Power divider, waveguide antenna, and method for manufacturing a power divider.

Abstract

A power dividing device for a waveguide antenna includes a plurality of hollow waveguide sections, each of which has an input hollow waveguide section capable of coupling an electromagnetic wave therein and a plurality of feed hollow waveguide sections, each of which is configured to feed an electromagnetic wave into a respective output element of the waveguide antenna for outputting the electromagnetic wave. The hollow waveguide sections each have a rectangular cross section with a narrow side and a long side. At least one branch section is provided for power division, in which one input hollow waveguide section branches into at least two output hollow waveguide sections, wherein the narrow side of the input hollow waveguide section and the narrow side of the at least two output hollow waveguide sections are at least partially different in size. The hollow waveguide sections are arranged symmetrically with respect to a plane of symmetry, which extends parallel to the narrow side of the rectangular cross section of the hollow waveguide sections.

Description

Technical Field

[0001] The present invention relates to a power splitting device for a waveguide antenna, a waveguide antenna, and a method for manufacturing a power splitting device.

Background Art

[0002] In a hollow waveguide, that is, a waveguide, electromagnetic energy is carried through a metallic hollow space. The hollow waveguide can be part of a waveguide antenna. In the simplest case, a slot is formed in the hollow waveguide, and this slot forms an interface between the internal region of the hollow waveguide and free space, that is, functions as a radiating element. This slot does not need to extend completely parallel to the flow of electromagnetic waves traveling through the hollow waveguide.

[0003] Since a single slot has only low directivity, a hollow waveguide antenna usually comprises a plurality of slots, which form an antenna array. The simplest way to form a hollow waveguide antenna array is to place slots on the long side of the rectangular cross-section of the hollow waveguide, maintaining a distance of half wavelength, so that a zigzag structure occurs relative to the center of the hollow waveguide. Due to this zigzag structure, all slots radiate in the same phase.

[0004] [[ID=二十]]When such a hollow waveguide antenna array is continuously produced in a cost-effective manner, two metal parts can be manufactured and joined later. At this time, the hollow waveguide can be arranged vertically, and the narrow side is left open for radiation. The joining of the two parts is performed parallel to the narrow side of the hollow waveguide, so the current flowing through the hollow waveguide is not obstructed. The two metal parts do not even need to have galvanic contact, and as a result, the wave guiding performance of the hollow waveguide is hardly affected.

[0005] To enable the necessary spacing between radiating elements, U.S. Patent Application Publication No. 2020 / 0203841 proposes a centrally supplied open-type hollow waveguide antenna array in which the supplying waveguide is connected to elements formed through two openings. [Overview of the Initiative]

[0006] The present invention provides a power division device for a waveguide antenna, a waveguide antenna, and a method for manufacturing the power division device, having the features of an independent patent claim.

[0007] Preferred embodiments are the subject of each dependent claim.

[0008] According to a first aspect, the present invention relates to a power division device for a waveguide antenna, comprising a plurality of hollow waveguide sections, each hollow waveguide section comprising an input hollow waveguide section capable of coupling electromagnetic waves and a plurality of supply hollow waveguide sections, each supply hollow waveguide section formed to supply electromagnetic waves to each output element of a waveguide antenna for emitting electromagnetic waves. Each hollow waveguide section has a rectangular cross-section having a narrow side and a long side. At least one branching section is provided for power division, in which one input hollow waveguide section branches into at least two output hollow waveguide sections. The hollow waveguide sections are arranged symmetrically with respect to a plane of symmetry, which extends parallel to the narrow side of the rectangular cross-section of the hollow waveguide section.

[0009] According to a second aspect, the present invention relates to a waveguide antenna comprising a plurality of emitting elements formed to emit electromagnetic waves. The waveguide antenna further comprises a power divider according to the first aspect, wherein the supply hollow waveguide portion of the power divider is formed to supply electromagnetic waves to each of the emitting elements.

[0010] According to a third aspect, the present invention relates to a method for manufacturing a power divider. In this method, a first half of the power divider is manufactured. Furthermore, a second half of the power divider is manufactured. The two halves of the power divider are connected in a plane of symmetry of the power divider.

[0011] This power divider is configured symmetrically in the vertical direction; that is, it exhibits symmetry with respect to the vertical, parallel to the longer sides of the rectangular cross-section of the hollow waveguide portion. No current flows, or only very small current flows, within the (horizontal) plane of symmetry. This allows for a simpler configuration of the power divider because a complete galvanic connection is not required within this plane of symmetry.

[0012] The power of the electromagnetic wave can be divided at least once for power division, into the output hollow waveguide section and ultimately into the supply hollow waveguide section. This allows for adjustment of the amplitude and, through the length of the hollow waveguide section, the phase of the emitted electromagnetic ray.

[0013] The emission element of a waveguide antenna can be treated as an independent element, and electromagnetic waves with the required amplitude and phase are supplied to it via a power divider. In this way, a specific amplitude distribution can be achieved at the emission element without breaking the vertical symmetry of the hollow waveguide.

[0014] Furthermore, the emitter elements can be placed very close to each other, which minimizes the side lobes in the antenna diagram.

[0015] According to a further embodiment of the power divider, the dimensions of the narrow sides of one input hollow waveguide portion and at least two output hollow waveguide portions differ from each other, at least partially.

[0016] According to a further embodiment of the power divider, the hollow waveguide portion comprises at least one hollow waveguide portion formed as a quarter-wave impedance converter. This eliminates the need to configure the width of the hollow waveguide to be very wide and enables impedance matching at at least one branch.

[0017] According to a further embodiment of the power divider, for at least one branch, the sum of the dimensions of the narrow sides of the rectangular cross-sections of at least two output hollow waveguide sections substantially matches the dimensions of the narrow sides of the rectangular cross-section of the input hollow waveguide section. This matches the impedance at the branch.

[0018] In a further embodiment of the power divider, the dimensions of the long sides of the rectangular cross-section are identical for all hollow waveguide sections. This results in a highly symmetrical configuration of the power divider.

[0019] According to a further embodiment of the power splitter, the total length from the coupling region of the input hollow waveguide portion to the supply region of the supply hollow waveguide portion differs (in empty space) by an integer multiple of half a wavelength of the electromagnetic wire. This reduces the generation of side lobes.

[0020] According to a further embodiment of the power divider, the power divider consists of two halves connected to each other in a plane of symmetry. Thus, the connection is made in the plane of symmetry, where no current or only a very low current flows. This significantly reduces the requirements for how the two halves are connected to each other. In this way, for example, a full galvanic connection between the two halves is not required, and soldering is unnecessary, making the configuration substantially less expensive. According to a further embodiment of the power divider, therefore, the connection between the two halves of the power divider is not a galvanic connection. This can be understood as having no conductive connection or at least only a very weak conductive connection.

[0021] Further advantages, features, and details of the present invention will become apparent from the following description, in which various embodiments will be described in detail with reference to the drawings.

Brief Description of the Drawings

[0022] [Figure 1] FIG. 8 is a schematic perspective view of a waveguide antenna provided with a power splitting device according to an embodiment of the present invention. [Figure 2] FIG. 11 is a further schematic perspective view of the waveguide antenna shown in FIG. 1. [Figure 3] FIG. 14 is a schematic cross-sectional view of the power splitting device of the waveguide antenna shown in FIGS. 1 and 2. [Figure 4] FIG. 17 is a schematic perspective view of the hollow waveguide portion. [Figure 5] FIG. 20 is a schematic perspective view of a branch portion for power splitting for use in a power splitting device according to an embodiment of the present invention. [Figure 6] FIG. 23 is a schematic top view of the branch portion shown in FIG. 5. [Figure 7] FIG. 26 is an equivalent circuit diagram of the branch portion shown in FIGS. 5 and 6. [Figure 8] FIG. 29 is a flowchart of a method for manufacturing a power splitting device for a waveguide antenna according to an embodiment of the present invention.

[0023] In all the figures, the same or functionally identical members and devices are denoted by the same reference numerals. The numbering of the method steps is for clarity purposes and should not generally imply a particular chronological order. In particular, a plurality of steps can also be carried out simultaneously.

Mode for Carrying Out the Invention

[0024] FIG. 1 is a schematic perspective view of a waveguide antenna 1 (i.e., a waveguide antenna array) including a power splitting device 3 and a plurality of emission elements 21 - 24 formed to emit electromagnetic waves. The emission elements 21 - 24 are formed as hollow waveguide portions that are closed on one side and open on the other side. On the open side, electromagnetic waves are emitted.

[0025] Figure 2 is a further schematic perspective view of the waveguide antenna 1 shown in Figure 1, where the outer casing is visible.

[0026] Figure 3 is a schematic cross-sectional view of the power divider 3 of the waveguide antenna shown in Figures 1 and 2. This power divider 3 comprises a plurality of hollow waveguide sections 301-312. These hollow waveguide sections 301-312 each contain an input hollow waveguide section 301 into which electromagnetic waves can be coupled or supplied. Furthermore, the power divider 3 comprises four supply hollow waveguide sections 302-305, through which electromagnetic waves are supplied to each of the emission elements 21-24, and each emission element 21-24 radiates electromagnetic waves.

[0027] In this regard, the present invention is not limited to a specific number of supply hollow waveguide sections 302-305 or output elements 21-24.

[0028] The power splitter 3 further comprises a plurality of hollow waveguide sections 306-312, which connect the input hollow waveguide section 301 to the supply hollow waveguide sections 302-305. Thus, the power splitter 3 comprises a plurality of hollow waveguide sections 301-312 as a whole, fluidly connected to one another.

[0029] Each of these hollow waveguide sections 301-312 has a rectangular cross-section with a narrow side (parallel to the horizontal XZ plane) and a long side (parallel to the vertical Y axis). The dimensions of the long side of the rectangular cross-section are the same for all hollow waveguide sections 301-312.

[0030] Multiple branching sections are provided to distribute the electromagnetic waves supplied to the input hollow waveguide section 301 to the output elements 21-24, and these function to divide the power, that is, to distribute the power of the electromagnetic waves. Each branching section comprises one input hollow waveguide section 301-312, which branches into two output hollow waveguide sections 301-312. The present invention is not limited thereto, and the input hollow waveguide section 301-312 can also branch into three or more output hollow waveguide sections 301-312.

[0031] The dimensions of the narrow sides of the input hollow waveguide section and at least two output hollow waveguide sections 301-312 differ from each other, at least partially. Preferably, impedance matching is performed at the branch, i.e., the sum of the narrow side dimensions of the output hollow waveguide sections 301-312 substantially matches the narrow side dimensions of the input hollow waveguide sections 301-312.

[0032] The hollow waveguide sections 301-312 are all arranged symmetrically with respect to a common plane of symmetry, which extends parallel to the narrow sides of the rectangular cross-sections of the hollow waveguide sections 301-312. Therefore, this plane of symmetry extends parallel to the XZ plane, passing through the center of the power divider 3.

[0033] The power divider 3 preferably consists of two halves connected to each other in a plane of symmetry. Thus, the power divider 3 consists of a lower half and an upper half, which are mirror images of each other in a plane of symmetry, but can otherwise be configured identically. These halves are preferably not galvanically connected, which simplifies manufacturing.

[0034] In the structure shown in Figure 3, the input hollow waveguide section 301 (first hollow waveguide section) having impedance Zi is first connected to the second hollow waveguide section 306, which has impedance Zti and is formed as a quarter-wave impedance converter. This second hollow waveguide section 306 branches into two output hollow waveguide sections 307 and 308 (third and fourth hollow waveguide sections, respectively). This branch corresponds to the first power divider. The impedance Z1 is the same for both of these output hollow waveguide sections 307 and 308 and is calculated as follows. Zi'=2·Z1 Zi'=Zti 2 / Zi In the formula, Zi' represents the impedance in the input hollow waveguide section 306.

[0035] The fourth hollow waveguide section 308 branches into a third supply hollow waveguide section 304 (fifth hollow waveguide section) having an impedance Z3 and a sixth hollow waveguide section 309 having an impedance Zt2. The seventh hollow waveguide section 310, having an impedance Zt3, is connected to this sixth hollow waveguide section, and in this case, the sixth hollow waveguide section 309 and the seventh hollow waveguide section 310 are formed as a quarter-wave impedance converter. The fourth supply hollow waveguide section 305 (eighth hollow waveguide section) having an impedance Z2 is connected to the seventh hollow waveguide section 310.

[0036] Symmetrically, the third hollow waveguide section 307 branches into a second supply hollow waveguide section 303 (ninth hollow waveguide section) having an impedance Z3 and a tenth hollow waveguide section 311 having an impedance Zt2. The eleventh hollow waveguide section 312, also having an impedance Zt3, is connected to this hollow waveguide section 311, and the tenth hollow waveguide section 311 and the eleventh hollow waveguide section 312 are formed as a quarter-wave impedance converter. The first supply hollow waveguide section 302 (twelfth hollow waveguide section), also having an impedance Z2, is connected to the eleventh hollow waveguide section 312.

[0037] This branching point corresponds to the second power divider, and here, Z2' = Z2·Zt2 2 / Zt3 2 Z3=2·Z2' Z1=Z3+Z2' In the equation, Z2' represents the impedance toward the 10th hollow waveguide section 311.

[0038] The length of the third hollow waveguide section 307 corresponds to half the wavelength of the electromagnetic wire, and similarly, it corresponds to the combined length of the sixth hollow waveguide section 309 and the seventh hollow waveguide section 310, and the combined length of the tenth hollow waveguide section 311 and the eleventh hollow waveguide section 312.

[0039] As a result, the phases in the supply hollow waveguide sections 302-305 are identical, and the second supply hollow waveguide section 303 and the fourth supply hollow waveguide section 305 are out of phase by 180 degrees with respect to the first supply hollow waveguide section 302 and the third supply hollow waveguide section 304. This phase shift can be compensated by coupling on the opposing sides of the emission elements 302-305, as shown in Figure 1, so that all emission elements 302-305 radiate in the same phase.

[0040] Therefore, the total length from the coupling region of the input hollow waveguide section 301 to the supply region of the supply hollow waveguide sections 302-305 differs by an integer multiple of half a wavelength of the electromagnetic wire.

[0041] By using the hollow waveguide sections 306, 309, 310, 311, and 312, which are formed as quarter-wave impedance converters, it becomes possible to achieve impedances that cannot be achieved simply by changing the dimensions of the hollow waveguide. For example, to achieve impedance Z2', impedance Z2 is a coefficient (Zt2 / Zt3) 2 It decreases by only that much. On the other hand, in order to achieve Zi', the input impedance is increased by Zti.

[0042] Figure 4 is a schematic perspective view in the XY plane of a hollow waveguide section 313 having a rectangular cross-section, where this single hollow waveguide section 313 extends along the Z axis. Here, the maximum and minimum amplitudes of electromagnetic waves in the Y direction within the hollow waveguide section 313 occur in regions 1A and 1B that are relatively outer with respect to the Y axis, i.e., in the narrow end region of the hollow waveguide. In region 1c, which includes the XZ plane passing through the center of the hollow waveguide, the amplitude in the Y direction virtually disappears. Therefore, when assembling a hollow waveguide from multiple metal parts, it is advantageous to assemble the metal parts along the XZ plane passing through the center of the hollow waveguide, because in this region, the amplitude of electromagnetic waves in the Y direction virtually disappears. The connections of the metal parts do not need to be galvanic connections.

[0043] Figure 5 is a schematic perspective view of a power splitting branch for use in the power splitter 3, which consists of a first half 3A and a second half 3B. Figure 6 is a schematic top view of the branch shown in Figure 5. The input hollow waveguide section 314 splits into two output hollow waveguide sections 315 and 316. The narrow side dimension W_in of the hollow waveguide section 314 substantially corresponds to the sum of the narrow side dimension W_1 of the first output hollow waveguide section 315 and the narrow side dimension W_2 of the second output hollow waveguide section 316. The narrow side dimensions W_1 and W_2 of both output hollow waveguide sections 315 and 316 may be different from each other, but they can also be the same size.

[0044] Figure 7 is an equivalent circuit diagram of the branching section shown in Figures 5 and 6. The power P_input of the input electromagnetic wave is divided into the power P_output_1 and power P_output_2 of the output electromagnetic wave according to the ratio of impedances Z_in, Z_1, and Z_2.

[0045] Figure 8 is a flowchart showing the method for manufacturing the power divider 3 described above for the waveguide antenna 1.

[0046] In the first method step S1, the first half 3A of the power divider 3 is manufactured.

[0047] In the second method step S2, the second half 3B of the power divider 3 is manufactured.

[0048] In the third method step S3, both halves of the power divider 3 are connected in the plane of symmetry of the power divider 3.

Claims

1. A power divider (3) for a waveguide antenna (1), The waveguide antenna (1) comprises a plurality of waveguide sections (301-316), each of which comprises an input waveguide section (301) capable of coupling electromagnetic waves and a plurality of supply waveguide sections (302-305), and each supply waveguide section (302-305) is configured to supply the electromagnetic waves to each output element (21-24) of the waveguide antenna (1) for emitting the electromagnetic waves. Each of the waveguide portions (301-316) has a rectangular cross-section with a narrow side and a long side. At least one branching section is provided for power division, and at the branching section, one input waveguide section (314) branches into at least two output waveguide sections (315, 316), The waveguide portions (301-316) are arranged symmetrically with respect to a plane of symmetry, and the plane of symmetry extends parallel to the narrow side of the rectangular cross-section of the waveguide portions (301-316). A power divider (3) wherein, for at least one branching section, the sum of the dimensions of the narrow sides of the rectangular cross-sections of at least two output waveguide sections (315, 316) substantially matches the dimension of the narrow side of the rectangular cross-section of the input waveguide section (314).

2. The power splitting device (3) according to claim 1, wherein the waveguide portion (301-316) comprises at least one waveguide portion (301-316) formed as a quarter-wave impedance converter (306-310).

3. The power splitting device (3) according to claim 1, wherein the dimensions of the long side of the rectangular cross-section are the same for all waveguide portions (301-316).

4. The power splitting device (3) according to claim 1, wherein the total length from the coupling region of the input waveguide portion (301) to the supply region of the supply waveguide portion (302-305) differs by an integer multiple of half the wavelength of the electromagnetic wave.

5. The power splitting device (3) according to claim 1, wherein the power splitting device (3) consists of two halves connected to each other in the plane of symmetry.

6. The power splitting device (3) according to claim 5, wherein the connection between the two halves of the power splitting device (3) is not a galvanic connection.

7. Waveguide antenna (1), Multiple emitting elements (21-24) configured to emit electromagnetic waves, A power splitting device (3) according to any one of claims 1 to 6, wherein each of the supply waveguide portions (302-305) of the power splitting device (3) is configured to supply the electromagnetic wave to each of the emission elements (21-24), Waveguide antenna (1).

8. A method for manufacturing a power divider (3) for a waveguide antenna (1) according to any one of claims 1 to 6, A process for manufacturing the first half of the power divider (3), A process for manufacturing the second half of the power splitting device (3), The process of connecting both halves of the power splitting device (3) on the plane of symmetry of the power splitting device (3), Methods that include...

9. The method according to claim 8, wherein both halves of the power divider (3) are connected by a non-galvanic connection.

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