direction) of the waveguide 22, where a plurality of slits 29 are formed in the top wall 223 and bottom wall 224 of the waveguide 22.

[0040] The thickness D of the flange 229 is greater than the wall thickness D200 of the waveguide 22.

[0041] The flanges 219 and 229 are disposed close to or in contact with each other so that their flat surfaces face each other. The flanges 219 and 229 are fixed to each other with screws or the like.

[0042] As a result, the waveguide 21 and the waveguide 22 are fixed so that their relative positions do not change.

[0043] Furthermore, by using flanges 219 and 229, it is not necessary to connect (join) the connecting portion between waveguide 21 and waveguide 22 by direct welding or the like. This makes it possible to suppress deformation of the connecting portion between waveguide 21 and waveguide 22 (for example, deformation due to heat of welding or the like). Therefore, it is possible to suppress deterioration of the propagation characteristics of the composite waveguide and the radiation characteristics (antenna characteristics) of waveguide antenna 10.

[0044] Furthermore, flanges 219 and 229 are formed at positions that do not come into contact with slit formation regions ReSL of the multiple slits 29 in the waveguide of the composite, thereby not affecting the front side shape of waveguide antenna 10. Therefore, deterioration of the radiation characteristics (antenna characteristics) of waveguide antenna 10 can be suppressed.

[0045] Furthermore, flanges 219 and 229 are thicker than waveguide 21 and waveguide 22. This makes it possible to suppress deformation of flanges 219 and 229, waveguide 21, and waveguide 22 when flanges 219 and 229 are fixed with screws. This makes it possible to suppress deterioration of the propagation characteristics of the composite waveguide and the radiation characteristics (antenna characteristics) of waveguide antenna 10.

[0046] Furthermore, flanges 219 and 229 are fixed to three surfaces of waveguide 21 and waveguide 22. This allows the positional relationship between waveguide 21 and waveguide 22 to be fixed by flanges 219 and 229 that extend across the three surfaces. Therefore, the fixed state between waveguide 21 and waveguide 22 is stable, and deterioration of the propagation characteristics of the composite waveguide and the radiation characteristics (antenna characteristics) of waveguide antenna 10 can be suppressed.

[0047] Furthermore, flanges 219 and 229 are fixed to each other with screws on both the top and bottom sides of waveguides 21 and 22. Therefore, the fixed state of waveguides 21 and 22 is stable, and deterioration of the propagation characteristics of the composite waveguide and the radiation characteristics (antenna characteristics) of waveguide antenna 10 can be suppressed.

[0048] It is preferable that flanges 219 and 229 are fixed flush, but they may be approximately flush. In the case of approximately flush, it is only necessary to avoid a state in which electromagnetic waves leak from gaps that may occur during manufacturing at the connection between waveguide 21 and waveguide 22 when flanges 219 and 229 are fixed with screws or the like, thereby adversely affecting the characteristics of the antenna (a state in which the desired characteristics cannot be obtained).

[0049] This also includes a state in which a gap is formed at the connection between waveguide 21 and waveguide 22 for reasons different from the fixed state between flange 219 and flange 229. In other words, it is preferable that there is no gap at the connection between waveguide 21 and waveguide 22. However, even if a gap is present, it is sufficient as long as it does not adversely affect the characteristics of the antenna (a state in which desired characteristics cannot be obtained).

[0050] (Structure other than the waveguide of the composite in the waveguide antenna 10) For the composite waveguide having the above-described structure, horn 30, grating 40, reinforcing member 391, and reinforcing member 392 are installed as follows.

[0051] Horn 30 is installed on the front side of the composite waveguide. Horn 30 is composed of upper horns 311 and 321 and lower horns 312 and 322. Upper horns 311 and 321 and lower horns 312 and 322 are plate-shaped conductors.

[0052] The widths of the upper horns 311, 321 and the lower horns 312, 322 (the lengths along the tube axis direction of the waveguide of the composite (length in the x-axis direction)) are shorter than the length L21 in the tube axis direction of the waveguide 21 and longer than the length L22 in the tube axis direction of the waveguide 22. As a specific example, the widths of the upper horns 311, 321 and the lower horns 312, 322 are approximately half the length (L21 + L22) in the tube axis direction of the waveguide of the composite.

[0053] Upper horn 311 is arranged on the top wall 213 side of waveguide 21 and is fixed to waveguide 21. Lower horn 312 is arranged on the bottom wall 214 side of waveguide 21 and is fixed to waveguide 21. Upper horn 311 and lower horn 312 are arranged opposite each other with waveguide 21 in between. Upper horn 311 and lower horn 312 form a first horn 31.

[0054] Upper horn 321 is arranged on the top wall 223 side of waveguide 22 and on the top wall 213 side of part of waveguide 21, and is fixed to waveguide 22 and waveguide 21. Lower horn 322 is arranged on the bottom wall 224 side of waveguide 22 and on the bottom wall 214 side of waveguide 21, and is fixed to waveguide 22 and waveguide 21. Upper horn 321 and lower horn 322 are arranged opposite each other with waveguide 22 and part of waveguide 21 in between. Upper horn 321 and lower horn 322 form a second horn 32.

[0055] In this case, in the axial direction of the waveguide of the composite, the position of the connection between upper horn 311 and upper horn 321 and the position of the connection between lower horn 312 and lower horn 322 are different from the connection between waveguide 21 and waveguide 22. In other words, the connection between waveguide 21 and waveguide 22 is different from center position C10 of waveguide antenna 10 in the axial direction.

[0056] Then, upper horn 321 and lower horn 322 constituting second horn 32 cover and sandwich the connection portion between waveguide 21 and waveguide 22. In this state, upper horn 321 and lower horn 322 are fixed to waveguide 21 and waveguide 22.

[0057] With this configuration, the connection between waveguide 21 and waveguide 22 is also fixed by second horn 32. Therefore, the connection between waveguide 21 and waveguide 22 becomes more stable.

[0058] It is more preferable that upper horn 321 and lower horn 322 further secure the connection between waveguide 21 and waveguide 22 from the rear side of waveguide 21 and waveguide 22 .

[0059] Reinforcing member 391 is placed and fixed on the upper surfaces (surfaces of the composite opposite to the surface facing the waveguide) of upper horn 311 and upper horn 321. In this case, reinforcing member 391 covers the connection portion between upper horn 311 and upper horn 321.

[0060] This enables reinforcing member 391 to more stably fix upper horn 311 and upper horn 321. Furthermore, by stably fixing upper horn 311 and upper horn 321, the connection state between waveguide 21 and waveguide 22 becomes even more stable.

[0061] Reinforcing member 392 is disposed on and fixed to the lower surfaces of lower horn 312 and lower horn 322 (surfaces of the composite opposite to the surface facing the waveguide). In this case, reinforcing member 392 covers the connection portion between lower horn 312 and lower horn 322. This enables reinforcing member 392 to fix lower horn 312 and lower horn 322 more stably.

[0062] This enables reinforcing member 392 to more stably fix lower horn 312 and lower horn 322. Furthermore, by stably fixing lower horn 312 and lower horn 322, the connection between waveguide 21 and waveguide 22 becomes even more stable.

[0063] Upper horn 321 has opening 3210, and lower horn 322 has opening 3220. Reinforcing member 392 has opening 3920. Flanges 319 and 329 are inserted through openings 3210, 3220, and 3920, respectively, and are exposed to the outside.

[0064] This allows the radar manufacturer, engineer, etc. to check the fixed state by the flanges 319 and 329 and adjust the fixed state.

[0065] Grating 40 is placed on the front side of the composite waveguides (waveguide 21 and waveguide 22). Grating 40 is placed at a predetermined distance from the front surface of the composite waveguides. The shape of the space surrounded by grating 40, the front wall of the composite waveguides, and horn 30 is set based on the directivity of waveguide antenna 10.

[0066] In this configuration, flanges 319 and 329 do not affect the shape of the space surrounded by grating 40, the front wall of the composite waveguide, and horn 30. As a result, even when a composite waveguide using flanges 319 and 329 is used, deterioration of characteristics such as the directivity of waveguide antenna 10 can be suppressed.

[0067] With the above configuration, the waveguide antenna 10 can easily realize a long antenna, which has been difficult to manufacture in the past. As a result, the waveguide antenna 10 can more easily realize a narrow directivity antenna. In other words, the waveguide antenna 10 can be easily manufactured and achieve excellent antenna characteristics.

[0068] 9 is a graph showing the radiation characteristics (directivity) of the waveguide antenna according to the embodiment of the present invention. As shown in FIG. 9, the waveguide antenna 10 can achieve antenna characteristics with narrow directivity.

[0069] In this case, waveguide antenna 10 has feed port 19 at the center of waveguide antenna 10 in the tube axial direction, and is fed from one end 10E1 by a feeding waveguide. Waveguide antenna 10 forms a radio wave transmission line on the bottom side of waveguide 21, and feeds power to the composite waveguide from one end 10E1 of waveguide antenna 10 (one end 20E1 of the composite waveguide). With this configuration, the electromagnetic field distribution of the waveguide can be more stably achieved as desired, compared to feeding power from the center of the waveguide in the tube axial direction. Even with this feeding mode, the configuration of waveguide antenna 10 allows desired characteristics to be achieved. This allows waveguide antenna 10 to achieve even better antenna characteristics.

[0070] Furthermore, the above-mentioned connection position between the waveguide 21 and the waveguide 22 in the tube axis direction is one example, and other positions are also possible.

[0071] Fig. 10 is a graph showing the relationship between the distribution of electric field strength in the waveguide axial direction and the connection position. As shown in Fig. 10, the connection position between waveguide 21 and waveguide 22 is different from the position where the electric field strength is maximum. This reduces the influence of the connection between waveguide 21 and waveguide 22 on the electric field inside the waveguide. However, if the desired antenna characteristics can be achieved, the connection position between waveguide 21 and waveguide 22 may be the same as the position where the electric field strength is maximum.

[0072] It is preferable that the distance between the connection position of waveguide 21 and waveguide 22 and the position where the electric field strength is maximum is long. In other words, it is preferable that the connection position of waveguide 21 and waveguide 22 is a position where the electric field strength is low. Therefore, the connection position of waveguide 21 and waveguide 22 (the length of waveguide 21 and waveguide 22) can be determined taking into consideration the length that makes it easy to manufacture waveguide 21 and waveguide 22 and the electric field strength.

[0073] Although the above description shows an embodiment using two waveguides, three or more may be used. In this case, at least the intermediate waveguides in the order of coupling need to have flanges on both the first and second ends. This allows for a longer waveguide antenna to be realized.

[0074] In the above description, flange 219 and flange 329 are fixed to three surfaces of the waveguide. However, flange 219 and flange 329 may have a shape that allows them to be fixed to at least one surface of the waveguide. For example, flange 219 is formed and fixed only to the outer surface of top wall 213 of waveguide 21. Flange 229 is formed and fixed only to the outer surface of top wall 223 of waveguide 22. However, it is preferable that flange 219 and flange 329 have as many surfaces to which they are fixed as possible. [Explanation of symbols]

[0075] 10: Waveguide antenna 21, 22: Waveguide 29: Slit 30: Horn 31: First Horn 32: Second Horn 40: Lattice 211, 221: Front wall 212, 222: Back wall 213, 223: Top wall 214, 224: Bottom wall 219, 229: Flanges 311, 321: Upper horn 312, 322: Lower horn 391, 392: Reinforcing members

Claims

1. a rectangular waveguide having a first end and a second end; a plurality of slits for emitting radio waves formed through at least one wall surface of the rectangular waveguide; a fixing member for connection formed along an outer surface of the first end on at least one surface of the rectangular waveguide different from the surface in the radio wave emission direction, the fixing member having a shape that protrudes outward from the outer surface; a first antenna member comprising: a second antenna member including a rectangular waveguide, a plurality of slits, and a fixing member for connection, similar to the first antenna member, and having a first end and a second end opposite in position to the first antenna member; Equipped with The length of the first antenna member in the tube axis direction is different from the length of the second antenna member in the tube axis direction. Waveguide antenna.

2. a rectangular waveguide having a first end and a second end; a plurality of slits for emitting radio waves formed through at least one wall surface of the rectangular waveguide; a fixing member for connection formed along an outer surface of the first end on at least one surface of the rectangular waveguide different from the surface in the radio wave emission direction, the fixing member having a shape that protrudes outward from the outer surface; a first antenna member comprising: a second antenna member including a rectangular waveguide, a plurality of slits, and a fixing member for connection, similar to the first antenna member, and having a first end and a second end opposite in position to the first antenna member; Equipped with a position in the tube axis direction where the first antenna member and the second antenna member are connected and a position where the electric field strength of the electromagnetic wave propagating through the first antenna member and the second antenna member is maximum are different; Waveguide antenna.

3. a rectangular waveguide having a first end and a second end; a plurality of slits for emitting radio waves formed through at least one wall surface of the rectangular waveguide; a fixing member for connection formed along an outer surface of the first end on at least one surface of the rectangular waveguide different from the surface in the radio wave emission direction, the fixing member having a shape that protrudes outward from the outer surface; a first antenna member comprising: a second antenna member including a rectangular waveguide, a plurality of slits, and a fixing member for connection, similar to the first antenna member, and having a first end and a second end opposite in position to the first antenna member; Equipped with power is fed to the first antenna member and the second antenna member from a second end of the rectangular waveguide in the first antenna member; a termination member is disposed at a second end of the rectangular waveguide of the second antenna member; Waveguide antenna.

4. 4. The waveguide antenna according to claim 1, The fixing members are formed on multiple surfaces of the rectangular waveguide. Waveguide antenna.

5. 5. The waveguide antenna according to claim 1, The length of the fixing member in the tube axis direction is longer than the thickness of the face wall of the rectangular waveguide. Waveguide antenna.

6. 6. A waveguide antenna according to claim 1, The fixing member has an opening in the tube axis direction. Waveguide antenna.

7. 3. The waveguide antenna according to claim 2, a horn having an opening for exposing the fixing members of the first antenna member and the second antenna member, Waveguide antenna.

8. 8. The waveguide antenna of claim 7, The horn has a structure in which a plurality of horn members are connected together, a position where the first antenna member and the second antenna member are connected in the tube axis direction is different from a position where the plurality of horn members are connected; Waveguide antenna.

9. 9. A waveguide antenna according to claim 8, a reinforcing member covering the connection positions of the plurality of horn members; Waveguide antenna.

10. The waveguide antenna according to claim 1 or claim 2, power is fed to the first antenna member and the second antenna member from a second end of the rectangular waveguide in the first antenna member; a termination member is disposed at a second end of the rectangular waveguide of the second antenna member; Waveguide antenna.

11. 11. A waveguide antenna according to any one of claims 1 to 10, a connecting fixing member formed along an outer surface of the second end on at least one surface of the rectangular waveguide different from the surface in the radio wave emission direction and having a shape that protrudes outward from the outer surface; Waveguide antenna.

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