A scattering suppression structure and an antenna unit using the same

Abstract

The application provides a scattering suppression structure and an antenna unit using the same. The scattering suppression structure comprises: a slot loop structure comprising: a peripheral closed conductor, an inner closed conductor, and a slot loop formed between the peripheral closed conductor and the inner closed conductor; an LC equivalent loading structure comprising: a parallelly connected capacitance equivalent structure and an inductance equivalent structure; and the slot loop structure and the LC equivalent loading structure are cascaded to form the scattering suppression structure. The scattering suppression structure provided by the embodiment of the application connects the slot loop structure with the LC equivalent loading structure having a specific frequency response characteristic, and reduces the interference of the scattering field while keeping the frequency response characteristic unchanged.

Description

Technical Field

[0001] This invention relates to the field of base station antenna technology, and more specifically to a scattering suppression structure and an antenna element using the structure. Background Technology

[0002] With the development of mobile communication systems, site resources are becoming increasingly scarce. To meet operators' requirements for antenna size, multi-band antennas must be used and made as small as possible. Against this backdrop, multi-band common aperture technology has attracted widespread attention in the industry. By arranging antenna elements of different frequency bands with a common aperture, the size of antenna products can be significantly reduced. However, according to electromagnetic theory, the method of simply arranging high- and low-frequency antenna elements close together to achieve a common aperture suffers from inter-element scattering interference. Among these, the low-frequency antenna elements, due to their larger size, are particularly susceptible to scattering interference from the high-frequency band.

[0003] To overcome this problem, existing technologies embed a loading structure with high-frequency choke characteristics (referred to as "loading technology") into the antenna element to reduce the scattering signal of the original, longer antenna element that generates strong scattering signals. However, when the unloaded initial antenna is embedded with a loading structure with high-frequency choke characteristics, although it is divided into several smaller local conductors, which can reduce scattering interference to a certain extent, a scattering field will still be generated, and the interference of the scattering field cannot be completely eliminated. By using frequency selective units with high-frequency pass and low-frequency block (referred to as "frequency selective unit technology") to splice and combine them, an antenna element with a new shape is formed. Since multiple frequency selective units are directly cascaded, a new shape profile will appear, and the frequency selective units connected to the shape profile line (directly connected or coupled) are not isolated from each other. Therefore, the new shape profile will generate new frequency response characteristics, which will have an unwanted impact on the original frequency selective characteristics, resulting in a decrease in the stopband resonant frequency and a deterioration in the passband performance. Summary of the Invention

[0004] In view of this, the present invention provides a scattering suppression structure and an antenna unit using the structure, which solves the above-mentioned problems existing in the prior art and further improves the scattering suppression effect in principle.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, embodiments of the present invention provide a scattering suppression structure, comprising:

[0007] The gap loop structure includes: an outer closed conductor, an inner closed conductor, and a gap loop formed between the outer closed conductor and the inner closed conductor;

[0008] LC equivalent loading structure, including: a capacitor equivalent structure and an inductor equivalent structure connected in parallel;

[0009] The cascaded gap loop structure and the LC equivalent loading structure form a scattering suppression structure.

[0010] The scattering suppression structure provided in this embodiment of the invention uses an LC equivalent loading structure with specific frequency response characteristics to connect the gap loop structure, thereby reducing the interference of the scattered field while maintaining the frequency response characteristics unchanged.

[0011] Optionally, the length of the slot loop is equal to the operating wavelength corresponding to any frequency in the high-frequency band of the high- and low-frequency common-aperture antenna element.

[0012] According to electromagnetic theory, the method of arranging high- and low-frequency antenna elements close together to achieve a common aperture results in scattering interference between elements. Among them, the low-frequency antenna elements are larger in size, and the scattering interference to the high-frequency band is particularly severe. Setting the length of the slot loop to be equal to the operating wavelength corresponding to any frequency in the high-frequency band of the high- and low-frequency common aperture antenna elements is beneficial to reducing the scattering interference to the high-frequency band.

[0013] Optionally, both the outer conductor and the inner conductor are of uniform width and form a closed strip circuit.

[0014] A closed or equivalent closed loop has bandpass characteristics. The scattering suppression structure mainly utilizes the bandpass characteristics to achieve bandpass in the high-frequency band and adjacent frequency bands. The outer conductor and inner conductor are set to have uniform width to form a closed strip line, which is convenient for design and production, simplifies production difficulty, and saves manpower and material resources.

[0015] Optionally, the width of the inner conductor is greater than the width of the outer conductor.

[0016] Optionally, the inner conductor is a solid conductive pattern.

[0017] The width of the conductor is a variable design parameter. The width of the inner conductor is greater than that of the outer conductor, which can increase the frequency response bandwidth and resist manufacturing errors. In extreme cases, the inner conductor is a solid conductive pattern.

[0018] Optionally, the design principle of the LC equivalent loading structure is the equivalent principle of the LC parallel loading circuit.

[0019] Optionally, the equivalent capacitance structure and the equivalent inductance structure in the LC equivalent loading structure are located on both sides of the two parallel nodes; or the equivalent capacitance structure and the equivalent inductance structure are located on the same side of the two parallel nodes, and the equivalent capacitance structure is located inside the equivalent inductance structure.

[0020] The frequency characteristics of an LC parallel loading circuit are determined by the parameters of the capacitor and the inductor. When the parameters of the capacitor and the inductor are matched, the circuit exhibits resonance characteristics. The LC equivalent loading structure designed using this principle ensures the scattering characteristics within the operating frequency band.

[0021] Secondly, embodiments of the present invention provide an electromagnetic boundary, including an isolation sheet, wherein the isolation sheet is provided with a scattering suppression structure as described in any one of the first aspects.

[0022] Thirdly, embodiments of the present invention provide a low-frequency radiation unit, including a radiation arm, wherein the radiation arm is provided with a scattering suppression structure as described in any one of the first aspects.

[0023] Fourthly, embodiments of the present invention provide an antenna element, the antenna element comprising:

[0024] The scattering suppression structure as described in any of the first aspects, the electromagnetic boundary as described in the second aspect, or the low-frequency radiation unit as described in the third aspect.

[0025] The antenna unit provided in this embodiment of the invention utilizes the scattering suppression structure described in the first aspect, which can better suppress scattering suppression induced current. It can be set on the isolator at the electromagnetic boundary or used on the radiating arm of the radiating unit. Using the isolator or radiating arm with the scattering suppression structure to design the antenna can improve the performance indicators of the multi-frequency antenna, and make debugging easier, facilitate design optimization, and have a simpler structure and stronger versatility. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of a scattering suppression structure provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the gap loop structure in a scattering suppression structure provided in an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of a slit loop structure in a specific embodiment of a scattering suppression structure provided by the present invention;

[0030] Figure 4 This is a schematic diagram of a prior art structure in which multiple frequency selection units are directly cascaded, as provided in an embodiment of the present invention.

[0031] Figure 5The graphs show the plane wave transmission performance in three cases: a single slit loop structure, a direct cascade of single slit loop structures, and a cascade of single slit loop structures through an LC equivalent loading structure, provided in the embodiments of the present invention.

[0032] Figure 6 A schematic diagram of the equivalent principle structure of an LC parallel circuit provided in an embodiment of the present invention;

[0033] Figure 7 This is a schematic diagram of the LC equivalent loading structure in a specific embodiment of the present invention;

[0034] Figure 8 This is a schematic diagram of the LC equivalent loading structure in another specific embodiment of the present invention;

[0035] Figure 9 This is a schematic diagram of the cascaded LC equivalent loading structure and gap loop structure in a specific embodiment of the present invention.

[0036] Figure 10 This is a schematic diagram illustrating the application of a combination of a slotted loop structure and an LC equivalent loading structure to a "loop" antenna element, as provided in an embodiment of the present invention.

[0037] Figure 11 This is a schematic diagram illustrating the application of a combination of a slotted loop structure and an LC equivalent loading structure to a "linear" antenna element, as provided in an embodiment of the present invention.

[0038] Figure 12 This is a schematic diagram illustrating the application of a combination of a slotted loop structure and an LC equivalent loading structure to a "monopole" antenna element, as provided in an embodiment of the present invention.

[0039] Figure 13 The diagram shows the slit loop structure provided in the embodiment of the present invention, which is implemented using an elliptical slit loop, combined with an LC equivalent loading structure, and then applied to a "linear" radiating unit. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can also refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0043] The technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] Example 1

[0045] This invention provides a scattering suppression structure, such as... Figure 1 As shown, it includes: a slit loop structure 1 and an LC equivalent loading structure 2, which are cascaded to form a scattering suppression structure.

[0046] like Figure 2 As shown, the slot loop structure 1 includes: an outer closed conductor 11, an inner closed conductor 12, and a slot loop 13 formed between the outer and inner closed conductors. Exemplarily, the slot loop structure is a commonly used frequency selection unit. In this embodiment, it can also be used to replace the slot loop structure with multiple other types of frequency selection units, allowing the cascaded frequency selection units to better maintain their original characteristics. Furthermore, more design freedom can be obtained by changing the characteristics of individual frequency selection units.

[0047] Specifically, in one embodiment, the length of the slot loop is equal to the operating wavelength corresponding to any frequency in the high-frequency band of the high- and low-frequency common-aperture antenna element. For example, first, the frequency ranges of the low-frequency and high-frequency bands of the high- and low-frequency common-aperture antenna element are determined, and the operating wavelength corresponding to any frequency in the high-frequency band is calculated, denoted as "Lh". The length of the slot loop (e.g., ...) is then set to the operating wavelength of any frequency in the high-frequency band. Figure 2The dashed line shown is equal to "Lh", serving as the initial value for the slot loop length. It should be noted that during the design process, the optimal slot loop length can be obtained by fine-tuning the slot width and the dielectric parameters of the attached medium. According to electromagnetic theory, simply arranging high- and low-frequency antenna elements close together to achieve a common aperture results in scattering interference between elements. The low-frequency antenna elements, due to their larger size, cause particularly severe scattering interference in the high-frequency band. Setting the slot loop length to be equal to the operating wavelength corresponding to any frequency in the high-frequency band of the high- and low-frequency common-aperture antenna elements helps reduce scattering interference in the high-frequency band.

[0048] Specifically, in one embodiment, both the outer conductor and the inner conductor are of uniform width, forming a closed strip-shaped circuit. Exemplarily, the width and shape of the outer and inner conductors of the slot loop structure can be flexibly adjusted. This embodiment uses a rectangular shape as an example, but it is not limited to this; it can also be circular. A closed or equivalently closed loop has bandpass characteristics. The scattering suppression structure mainly utilizes these bandpass characteristics to achieve bandpass in the high-frequency band and adjacent frequency bands. Setting the outer and inner conductors to have uniform width and form a closed strip-shaped circuit facilitates design and production, simplifies production, and saves manpower and resources.

[0049] Specifically, in one embodiment, such as Figure 3 The width of the inner conductor shown is greater than the width of the outer conductor. For example, the inner conductor is a solid conductive pattern. The conductor width is a variable design parameter. A wider inner conductor than the outer conductor can increase the frequency response bandwidth and resist manufacturing errors. In an extreme case, the inner conductor can be a solid conductive pattern. However, excessive metal can lead to losses due to current flow. Therefore, the specific linewidth value needs to be considered comprehensively, making it a preferred design parameter.

[0050] The LC equivalent loading structure 2 includes: a capacitor equivalent structure and an inductor equivalent structure connected in parallel; and a cascaded gap loop structure and LC equivalent loading structure to form a scattering suppression structure. For example, as shown... Figure 4 As shown, in the prior art, multiple frequency selection units are directly cascaded without mutual isolation. The new shape profile generates new frequency response characteristics, unnecessarily affecting the original frequency response characteristics, typically manifesting as a decrease in the stopband resonant frequency and a deterioration in passband performance. This embodiment adds an LC equivalent loading structure between multiple frequency selection units, reducing the impact on performance caused by direct cascading. For example... Figure 5The figure shows the differences in plane wave transmission performance (expressed by transmission coefficient) in three cases: a single slit loop structure, a direct cascade of single slit loop structures, and a single slit loop structure cascaded through an LC equivalent loading structure.

[0051] The scattering suppression structure provided in this embodiment of the invention uses an LC equivalent loading structure with specific frequency response characteristics to connect the gap loop structure, thereby reducing the interference of the scattered field while maintaining the frequency response characteristics unchanged.

[0052] Specifically, in one embodiment, such as Figure 6 As shown, the design principle of the LC equivalent loading structure is based on the equivalent principle of the LC parallel circuit. The frequency characteristics of the LC parallel loading circuit are determined by the parameters of the capacitor and inductor. When the parameters of the capacitor and inductor are matched, the circuit exhibits resonant characteristics. The LC equivalent loading structure designed using this principle ensures the scattering characteristics within the operating frequency band. For example, based on the goal of scatter suppression, the designed LC parallel circuit has a single stopband characteristic. Therefore, based on the equivalent principle of inductance and capacitance, an LC equivalent loading structure is designed. In the mobile communication frequency band, the combination of radio frequency transmission lines is preferentially used to implement this LC equivalent loading structure.

[0053] Specifically, in one embodiment, such as Figure 7 As shown, the capacitor equivalent structure 21 and the inductor equivalent structure 22 in the LC equivalent loading structure are located on both sides of the two parallel nodes, respectively.

[0054] In another embodiment, such as Figure 8 As shown, the capacitor equivalent structure 21 and the inductor equivalent structure 22 are located on the same side of the two parallel nodes, and the capacitor equivalent structure is located inside the inductor equivalent structure, making the structure more compact.

[0055] like Figure 9 As shown, this is a specific embodiment of the present invention. The gap loop structure is a closed strip circuit in which both the outer conductor and the inner conductor are of uniform width. The LC equivalent loading structure is that the capacitor equivalent structure and the inductor equivalent structure are located on the same side of the two parallel nodes, and the capacitor equivalent structure is located inside the inductor equivalent structure.

[0056] Example 2

[0057] This invention provides an electromagnetic boundary, including an isolation sheet, on which a scattering suppression structure as described in any of Embodiment 1 is provided.

[0058] Example 3

[0059] This invention provides a low-frequency radiation unit, including a radiation arm, on which a scattering suppression structure as described in any of Embodiment 1 is provided.

[0060] Example 4

[0061] This invention provides an antenna element comprising: any of the scattering suppression structures in Embodiment 1, the electromagnetic boundary in Embodiment 2, or the low-frequency radiating element in Embodiment 3. Exemplarily, the scattering suppression structure from Embodiment 1 is used in the design of the low-frequency radiating element and the electromagnetic boundary placed close to the antenna element in a high- and low-frequency co-aperture antenna, and applied to the radiating element using a "loading technique" to further reduce scattering from the remaining portion except for the loading structure.

[0062] In this embodiment of the invention, the forms of the gap loop structure and the LC equivalent loading structure can be flexibly designed according to the actual situation:

[0063] like Figure 10 The diagram illustrates the application of a combination of a "slotted loop structure" and an "LC equivalent loading structure" to a "ring-shaped" antenna element, using frequency selection elements of different sizes within the same antenna element; as shown... Figure 11 The diagram shows the application of a combination of a "slot loop structure" and an "LC equivalent loading structure" to a "linear" antenna element, where "a" is the feed point; as shown... Figure 12 The diagram shows the application of a combination of a "slot loop structure" and an "LC equivalent loading structure" to a "monopole" antenna element, where "a" is the feed point and "b" is the antenna ground plane. Figure 13 The diagram shows the implementation of the "slot loop structure" using an elliptical slot loop, combined with the "LC equivalent loading structure", and then applied to the "linear" radiating element, where "a" is the feed point.

[0064] The antenna unit provided in this embodiment of the invention utilizes the scattering suppression structure in Embodiment 1, which can better suppress scattering suppression induced current. It can be set on the isolator at the electromagnetic boundary or on the radiating arm of the radiating unit. Using the isolator or radiating arm with the scattering suppression structure to design the antenna can improve the performance indicators of the multi-frequency antenna, and make debugging easier, facilitate design optimization, and have a simpler structure and stronger versatility.

[0065] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A scattering suppression structure, characterized in that, include: A slotted loop structure includes: an outer closed conductor, an inner closed conductor, and a slotted loop formed between the outer closed conductor and the inner closed conductor, wherein the outer closed conductor and the inner closed conductor are both of uniform width and form a closed strip-shaped circuit; An LC equivalent loading structure includes: a capacitor equivalent structure and an inductor equivalent structure connected in parallel; the capacitor equivalent structure and the inductor equivalent structure in the LC equivalent loading structure are located on both sides of two parallel nodes; or the capacitor equivalent structure and the inductor equivalent structure are located on the same side of two parallel nodes, and the capacitor equivalent structure is located inside the inductor equivalent structure. The cascaded gap loop structure and the LC equivalent loading structure form a scattering suppression structure.

2. The scattering suppression structure according to claim 1, characterized in that, The length of the slot loop is equal to the operating wavelength corresponding to any frequency in the high-frequency band of the high-frequency and low-frequency common aperture antenna element.

3. The scattering suppression structure according to claim 2, characterized in that, Both the outer conductor and the inner conductor are of uniform width and form a closed strip-shaped circuit.

4. The scattering suppression structure according to claim 3, characterized in that, The width of the inner conductor is greater than the width of the outer conductor.

5. The scattering suppression structure according to claim 4, characterized in that, The inner conductor is a solid conductive pattern.

6. The scattering suppression structure according to claim 1, characterized in that, The design principle of the LC equivalent loading structure is the equivalent principle of the LC parallel loading circuit.

7. An electromagnetic boundary, characterized in that, It includes an isolation sheet, wherein the isolation sheet is provided with a scattering suppression structure as described in any one of claims 1 to 6.

8. A low-frequency radiating unit, characterized in that, It includes a radiating arm, on which a scattering suppression structure as described in any one of claims 1 to 6 is provided.

9. An antenna element, characterized in that, The antenna element includes: The electromagnetic boundary as described in claim 7 or the low-frequency radiation unit as described in claim 8.

Images