阅读说明：本技术 应用于多波束天线馈电网络的定向耦合器 (Directional coupler applied to multi-beam antenna feed network ) 是由 王博琛 曾骏 汤佳龙 盛家坤 廖东 于 2019-10-25 设计创作，主要内容包括：本发明适用于通信设备技术领域,提供了一种应用于多波束天线馈电网络的定向耦合器,包括有第一微带线结构、第二微带线结构以及中层介质基板,所述第一微带线结构、所述中层介质基板以及所述第二微带线结构依次上下压合固定,所述第一微带线结构的第一耦合线置于所述中层介质基板的顶层,所述第二微带线结构的第二耦合线置于所述中层介质基板的底层。借此,本发明能够实现90度的相移,降低驻波以达到良好的传输性能,很好的应用于多波束的馈电网络中。(The invention is suitable for the technical field of communication equipment, and provides a directional coupler applied to a multi-beam antenna feed network, which comprises a first microstrip line structure, a second microstrip line structure and a middle-layer medium substrate, wherein the first microstrip line structure, the middle-layer medium substrate and the second microstrip line structure are sequentially pressed and fixed up and down, a first coupling line of the first microstrip line structure is arranged on the top layer of the middle-layer medium substrate, and a second coupling line of the second microstrip line structure is arranged on the bottom layer of the middle-layer medium substrate. Therefore, the phase shift of 90 degrees can be realized, the standing wave is reduced to achieve good transmission performance, and the phase shift filter is well applied to a multi-beam feed network.)

1. The directional coupler applied to the multi-beam antenna feed network is characterized by comprising a first microstrip line structure, a second microstrip line structure and a middle-layer medium substrate, wherein the first microstrip line structure, the middle-layer medium substrate and the second microstrip line structure are sequentially fixed in a pressing mode from top to bottom, a first coupling line of the first microstrip line structure is arranged on the top layer of the middle-layer medium substrate, and a second coupling line of the second microstrip line structure is arranged on the bottom layer of the middle-layer medium substrate.

2. The directional coupler applied to the multi-beam antenna feed network according to claim 1, wherein the first microstrip line structure comprises a first copper foil, a first dielectric substrate and the first coupling line which are sequentially stacked in layers, the second microstrip line structure comprises a second copper foil, a second dielectric substrate and the second coupling line which are sequentially stacked in layers, the first copper foil and the second copper foil are respectively arranged as an upper layer and a lower layer of the directional coupler, the first coupling line and the first copper foil and the second copper foil are connected with each other through a perforation, and the second coupling line and the first copper foil and the second copper foil are connected with each other through a perforation.

3. The directional coupler applied to the multi-beam antenna feed network according to claim 2, wherein the dielectric constant of the first dielectric substrate and the second dielectric substrate is 3.

4. The directional coupler applied to the multibeam antenna feed network of claim 1, wherein the height of the middle dielectric substrate is 0.15mm and the dielectric constant is 3.5.

5. The directional coupler applied to the multi-beam antenna feed network according to claim 1, wherein the first coupling line and the second coupling line are formed by sequentially connecting copper wires of a first port section, a first connection section, a superposition section, a second connection section and a second port section, the first port section and the second port section are perpendicular to the first connection section and the second connection section respectively in opposite directions, and the superposition section is arranged in parallel with the first connection section and the second connection section in a staggered mode; the structures of the first coupling line and the second coupling line are distributed in a mirror image mode in the vertical direction, and the overlapped sections of the first coupling line and the second coupling line are overlapped in the vertical direction.

6. The directional coupler applied to the multi-beam antenna feed network according to claim 5, wherein the line widths of the first port section, the first joining section, the second joining section, and the second port section are 1.1mm, and the line width of the coinciding section is 0.55 mm; a horizontal line distance between the first joining section of the first coupling line and the second joining section of the second coupling line is 0.16mm, and a horizontal line distance between the second joining section of the first coupling line and the first joining section of the second coupling line is 0.16 mm.

7. The directional coupler applied to the multi-beam antenna feed network according to any one of claims 1 to 6, wherein the middle dielectric substrate is provided as a PP film for hot melting to press-fit the first and second microstrip line structures.

Technical Field

The invention relates to the technical field of communication equipment, in particular to a directional coupler applied to a multi-beam antenna feed network.

Background

With the proliferation of mobile communication users, the capacity of the communication system can not meet the user requirements, and the use of the multi-beam antenna can improve the existing communication capacity, the core of the multi-beam antenna is the beam forming network thereof, which is a multi-input and multi-output feed network, the feed network can realize the switching of the wave beam, the Butler matrix (a matrix type) has simple structure and good phase characteristic, therefore, the phase shifter is often applied to a feed network of a multi-beam antenna, the Butler matrix mainly comprises a 3dB directional coupler and various phase shifters, the current 3dB directional coupler structure mainly comprises a planar structure and a multilayer structure, because the coupler with the plane structure has narrow bandwidth, the coupler can not well realize broadband coupling in engineering application, and the same polarization isolation is not high, the standing wave needs to be reduced on a multilayer structure, and the effect of 3dB coupling is achieved.

The space between the parallel coupling lines is small, and the strong coupling of the broadband is difficult to achieve, and the common solution in the industry is as follows: 1. a multi-layer multi-section coupling line structure is adopted, so that coupling is increased, and the bandwidth is increased; 2. the impedance of the odd-even mode is changed by adding a plurality of sections of additional capacitors so as to achieve the effect of impedance matching; in the multilayer board coupler, the dielectric substrate becomes a key for influencing the characteristic impedance of the odd-even mode, and generally, the same kind of dielectric substrate is adopted to enable a transmission mode to be a TEM (transverse electromagnetic wave) mode, so that standing waves are reduced and 3dB strong coupling is realized, when the dielectric substrate is not uniform, the transmission mode of a coupling line is a mixed mode, and signals can be transmitted well under the condition of realizing 3dB coupling difficultly.

As can be seen, the conventional method has many problems in practical use, and therefore, needs to be improved.

Disclosure of Invention

In view of the above drawbacks, the present invention provides a directional coupler applied to a multi-beam antenna feed network, which can achieve a 90 ° phase shift, reduce standing waves to achieve good transmission performance, and be well applied to the multi-beam antenna feed network.

In order to achieve the above object, the present invention provides a directional coupler applied to a multi-beam antenna feed network, including a first microstrip line structure, a second microstrip line structure and a middle dielectric substrate, wherein the first microstrip line structure, the middle dielectric substrate and the second microstrip line structure are sequentially fixed by pressing from top to bottom, a first coupling line of the first microstrip line structure is disposed on a top layer of the middle dielectric substrate, and a second coupling line of the second microstrip line structure is disposed on a bottom layer of the middle dielectric substrate.

According to the directional coupler applied to the multi-beam antenna feed network, the first microstrip line structure comprises a first copper foil, a first dielectric substrate and a first coupling line which are sequentially stacked in a layered manner, the second microstrip line structure comprises a second copper foil, a second dielectric substrate and a second coupling line which are sequentially stacked in a layered manner, the first copper foil and the second copper foil are respectively arranged on the upper layer and the lower layer of the directional coupler, the first coupling line is mutually connected with the first copper foil and the second copper foil through punching, and the second coupling line is mutually connected with the first copper foil and the second copper foil through punching.

According to the directional coupler applied to the multi-beam antenna feed network, the dielectric constant of the first dielectric substrate and the dielectric constant of the second dielectric substrate are 3.

According to the directional coupler applied to the multi-beam antenna feed network, the height of the middle layer dielectric substrate is 0.15mm, and the dielectric constant is 3.5.

According to the directional coupler applied to the multi-beam antenna feed network, the first coupling line and the second coupling line are formed by sequentially connecting copper wires of a first port section, a first connecting section, a superposition section, a second connecting section and a second port section, the first port section and the second port section are perpendicular to the first connecting section and the second connecting section respectively in opposite directions, and the superposition section and the first connecting section and the second connecting section are arranged in a staggered and parallel mode; the structures of the first coupling line and the second coupling line are distributed in a mirror image mode in the vertical direction, and the overlapped sections of the first coupling line and the second coupling line are overlapped in the vertical direction.

According to the directional coupler applied to the multi-beam antenna feed network, the line widths of the first port section, the first connection section, the second connection section and the second port section are 1.1mm, and the line width of the overlapped section is 0.55 mm; a horizontal line distance between the first joining section of the first coupling line and the second joining section of the second coupling line is 0.16mm, and a horizontal line distance between the second joining section of the first coupling line and the first joining section of the second coupling line is 0.16 mm.

According to the directional coupler applied to the multi-beam antenna feed network, the middle dielectric substrate is a PP (polypropylene) film for hot melting to press the first microstrip line structure and the second microstrip line structure.

The directional coupler applied to the multi-beam antenna feed network comprises a first microstrip line structure, a second microstrip line structure and a middle layer medium substrate, wherein the first microstrip line structure, the middle layer medium substrate and the second microstrip line structure are sequentially pressed and fixed up and down, a first coupling line of the first microstrip line structure is arranged on the top layer of the middle layer medium substrate, and a second coupling line of the second microstrip line structure is arranged on the bottom layer of the middle layer medium substrate. Therefore, the phase shift of 90 degrees can be realized, the standing wave is reduced to achieve good transmission performance, and the phase shift filter is well applied to a multi-beam feed network.

Drawings

Fig. 1 is an exploded view of a directional coupler applied to a multi-beam antenna feed network according to a preferred embodiment of the present invention;

fig. 2 is a plan sectional view of the first coupling line and the second coupling line of the directional coupler applied to the multi-beam antenna feeding network according to the preferred embodiment of the present invention;

fig. 3 is a schematic view of the current direction of fig. 2.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Fig. 1 shows a directional coupler applied to a multi-beam antenna feed network according to a preferred embodiment of the present invention, which includes a first microstrip line structure, a second microstrip line structure, and a middle dielectric substrate 14, wherein the first microstrip line structure, the middle dielectric substrate 14, and the second microstrip line structure are sequentially fixed by pressing from top to bottom, a first coupling line 13 of the first microstrip line structure is disposed on a top layer of the middle dielectric substrate 14, and a second coupling line 15 of the second microstrip line structure is disposed on a bottom layer of the middle dielectric substrate 14. The two microstrip line structures and a middle medium substrate 14 are pressed into the directional coupler with the three-layer plate through the process, so that the 3dB coupling under the condition of 1.695GHz-2.69GHz can be realized, and the coupler can be applied to a feed network of a multi-beam antenna with the frequency band of 1.695GHz-2.69 GHz.

The first microstrip line structure of this embodiment including the first copper foil 11 of layering superpose in proper order, first dielectric substrate 12 and first coupling line 13, the second microstrip line structure including the second copper foil 17 of layering superpose in proper order, second dielectric substrate 16 and second coupling line 15, first copper foil 11 and second copper foil 17 establish respectively the upper and lower layer of directional coupler, through punching interconnect between first coupling line 13 and first copper foil 11 and the second copper foil 17, through punching interconnect between second coupling line 15 and first copper foil 11 and the second copper foil 17. Wherein, the uppermost layer and the lowermost layer are both copper foils, namely, the ground of the coupling line, and the first coupling line 13 and the second coupling line 15 are respectively connected with the upper layer and the lower layer of the ground through punching; wherein the dielectric constant of the first dielectric substrate 12 and the second dielectric substrate 16 is 3; of course, in different embodiments, may be different dielectric constants.

Preferably, the height of the middle dielectric substrate 14 is 0.15mm, and the dielectric constant is 3.5. The middle dielectric substrate 14 of this embodiment is configured as a PP film for hot melting to press-fit the first microstrip line structure and the second microstrip line structure. Namely, the middle layer is laminated by pp films, the dielectric constant of the middle layer is 3.5, in engineering manufacture, the pp films can be melted by heating and filled to a place without circuits, the thickness is changed to be about 0.15mm, and thus a three-layer plate coupler is formed, and two coupling lines are respectively arranged on the bottom layer and the top layer of the middle layer plate.

The first coupling line 13 and the second coupling line 15 are formed by sequentially connecting copper wires of a first port section, a first connecting section, a superposition section, a second connecting section and a second port section, the first port section and the second port section are respectively perpendicular to the first connecting section and the second connecting section in opposite directions, and the superposition section and the first connecting section and the second connecting section are distributed in parallel in a staggered mode; the structures of the first coupling line 13 and the second coupling line 15 are distributed in a mirror image mode in the vertical direction, and the overlapped sections of the first coupling line 13 and the second coupling line 15 are overlapped in the vertical direction. Referring to fig. 2, the first coupled line 13 includes a first port section 110, a first splicing section 111, a superposition section 140, a second splicing section 441 and a second port section 440; the second coupled line 15 comprises a first port section 330, a first connecting section 331, a coinciding section 230, a second connecting section 221 and a second port section 220; as shown in the figure, the first port section and the second port section of the two coupling lines are distributed in opposite directions and connected with the first connecting section, the overlapping section and the second connecting section to form a Z-like shape, wherein the first connecting section and the second connecting section are positioned on a straight line, and the overlapping section is staggered and protruded on the straight line and is parallel to the first connecting section and the second connecting section; as the first microstrip line structure and the second microstrip line structure are in a vertical pressing state, that is, the first coupling line 13 and the second coupling line 15 are in a mirror image effect in a plane, as shown in the figure; the wiring structure ensures that the coupler realizes strong coupling of 3db under the condition of non-uniform medium, and can reduce standing waves and keep good isolation. Specifically, the line widths of the first port section, the first joining section, the second joining section and the second port section are 1.1mm, and the line width of the overlapping section is 0.55 mm; a horizontal line distance between the first joining section of the first coupling line and the second joining section of the second coupling line is 0.16mm, and a horizontal line distance between the second joining section of the first coupling line and the first joining section of the second coupling line is 0.16 mm.

Referring to fig. 3, a traveling wave is input from a port 1 to a port 4, an induced electromotive force is generated due to mutual inductance of an auxiliary line, an induced current is generated, the induced current is generated due to mutual capacitance, the direction is the same, the traveling wave is output from the port 2, energy is offset at the port 3 due to the opposite directions of an electric coupling current and a magnetic coupling current, the structure of the embodiment can realize that the coupling current output from the port 2 is half of the input current of the port 1, and a three-db coupling function is realized under the condition of a multilayer dielectric substrate through a compensation capacitor, because the coupler is formed by two single-layer microstrip type coupler sheets, the dielectric constant of a pp sheet is not consistent with the dielectric constant of the dielectric substrate in a single microstrip type coupler, a mixed mode is generated during transmission, and coupling and transmission performance are deteriorated, and the embodiment enables the coupler to achieve a strong coupling effect by using a layered three-section cross-, and add additional capacitance to achieve impedance matching.

Through experimental tests, standing waves of the coupler are kept below 1.22 at the working frequency of 1.695GHz-2.69GHz, and the phase shift of the through port and the coupling port of the directional coupler is 90 degrees.

In summary, the directional coupler applied to the multi-beam antenna feed network of the present invention uses the multi-layer coupled line structure, and achieves 3dB strong coupling in a wide frequency band, thereby reducing the return loss and improving the isolation. The dual-band microstrip coupler is formed by laminating two microstrip coupling lines by using a pp sheet, a strip line structure with a middle layer dielectric constant of 3.5 and upper and lower layers dielectric constants of 3.0 is formed, the wiring structure of the coupler well solves the problem of phase speed inconsistency of odd-even modes caused by uneven media, the dual-band microstrip coupler can realize 90-degree phase shift, and can be well applied to a multi-beam feed network.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it should be understood that various changes and modifications can be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.