Slider, phase shifter and base station antenna

A slider includes: a first coupling section; a second coupling section; and an impedance conversion line, which is connected between the first coupling section and the second coupling section, and includes a series portion and a parallel portion connected in series, wherein the series portion includes only one first connection line, and the parallel portion includes at least two second connection lines connected in parallel.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Chinese Patent Application No. 202011186628.7, filed Oct. 30, 2020, the entire content of which is incorporated herein by reference as if set forth fully herein.

FIELD

The present disclosure relates to the field of communication technology, and in particular, to a slider, a phase shifter, and a base station antenna.

BACKGROUND

Base station antennas typically include one or more arrays of antenna elements that are used to transmit and receive radio frequency (RF) signals. For example, a base station antenna may include a column or “linear array” of antenna elements. An RF signal may be divided into a plurality of sub-components, and the sub-components may be fed to the respective antenna elements in the linear array for transmission. The RF energy radiated by the antenna elements forms an antenna beam. Each array of antenna elements may be designed to generate antenna beams that have relatively low sidelobe levels, which acts to increase the gain of the antenna beam within a sector served by the base station antenna, and to reduce the amount of interference that the antenna beam causes in adjacent sectors and/or cells. The levels of the sidelobes of an antenna beam can be reduced by applying a relatively large magnitude taper across the antenna elements of the array, meaning that there are relatively large differences in the magnitudes of the sub-components that are fed to different antenna elements of the array. For example, with a linear array, the magnitudes of the sub-components that are fed to antenna elements in the center of the array are relatively large, and the magnitudes of the sub-components fed to other antenna elements decrease with increasing distance from the center of the linear array.

Most modern base station antennas include phase shifters that may be used to adjust the pointing direction of the antenna beams formed by the respective arrays. The phase shifters are designed to (1) split an RF signal input thereto into a plurality of sub-components and (2) applying an adjustable phase taper to the sub-components of the RF signal that are fed to the antenna elements of the array. The above-discussed phase shifters are often implemented as electromechanical phase shifters that include a moveable element such as a so-called “slider” (e.g., a wiper arm) that can be adjusted to adjust the amount of the phase shift that is applied. The slider In conjunction with a stationary component of the phase shifter) may include a power divider circuit that sub-divides an RF signal that is input to the slider into a plurality of sub-components. The slider may include a transmission line structure that is referred to as an impedance conversion line that. As the impedance of such an impedance conversion line increases, the magnitude taper that is applied to the sub-components of the RF signals increases accordingly. In general, the impedance can be adjusted by changing the line width of the impedance conversion line. However, if the line width is too narrow, it may become a source of passive intermodulation distortion, may increase the risk that some sub-components may have power levels that are too high, and may also result in manufacturing difficulties.

SUMMARY

According to a first aspect of the present disclosure, a slider is provided, and the slider includes: a first coupling section; a second coupling section; and an impedance conversion line, which is connected between the first coupling section and the second coupling section, and includes a series portion and a parallel portion connected in series, wherein, the series portion includes only one first connection line, and the parallel portion includes at least two second connection lines connected in parallel.

According to a second aspect of the present disclosure, a phase shifter is provided, and the phase shifter includes: a fixing member; and the slider as described above, which is slidably connected to the fixing member.

According to a third aspect of the present disclosure, a base station antenna is provided, and the base station antenna includes the slider as described above or the phase shifter described above.

Through the following detailed descriptions of exemplary embodiments of the present disclosure by the accompanying drawings, other features and advantages of the present disclosure will become clearer.

Note that in the embodiments described below, the same signs are sometimes used in common between different drawings to denote the same parts or parts with the same functions, and repeated descriptions thereof are omitted. In some cases, similar labels and letters are used to indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

For ease of understanding, the position, dimension, and range of each structure shown in the drawings and the like may not indicate the actual position, dimension, and range. Therefore, the present disclosure is not limited to the positions, dimensions, and ranges disclosed in the drawings and the like.

Parts shown by dotted lines in the drawings may be blocked by other parts in the viewing angles of the drawings.

DETAILED DESCRIPTION

Various exemplary embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted: unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values of components and steps set forth in these embodiments do not limit the scope of the present disclosure.

The following description of at least one exemplary embodiment is actually only illustrative, and in no way serves as any limitation to the present disclosure and its application or use. In other words, the structure and method herein are shown in an exemplary manner to illustrate different embodiments of the structure and method in the present disclosure. Those of ordinary skill in the art should understand that these examples are merely illustrative, but not in an exhaustive manner, to indicate the embodiments of the present disclosure. In addition, the drawings are not necessarily drawn to scale, and some features may be enlarged to show details of specific components.

The technologies, methods, and equipment known to those of ordinary skill in the art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be regarded as part of the specification.

In all examples shown and discussed herein, any specific value should be construed as merely exemplary value and not as limitative value. Therefore, other examples of the exemplary embodiment may have different values.

As discussed above, in a base station antenna, as shown inFIG.1, a phase shifter100may divide an RF signal input thereto into a plurality of sub-components, and may apply a phase taper across those sub-components.FIG.1illustrates a base station antenna having a phase shifter100that divides RF signals input thereto into five output sub-components, that are output at output1through output5, and applies a phase taper so that the phase difference between every two adjacent output signals in the output1, output2, output3, output4, and output5may be equal to each other. Output1, output2, output3, output4, and output5are passed to respective antenna elements200of an array (here the linear array comprising the antenna elements in the right-side column) to drive the antenna elements200to generate an antenna beam. It should be understood that in other embodiments, the phase shifter100may also convert an input signal into another number of output signals.

In order to reduce the sidelobe levels of the antenna beams generated by an array of antenna elements of the base station antenna, the amplitude of the sub-components of the RF signal that are fed to the antenna elements200that are at the ends of the linear array may be configured to be smaller than the amplitudes of the sub-components of the RF signal that are fed to the antenna elements200that are closer to the center of the linear array. In other words, the amplitudes of the sub-components of the RF signal that are output at output1and output5of the phase shifter100should be lower than the amplitudes of the sub-components of the RF signal that are output at output2, output3, and output4, so that most of the energy of the radiation signal generated by the base station antenna can be concentrated in the main lobe of the antenna beam.

A phase shifter100according to an exemplary embodiment of the present disclosure is shown inFIG.2. The phase shifter100may include a slider110and a stationary member120, where, the slider110is slidably connected to the stationary member120. When the position of the slider110relative to the stationary member120changes, the phase of each output signal output by the phase shifter100will change accordingly, which allows the downtilt angle of the antenna beam that is generated by the array of the base station antenna to be changed.

In some embodiments, the stationary member120may be a printed circuit board. As shown inFIG.2, the stationary member120may include a second substrate129, and a second connection hole129amay be provided on the second substrate129. The stationary member120may further include a first transmission line127and a second transmission line128that are provided on the second substrate129The first transmission line127and the second transmission line128may comprise, for example, microstrip transmission lines that comprise conductive traces on a first side of the second substrate129and a metal ground plane (not shown) on an opposed second side of the second substrate129. The stationary member120further includes an input port126for receiving input signals, and output ports121,122,123,124, and125for outputting output signals, wherein the output1, output2, output3, output4, and output5ofFIG.1may correspond to output ports121,122,123,124, and125, respectively. In the embodiment shown inFIG.2, output ports122and124are respectively connected to two ends of the first transmission line127, and the output ports121and125are respectively connected to two ends of the second transmission line128.

In some embodiments, the slider110may also be a printed circuit board that is configured to move relative to the stationary member120. As shown inFIG.3, the slider110may include a first substrate115. A first coupling section111, a second coupling section112, and an impedance conversion line113are provided on the first substrate115, where the impedance conversion line113is connected between the first coupling section111and the second coupling section112. The slider110may further include a connection portion114connected to the first coupling section111, and a first connection hole114amay be provided in the connection portion114. In some embodiments, the first coupling section111, the second coupling section112, the impedance conversion line113, and the connection portion114may be integrally formed by a conductive material (for example, copper) to achieve signal coupling and transmission.

As shown inFIG.2, the slider110may be slidably connected to the stationary member120by inserting a pin, rivet or the like through the first connection hole114aand the second connection hole129a. A surface of the slider110, on which the first coupling section111, the second coupling section112, the impedance conversion line113, and the connection portion114are provided, is directly opposite a surface of the stationary member120, on which the first transmission line127and the second transmission line128are provided to facilitate signal coupling. After the slider110is connected to the stationary member120, the first connection hole114ais opposite to the second connection hole129a, the first coupling section111overlaps a part of the first transmission line127, and the second coupling section112overlaps a part of the second transmission line128. As such, a signal in the phase shifter can be capacitively coupled between the first connection hole114aand the second connection hole129a, between the overlapping parts of the first coupling section111and the first transmission line127, and between the overlapping parts of the second coupling section112and the second transmission line128. The slider110can rotate around an axis passing through the first connection hole114aand the second connection hole129a. As the slider110slides relative to the stationary member120, the first coupling section111will slide along the first transmission line127and the second coupling section112will slide along the second transmission line128, thereby changing the phases of the portions of the RF signal that are coupled to the respective transmission lines127,128.

Specifically, during the operation of the phase shifter100, the input signal enters the phase shifter100at the input port126. This signal is passed to a junction where the input signal is split. A first portion of the input signal is passed to the output port123along a transmission line on the stationary member120for output, while the remainder of the input signal is capacitively coupled from the stationary member120into the slider110and is transmitted along a conductive trace on the slider110. The portion of the input signal that is coupled to the slider110is passed to the first coupling section111and the second coupling section112along the slider110. As the first coupling section111is coupled with a part of the first transmission line127on the stationary member120, a part of the signal in the slider110is coupled to the first transmission line127where it is split into two sub-components that are passed to output ports124and122, respectively. Similarly, as the second coupling section112is coupled with a part of the second transmission line128on the stationary member120, another part of the signal in the slider110is coupled to the second transmission line128where it is split into two sub-components that are passed to output ports125and121, respectively, of the stationary member120. The phase difference between each sub-component of the RF signal that is output from the phase shifter100is mainly determined by the length of the first transmission line127or the second transmission line128through which the sub-component passes. When the position of the slider110relative to the stationary member120changes, the length of the first transmission line127from the left end of the first coupling section111to the output port124, the length of the first transmission line127from the right end of the first coupling section111to the output port122, the length of the second transmission line128from the left end of the second coupling section112to the output port125, and the length of the second transmission line128from the right end of the second coupling section112to the output port121will change. As a result, the phase shift of the signal transmitted therein is changed, thereby generating output signals having different phases.

In the phase shifter100, the amplitude of the sub-component of the RF signal that is directly output through output port123is usually greater than the amplitudes of the sub-components of the RF signal that are output at output ports124and122. Due to the effect of the impedance conversion line113, the amplitudes of the sub-components of the RF signal that are output at output ports124and122are greater than the amplitudes of the sub-components of the RF signal that are output at output ports125and121. In order to increase the magnitude taper that is applied by the phase shifter100, that is, to increase the difference between the amplitudes of the sub-components of the RF signal that are output at output ports124and122and the amplitudes of the sub-components of the RF signal that are output at output ports125and121, the impedance of the impedance conversion line113connected between the first coupling section111and the second coupling section112can be increased.

In an exemplary embodiment of the present disclosure, as shown inFIG.3, the impedance conversion line113may include a series portion1131and a parallel portion1132connected in series. A single series portion1131includes only one first connection line113a, and a single parallel portion1132may include at least two second connection lines113bconnected in parallel. The arrangement of the series portion1131can help to increase the overall impedance of the impedance conversion line113to meet requirements on the magnitude taper of the phase shifter100.

To be specific, the extension dimension of the impedance conversion line113may be configured according to an operating frequency band. For example, the equivalent length of the impedance conversion line113may be equivalent to a quarter of the wavelength of the signal so as to better transmit the signal therein.

In some embodiments, the impedance conversion line113may be symmetrical or substantially symmetrical with respect to an axis passing through the midpoint of the first coupling section111and the midpoint of the second coupling section112. In other words, the phase shift introduced by the left half and the phase shift introduced by the right half of the impedance conversion line113are equal or substantially equal. When the slider110is at the center position of the stationary member120, the signal output from the output port125and the signal output from the output port121are basically in the same phase. Similarly, the signal output from the output port124and the signal output from the output port122are basically in the same phase. As the slider110deviates from the center position of the stationary member120, the phase difference between the signal output from the output port125and the signal output from the output port121becomes greater. Similarly, the phase difference between the signal output from the output port124and the signal output from the output port122becomes greater. In such a design, the phase of the signal output by each output port can be adjusted by relatively simply adjusting the position of the slider110on the fixing member120.

In the present disclosure, the series portion1131and the parallel portion1132may have a plurality of different arrangements to meet different requirements.

In an exemplary embodiment shown inFIG.3, the first connection line113aextends linearly. An end portion of the first connection line113amay be directly connected to the parallel portion1132, or directly connected to the first coupling section111or the second coupling section112.

In some embodiments, the first connection line113aor its extended line may pass through the midpoint of the first coupling section111and the midpoint of the second coupling section112to maintain symmetry.

As shown inFIG.4, in another exemplary embodiment of the present disclosure, the first connection line113amay extend in a polygonal line shape in order to further increase the impedance of the series portion113. By bending the first connection line113a, the impedance of the series portion1131can be greatly increased in a limited space, thereby effectively increasing the impedance of the impedance conversion line113.

In some embodiments, when the first connection line113aextends in a polygonal line shape, adjacent first sub-connection lines extending in different directions of the first connection line113aare chamfered and connected. In the present description, the first sub-connection line and a second sub-connection which will be described later are respectively segments extending linearly in the first connection line and the second connection line. By chamfering and connecting the adjacent first sub-connection lines, the maximum curvature in the first connection line113acan be reduced, that is, the first connection line113acan be prevented from being excessively bent. This is helpful in optimizing the passive intermodulation performance, thereby improving the signal transmission performance of the slider110.

In some embodiments, adjacent first sub-connection lines extending in different directions of the first connection line113aare perpendicular to each other. Moreover, the first sub-connection line may extend along the axis direction of the slider110or extend along a direction perpendicular to the axis to make full use of a wiring space in the slider110. Of course, in other embodiments, adjacent first sub-connection lines extending in different directions of the first connection line113amay form other angles.

In some embodiments, the first connection line113amay also extend in a curved line shape to further help to reduce the maximum curvature in the first connection line113aand improve the passive intermodulation performance, thereby improving the signal transmission performance of the slider110.

In an exemplary embodiment shown inFIG.3, the parallel portion113b[sic:1132] includes two second connection lines113bthat are connected in parallel, wherein an end portion of the second connection line113bmay be directly connected to the series portion1131or directly connected to the first coupling section111or the second coupling section112.

In other embodiments, the parallel portion113b[sic:1132] may include more that two second connection lines113bthat are connected in parallel. By changing the number of the second connection lines113bin the parallel portion113b[sic:1132] and adjusting parameters such as the line width of the first connection line113aand/or the second connection line113bin some embodiments in combination, the range of the signal amplitude that can be generated by the phase shifter100can be expanded to meet various needs.

As shown inFIG.3andFIG.4, in some embodiments, the second connection line113bmay have a polygonal line shape. In addition, adjacent second sub-connection lines extending in different directions of the second connection line113bmay be chamfered and connected to reduce the maximum curvature in the second connection line113b, that is, to avoid excessive bending of the second connection line113b. This is helpful in reducing passive intermodulation distortion. Adjacent second sub-connection lines extending in different directions of the second connection line113bmay be perpendicular to each other. Moreover, the second sub-connection line may extend along the axis direction of the slider110or extend along a direction perpendicular to the axis to make full use of the wiring space in the slider110. Of course, in some other embodiments, adjacent second sub-connection lines extending in different directions of the second connection line113bmay form other angles.

In some embodiments, for example, as shown inFIG.3, the series portion1131and the parallel portion1132are arranged alternately. In other words, a large impedance part and a small impedance part of the impedance conversion line113alternate with each other to form a step impedance, so that the amplitude of the output signal remains stable and basically does not change as the frequency changes.

Specifically, the number of bends in a single second connection line113bmay be equal to or less than 3. For example, the number of bends in the second connection line113bdirectly connected to the first coupling section111and the second coupling section112may be 3; the number of bends in the second connection line113b, with both ends being directly connected to the first connection line113a, may be 2, as shown inFIG.3andFIG.4. The aforementioned requirement can be achieved in the following manners: The second sub-connection line of the second connection line113bdirectly connected to the first coupling section111or the second coupling section112may extend along the direction of an axis passing through the midpoint of the first coupling section111and the midpoint of the second coupling section112. The second sub-connection line of the second connection line113bdirectly connected to the first connection line113amay extend along a direction perpendicular to the axis passing through the midpoint of the first coupling section111and the midpoint of the second coupling section112.

In some embodiments, the second connection line113bmay also extend in a curved line shape to further help to reduce the maximum curvature in the second connection line113band improve the passive intermodulation performance, thereby improving the signal transmission performance of the slider110.

FIG.6(a)toFIG.7(b)compare related performances of a phase shifter and a base station antenna based on the sliders ofFIG.3andFIG.5.

As shown inFIG.5, in a slider110′, an impedance conversion line113′ may include two connection lines connected in parallel. In this case, generally, the impedance of the impedance conversion line113′ is adjusted by changing the line width of the connection line. Generally, in order to ensure the performance and reliability of the phase shifter100, the line width of the connection line is 0.65 mm or greater, for example, 0.7 mm. However, in the specific example shown inFIG.5, the line width of the connection line is reduced to 0.4 mm or less to increase the impedance in order to obtain a desired magnitude taper.

FIG.6(a)andFIG.6(b)are power distribution diagrams of the output signals of each output port in a phase shifter using the sliders shown inFIG.5andFIG.3, respectively. It can be seen that by introducing the series portion1131, the difference between the signal amplitude of the outputs1and5and the signal amplitude of the outputs2and4increases, thereby increasing the magnitude taper of the phase shifter. In addition, after the series portion1131is introduced, the change of the amplitude of each output signal becomes smaller as a function of frequency, that is, the power distribution becomes flatter, which is helpful in improving the stability of the phase shifter.

FIG.7(a)andFIG.7(b)are azimuth patterns of base station antennas corresponding to the phase shifters using the sliders shown inFIG.5andFIG.3, respectively. It can be seen that by introducing the series portion1131, the sidelobe level of the radiation signal can be significantly reduced (as shown in the dashed line box), thereby improving the radiation performance of the base station antenna.

In the embodiments of the present disclosure, by providing the series portion and the parallel portion connected in series with each other in the impedance conversion line of the slider, the impedance of the impedance conversion line can be adjusted in a larger range, without relying on changing the line width to change the impedance. Therefore, the technical solutions of the present disclosure can effectively avoid problems such as decreased passive intermodulation performance, increased risk of high power, increased manufacturing difficulty and cost, and decrease in reliability caused by a line width being too small. The technical solutions of the present disclosure can adjust the impedance by changing the arrangements of the series portion and the parallel portion, and improve the flatness of the power distribution and increase the magnitude taper of the phase shifter at the same time, thereby helping to improve the radiation performance of the base station antenna.

The present disclosure further provides a base station antenna, and the base station antenna may include the slider or phase shifter described in the above embodiments.

As used herein, the words “front”, “rear”, “top”, “bottom”, “above”, “below”, etc., if present, are used for descriptive purposes and are not necessarily used to describe constant relative positions. It should be understood that the terms used in this way are interchangeable under appropriate circumstances, so that the embodiments of the present disclosure described herein, for example, can be operated on other orientations that differ from those orientations shown herein or otherwise described.

As used herein, the word “exemplary” means “serving as an example, instance, or illustration” rather than as a “model” to be copied exactly. Any realization method described exemplarily herein is not necessarily interpreted as being preferable or advantageous over other realization methods. Furthermore, the present disclosure is not limited by any expressed or implied theory given in the above technical field, background art, summary of the invention or embodiments.

As used herein, the word “basically” means including any minor changes caused by design or manufacturing defects, device or component tolerances, environmental influences, and/or other factors. The word “basically” also allows the gap from the perfect or ideal situation due to parasitic effects, noise, and other practical considerations that may be present in the actual realization.

In addition, the above description may have mentioned elements or nodes or features that are “connected” or “coupled” together. As used herein, unless specified otherwise, “connect” means that an element/node/feature is electrically, mechanically, logically connected, or connected in other manners (or communicated) with another element/node/feature. Unless explicitly stated otherwise, “coupled” means that one element/node/feature can be mechanically, electrically, logically or otherwise connected with another element/node/feature in a direct or indirect manner to allow interaction, even though the two features may not be directly connected. That is, “coupled” is intended to comprise direct and indirect connection of components or other features, including connection using one or a plurality of intermediate components.

In addition, for reference purposes only, “first”, “second” and similar terms may also be used herein, and thus are not intended to be limitative. For example, unless the context clearly indicates, the words “first”, “second” and other such numerical words involving structures or elements do not imply a sequence or order.

It should also be noted that, as used herein, the words “include”, “contain”, “have”, and any other variations indicate that the mentioned features, entireties, steps, operations, elements and/or components are present, but do not exclude the presence or addition of one or more other features, entireties, steps, operations, elements, components and/or combinations thereof.

In the present disclosure, the term “provide” is used in a broad sense to cover all ways of obtaining an object, so “providing an object” includes but is not limited to “purchase”, “preparation/manufacturing”, “arrangement/setting”, “installation/assembly”, and/or “order” of the object, etc.

Those skilled in the art should realize that the boundaries between the above operations are merely illustrative. A plurality of operations can be combined into a single operation, which may be distributed in the additional operation, and the operations can be executed at least partially overlapping in time. Also, alternative embodiments may include a plurality of instances of specific operations, and the order of operations may be changed in other various embodiments. However, other modifications, changes and substitutions are also possible. Therefore, the description and drawings hereof should be regarded as illustrative rather than restrictive.

Although some specific embodiments of the present disclosure have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration rather than for limiting the scope of the present disclosure. The embodiments disclosed herein can be combined arbitrarily without departing from the spirit and scope of the present disclosure. Those skilled in the art should also understand that various modifications can be made to the embodiments without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the attached claims.