Noise shielding structure and portable terminal device

Abstract

The application provides a noise shielding structure and a portable terminal device, which can be applied to the technical field of noise shielding. The noise shielding structure comprises: an air inlet and outlet support configured as a plate-shaped structure and having a first surface and a second surface facing away from each other; a first frequency selective surface structure and a second frequency selective surface structure arranged on both sides of the first surface along the length direction of the air inlet and outlet support; and a third frequency selective surface structure arranged on the middle region of the second surface. In the projection of the first surface as a projection plane and the thickness direction of the air inlet and outlet support as a projection direction, the projection of the third frequency selective surface structure is staggered with the projections of the first frequency selective surface and the second frequency selective surface. The sum of the coverage ranges of the first frequency selective surface structure, the second frequency selective surface structure and the third frequency selective surface structure along the length direction of the air inlet and outlet support matches the length of the air inlet and outlet support.

Description

Technical Field

[0001] This application relates to the field of noise shielding technology, and in particular to a noise shielding structure and a portable terminal device. Background Technology

[0002] As the performance requirements of laptops increase, the internal high-speed signal rates also rise, leading to increased RF (Radio Frequency) noise. Simultaneously, due to the close proximity of the laptop's antenna to the motherboard, RF noise generated by the motherboard can easily reach the antenna through the air intake and exhaust vents, thus affecting antenna performance. Therefore, effective RF noise shielding is crucial for ensuring the performance of the laptop's antenna and the overall stability of the laptop.

[0003] However, there is a conflict between RF noise shielding and heat dissipation requirements in the structural design of laptops. Therefore, how to effectively suppress RF noise while meeting the heat dissipation requirements of THM (Thermal Heat Management) is a technical problem that needs to be solved in related technologies. Summary of the Invention

[0004] In view of the above problems, this application provides a noise shielding structure and a portable terminal device.

[0005] According to a first aspect of this application, a noise shielding structure is provided, comprising: an air inlet / outlet bracket configured as a plate-like structure having a first surface and a second surface facing away from each other, and heat dissipation holes penetrating the first surface and the second surface; a first frequency selective surface structure and a second frequency selective surface structure respectively disposed on both sides of the first surface along the length direction of the air inlet / outlet bracket; a third frequency selective surface structure disposed in the middle region of the second surface; in a projection with the first surface as the projection plane and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the third frequency selective surface structure is misaligned with the projections of the first and second frequency selective surfaces; and the sum of the coverage areas of the first, second, and third frequency selective surface structures along the length direction of the air inlet / outlet bracket matches the length of the air inlet / outlet bracket.

[0006] According to an embodiment of this application, the first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure all have metal conductive patterns. The metal conductive patterns include at least two unit patterns arranged along the length direction of the air inlet / outlet bracket, and each unit pattern has a through hole.

[0007] According to embodiments of this application, the above-mentioned unit pattern is configured as at least one of a rectangular ring structure, a cross-shaped structure, and an I-shaped structure.

[0008] According to an embodiment of this application, in the projection with the first surface as the projection surface and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the heat dissipation hole coincides with the projection of the through hole in the third frequency selection surface structure.

[0009] According to an embodiment of this application, the antenna of the portable terminal device is disposed on the first surface of the aforementioned air inlet / outlet bracket; and the aforementioned second surface is configured to face the motherboard of the aforementioned portable terminal device.

[0010] According to an embodiment of this application, in a projection with the first surface as the projection surface and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the motherboard coincides with the projection of the air inlet / outlet bracket.

[0011] According to an embodiment of this application, the third frequency selection surface structure is configured to share a grounding path with the grounding portion of the antenna.

[0012] According to an embodiment of this application, the noise shielding structure further includes: a first elastic conductive element and a second elastic conductive element; the first elastic conductive element is disposed on the upper edge of the third frequency selective surface structure and contacts the input unit of the portable terminal device, the input unit being located above the motherboard; the second elastic conductive element is disposed on the lower edge of the third frequency selective surface structure and contacts the outer casing of the portable terminal device, thereby sequentially forming a grounding path consisting of the input unit, the first elastic conductive element, the third frequency selective surface structure, the second elastic conductive element, and the outer casing.

[0013] According to an embodiment of this application, at least one end of the air inlet / outlet bracket along its length is provided with a mounting portion, and the air inlet / outlet bracket is connected to the heat dissipation fins through the mounting portion; the gap between the air inlet / outlet bracket and the heat dissipation fins is configured to be less than the critical leakage distance of noise in a preset frequency band.

[0014] A second aspect of this application provides a portable terminal device, which includes the aforementioned noise shielding structure; the noise shielding structure is disposed between the motherboard and the antenna of the portable terminal device.

[0015] According to the noise shielding structure provided in this application, the first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure arranged on the air inlet and outlet bracket can form a "closed barrier" in space. The first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure can jointly cover the noise propagation path, thereby blocking the RF noise of the motherboard from passing through the air inlet and outlet, thus solving the problem of RF noise interference to the antenna. Attached Figure Description

[0016] The above-mentioned contents, other objects, features and advantages of this application will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0017] Figure 1 This illustration schematically shows a structural diagram of a noise shielding scheme in the related art according to an embodiment of this application;

[0018] Figure 2 A schematic diagram of an air inlet / outlet bracket according to an embodiment of this application is shown.

[0019] Figure 3 A schematic diagram of a noise shielding structure according to an embodiment of this application is shown.

[0020] Figure 4 A schematic diagram of the unit pattern in the second surface of the air inlet / outlet bracket according to an embodiment of this application is shown.

[0021] Figure 5 A schematic diagram of a unit pattern in the second surface of an air inlet / outlet bracket according to another embodiment of this application is shown.

[0022] Figure 6 The diagram illustrates different opening ratios of the air inlet and outlet brackets according to embodiments of this application.

[0023] Figure 7 This schematic diagram illustrates the relative positions of the motherboard, air inlet / outlet bracket, and antenna according to an embodiment of this application.

[0024] Figure 8 The schematic diagram illustrates the relative positions of the input unit, rear shell, and air inlet / outlet bracket according to an embodiment of this application.

[0025] Figure 9 This schematically illustrates a simulation diagram of the current distribution on the first surface of the air inlet / outlet bracket in a noise shielding structure according to an embodiment of this application.

[0026] Figure 10 This schematically illustrates a simulation diagram of the current distribution on the second surface of the air inlet / outlet bracket in a noise shielding structure according to an embodiment of this application.

[0027] Figure 11 This schematic diagram illustrates the frequency response of a noise shielding structure according to an embodiment of the present application for a preset frequency band.

[0028] Figure 12 This schematic diagram illustrates the frequency response of an air inlet / outlet bracket without an FSS structure according to an embodiment of this application for a preset frequency band.

[0029] Figure 13 The diagram illustrates the impact of the FSS-added structure and the non-FSS-added structure on antenna performance according to embodiments of this application. Detailed Implementation

[0030] The embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this application. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this application for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0032] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0033] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0034] In the process of developing this application, it was discovered that in related technologies, shielding solutions often affect the internal airflow channel, occupy motherboard space, and prevent the overall performance from being effectively improved.

[0035] Specifically, the shielding solution involves adding Mechanical Engineering (ME) materials (auxiliary means and materials used in manufacturing) to the air inlet and outlet brackets to absorb or block noise, minimizing the noise reaching the antenna to meet the performance requirements of the laptop. Simultaneously, replacing the laptop's air inlet and outlet brackets with metal and minimizing the opening size can also block noise. However, TMH requires the air inlet and outlet opening ratio to be as large as possible to meet ventilation and heat dissipation needs. Therefore, while this solution can block noise, it cannot meet the heat dissipation requirements of THM.

[0036] Therefore, the main measures taken in related technologies to address RF noise include increasing ME solution shielding and adding metal isolation barriers to block and isolate noise.

[0037] Figure 1 The diagram illustrates a structural schematic of a noise shielding scheme in the related art according to an embodiment of this application.

[0038] like Figure 1 As shown, a row of metal vertical ribs 120 is added to the area corresponding to the antenna on the air inlet / outlet bracket 110 to form a barrier-like effect, thereby shielding the antenna from the influence of RF noise.

[0039] However, adding ME solution not only increases material costs but also increases manual application costs, which is time-consuming and labor-intensive. At the same time, the dense distribution of metal isolation walls is very unfavorable to the airflow and exhaust of THM, thus affecting the heat dissipation performance of THM, especially the internal airflow scheme. Furthermore, this shielding scheme cannot directionally block RF noise in specific frequency bands, making it inflexible. Moreover, due to structural and spatial limitations, the metal isolation walls can only provide partial shielding for the antenna location, while having no shielding effect on the larger air outlets on both sides.

[0040] Therefore, embodiments of this application provide a noise shielding structure to effectively suppress the impact of RF noise on antenna performance while meeting the heat dissipation requirements of THM.

[0041] Traditional metal shielding walls are three-dimensional solid barriers, while FSS (Frequency Selective Surface) was originally a two-dimensional planar concept (like a single-layer patch on an radome). In laptop applications, the air intake / exhaust vent bracket is a thick, three-dimensional structure, and noise can diffract from the front, back, or even the sides. If FSS is only used on one side (e.g., only on the front), noise from the motherboard can still diffract through gaps on the back or sides of the bracket, resulting in incomplete shielding.

[0042] Based on this, in order to solve the three-dimensional shielding problem, this application arranges conductors (FSS structure) on both the front and back of the plastic air inlet and outlet brackets, and electromagnetically "wraps" the heat dissipation holes to form an "electromagnetic sealed chamber" for a specific frequency band.

[0043] Figure 2 A schematic diagram of an air inlet / outlet bracket according to an embodiment of this application is shown.

[0044] like Figure 2 As shown, the air inlet / outlet bracket 200 is configured as a plate-like structure, having a first surface 210 and a second surface 220 facing away from each other, and heat dissipation holes penetrating the first surface 210 and the second surface 220.

[0045] Therefore, the air inlet / outlet bracket 200 is equipped with multiple heat dissipation holes.

[0046] For example, in Figure 2 In the first surface 210, the opening 211 is at the two ends of the same heat dissipation hole, that is, the heat dissipation hole penetrates the first surface 210 and the second surface 220 of the air inlet / outlet bracket 200.

[0047] In one embodiment, arrow X points along the length of the air inlet / outlet bracket 200, and arrow Y points along the thickness of the air inlet / outlet bracket 200, with the length direction perpendicular to the thickness direction. The material of the air inlet / outlet bracket can be, for example, plastic.

[0048] In one embodiment, the heat dissipation holes penetrate the first and second surfaces of the air inlet / outlet bracket along the thickness direction of the air inlet / outlet bracket.

[0049] Figure 3 A schematic diagram of a noise shielding structure according to an embodiment of this application is shown.

[0050] like Figure 3 As shown, the noise shielding structure also includes a first frequency selective surface structure 310 and a second frequency selective surface structure 320, which are respectively disposed on both sides of the first surface 210 along the length direction of the air inlet / outlet bracket. For example, the first frequency selective surface structure 310 and the second frequency selective surface structure 320 are respectively disposed on both sides of the first surface 210 along the length direction, such as... Figure 3 Regions 340 and 360 are shown.

[0051] In one embodiment, the noise shielding structure further includes a third frequency selective surface structure 330, which is disposed in the middle region of the second surface 220. For example, the third frequency selective surface structure is disposed in such a... Figure 3The middle region 370 of the second surface 220 is shown. Because the antenna is very close to the motherboard, RF noise can easily reach the antenna end through the air inlet and outlet, thus affecting the antenna performance.

[0052] As can be seen, the frequency selection surface structure in the noise shielding structure of this application is arranged in an "opposite" manner. Specifically, the first frequency selection surface structure and the second frequency selection surface structure are arranged on the first surface of the air inlet and outlet bracket, and the third frequency selection surface structure is arranged on the second surface of the air inlet and outlet bracket.

[0053] Based on this, in order to block the RF noise of the motherboard from passing through the air inlet and outlet, the noise shielding structure of this application, which includes the first frequency selection surface structure, the second frequency selection surface structure, and the third frequency selection surface structure on the first surface of the air inlet and outlet bracket, is further configured as follows.

[0054] In the projection with the first surface 210 as the projection surface and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the third frequency selection surface structure 330 is misaligned with the projections of the first frequency selection surface 310 and the second frequency selection surface 320, that is, there is no overlap between the projection of the third frequency selection surface structure and the projections of the first and second frequency selection surfaces.

[0055] exist Figure 3 In the diagram, the direction of arrow X indicates the length direction of the air inlet / outlet bracket, and the direction of the thickness direction of the air inlet / outlet bracket (…). Figure 2 The direction indicated by the middle arrow Y is not shown, but... Figure 3 The thickness of the central air inlet / outlet bracket is perpendicular to its length and points outward from the paper.

[0056] Furthermore, the sum of the coverage areas of the first frequency selection surface structure 310, the second frequency selection surface structure 320, and the third frequency selection surface structure 330 along the length direction of the air inlet / outlet bracket matches the length of the air inlet / outlet bracket.

[0057] exist Figure 3 In the design, region 350 on the first surface 210 and region 370 on the second surface 220 of the air inlet / outlet bracket are aligned along the length of the air inlet / outlet bracket. Specifically, with the first surface 210 as the projection plane and the thickness direction of the air inlet / outlet bracket as the projection direction, the projections of region 370 on the second surface 220 and region 350 on the first surface 210 are aligned on opposite sides along the length of the air inlet / outlet bracket. Furthermore, the projections of region 340 and region 350 on the first surface 210 are aligned on the side closest to each other along the length, and the projections of region 350 and region 360 on the first surface 210 are also aligned on the side closest to each other along the length.

[0058] Therefore, with the first surface 210 as the projection plane and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the third frequency selection surface structure falls within the projection of region 350 in the first surface 210 of the air inlet / outlet bracket. Specifically, the projection of the third frequency selection surface structure overlaps with the projection of region 340 in the length direction on both sides. Furthermore, the sum of the lengths of the areas covered by the first frequency selection surface structure 310, the second frequency selection surface structure 320, and the third frequency selection surface structure 330 in the length direction of the air inlet / outlet bracket is consistent with the length of the air inlet / outlet bracket.

[0059] For example, the sum of the lengths of the first frequency selection surface structure 310, the second frequency selection surface structure 320, and the third frequency selection surface structure 330 in the length direction of the air inlet / outlet bracket is equal to the length of the air inlet / outlet bracket.

[0060] Based on this, the noise shielding structure of this application can form a "closed barrier" that absorbs noise through the first frequency selective surface structure, the second frequency selective surface structure and the third frequency selective surface structure, thereby blocking the RF niose of the motherboard from passing through the air inlet and outlet.

[0061] Figure 2 and Figure 3 The arrangement and size of the heat dissipation holes on the first and second surfaces of the air inlet / outlet bracket 200 shown are merely illustrative embodiments.

[0062] According to the embodiments of this application, the first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure disposed on the air inlet and outlet bracket can form a "closed barrier" in space to cover the noise propagation path together through the first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure, thereby blocking the RF noise of the motherboard from passing through the air inlet and outlet, thereby solving the problem of RF noise interference to the antenna.

[0063] According to embodiments of this application, the first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure all have metallic conductive patterns. The metallic conductive patterns include at least two unit patterns arranged along the length direction of the air inlet / outlet bracket, and each unit pattern has a through hole.

[0064] In one embodiment, the first frequency-selective surface structure, the second frequency-selective surface structure, and the third frequency-selective surface structure are FSS (Frequency Selective Surface) structures. The first frequency-selective surface structure, the second frequency-selective surface structure, and the third frequency-selective surface structure each have their own conductive metal patterns on the first surface and the second frequency-selective surface structure, respectively. For example, the conductive metal pattern on the first surface of the first frequency-selective surface structure can be as follows: Figure 3 As shown in the diagram of the first frequency selective surface structure 310, the metallic conductive pattern of the second frequency selective surface structure on the first surface can be as follows: Figure 3 The second frequency selective surface structure 320 is shown in the diagram. The metallic conductive pattern of the third frequency selective surface structure on the second surface can be as follows: Figure 3 The first frequency selected is shown in the graph of surface structure 330.

[0065] Among them, the metallic conductive pattern can characterize the pattern of the area covered by the frequency-selective surface structure on the surface of the air inlet / outlet bracket.

[0066] In one embodiment, the first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure each have different metal conductive patterns. By designing the metal conductive patterns of the first frequency selective surface structure, the noise of the preset frequency band can be blocked from passing through the air inlet and outlet, thereby affecting the antenna performance.

[0067] Figure 4 A schematic diagram of the unit pattern in the second surface of the air inlet / outlet bracket according to an embodiment of this application is shown.

[0068] like Figure 4 As shown, taking the connected unit patterns on the second surface 220 of the air inlet / outlet bracket as an example, the metallic conductive patterns of the third frequency-selective surface structure may include at least two unit patterns arranged along the length direction of the air inlet / outlet bracket, such as... Figure 4 The diagram shows unit patterns 410 and 420 arranged along the length of the air inlet / outlet bracket (in the direction of arrow X). Specifically, unit pattern 410 represents the pattern of the third frequency-selective surface structure on the second surface 220 falling into the structural portion within region 430, and unit pattern 420 represents the pattern of the third frequency-selective surface structure on the second surface 220 falling into the structural portion within region 440.

[0069] In one embodiment, two adjacent unit patterns in the metal conductive pattern along the length direction of the air inlet / outlet bracket may or may not overlap. Figure 4The relative positions and shapes of the two adjacent unit graphics shown are merely illustrative embodiments.

[0070] Figure 5 A schematic diagram of a unit pattern in the second surface of an air inlet / outlet bracket according to another embodiment of this application is shown.

[0071] like Figure 5 As shown, the unit patterns 510 and 520 arranged along the length direction of the air inlet / outlet bracket (in the direction pointed by arrow X) do not overlap. Figure 5 The relative positions and shapes of the two adjacent unit graphics shown are merely illustrative embodiments.

[0072] According to an embodiment of this application, the first frequency selective surface structure, the second frequency selective surface, and the third frequency selective surface structure have metallic conductive patterns to block noise of a preset frequency band from passing through the air inlet and outlet. Furthermore, the first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure are all provided with through holes to allow free airflow and improve the heat dissipation performance of the THM.

[0073] According to embodiments of this application, the unit pattern is configured as at least one of a rectangular ring structure, a cross-shaped structure, and an I-shaped structure.

[0074] According to embodiments of this application, the unit pattern of the metallic conductive pattern being configured as a rectangular ring structure refers to a frequency-selective surface structure covering the surface of the air inlet / outlet bracket to form multiple rectangular rings, for example... Figure 4 and Figure 5 The unit pattern shown is configured as a rectangular ring structure. The metal conductive pattern, including unit patterns configured as a cross-shaped structure, refers to the frequency selective surface structure covering the surface of the inlet / outlet bracket to form multiple cross-shaped structures. The metal conductive pattern, including unit patterns configured as an I-beam structure, refers to the frequency selective surface structure covering the surface of the inlet / outlet bracket to form multiple I-beam structures.

[0075] According to the embodiments of this application, different structural configurations of the unit pattern are selected so that the first frequency selection surface, the second frequency selection surface and the third frequency selection surface disposed on the surface of the air inlet and outlet bracket can shield the RF noise of the motherboard, so that the noise reaching the antenna is as small as possible, thereby avoiding the impact of noise on the antenna performance.

[0076] In one embodiment, the cell pattern can also be configured as an "irregular" aperiodic structure.

[0077] Taking a rectangular ring structure and its variations as a unit pattern, the resonant frequency of the rectangular ring has a direct correlation with the ring's circumference (approximately equal to half a wavelength), making it predictable and easy to tune. The linear structure of the rectangular ring is well-suited for the fabrication processes of PCB / plastic antennas, such as LDS (laser-directed stereolithography), offering high precision and controllable costs. Furthermore, by nesting rectangular rings of different sizes, multi-band suppression can be easily achieved, reserving space for future expansion.

[0078] The area around the air inlet and outlet is obstructed by antennas, screw posts, clips, and other obstacles, making it impossible to provide a regular, continuous planar space for laying out an infinitely periodic structure. Therefore, an "irregular" layout can adapt to irregular spaces. The distribution of noise sources (motherboard) and the position of antennas are not symmetrical; therefore, a stronger or denser FSS structure needs to be arranged along the critical path (such as the area directly opposite the motherboard), while simplification is required in secondary areas. This "aperiodic" layout achieves optimized allocation of shielding resources. Furthermore, within a limited size, aperiodic arrangement can better suppress the grating lobes generated by periodic structures at large angles of incidence, improving stability in real-world environments.

[0079] According to an embodiment of this application, in a projection with the first surface as the projection surface and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the heat dissipation hole coincides with the projection of the through hole in the third frequency selection surface structure.

[0080] According to embodiments of this application, frequency selective surface structures are provided on the first and second surfaces of the air inlet / outlet bracket to absorb motherboard noise and prevent noise from passing through the air inlet / outlet bracket and affecting antenna performance. Simultaneously, the air inlet / outlet bracket also serves for ventilation and heat dissipation to meet the heat dissipation requirements of the TMH (Thunder Modem). The TMH requires the air inlet / outlet opening ratio to be as large as possible to meet these ventilation and heat dissipation needs.

[0081] Therefore, the frequency selective surface structure set on the surface of the air inlet and outlet bracket needs to not only block the noise of the motherboard from passing through the air inlet and outlet to avoid affecting the antenna performance, but also meet the heat dissipation requirements of TMH.

[0082] In one embodiment, the frequency-selective surface structure in the noise shielding structure of this application is a precisely designed metal pattern (such as a rectangular ring) printed on the edge of the air inlet / outlet bracket, rather than a solid baffle. For example, it can be as follows: Figure 3 Design of surface structures for mid-frequency selection.

[0083] Taking unit pattern 410 as an example, the area enclosed by the inner edge 450 of unit pattern 410 is the through hole formed by unit pattern 410. Furthermore, unit pattern 410 is located at the edge of the opening 460 of the heat dissipation hole.

[0084] Therefore, for the third frequency selection surface structure set on the second surface of the air inlet / outlet bracket, in the projection with the first surface as the projection plane and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the heat dissipation hole coincides with the projection of the through hole in the third frequency selection surface structure.

[0085] Based on this, the noise shielding structure of this application can liberate the opening ratio of the air inlet and outlet brackets. Specifically, the FSS pattern is only distributed on the edge or frame of the heat dissipation holes in the air inlet and outlet brackets, and most of the central area of ​​the opening of the through hole is an empty plastic or metal-free area, allowing air to flow freely, thus reflecting a high opening ratio.

[0086] According to embodiments of this application, since the filtering of the FSS structure relies on the resonant characteristics of the FSS pattern rather than the physical size of the gaps, the metal linewidth (W1) of the FSS structure can be made very fine (e.g., 0.2~0.5mm), while the thickness of traditional metal baffles is usually over 1mm. Therefore, this application uses extremely fine "intelligent filter lines" to replace the heavy "solid baffles," significantly reducing physical obstruction. Based on this, since the through-holes are distributed on the inlet / outlet brackets at or around the edges of the heat dissipation holes, the frequency-selective surface structure does not affect the opening ratio of the inlet / outlet brackets, allowing free airflow and improving the heat dissipation performance of the THM.

[0087] Based on the above, since the filtering of the FSS structure relies on the resonant characteristics of the FSS pattern rather than the physical size of the gaps, the size of a single through-hole is not strictly limited by the wavelength and can be made much larger than the noise wavelength (for example, through-holes several centimeters long can be designed), thereby significantly increasing the overall aperture ratio. However, there is a contradiction between increasing the aperture ratio to meet heat dissipation requirements and ensuring noise shielding in the FSS structure design. Specifically, as the aperture ratio increases, the relative coverage of the FSS pattern (i.e., the conductive metal pattern) on the air inlet / outlet bracket decreases, which theoretically reduces its electromagnetic interaction capability, potentially leading to a shift in the resonant peak, a decrease in the Q value (wider bandwidth), and a shallower suppression depth. Furthermore, unlike traditional solid baffles, the performance of the FSS does not depend on the physical shielding area but on the electromagnetic characteristics of the unit pattern. Therefore, the impact of increasing the aperture ratio can be compensated for by optimizing the pattern design.

[0088] Based on this, to ensure both heat dissipation performance and noise shielding requirements are met, the border area of ​​the FSS structure pattern can be narrowed when the aperture size is increased. Specifically, for miniaturization of the FSS structure pattern, a more tortuous fractal design or a substrate with a higher dielectric constant can be used to achieve the same electrical length (resonant frequency) in a smaller space. To improve integration, the unit pattern density can be increased within a limited border or a non-plane coupling design with multiple virtual stacks can be sampled. To adjust the linewidth (W1) of the FSS structure, the metal linewidth can be optimized to seek the best impedance and resonance strength within the limits of processing accuracy.

[0089] When the shape of the opening changes, the FSS structure may need to adapt to the non-rectangular border. Specifically, the FSS structure may evolve from a standard rectangular ring to a trapezoid, hexagon, etc., to fit the boundary and achieve unit shape adaptation. The unit pattern of the FSS structure can break the strict periodicity and adopt a gradient or non-periodic arrangement to form an effective filtering response in heterogeneous space.

[0090] With extremely high overall aperture requirements, the total amount of metal material in the FSS structure is strictly limited. Specifically, the metal material is concentrated for designing the most critical resonant unit, rather than being uniformly covered, prioritizing efficiency. The filtering effect is generated by strong electromagnetic coupling between the front and back FSS structures, rather than the independent performance of a single-sided structure.

[0091] Based on this, while increasing the opening ratio of the air inlet and outlet brackets, the metal conductive patterns of the first frequency selection surface structure, the second frequency selection surface structure and the third frequency selection surface structure can be designed to ensure that heat dissipation requirements are met while blocking noise of the preset frequency band from passing through the air inlet and outlet.

[0092] Figure 6 The diagram illustrates different opening ratios of the air inlet / outlet brackets according to embodiments of this application.

[0093] In one embodiment, the second surface of the air inlet / outlet bracket is as follows: Figure 3 The ventilation holes in region 370 are relatively dense and smaller than those in regions 340 and 360. Therefore, the opening ratio of the ventilation holes in region 370 on the second surface of the air inlet / outlet bracket is further increased to improve heat dissipation performance. Thus, increasing the opening ratio refers to increasing the opening ratio of the air inlet / outlet bracket itself, specifically, increasing the opening ratio of region 370 on the second surface.

[0094] like Figure 6 As shown, by removing multiple grids 620 of the air inlet and outlet bracket within the area enclosed by the through hole 610, a new heat dissipation hole is formed, and an FSS structure is set at the edge of the new heat dissipation hole, the through hole 610 can be formed.

[0095] Specifically, during the design of the aperture ratio and the FSS structure, the aperture ratio is gradually increased. For example, multiple grids 620 of the air inlet and outlet brackets within the area enclosed by the through hole 630 are gradually removed, and multiple grids 620 of the air inlet and outlet brackets within the area enclosed by the through hole 640 are removed, etc., to test how much the aperture ratio can be increased to ensure that the heat dissipation performance is improved while solving the problem of radio frequency noise interference to the antenna.

[0096] Figure 3 The third frequency selection surface structure 330 provided on the second surface of the air inlet / outlet bracket shown is provided after increasing the opening ratio.

[0097] The opening ratio of the air inlet / outlet bracket represents the ratio of the sum of the areas of the heat dissipation holes in the air inlet / outlet bracket to the total area of ​​the first and second surfaces of the air inlet / outlet bracket.

[0098] According to an embodiment of this application, the antenna of the portable terminal device is disposed on the first surface of the air inlet / outlet bracket; and the second surface is configured to face the motherboard of the portable terminal device.

[0099] In one embodiment, the portable terminal device may be, for example, a laptop computer. The portable terminal device includes a motherboard, antenna, air vent bracket, and a noise shielding structure disposed within the portable terminal device.

[0100] Figure 7 The diagram illustrates the relative positions of the motherboard, air inlet / outlet bracket, and antenna according to an embodiment of this application.

[0101] like Figure 7 As shown, along the thickness direction of the air inlet / outlet bracket 200, the portable terminal device sequentially includes a motherboard 710, an air inlet / outlet bracket 200, and an antenna 720. Specifically, the antenna 720 is disposed on the first surface 210 of the air inlet / outlet bracket 200, that is, the first surface 210 faces the antenna 720, and the second surface 220 of the air inlet / outlet bracket 200 faces the motherboard 710.

[0102] For example, the FSS structure and antenna are designed on the same LDS bracket, that is, on the same air inlet / outlet bracket.

[0103] Figure 7 The diagram shown is only for illustrating the relative positional relationship of the motherboard, air inlet / outlet bracket, and antenna along the thickness direction of the air inlet / outlet bracket, and does not represent the actual positional design; it is merely an illustrative embodiment.

[0104] In one embodiment, the FSS structure is designed together with the antenna, such as on the same LDS bracket, which is suitable for base antennas. Furthermore, the design needs to take into account both antenna and FSS performance, making the design more difficult.

[0105] Based on this, since the first surface of the air inlet / outlet bracket is adjacent to the antenna, the primary task of the first and second frequency selection surface structures set on the first surface is to ensure antenna performance. Therefore, the first and second frequency selection surface structures need to play a "transparent" or "benignly grounded" role. The second surface of the air inlet / outlet bracket faces the motherboard noise source directly, and its primary task is efficient filtering. Therefore, the two FSS structures of the air inlet / outlet bracket in this application must be different, and the "different surfaces" are intelligent solutions generated to meet conflicting requirements in a differentiated manner.

[0106] According to an embodiment of this application, in a projection with the first surface as the projection surface and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the motherboard coincides with the projection of the air inlet / outlet bracket.

[0107] Because the antenna in portable terminal devices is very close to the motherboard, noise generated by the motherboard can easily reach the antenna through the air inlet / outlet bracket, thus affecting antenna performance. Therefore, a first frequency selection surface structure and a second frequency selection surface structure are respectively provided on both sides of the first surface of the air inlet / outlet bracket, and a third frequency selection surface structure is provided in the middle area of ​​the second surface of the air inlet / outlet bracket. Furthermore, the sum of the lengths of the first, second, and third frequency selection surface structures along the length of the air inlet / outlet bracket is the same as the length of the air inlet / outlet bracket. Thus, by forming a "closed barrier" on the surface of the air inlet / outlet bracket, noise from the motherboard is blocked from reaching the antenna through the air inlet / outlet bracket.

[0108] Meanwhile, to prevent noise generated by the motherboard from reaching the antenna directly without passing through the air inlet / outlet bracket, in a projection with the first surface as the projection plane and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the motherboard coincides with the projection of the air inlet / outlet bracket. Specifically, the projection range of the air inlet / outlet bracket can completely cover the projection range of the motherboard.

[0109] According to an embodiment of this application, since the air inlet / outlet bracket is located between the motherboard and the antenna, the first surface of the air inlet / outlet bracket faces the antenna, that is, the first frequency selection surface structure and the second frequency selection surface structure of the first surface directly face the antenna to ensure that the radiation performance of the antenna is not affected; the second surface of the air inlet / outlet bracket faces the motherboard, that is, the third frequency selection surface structure bracket of the second surface directly faces the motherboard. Furthermore, since the projection of the motherboard coincides with the projection of the air inlet / outlet bracket in the thickness direction of the air inlet / outlet bracket, the first frequency selection surface structure, the second frequency selection surface structure, and the third frequency selection surface structure disposed on the air inlet / outlet bracket can be used to block noise from the motherboard, preventing noise generated by the motherboard from reaching the antenna directly without passing through the air inlet / outlet bracket, thereby avoiding affecting the performance of the antenna.

[0110] According to an embodiment of this application, the third frequency selection surface structure is configured to share a ground path with the ground portion of the antenna.

[0111] According to an embodiment of this application, since the first surface of the air inlet / outlet bracket faces the antenna, in order to enhance the filtering effect of the third frequency selection surface structure, the third frequency selection surface structure and the grounding part of the antenna share a grounding path.

[0112] According to the embodiments of this application, since the third frequency selective surface structure and the grounding part of the antenna share the same grounding path, a stable potential reference surface is provided for the antenna. At the same time, the clutter energy absorbed by the third frequency selective surface structure is quickly discharged to the ground through the grounding terminal, so as to avoid energy accumulation causing secondary interference to the antenna.

[0113] According to an embodiment of this application, the noise shielding structure further includes: a first elastic conductive element and a second elastic conductive element; the first elastic conductive element is disposed on the upper edge of the third frequency selective surface structure and contacts the input unit of the portable terminal device, the input unit being located above the motherboard; the second elastic conductive element is disposed on the lower edge of the third frequency selective surface structure and contacts the outer casing of the portable terminal device, thereby sequentially forming a grounding path consisting of the input unit, the first elastic conductive element, the third frequency selective surface structure, the second elastic conductive element, and the outer casing.

[0114] The input unit can be the keyboard surface (C part) of a portable terminal device, and the outer shell can be the D part of a portable terminal device.

[0115] Figure 8 The diagram illustrates the relative positions of the input unit, rear shell, and air inlet / outlet bracket according to an embodiment of this application.

[0116] like Figure 8 As shown, in the portable terminal device, the air inlet / outlet bracket is located between the input unit 810 and the housing 820. Furthermore, in a direction perpendicular to both the length direction (indicated by arrow X) and the thickness direction of the air inlet / outlet bracket, the input unit 810, the air inlet / outlet bracket, and the housing 820 are sequentially arranged inside the portable terminal device.

[0117] Thus, the first elastic conductive element disposed on the upper edge 830 of the third frequency selection surface structure 330 contacts the input unit 810, and the second elastic conductive element disposed on the lower edge 840 of the third frequency selection surface structure 330 contacts the housing 820, so that a grounding path can be formed based on the first elastic conductive element and the second elastic conductive element, comprising the input unit 810, the first elastic conductive element, the third frequency selection surface structure 330, the second elastic conductive element and the housing 820.

[0118] The upper and lower edges of the third frequency selective surface structure refer to the two ends of the third frequency selective surface structure in directions perpendicular to both the length and thickness directions of the air inlet / outlet bracket, such as... Figure 8 The upper edge 830 and the lower edge 840 are shown.

[0119] In one embodiment, the first and second elastic conductive elements can be conductive foam. Furthermore, the thickness of the first and second elastic conductive elements should ensure sufficient contact between them and the input unit and the housing, respectively, thereby ensuring adequate grounding of the third frequency selective surface structure to form a good electrical connection.

[0120] Therefore, based on the third frequency selection, the upper and lower edges of the surface structure are grounded to parts C and D through the first and second elastic conductive elements, thus forming a good electrical connection.

[0121] Based on the above, the third frequency selective surface structure located in the middle area of ​​the second surface of the air inlet / outlet bracket shares a grounding path with the antenna located on the first surface of the air inlet / outlet bracket. This shared grounding path can be used as part of the third frequency selective surface structure or as a grounding extension of the antenna, thereby avoiding any impact on the antenna performance.

[0122] In one embodiment, the antenna is disposed on the first surface of the air inlet / outlet bracket. The first surface of the air inlet / outlet bracket also has a first frequency selective surface structure and a second frequency selective surface structure disposed on both sides along its length. Specifically, the antenna can be disposed as follows: Figure 3 In region 350 of the first surface 210 of the air inlet / outlet bracket shown, for example, along the length of the air inlet / outlet bracket (in the direction indicated by arrow X), the first frequency selection surface structure and the end of the antenna that are close to each other are 10 mm apart, and the second frequency selection surface structure and the end of the antenna that are close to each other are also 10 mm apart. This makes the openings of the heat dissipation holes on the first surface of the air inlet / outlet bracket smaller, ensuring ventilation while preventing noise leakage. Specifically, the antenna provided on the first surface can cover the heat dissipation holes on the first surface, thereby making the exposed openings of the heat dissipation holes in the area of ​​the first surface other than the first and second frequency selection surface structures smaller.

[0123] According to embodiments of this application, the upper and lower edges of the third frequency selective surface structure are grounded to the input unit and the housing via a first elastic conductive element and a second elastic conductive element, forming a good electrical connection. This shared grounding path can serve as an extension of the antenna, improving antenna efficiency and enhancing the filtering effect of the third frequency selective surface structure. Simultaneously, the shared grounding path allows the third frequency selective surface structure and the antenna to be electrically coordinated, avoiding mutual interference.

[0124] Based on the above, in the noise shielding structure of this application, the antenna and the FSS structure coexist in a very small space. Therefore, the relationship between the antenna and the FSS structure can be summarized as: "Both isolation and cooperation are necessary."

[0125] Regarding the spatial position between the antenna and the FSS structure, the antenna radiation requires a "clearance zone" to ensure that its current distribution is not disrupted. The FSS structure, on the other hand, needs to be as close to the antenna as possible to intercept noise propagation in advance. Therefore, this application divides the FSS into two structures: one located on both sides of the first surface of the air inlet / outlet bracket and the other located in the middle of the second surface. The third frequency selection surface structure is directly integrated with the antenna ground as an extension of the antenna ground, avoiding the introduction of new resonators that could interfere with the antenna. The first and second frequency selection surface structures are set approximately 10 mm from the antenna. This 10 mm distance is a balance point determined through simulation experiments, which achieves near-field noise suppression while minimizing the impact on the antenna pattern.

[0126] Regarding the shared grounding of the antenna and the third frequency selective surface structure, the antenna requires a low-impedance, continuous ground plane to ensure efficiency, and the FSS requires good grounding to form an effective resonance and current dissipation path. Therefore, the third frequency selective surface structure of this application is physically connected to the antenna ground and connected to the C and D components through elastic conductive elements, which provides a larger grounding area for the antenna and improves efficiency; provides a stable grounding for the FSS and enhances filtering; and avoids complex coupling between two independent grounding paths.

[0127] For frequency planning of antennas and FSS structures, the antenna needs to operate efficiently in a preset frequency band (such as WiFi 2.4G / 5G bands), and the FSS needs to generate high suppression in a preset frequency band (such as WiFi 2.4G bands). Therefore, this application uses simulation to precisely tune the dimensions of the first frequency selection surface structure, the second frequency selection surface structure, and the third frequency selection surface structure, so that their resonant points fall precisely on noise frequencies outside the antenna's operating frequency band (such as characteristic interference points in the 2.4GHz band). This makes the FSS "transparent" to the antenna signal and "opaque" only to out-of-band noise.

[0128] According to an embodiment of this application, at least one end of the air inlet / outlet bracket along its length is provided with a mounting portion, and the air inlet / outlet bracket is connected to the heat dissipation fins through the mounting portion; the gap between the air inlet / outlet bracket and the heat dissipation fins is configured to be less than the critical leakage distance of noise in a preset frequency band.

[0129] The mounting section is used to install the heat dissipation fins onto the air inlet and outlet brackets.

[0130] In one embodiment, in addition to the FSS structure, the left and right sides of the air inlet / outlet bracket also have THM heat dissipation fins distributed on both sides. Specifically, the heat dissipation fins can be configured as follows: Figure 3 Areas 340 and 360 are shown. The heat dissipation fins can be mounted on the air inlet and outlet brackets via the mounting parts.

[0131] Since the heat sink fins also generate noise during the heat dissipation process, and sound waves have the ability to bypass obstacles and propagate through narrow gaps, this noise may leak through the gap between the air inlet / outlet bracket and the heat sink fins, thereby affecting the antenna performance.

[0132] Therefore, the gap between the air inlet / outlet bracket and the heat dissipation fins is configured to be less than the critical leakage distance of noise in the preset frequency band.

[0133] In one embodiment, the critical leakage distance is based on 1 / 10 of the wavelength of the noise.

[0134] The preset frequency band is determined based on the antenna operating frequency band in the portable terminal device. For example, the preset frequency band may include frequency bands such as 2.4~2.484GHz, 5.15~5.825GHz, and 5.925~7.125GHz.

[0135] According to an embodiment of this application, since the heat dissipation fins are distributed on both sides of the air inlet and outlet bracket, the gap between the air inlet and outlet bracket and the heat dissipation fins needs to be configured to be less than the critical leakage distance of noise in a preset frequency band, so that the air inlet and outlet bracket and the heat dissipation fins are compactly configured, reducing gaps, thereby making it difficult for sound waves to form an effective propagation path, thereby avoiding noise leakage.

[0136] Frequency-selective surface structures rely on "electromagnetic resonance" rather than "physical obstruction." When electromagnetic waves of a specific frequency (such as 2.4 GHz) reach the surface of the FSS, they excite structural resonance, forming a surface current that reflects or dissipates the energy, while electromagnetic waves (or air) of other frequencies can pass through the FSS structure almost unimpeded.

[0137] Figure 9 The illustration shows a simulation diagram of the current distribution on the first surface of the air inlet / outlet bracket in the noise shielding structure according to an embodiment of this application.

[0138] like Figure 9 As shown, for the first frequency selection surface structure and the second frequency selection surface structure of the left and right sides of the first surface of the air inlet and outlet bracket, most of the noise in the preset frequency band is concentrated in the two sides of the first surface.

[0139] Figure 10 The illustration shows a simulation diagram of the current distribution on the second surface of the air inlet / outlet bracket in the noise shielding structure according to an embodiment of this application.

[0140] like Figure 10As shown, for the third frequency selection surface structure of the middle area of ​​the second surface of the air inlet and outlet bracket, most of the noise of the preset frequency band is concentrated in the middle area of ​​the second surface.

[0141] Therefore, through Figure 9 and Figure 10 As shown, most of the noise energy in the preset frequency band is concentrated in the FSS structure, which blocks the energy in the preset frequency band and achieves the effect of noise suppression.

[0142] Based on the above, the main parameters affecting FSS performance include the FSS structure trace length, width, and shape. Given that the laptop noise distribution is at 2.4 GHz, the design is based on the 2.4 GHz wavelength, and the optimal solution is found through extensive simulations (the FSS structure shape and size resonate with the 2.4 GHz frequency band, causing the 2.4 GHz energy to be confined to the FSS surface, forming a surface current such as...). Figure 9 and Figure 10 As shown in the figure, the two side FSSs and the middle FSS are considered as a whole on the plane, which blocks the noise propagation path like a metal partition wall.

[0143] For the performance verification of the antenna and FSS, the antenna needs to be verified through whole-system testing to ensure antenna efficiency and no radiation pattern degradation. The FSS structure needs to be verified to achieve a noise suppression effect of less than -20dB. Therefore, this application designs the air inlet and outlet bracket through co-simulation and experimental iteration. The process is as follows: preliminary antenna design, introduction of FSS structure, full-wave co-simulation (to view S-parameters, current distribution, and radiation pattern), adjustment of FSS shape / position, sample preparation, simultaneous testing of antenna performance and noise suppression effect on the Tooling whole-system, and fine-tuning to balance.

[0144] Specifically, the first step is to define the frequency band for the FSS structure filtering, using the 2.4GHz band as an example for design simulation research. The FSS structure is divided into two parts (a middle area and two side areas). The middle area is close to the antenna and shares the antenna's ground plane. When designing the FSS structure, it's crucial to ensure that antenna performance is not affected. The distance between the side areas and the antenna is approximately 10mm, ensuring that the opening is small enough to prevent noise from passing through without compromising antenna performance. During the simulation design process, parameters such as the FSS perimeter, shape, and width are meticulously optimized to find the optimal solution. It's also necessary to confirm with the ME / antenna manufacturer whether the rigid parameters of the bracket's appearance meet the standards and whether the manufacturing process is feasible.

[0145] Figure 11 The diagram illustrates the frequency response of a noise shielding structure according to an embodiment of this application for a preset frequency band.

[0146] like Figure 11As shown, for the preset frequency band 2.4GHz~2.5GHz, the average frequency response is -20dB. This indicates that the combined effect of the non-plane FSS in the noise frequency structure achieves an average suppression effect of -20dB in the 2.4GHz~2.5GHz band. Furthermore, since the WiFi 2.4GHz band is between 2.4GHz and 2.484GHz, it completely covers the WiFi 2.4GHz band, thus suppressing noise transmission within this band. The frequency response can be used to characterize the noise suppression effect.

[0147] In one embodiment, by setting the shape and size of the metal conductive pattern of the FSS structure, the reflection and transmission of electromagnetic waves can be controlled, thereby achieving electromagnetic wave filtering in a specific frequency band.

[0148] Figure 12 The schematic diagram illustrates the frequency response of the air inlet / outlet bracket without FSS structure according to an embodiment of this application for a preset frequency band.

[0149] based on Figure 11 and Figure 12 Simulation results of the non-surface FSS structure show that the FSS metamaterial structure has a good suppression effect on WiFi 2.4G frequency band noise. The results show that the combination of frequency selective surface structure and air inlet / outlet bracket provides a theoretical basis, which can successfully suppress the transmission of transmission signals in a certain frequency band and block RF noise without affecting the THM opening ratio.

[0150] Therefore, the FSS structure, through precisely designed spatial coupling and resonance effects, can achieve superior frequency selectivity, wider bandwidth, steeper roll-off, and stronger out-of-band rejection, thus performing better in filtering and denoising applications.

[0151] Figure 13 The diagram illustrates the impact of the FSS-added structure and the non-FSS-added structure on antenna performance according to embodiments of this application.

[0152] like Figure 13 As shown, the antenna performance was actually debugged on the Tooling system. The impact of adding and not adding FSS on antenna performance (open and pad modes) was comprehensively evaluated. From the actual test structure in open and pad modes, the impact of adding and not adding FSS on the antenna is basically around 0.2, and the impact on antenna efficiency is negligible.

[0153] Therefore, the comparison of the air inlet and outlet brackets without FSS shows that adding FSS significantly improves the insertion loss in this frequency band, verifying its filtering effectiveness.

[0154] Based on the above, the frequency selective surface structures disposed on the first and second surfaces in the noise shielding structure of this application must be arranged in a non-planar manner. Specifically, the first and second frequency selective surface structures are disposed on both sides of the air inlet / outlet bracket along the length direction, and the third frequency selective surface structure is disposed in the middle area of ​​the air inlet / outlet bracket along the length direction. However, the first, second, and third frequency selective surface structures differ in shape, size, and layout, but form an overall barrier through electromagnetic coupling and structural grounding.

[0155] In one embodiment, for noise in a preset frequency band to be shielded by the noise shielding structure, the non-planar frequency selective surface structure in the noise shielding structure can achieve a resonant effect at a preset frequency (such as the 2.4 GHz band) through precise design (simulation experiment) spatial coupling. This causes the electromagnetic energy of the preset frequency band to be mainly concentrated on the surface of the frequency selective surface structure to form a surface current, thereby blocking noise propagation. Furthermore, due to the non-planar design of the frequency selective surface structure in the noise shielding structure of this application, a wider stopband, a steeper roll-off, and stronger out-of-band rejection can be achieved through the coupling of the two different structures.

[0156] Based on the above, the noise shielding structure of this application abandons the traditional "shielding" approach of relying on continuous solid material coverage to reflect electromagnetic waves, and instead adopts the "intelligent filtering" concept of frequency selective surfaces (FSS). Based on this, the noise shielding structure of this application directly addresses and successfully resolves the long-standing fundamental contradiction in laptop design between "electromagnetic shielding (small openings) and heat dissipation efficiency (large openings)," enabling efficient suppression of electromagnetic noise in specific frequency bands while maintaining a high physical aperture ratio.

[0157] Furthermore, the noise shielding structure of this application features different FSS patterns on the front (first surface) and back (second surface) of a single air inlet / outlet bracket, forming a "three-dimensional electromagnetic filter cavity" that encloses the ventilation duct. This effectively prevents noise diffraction leakage, representing a significant upgrade from single-sided or double-sided isomorphic FSS. The unit patterns of the FSS structure employ aperiodic and irregular structures, breaking through the theoretical limitations of traditional FSS relying on infinite periodic arrays. Based on the actual irregular installation space and asymmetrical noise source / antenna layout, it adopts an "aperiodic" arrangement and optimized irregular units (such as specific rectangular ring variants). This allows the FSS to fit closely to complex real structures like a "custom jigsaw puzzle," achieving optimal allocation of shielding resources.

[0158] The noise shielding structure of this application integrates the FSS structure and the antenna with a common ground and substrate (same LDS support). This is not simply placing two independent components together, but achieving performance isolation and functional gain through deep electrical and structural integration. Specifically, performance isolation: through precise simulation and partitioning design, the resonant frequency of the FSS is ensured to accurately suppress noise while remaining "transparent" to the antenna's operating frequency band, resulting in minimal impact on antenna efficiency (<0.2dB) in actual measurements. Functional gain: the intermediate FSS structure (third frequency selective surface structure) acts as an extension of the antenna ground, potentially improving the antenna grounding performance and transforming a "potential interference source" into a "beneficial supplementary ground." Thus, the noise shielding structure of this application is obtained through dynamic trade-offs and collaborative optimization design among three key indicators: antenna performance, filtering depth, and aperture ratio.

[0159] According to embodiments of this application, the FSS is manufactured directly using readily available antenna LDS (laser direct forming) technology, eliminating the need for additional processes or molds and achieving "zero" additional manufacturing costs. This represents a significant cost advantage compared to traditional solutions that add absorbing materials (MEsolution) or separate metal components. Furthermore, this application establishes a design process that can be quickly adapted to different projects. Specifically, by adjusting the FSS unit graphic size, designs can be tailored to specific noise frequency bands (such as WiFi 2.4G, 5G, or specific clock harmonics) for different projects. The aperiodic nature of the FSS structure allows it to flexibly adapt to the inlet / outlet shapes and internal layouts of different products.

[0160] Based on this, this application not only solves the problem but also brings positive benefits: while successfully suppressing noise (-20dB), it increases the heat dissipation opening ratio to a level that traditional barrier wall solutions cannot achieve, thereby directly contributing to the improvement of overall power consumption (approximately 2W) and realizing a net gain in system performance. Furthermore, the position of the FSS structure can be flexibly moved according to the antenna location, and different metal conductive patterns of the FSS structure can be designed for different frequency bands of RF noise.

[0161] Based on the foregoing, this application also discloses a portable terminal device. This portable terminal device includes, for example: Figure 3 The noise shielding structure shown is located between the motherboard and the antenna of the portable terminal device.

[0162] Those skilled in the art will understand that the features described in the various embodiments of this application can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in this application. In particular, the features described in the various embodiments of this application can be combined and / or combined in various ways without departing from the spirit and teachings of this application. All such combinations and / or combinations fall within the scope of this application.

[0163] The embodiments of this application have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of this application. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Without departing from the scope of this application, those skilled in the art can make various substitutions and modifications, all of which should fall within the scope of this application.

Claims

1. A noise shielding structure, characterized in that, The noise shielding structure includes: The air inlet and outlet bracket is configured as a plate structure, having a first surface and a second surface facing away from each other, and heat dissipation holes penetrating the first surface and the second surface; The first frequency selection surface structure and the second frequency selection surface structure are respectively disposed on both sides of the first surface along the length direction of the air inlet and outlet bracket; The third frequency selection surface structure is located in the middle region of the second surface; In the projection with the first surface as the projection plane and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the third frequency selection surface structure is misaligned with the projection of the first frequency selection surface and the projection of the second frequency selection surface. Furthermore, the sum of the coverage areas of the first frequency selection surface structure, the second frequency selection surface structure, and the third frequency selection surface structure along the length direction of the air inlet / outlet bracket matches the length of the air inlet / outlet bracket.

2. The noise shielding structure according to claim 1, characterized in that, The first frequency selective surface structure, the second frequency selective surface structure, and the third frequency selective surface structure all have metallic conductive patterns. The metallic conductive patterns include at least two unit patterns arranged along the length direction of the air inlet / outlet bracket, and each unit pattern has a through hole.

3. The noise shielding structure according to claim 2, characterized in that, The unit pattern is configured as at least one of a rectangular ring structure, a cross structure, and an I-shaped structure.

4. The noise shielding structure according to claim 2, characterized in that, In the projection with the first surface as the projection plane and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the heat dissipation hole coincides with the projection of the through hole in the third frequency selection surface structure.

5. The noise shielding structure according to claim 1, characterized in that, The antenna of the portable terminal device is disposed on the first surface of the air inlet / outlet bracket; Furthermore, the second surface is configured to face the motherboard of the portable terminal device.

6. The noise shielding structure according to claim 5, characterized in that, In the projection with the first surface as the projection plane and the thickness direction of the air inlet / outlet bracket as the projection direction, the projection of the motherboard coincides with the projection of the air inlet / outlet bracket.

7. The noise shielding structure according to claim 5, characterized in that, The third frequency selective surface structure is configured to share a ground path with the ground portion of the antenna.

8. The noise shielding structure according to claim 7, characterized in that, Also includes: First elastic conductive element and second elastic conductive element; The first elastic conductive element is disposed on the upper edge of the third frequency selective surface structure and is in contact with the input unit of the portable terminal device, the input unit being located above the motherboard; The second elastic conductive element is disposed at the lower edge of the third frequency selective surface structure and is in contact with the housing of the portable terminal device to form a grounding path sequentially consisting of the input unit, the first elastic conductive element, the third frequency selective surface structure, the second elastic conductive element, and the housing.

9. The noise shielding structure according to claim 1, characterized in that, The air inlet / outlet bracket is provided with a mounting part at least one end along its length, and the air inlet / outlet bracket is connected to the heat dissipation fins through the mounting part. The gap between the air inlet / outlet bracket and the heat dissipation fins is configured to be less than the critical leakage distance of noise in a preset frequency band.

10. A portable terminal device, characterized in that, The portable terminal device includes a noise shielding structure as described in any one of claims 1 to 9; The noise shielding structure is disposed between the motherboard and the antenna of the portable terminal device.

Images