A gradual phase shifter and a phase shift unit

Abstract

The present application provides a gradual phase shifter and a phase shifting unit, wherein the gradual phase shifter includes a network wiring board, on which an input port and multiple output ports are arranged, and the multiple output ports are connected to the input port through network wiring; the gradual phase shifter also includes a dielectric plate arranged on both sides of the network wiring board and covering the network wiring; a gradual window is arranged on the dielectric plate, and the widths of the two ends of the gradual window are unequal, and the width gradually changes from one end to the other. In actual application, when the dielectric plate moves relative to the network wiring board, the gradual window moves along the network wiring. The gradual width structure of the gradual window enables the gradual window to have the continuity of impedance transformation, so that the impedance at each level interface has good smoothness, avoiding the strong interference of electromagnetic waves caused by the large impedance transformation amplitude, thereby ensuring the stability of the output amplitude and phase of the phase shifter as much as possible, and avoiding affecting the overall coverage effect of the base station antenna.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a gradual phase shifter and a phase shift unit. Background Art

[0002] In the rapid development of communication technology, the industry has higher and higher requirements for communication quality, that is, the requirements for the construction of communication base station networks are getting higher and higher. In order to improve the communication quality of communication base stations, phase shifters are generally used in the existing technology to achieve beam downtilt and switching in base station networks. The phase shifter in the base station antenna mainly adjusts the tilt angle and side lobe of the array antenna by changing the phase of different output ports. With the continuous development of phase shifter design technology, the current mainstream phase shifter is a miniaturized dielectric phase shifter. This type of phase shifter changes the phase of each port by pulling the dielectric block in the cavity. Compared with the previous U-shaped rod phase shifter, stripline phase shifter, and fan-shaped phase shifter, it has the advantages of small size, easy assembly, and high reliability.

[0003] However, compared with the aforementioned phase shifter, the dielectric phase shifter has the problem of sudden change of the impedance of the PCB feeding network from the air section to the dielectric section. This design form of sudden change is likely to cause impedance mismatch in the feeding network, which in turn leads to the deterioration of the overall performance of the phase shifter. Therefore, in order to solve the impedance mutation problem at the interface, the current main solution is to open one or more rectangular slots on the dielectric block at the interface to form a dielectric-air window, thereby achieving impedance transition. In the process of phase shifter development, the engineering designers pay more attention to whether the return loss of the total feeding port reaches the expected value for impedance matching. When the expected value is reached, it is considered that the phase shifter is well matched. Therefore, the above-mentioned mainstream rectangular slotting method is generally used to achieve the final matching of the total feeding port impedance of the phase shifter, that is, to obtain a relatively large return loss.

[0004] Although the above-mentioned rectangular slot method can be used to design a phase shifter, a larger return loss can be obtained at the total feed port. However, there is a problem of hard impedance conversion at the air-dielectric interface, which can easily cause multiple reflections and cancellation of electromagnetic waves, thereby causing large fluctuations in amplitude and phase. Ultimately, the overall coverage effect of the base station antenna is affected due to the problem of the phase shifter.

[0005] In summary, in order to solve the problem that traditional phase shifters are prone to cause large amplitude and phase fluctuations and avoid affecting the overall coverage effect of base station antennas, it is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0006] In order to solve the problem that traditional phase shifters easily cause large fluctuations in amplitude and phase, which easily affect the overall coverage effect of base station antennas, the present application provides a gradual phase shifter and a phase shifting unit.

[0007] In a first aspect, the present application provides a gradual phase shifter, comprising a network wiring board, wherein the network wiring board is provided with an input port and a plurality of output ports, wherein the plurality of output ports are connected to the input port through network wiring;

[0008] The gradient phase shifter also includes a dielectric plate arranged on both sides of the network routing plate and covering the network routing; a gradient window is arranged on the dielectric plate, the widths of the two ends of the gradient window are not equal, and the width gradually changes from one end to the other end, and when the dielectric plate moves, the gradient window moves along the network routing.

[0009] Optionally, the number of gradient windows arranged on the same dielectric plate is two, the two gradient windows are arranged at two ends of the dielectric plate respectively, and the narrow sides of the two gradient windows are arranged opposite to each other.

[0010] Optionally, the gradient window is in a trapezoidal shape.

[0011] Optionally, the gradient window is in the shape of a triangle.

[0012] Optionally, the gradient window has a stepped shape.

[0013] Optionally, the gradient window is in the shape of a gradient line.

[0014] Optionally, the length of the gradient window is λg / 4-λg / 2, wherein λg is the wavelength of the electromagnetic wave in the medium.

[0015] Optionally, the maximum width of the gradient window is 10 mm-20 mm.

[0016] Optionally, the gradient phase shifter further includes a metal cavity, the network wiring board and the dielectric board are arranged in the metal cavity, and a feeder hole is arranged in the metal cavity.

[0017] A second aspect of the present application provides a gradual phase shifting unit, wherein the gradual phase shifting unit is arranged on a dielectric plate of a gradual phase shifter;

[0018] The gradient phase shift unit comprises a gradient window. When the dielectric plate moves, the gradient window moves along the network wiring of the gradient phase shifter.

[0019] It can be seen from the above technical solution that the present application provides a gradual phase shifter and a phase shifting unit, wherein the gradual phase shifter includes a network wiring board, on which an input port and multiple output ports are arranged, and the multiple output ports are connected to the input port through network wiring; the gradual phase shifter also includes a dielectric plate arranged on both sides of the network wiring board and covering the network wiring; a gradual window is arranged on the dielectric plate, and the widths of the two ends of the gradual window are not equal, and the width gradually changes from one end to the other end.

[0020] In actual application, when the dielectric plate moves relative to the network routing plate, the gradient window moves along the network routing. The gradient width structure of the gradient window enables the gradient window to have continuity of impedance transformation, so that the impedance at each level interface has good smoothness, avoiding the strong interference of electromagnetic waves caused by the large impedance transformation amplitude, thereby ensuring the stability of the phase shifter output amplitude and phase as much as possible, avoiding affecting the overall coverage effect of the base station antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0022] Figure 1 It is a schematic diagram of the dielectric layer and PCB structure of a simple dielectric phase shifter in the prior art;

[0023] Figure 2 for Figure 1 A schematic diagram of the structure of the impedance variation unit;

[0024] Figure 3 A schematic diagram of a structure in which two rectangular windows and one rectangular window are provided for a simple dielectric phase shifter in the prior art;

[0025] Figure 4 for Figure 1 Schematic diagram of the multi-stage impedance transformation line reflection model of the dielectric phase shifter;

[0026] Figure 5 A schematic diagram of the expanded structure of a gradual phase shifter provided in an embodiment of the present application;

[0027] Figure 6 for Figure 5 Schematic diagram of the structure of the network wiring board;

[0028] Figure 7 A schematic diagram of a gradient window structure with a trapezoidal structure provided in an embodiment of the present application;

[0029] Figure 8 A schematic diagram of a gradient window structure with a triangular structure provided in an embodiment of the present application;

[0030] Fig. 9 A schematic diagram of a gradient window structure with a stepped structure provided in an embodiment of the present application;

[0031] Fig.10 A schematic diagram of a gradient window structure with a gradient linear structure provided in an embodiment of the present application;

[0032] Fig.11 It is the reflection coefficient amplitude response curve diagram of the exponential transformation segment;

[0033] Fig.12 A schematic side view of a gradual phase shifter provided in an embodiment of the present application;

[0034] Fig.13 A schematic diagram of a metal cavity structure of a gradual phase shifter provided in an embodiment of the present application;

[0035] Fig.14 A schematic diagram of the structure of a gradual phase shifting unit provided in an embodiment of the present application.

[0036] In the figure:

[0037] 100-PCB routing layer, 200-dielectric layer, 300-impedance variation unit, 1-network routing board, 11-input port, 12-output port, 13-network routing, 2-dielectric board, 21-gradient window, 3-metal cavity, 31-feed hole. DETAILED DESCRIPTION

[0038] See also Figure 1 , which is a schematic diagram of the dielectric layer and PCB structure of a simple dielectric phase shifter in the prior art. The traditional miniaturized dielectric phase shifter is mainly divided into a metal shell, a PCB wiring layer 100, and a dielectric layer 200 distributed on the upper and lower sides of the PCB wiring layer 100. The phase of different output ports is changed by moving the dielectric layer 200 on the upper and lower sides of the PCB wiring layer 100, thereby realizing the phase shifting function.

[0039] like Figure 1 As shown, two rectangular windows are opened on the dielectric layer 200 near the air section. The purpose of such windows is to effectively transform the impedance from the air layer to the dielectric layer, and the same dielectric layer 200 contains two impedance change units 300. Existing dielectric phase shifters are all designed by opening rectangular windows in the dielectric layer. The number of windows can be one or more, but such rectangular windows have the problem of hard impedance contact, and the impedance transformation amplitude is relatively large. The electromagnetic waves on the PCB wiring layer 100 are prone to multiple transmissions and reflections at the rectangular windows. Although impedance matching is finally achieved due to interference destructiveness, the existence of interference destructiveness causes large fluctuations in the amplitude and phase of electromagnetic wave transmission in this area, which is finally reflected in each output port. Moreover, after the entire phase shifter network routing is designed, the amplitude and phase fluctuation phenomenon of the output port caused by the interference destructiveness of electromagnetic waves is difficult to analyze and solve, that is, the impedance of the feeding port is well matched, the Smith chart converges, and the standing wave ratio is relatively small, but the amplitude and phase fluctuation is large and difficult to effectively solve.

[0040] Figure 2 for Figure 1The impedance changing unit 300 in FIG. 1 is a schematic diagram of the structure of the impedance changing unit 300, which plays an important role in the impedance matching of the phase shifter. However, most existing design schemes adopt the following method: Figure 3 One rectangular window or two rectangular windows as shown, but by Figure 3 It can be seen that the use of rectangular window design will transform the impedance from Z0 in the air to Z1 in the medium, where: And ε r The value is 2.5-4, so Z0 = (1.5-2) * Z1, such as Figure 3 As shown, a schematic diagram of the structure of a simple dielectric phase shifter in the prior art is provided with two rectangular windows and one rectangular window; Figure 3 Taking (a) in the figure as an example, the impedance transformation section is Z0-Z1-Z2-Z1-Z3-Z1. Taking cost into consideration, the size of the window section is relatively limited. Therefore, the impedance transformation amplitude between each level is relatively large, and the smoothness is relatively poor.

[0041] Figure 4 for Figure 1 Schematic diagram of the multi-stage impedance transformation line reflection model of the dielectric phase shifter, composed of Figure 4 It can be seen that there is electromagnetic wave reflection at each impedance transformation interface, and finally the final reflected wave is formed at the total interface Z0. The specific reflection coefficient Γ model is as follows:

[0042]

[0043]

[0044]

[0045] Γ(θ)=Γ0+Γ1e -2j0 +Γ2e -2jθ +…+Γ N e -2jθ

[0046] Among them, θ is the electrical length of the corresponding impedance segment, e is a natural constant (about 2.718), j is an imaginary number, and N is the Nth impedance transformation segment. As can be seen from the above, the final reflected wave of the impedance change unit 300 is formed by the superposition of multiple reflected waves. Therefore, when designing the impedance transformation segment, the smoothness of the change segment will become extremely important. The traditional rectangular window design has poor impedance transformation smoothness, so the electromagnetic wave interference in this area is strong, causing large amplitude phase fluctuations, and ultimately affecting the overall coverage effect of the base station antenna due to the problem of the phase shifter.

[0047] See also Figure 5 , is a schematic diagram of the expanded structure of a gradual phase shifter provided in an embodiment of the present application.

[0048] See also Figure 6 for Figure 5 Schematic diagram of the structure of the network routing board.

[0049] In order to solve the problem that the transmission phase shifter easily causes large fluctuations in amplitude and phase, resulting in the overall coverage effect of the base station antenna, the first aspect of the embodiment of the present application provides a gradual phase shifter, including a network wiring board 1, such as Figure 6 As shown, the network wiring board 1 is provided with an input port 11 and a plurality of output ports 12, and the plurality of output ports 12 are connected to the input port 11 through a network wiring 13; Figure 5 As shown, the gradient phase shifter also includes a dielectric plate 2 arranged on both sides of the network wiring board 1 and covering the network wiring 13; a gradient window 21 is arranged on the dielectric plate 2, and the widths of the two ends of the gradient window 21 are not equal, and the width gradually changes from one end to the other end, one end has a larger width, and the other end has a smaller width, so that the width of the gradient window 21 gradually changes from one end to the other end.

[0050] In actual application, when the dielectric plate 2 moves relative to the network wiring plate 1, the gradient window 21 moves along the network wiring 13. The width gradient structure of the gradient window 21 enables the gradient window 21 to have continuity of impedance transformation, so that the impedance at each level interface has good smoothness, avoiding the strong interference of electromagnetic waves caused by the large impedance transformation amplitude, thereby ensuring the stability of the phase shifter output amplitude and phase as much as possible, avoiding affecting the overall coverage effect of the base station antenna.

[0051] Furthermore, in some embodiments of the present application, the number of gradient windows 21 provided on the same dielectric plate 2 is two, the two gradient windows 21 are respectively provided at two ends of the dielectric plate 2, and the narrow sides of the two gradient windows 21 are provided opposite to each other.

[0052] See also Figure 7 , is a schematic diagram of a gradient window structure with a trapezoidal structure provided in an embodiment of the present application.

[0053] See also Figure 8 , is a schematic diagram of a gradient window structure with a triangular structure provided in an embodiment of the present application.

[0054] See also Fig. 9 , is a schematic diagram of a gradient window structure with a stepped structure provided in an embodiment of the present application.

[0055] See also Fig.10 , is a schematic diagram of a gradient window structure of a gradient linear structure provided in an embodiment of the present application.

[0056] Further, such as Figure 7 , 8As shown in Figures 9 and 10, in some embodiments of the present application, the shape of the gradient window 21 is a trapezoid, a triangle, a step or a gradient line. The above gradient structure allows the electromagnetic wave to smoothly transition from the air into the dielectric layer, such as Fig.11 As shown, it is the reflection coefficient amplitude response curve of the exponential transformation section. The peak value |Γ| of the reflection coefficient decreases as the length of the transformation section βL increases. Therefore, in order to better match the impedance values ​​on both sides of the transformation section of the phase shift unit, the length of the gradient window 21 provided in the embodiment of the present application is λg / 4-λg / 2, where λg is the wavelength of the electromagnetic wave in the medium. The maximum width of the gradient window 21 is 10mm-20mm. The shape of the gradient window 21 is preferably a triangle or a gradient line.

[0057] See also Fig.12 , is a side view schematic diagram of a gradual phase shifter provided in an embodiment of the present application.

[0058] See also Fig.13 , is a schematic diagram of the metal cavity structure of a gradual phase shifter provided in an embodiment of the present application.

[0059] Further, such as Fig.12 As shown, in some embodiments of the present application, the gradient phase shifter also includes a metal cavity 3, the network wiring board 1 and the dielectric board 2 are arranged in the metal cavity 3, and the metal cavity 3 is provided with a feed hole 31. Among them, the input port 11 and the output port 12 are fed and welded by opening a circular feed hole 31 on the metal cavity 3. A gradient phase shifter provided in an embodiment of the present application is a one-output three-phase shifter, but is not limited to a one-output three-phase shifter, and different output ports (for example: one-output four, one-output five, one-output six, one-output seven, etc.) or phase shifters with different power distribution ratios can also be designed according to actual design needs.

[0060] A second aspect of the present application provides a gradual phase shifting unit, such as Fig.14 The figure is a schematic diagram of the structure of a gradual phase shift unit provided in an embodiment of the present application. The gradual phase shift unit is arranged on a dielectric plate 2 of a gradual phase shifter; the gradual phase shift unit comprises a gradual window 21, and when the dielectric plate 2 moves, the gradual window 21 moves along the network routing 13 of the gradual phase shifter.

[0061] It can be seen from the above technical scheme that the embodiment of the present application provides a gradual phase shifter and a phase shifting unit, wherein the gradual phase shifter includes a network wiring board 1, on which an input port 11 and multiple output ports 12 are provided, and the multiple output ports 12 are connected to the input port 11 through a network wiring 13; the gradual phase shifter also includes a dielectric plate 2 arranged on both sides of the network wiring board 1 and covering the network wiring 13; a gradual window 21 is provided on the dielectric plate 2, and the widths of the two ends of the gradual window 21 are not equal, and the width gradually changes from one end to the other end.

[0062] In actual application, when the dielectric plate 2 moves relative to the network wiring plate 1, the gradient window 21 moves along the network wiring 13. The width gradient structure of the gradient window 21 enables the gradient window 21 to have continuity of impedance transformation, so that the impedance at each level interface has good smoothness, avoiding the strong interference of electromagnetic waves caused by the large impedance transformation amplitude, thereby ensuring the stability of the phase shifter output amplitude and phase as much as possible, avoiding affecting the overall coverage effect of the base station antenna.

[0063] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. A gradual phase shifter, characterized in that: It comprises a network wiring board (1), wherein the network wiring board (1) is provided with an input port (11) and a plurality of output ports (12), wherein the plurality of output ports (12) are connected to the input port (11) via network wiring (13); The gradient phase shifter further comprises a dielectric plate (2) arranged on both sides of the network wiring board (1) and covering the network wiring (13); a gradient window (21) is arranged on the dielectric plate (2); the widths of the two ends of the gradient window (21) are unequal, and the width gradually changes from one end to the other end; when the dielectric plate (2) moves, the gradient window (21) moves along the network wiring (13).

2. The gradient phase shifter according to claim 1, characterized in that: The number of gradient windows (21) arranged on the same dielectric plate (2) is two, the two gradient windows (21) are arranged at two ends of the dielectric plate (2) respectively, and the narrow sides of the two gradient windows (21) are arranged opposite to each other.

3. The gradient phase shifter according to claim 1, characterized in that: The gradient window (21) is in the shape of a trapezoid.

4. The gradient phase shifter according to claim 1, characterized in that: The gradient window (21) is in the shape of a triangle.

5. The gradient phase shifter according to claim 1, characterized in that: The gradient window (21) is in a stepped shape.

6. The gradient phase shifter according to claim 1, characterized in that: The shape of the gradient window (21) is a gradient line.

7. The gradient phase shifter according to claim 1, characterized in that: The length of the gradient window (21) is λ g / 4-λ g / 2, where λ g is the wavelength of the electromagnetic wave in the medium.

8. The gradient phase shifter according to claim 1, characterized in that: The maximum width of the gradient window (21) is 10 mm to 20 mm.

9. The gradient phase shifter according to claim 1, characterized in that: The gradient phase shifter further comprises a metal cavity (3), the network wiring board (1) and the dielectric board (2) are arranged in the metal cavity (3), and a feeder hole (31) is arranged on the metal cavity (3).

10. A gradual phase shifting unit, characterized in that: The gradual phase shifting unit is applied to the gradual phase shifter according to any one of claims 1 to 9, and the gradual phase shifting unit is arranged on the dielectric plate (2) of the gradual phase shifter; The gradual phase shift unit comprises a gradual window (21), and when the dielectric plate (2) moves, the gradual window (21) moves along the network wiring (13) of the gradual phase shifter.

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