Electronic device

Abstract

The application discloses an electronic device, and relates to the technical field of electronic products. The electronic device comprises a non-metal appearance piece, an antenna radiation sheet and an electromagnetic wave conversion piece. The antenna radiation sheet is arranged opposite to the non-metal appearance piece, and a first gap is formed between the antenna radiation sheet and the non-metal appearance piece. The electromagnetic wave conversion piece is embedded in the non-metal appearance piece. The electromagnetic wave conversion piece comprises a metal base arranged opposite to the antenna radiation sheet, and a metal column protruding from a side of the metal base opposite to the antenna radiation sheet. The metal base is coupled with the antenna radiation sheet.

Description

Technical Field

[0001] This application relates to the field of electronic product technology, specifically to an electronic device. Background Technology

[0002] In related technologies, mobile terminal devices such as mobile phones and tablets typically achieve wireless communication by transmitting and receiving electromagnetic waves through terminal antennas. When using these devices, users are usually exposed to an electromagnetic environment at close range. Since human tissue is a lossy medium, it will inevitably absorb some of the electromagnetic energy radiated by the antenna. Currently, the industry widely uses Specific Absorption Rate (SAR) as an indicator to assess the dose of electromagnetic radiation absorbed by the human body, and various countries and regions have imposed strict regulations on the SAR value of terminal devices. With the increasing number of antennas required for 5G terminal devices, the industry typically deploys 1-2 flexible printed circuit board (FPC) antennas specifically for 5G N78 / N79 band radiation within electronic devices. However, excessively high SAR can easily occur in the main radiation direction of these antennas. Summary of the Invention

[0003] This application provides an electronic device that can solve the problem of excessively high backscatter SAR in terminal devices in related technologies.

[0004] In a first aspect, an electronic device is provided, including a non-metallic exterior component, an antenna radiating plate, and an electromagnetic wave conversion component, wherein the antenna radiating plate is disposed opposite to the non-metallic exterior component, and a first gap is formed between the antenna radiating plate and the non-metallic exterior component;

[0005] The electromagnetic wave converter is embedded in the non-metallic exterior component. The electromagnetic wave converter includes: a metal substrate disposed opposite to the antenna radiating plate, and a metal post protruding from the side of the metal substrate opposite to the antenna radiating plate; wherein the metal substrate is coupled to the antenna radiating plate.

[0006] In this embodiment, since the direction of maximum radiation intensity of the antenna radiating plate is towards the human tissue, and the radiated electric field is parallel to the human tissue, a strong tangential electric field will be generated in the human tissue. Therefore, by setting an electromagnetic wave conversion component opposite to the antenna radiating plate in a non-metallic exterior component, the electromagnetic wave conversion component includes: a metal substrate disposed opposite to the antenna radiating plate, and a metal column protruding from the side of the metal substrate opposite to the antenna radiating plate. The metal substrate is coupled to the antenna radiating plate, so the energy coupled to the substrate can be dispersed to the metal column. The direction of the current in the metal column is perpendicular to the human tissue, and the main polarization direction of its radiated electric field is normal to the human tissue. This can convert part of the radiated electric field of the metal radiating plate from tangential to normal, thereby reducing the tangential electric field strength generated by the antenna radiating plate in the human tissue, which is beneficial to reducing the SAR value in the main radiation direction of the antenna. Attached Figure Description

[0007] Figure 1 This is one of the cross-sectional schematic diagrams of the FPC antenna in some embodiments of this application;

[0008] Figure 2A This is one of the top views of the location of the FPC antenna and electromagnetic wave converter in some embodiments of this application;

[0009] Figure 2B This is a side view of an electromagnetic wave converter in some embodiments of this application;

[0010] Figure 3 A is a schematic diagram of the electric field radiated by the FPC antenna at a conventional battery cover.

[0011] Figure 3 B is a schematic diagram of the antenna radiation electric field at the non-metallic battery cover of the FPC antenna in the embodiment of this application;

[0012] Figure 4A This is a schematic diagram of the structure when the non-metallic exterior component and the electromagnetic wave conversion component are connected in some embodiments of this application;

[0013] Figure 4B This is the second cross-sectional schematic diagram of the FPC antenna in some embodiments of this application;

[0014] Figure 5A This is a top view of the FPC antenna connected to the ground plane in some embodiments of this application;

[0015] Figure 5B yes Figure 5A Side view;

[0016] Figure 6A yes Figure 2A One of the schematic diagrams of current distribution of the FPC antenna in the illustrated embodiment;

[0017] Figure 6B yes Figure 2A The second schematic diagram of the current distribution of the FPC antenna in the illustrated embodiment;

[0018] Figure 7 yes Figure 2A A schematic diagram of the simulated current distribution of the FPC antenna in the illustrated embodiment.

[0019] Figure 8 This is a schematic diagram of the radiated electric field characteristics of a current element in the near field;

[0020] Figure 9A yes Figure 2A The diagram shown illustrates the current distribution in the electromagnetic wave converter during antenna operation in the embodiment shown.

[0021] Figure 9B yes Figure 2A A schematic diagram of the simulated current distribution in the electromagnetic wave converter when the antenna is working in the embodiment shown;

[0022] Figure 10 This is a schematic diagram of the simulation results of the electric field in the back 5mm plane with an FPC antenna loaded onto a conventional battery cover;

[0023] Figure 11 It is an FPC antenna loading Figure 2A A schematic diagram of the simulation results of the electric field on the back of the 5mm plane of the non-metallic exterior component in the embodiment shown.

[0024] Figure 12 These are the simulation results of a 5mm Body-SAR image with an FPC antenna loaded with a conventional battery cover, facing away from the camera.

[0025] Figure 13 It is an FPC antenna loading Figure 2A The back-facing 5mm Body-SAR simulation results of the non-metallic exterior component in the illustrated embodiment;

[0026] Figure 14 yes Figure 2A A schematic diagram comparing the reflection coefficients of the illustrated embodiment and a conventional battery cover antenna;

[0027] Figure 15 yes Figure 2A The diagram shows a comparison of the efficiency of the embodiment and the conventional battery cover antenna.

[0028] Figure 16 This is a second top view of the location of the FPC antenna and electromagnetic wave converter in some embodiments of this application;

[0029] Figure 17 yes Figure 16 The illustrated embodiments and Figure 2AA schematic diagram comparing the antenna reflection coefficients of the embodiments shown;

[0030] Figure 18 yes Figure 16 The illustrated embodiments and Figure 2A A schematic diagram comparing the antenna efficiency of the embodiments shown;

[0031] Figure 19 yes Figure 16 The diagram shows the simulation results of the FPC antenna facing away from the 5mm Body-SAR in the embodiment shown. Detailed Implementation

[0032] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0033] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same class, not limited in number; for example, the first object can be one or more. Furthermore, "or" in this application indicates at least one of the connected objects. For example, the scope of protection for "A or B" covers at least three scenarios: Scenario 1: including A but not B; Scenario 2: including B but not A; Scenario 3: including both A and B. In addition, the terms "A and / or B," "at least one of A and B," and "at least one of A or B" also cover at least the above three scenarios. The character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0034] The electronic device provided in the embodiments of this application will be described in detail below with reference to the accompanying drawings and through some embodiments and application scenarios.

[0035] Please see Figure 1 , Figure 2A and Figure 2B This application provides an electronic device, including a non-metallic exterior component 200, an antenna radiating plate 300, and an electromagnetic wave converter 400. The antenna radiating plate 300 is disposed opposite to the non-metallic exterior component 200, and a first gap 600 is formed between the antenna radiating plate 300 and the non-metallic exterior component 200.

[0036] The electromagnetic wave converter 400 is embedded in the non-metallic exterior part 200. The electromagnetic wave converter 400 includes: a metal substrate 410 disposed opposite to the antenna radiating plate 300, and a metal post 420 protruding from the side of the metal substrate 410 opposite to the antenna radiating plate 300; wherein the metal substrate 410 is coupled to the antenna radiating plate 300.

[0037] The non-metallic exterior component 200 can be various exterior components of an electronic device, such as a back cover or a frame structure. When the non-metallic exterior component 200 is a back cover, one end face of the antenna radiating plate 300 can face the inner side of the back cover. When the non-metallic exterior component 200 is a frame structure of an electronic device, one end face of the antenna radiating plate 300 can face the inner side of the frame. The non-metallic exterior component 200 can be made of various non-metallic materials, such as glass or plastic. This embodiment uses a glass back cover as an example to further explain the structure of the electronic device.

[0038] When the non-metallic exterior component 200 is a glass back cover, the antenna radiating plate 300 can be a radiator of an FPC antenna mounted on the motherboard bracket of an electronic device. It is understood that the antenna radiating plate 300 may include a feed point 311 and a ground point. The ground point is electrically connected to the ground plane 100, and the feed point 311 can be electrically connected to a radio frequency (RF) circuit in the electronic device. This RF circuit is deployed on various circuit boards within the electronic device; for example, it can be deployed on the motherboard of the electronic device. The ground plane 100 can be the main ground of the electronic device, specifically, it can be various types of metal plates.

[0039] In some embodiments of this application, the metal pillar 420 can be completely housed within the non-metallic outer surface component 200, in which case the metal pillar 420 will not protrude from the surface of the non-metallic outer surface component 200. In some embodiments of this application, the metal pillar 420 may also include a protruding portion extending from one side of the outer surface of the non-metallic outer surface component 200, in which case the metal pillar 420 protrudes from the surface of the non-metallic outer surface component 200. The electromagnetic wave converter 400 can be used to convert part of the electromagnetic waves from the antenna radiating plate 300 from a tangential direction relative to human tissue to a normal direction relative to human tissue. The shape of the metal substrate 410 can be configured as needed, for example, it can be strip-shaped, cross-shaped, ring-shaped, etc. The length of the metal pillar 420 can be greater than or equal to 1 mm.

[0040] The operating frequency band of the aforementioned antenna radiator can be set as needed, for example, it can be the N78 band or the N79 band. In this embodiment, taking the N78 band as the operating frequency band of the antenna radiator as an example, the structure of the electronic device will be further explained.

[0041] like Figure 6A and Figure 6B The diagram shown illustrates the current distribution of the FPC antenna operating in the N78 frequency band according to an embodiment of this application. Figure 7 This is the antenna current distribution simulated in CST software. The antenna radiating plate 300 operates in a quarter-wavelength mode current from the open-circuit terminal to the grounding metal plate 710. At this time, the current in the radiating plate and the metal ground plate participates in the radiation as the main current, parallel to the back-facing human tissue.

[0042] At this point, the total electric field radiated by the FPC antenna can be considered as the superposition of countless current elements parallel to human tissue in the xoy plane radiating in the near field. According to theoretical derivation, the radiation characteristics of the current elements in the near field are as follows: Figure 8 As shown, the antenna has zero radiation points at both ends of the current element, where the radiation intensity is weakest; it has maximum radiation intensity at both sides, and the polarization direction of the radiated electric field is parallel to the direction of the current element. Therefore, the relative position of the antenna current to the human tissue will affect the antenna's SAR characteristics. A current element parallel to the human tissue has maximum radiation intensity in the direction of the human tissue, and the polarization of the radiated electric field is parallel to the human tissue, generating a strong tangential electric field at the human tissue-air boundary, which will lead to a high SAR value inside the human tissue. Conversely, a current element perpendicular to the human tissue has zero radiation points at both ends, and the maximum polarization of the radiated electric field is perpendicular to the human tissue, making it difficult for the electric field to penetrate the human body, thus reducing the SAR value. The FPC antenna's main radiated current is parallel to the human tissue in the direction of the battery cover, thus producing a high backscatter SAR value.

[0043] like Figure 3 Figure A shows a schematic diagram illustrating the modulation of the antenna's radiated electric field by a conventional battery cover. Figure 3 Figure B shows a schematic diagram of the non-metallic exterior component 200 with electromagnetic wave conversion component 400 controlling the radiated electric field of the antenna in an embodiment of this application. The dashed arrows represent the antenna current, and the solid arrows represent the radiated electric field. When the FPC antenna on the motherboard bracket is working, since the antenna current is parallel to the back of the human tissue, the radiated electric field is mainly a tangential electric field component parallel to the plane of the human tissue.

[0044] For conventional battery covers, the main material is usually a glass dielectric with a dielectric constant of about 7.2. The electric field radiated by the antenna does not undergo a significant polarization change when passing through the battery cover. When it reaches the boundary between the air and human tissue, the main component is still the tangential electric field component. According to the electromagnetic field boundary condition, the electric field of the tangential component is approximately continuous at the boundary of human tissue. Therefore, the electric field radiated by the antenna can smoothly enter the human body. The magnitude of the SAR value depends on the electric field strength inside the human tissue, which leads to the FPC antenna producing a high back SAR value.

[0045] This application embodiment designs a specific electromagnetic wave conversion component 400 on the non-metallic exterior component 200 above the FPC antenna, thereby enabling the non-metallic exterior component 200 to possess a certain electromagnetic wave polarization conversion function. For example... Figure 3 As shown in Figure B, the electric field radiated by the antenna relative to human tissue, which is tangential, can be partially converted into a normal electric field, thus weakening the tangential electric field component of the antenna. According to the electromagnetic field boundary conditions, the amplitude of the normal electric field attenuates by more than 30 times on both sides of the air-human tissue boundary. Therefore, it can be considered that the normal electric field component is difficult to penetrate the human body. The weakening of the tangential electric field entering the human tissue thus reduces the SAR value of the antenna on the back side.

[0046] This application embodiment reduces the backscattered SAR value of the FPC antenna by incorporating an electromagnetic wave converter 400 on the non-metallic exterior component 200 of the electronic device. This reduces the antenna conducted power drop caused by the high backscattered SAR value of the FPC antenna on the traditional motherboard bracket, thereby improving the antenna TRP and the overall communication performance of the electronic device.

[0047] This application addresses the problem that traditional frame antenna SAR reduction schemes are difficult to apply. By designing a SAR reduction structure on the non-metallic exterior component 200, the SAR reduction structure and the non-metallic exterior component 200 are integrated. Compared with traditional SAR reduction schemes such as loading materials inside the device or loading parasitic branches around the antenna, this does not require occupying the compact internal design space of the terminal device, and can improve the overall integration of the terminal device.

[0048] In this embodiment, the back SAR value of the FPC antenna on the motherboard bracket can be reduced without modifying the antenna body. The SAR-reducing battery back cover does not affect the design and radiation performance of other antennas inside the mobile phone.

[0049] In this embodiment, since the direction of maximum radiation intensity of the antenna radiating plate 300 is in the direction of human tissue, and the radiated electric field is parallel to the human tissue, a strong tangential electric field will be generated in the human tissue. Therefore, by providing an electromagnetic wave converter 400 opposite to the antenna radiating plate 300 in the non-metallic exterior component 200, the electromagnetic wave converter 400 includes: a metal substrate 410 opposite to the antenna radiating plate 300, and a metal pillar 420 protruding from the side of the metal substrate 410 opposite to the antenna radiating plate 300. The metal substrate 410 is coupled to the antenna radiating plate 300, so the energy coupled to the substrate can be dispersed to the metal pillar 420. The direction of the current in the metal pillar 420 is perpendicular to the human tissue, and the main polarization direction of its radiated electric field is normal to the human tissue. This can convert part of the radiated electric field of the metal radiating plate from tangential to normal, thereby reducing the tangential electric field strength generated by the antenna radiating plate 300 in the human tissue, which is beneficial to the SAR value in the main radiation direction of the antenna.

[0050] Optionally, the metal substrate 410 includes a first metal strip 411 and a second metal strip 412 arranged in a cross pattern. The first metal strip 411 has a plurality of metal pillars 420 on the side opposite to the antenna radiating sheet 300, and the second metal strip 412 has a plurality of metal pillars 420 on the side opposite to the antenna radiating sheet 300.

[0051] The first metal strip 411 may be set at an angle to the second metal strip 412. The size of the angle between the first metal strip 411 and the second metal strip 412 may be set as needed. For example, in some embodiments of this application, the angle between the first metal strip 411 and the second metal strip 412 may be in the range of 45° to 135°.

[0052] In this embodiment, by including a first metal strip 411 and a second metal strip 412 arranged in a cross pattern in the metal substrate 410, the first metal strip 411 and the second metal strip 412 can respectively sense the current in the x and y directions of the antenna radiating plate 300 compared to the branches of the coupling metal strip in a single direction, thereby achieving more sufficient excitation to enhance the induced current on the electromagnetic wave converter 400. This allows more electromagnetic waves to be converted from tangential to normal relative to human tissue, further reducing the tangential electric field strength generated by the antenna radiating plate 300 in human tissue, thereby reducing the antenna SAR value, i.e., reducing the SAR value of the electronic device on the back side.

[0053] Optionally, the length of the first metal strip 411 is matched with half the operating wavelength of the antenna radiating plate 300, and the length of the second metal strip 412 is matched with half the operating wavelength of the antenna radiating plate 300.

[0054] The fact that the length of the first metal strip 411 matches half of the operating wavelength of the antenna radiating plate 300 can mean that the length of the first metal strip 411 is equal to half of the operating wavelength of the antenna radiating plate 300, or that the length of the first metal strip 411 is a value close to half of the operating wavelength of the antenna radiating plate 300.

[0055] Accordingly, the length of the second metal strip 412 matching half of the operating wavelength of the antenna radiating plate 300 can mean that the length of the second metal strip 412 is equal to half of the operating wavelength of the antenna radiating plate 300, or that the length of the second metal strip 412 is a value near half of the operating wavelength of the antenna radiating plate 300.

[0056] It is understood that the length of the first metal strip 411 and the length of the second metal strip 412 may be equal or unequal. The operating wavelength of the antenna radiating plate 300 may be the dielectric wavelength corresponding to one of the frequency points in the operating frequency band of the antenna radiating plate 300, for example, it may be the dielectric wavelength corresponding to the center frequency point in the operating frequency band of the antenna radiating plate 300.

[0057] In this embodiment, since the length of the first metal strip 411 matches half the operating wavelength of the antenna radiating plate 300, and the length of the second metal strip 412 matches half the operating wavelength of the antenna radiating plate 300, the first metal strip 411 and the second metal strip 412 can generate a resonant frequency of half-wavelength current mode during the operation of the antenna radiating plate 300, making it close to the antenna operating frequency, thus ensuring that the metal strips can sense a strong half-wavelength mode current in the N78 frequency band where the antenna operates.

[0058] Optionally, a plurality of metal pillars 420 disposed on the side of the first metal strip 411 opposite to the antenna radiating plate 300 form a plurality of first pillar groups 430. The plurality of first pillar groups 430 are arranged sequentially at intervals along the length direction of the first metal strip 411. Each first pillar group 430 includes two metal pillars 420, and the two metal pillars 420 in the first pillar group 430 are arranged at intervals along the width direction of the first metal strip 411.

[0059] The multiple metal pillars 420 disposed on the side of the second metal strip 412 opposite to the antenna radiating plate 300 form multiple second pillar groups 440. The multiple second pillar groups 440 are arranged sequentially at intervals along the length direction of the second metal strip 412. Each second pillar group 440 includes two metal pillars 420, and the two metal pillars 420 in the second pillar group 440 are arranged at intervals along the width direction of the second metal strip 412.

[0060] In this embodiment, multiple metal pillars 420 disposed on the side of the first metal strip 411 facing away from the antenna radiating plate 300 form multiple first pillar groups 430. These multiple first pillar groups 430 are arranged sequentially at intervals along the length of the first metal strip 411. Each first pillar group 430 includes two metal pillars 420, and the two metal pillars 420 in each first pillar group 430 are arranged at intervals along the width of the first metal strip 411. Multiple metal pillars 420 disposed on the side of the second metal strip 412 facing away from the antenna radiating plate 300 form multiple... The second column group 440 is arranged sequentially at intervals along the length direction of the second metal strip 412. Each second column group 440 includes two metal columns 420, and the two metal columns 420 in the second column group 440 are arranged at intervals along the width direction of the second metal strip 412. This facilitates the deployment of a sufficient number of metal columns 420 on the electromagnetic wave converter 400, thereby improving the current dispersion efficiency of the electromagnetic wave converter 400 and increasing the proportion of normal current perpendicular to human tissue, so as to further reduce the SAR value in the back cover direction of the electronic device.

[0061] Optionally, the metal substrate 410 further includes a first extension branch 413, a second extension branch 414, a third extension branch 415, and a fourth extension branch 416. The first end of the first metal strip 411 is connected to the middle of the first extension branch 413, the second end of the first metal strip 411 is connected to the middle of the second extension branch 414, the first end of the second metal strip 412 is connected to the middle of the third extension branch 415, and the second end of the second metal strip 412 is connected to the middle of the fourth extension branch 416.

[0062] The dimensions of the first extension stub 413 and the second extension stub 414 can be set as needed. These stubs can be used to fine-tune the resonant frequency of the half-wavelength current mode of the first metal strip 411, bringing it close to the antenna's operating frequency. This ensures that the first metal strip 411 can sense a strong half-wavelength current mode in the N78 frequency band where the antenna operates. Correspondingly, the dimensions of the third extension stub 415 and the fourth extension stub 416 can be set as needed. These stubs can also be used to fine-tune the resonant frequency of the half-wavelength current mode of the second metal strip 412, bringing it close to the antenna's operating frequency. This ensures that the second metal strip 412 can sense a strong half-wavelength current mode in the N78 frequency band where the antenna operates.

[0063] In this embodiment, by further including a first extension branch 413, a second extension branch 414, a third extension branch 415, and a fourth extension branch 416 in the metal substrate 410, the first end of the first metal strip 411 is connected to the middle of the first extension branch 413, the second end of the first metal strip 411 is connected to the middle of the second extension branch 414, the first end of the second metal strip 412 is connected to the middle of the third extension branch 415, and the second end of the second metal strip 412 is connected to the middle of the fourth extension branch 416. In this way, the resonant frequency of the half-wavelength current mode of the first metal strip 411 can be finely adjusted by the first extension branch 413 and the second extension branch 414 to make it close to the antenna operating frequency, ensuring that the first metal strip 411 can sense a strong half-wavelength mode current in the N78 frequency band where the antenna operates. Meanwhile, the resonant frequency of the half-wavelength current mode of the second metal strip 412 can be finely adjusted by the third extension stub 415 and the fourth extension stub 416 to make it close to the antenna operating frequency, ensuring that the second metal strip 412 can sense a strong half-wavelength mode current in the N78 frequency band where the antenna is operating.

[0064] Optionally, the first metal strip 411 is perpendicular to the second metal strip 412, and the middle part of the first metal strip 411 coincides with the middle part of the second metal strip 412.

[0065] In this embodiment, since the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is the current strong point of the electromagnetic wave converter 400, by making the first metal strip 411 and the second metal strip 412 perpendicular, and the middle part of the first metal strip 411 and the middle part of the second metal strip 412 coincide, the current on both sides of the middle part of the first metal strip 411 and the current on both sides of the middle part of the second metal strip 412 can be relatively balanced, thereby making the polarization conversion effect of each region of the electromagnetic wave converter 400 relatively uniform.

[0066] Optionally, the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is provided with four metal columns 420 arranged in a rectangular array.

[0067] In some embodiments of this application, the middle part of the first metal strip 411 coincides with the middle part of the second metal strip 412, the first metal strip 411 is perpendicular to the second metal strip 412, and the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is provided with four metal columns 420 arranged in a rectangular array.

[0068] In this embodiment, since the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is the current strong point of the electromagnetic wave converter 400, by setting more dense metal pillars 420 in this area, that is, four metal pillars 420 arranged in a rectangular array are set in the overlapping area 417 of the first metal strip 411 and the second metal strip 412, the conversion efficiency of electromagnetic waves at the current strong point can be further improved.

[0069] Optionally, the first extension branch 413 and the second extension branch 414 are parallel to the second metal strip 412, and the third extension branch 415 and the fourth extension branch 416 are parallel to the first metal strip 411.

[0070] In some embodiments of this application, the middle part of the first metal strip 411 coincides with the middle part of the second metal strip 412, the first metal strip 411 is perpendicular to the second metal strip 412, and the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is provided with four metal columns 420 arranged in a rectangular array; the first extension branch 413 and the second extension branch 414 are respectively parallel to the second metal strip 412, and the third extension branch 415 and the fourth extension branch 416 are respectively parallel to the first metal strip 411.

[0071] The length and cross-sectional dimensions of the first extension branch 413, the second extension branch 414, the third extension branch 415 and the fourth extension branch 416 mentioned above can be the same or nearly the same.

[0072] In this embodiment, by making the first extension branch 413 and the second extension branch 414 parallel to the second metal strip 412, and the third extension branch 415 and the fourth extension branch 416 parallel to the first metal strip 411, the extension branches on both sides of the first metal strip 411 are relatively symmetrical, and the extension branches on both sides of the second metal strip 412 are also relatively symmetrical, which helps to make the polarization conversion effect of each region of the electromagnetic wave converter 400 relatively uniform.

[0073] Optionally, the center of the first rectangular region enclosed by the edge of the electromagnetic wave converter 400 is aligned with the center of the second rectangular region enclosed by the edge of the antenna radiating plate 300, and the two axes of symmetry of the first rectangular region are aligned with the two axes of symmetry of the second rectangular region. The feed point 311 of the antenna radiating plate 300 is located on the first side 310 of the antenna radiating plate 300.

[0074] The first side 310 can be any side of the antenna radiating sheet 300, for example, it can be one side of the antenna radiating sheet 300 along its length.

[0075] In some embodiments of this application, the middle part of the first metal strip 411 coincides with the middle part of the second metal strip 412, the first metal strip 411 is perpendicular to the second metal strip 412, and the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is provided with four metal pillars 420 arranged in a rectangular array; the first extension branch 413 and the second extension branch 414 are parallel to the second metal strip 412, and the third extension branch 415 and the fourth extension branch 416 are parallel to the first metal strip 411; the center of the first rectangular area formed by the edge of the electromagnetic wave converter 400 is aligned with the center of the second rectangular area formed by the edge of the antenna radiating plate 300, and the two axes of symmetry of the first rectangular area are aligned with the two axes of symmetry of the second rectangular area; the feed point 311 of the antenna radiating plate 300 is located on the first side 310 of the antenna radiating plate 300.

[0076] In this embodiment, by aligning the center of the first rectangular region enclosed by the edge of the electromagnetic wave converter 400 with the center of the second rectangular region enclosed by the edge of the antenna radiating plate 300, and aligning the two axes of symmetry of the first rectangular region with the two axes of symmetry of the second rectangular region, it is beneficial to ensure that the electromagnetic wave converter 400 can completely cover the antenna radiating plate 300, so as to achieve a better polarization conversion effect in the rear cover direction.

[0077] Optionally, in the first metal strip 411, a group of first pillars 430 is provided at a first distance from the overlapping area 417 to the end of the first metal strip 411, wherein the overlapping area 417 is the overlapping area of ​​the first metal strip 411 and the second metal strip 412.

[0078] In the second metal strip 412, a set of second column groups 440 is provided at intervals of the first distance from the overlapping area 417 to the end of the second metal strip 412.

[0079] In some embodiments of this application, the middle part of the first metal strip 411 coincides with the middle part of the second metal strip 412, the first metal strip 411 is perpendicular to the second metal strip 412, and the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is provided with four metal pillars 420 arranged in a rectangular array; the first extension branch 413 and the second extension branch 414 are parallel to the second metal strip 412, and the third extension branch 415 and the fourth extension branch 416 are parallel to the first metal strip 411; the center of the first rectangular area formed by the edge of the electromagnetic wave converter 400 is aligned with the center of the second rectangular area formed by the edge of the antenna radiating plate 300, and the two axes of symmetry of the first rectangular area are aligned with the two axes of symmetry of the second rectangular area; the feed point 311 of the antenna radiating plate 300 is located on the first side 310 of the antenna radiating plate 300. In the first metal strip 411, a group of first pillars 430 is provided at a first distance from the overlapping area 417 to the end of the first metal strip 411; in the second metal strip 412, a group of second pillars 440 is provided at a first distance from the overlapping area 417 to the end of the second metal strip 412.

[0080] The range of the first distance can be set as needed; for example, the range of the first distance is 0.5mm to 3mm. Figure 2A In the illustrated embodiment, the first distance is 1.5 mm.

[0081] Figure 4A and Figure 4B This is a schematic diagram of a portion of the structure of an electronic device in an embodiment of this application. From top to bottom along the Z direction, it includes a non-metallic exterior component 200, an electromagnetic wave converter 400, an antenna radiating plate 300 of an FPC antenna, a ground plane 100, and a dielectric substrate 800 at the bottom of the ground plane 100.

[0082] The non-metallic exterior part 200 is made of glass with a dielectric constant of 7.2, and its dimensions are... It is the standard size of a candybar phone battery cover, and its Z-axis distance from the FPC antenna is 0.4mm.

[0083] In the embodiments of this application, the antenna structure is as follows: Figure 5A and Figure 5B As shown, this is a common PIFA antenna form of FPC antenna, which consists of an antenna radiating plate 300, a grounding metal plate 710, a feed metal plate 720, a feed port, a metal ground plane, and a dielectric substrate 800. The feed port feeds the antenna between the feed metal plate 720 and the metal ground plane. The ground plane 100 and the dielectric substrate 800 are both [dimensions missing]. The dielectric material is FR-4 with a dielectric constant of 4.3. The antenna radiating plate 300 has dimensions of 15mm in length (x-direction), 6mm in width (y-direction), and a height of 4mm above the metal ground plane. The feed metal plate 720 and the grounding metal plate 710 are 2mm wide and spaced 2.5mm apart. The antenna operates in the N78 band (3.3-3.8GHz) in 1 / 4 wavelength current mode, where the frequency range of the N78 band is 3.3GHz to 3.8GHz.

[0084] The structure of the electromagnetic wave converter 400 is as follows: Figure 2A and Figure 2B As shown, it is integrated into the glass back cover and consists of three parts: a glass medium, a coupling metal strip printed on the bottom of the medium near the antenna radiating plate 300, and a metal pillar 420 penetrating the glass medium in the Z direction. The electromagnetic wave converter 400 is 16mm long in both the x and y directions and 1mm thick in the Z direction. It is located directly above the FPC antenna radiating plate 300, and the center of the electromagnetic wave converter 400 is aligned with the center of the antenna radiating plate 300 in the Z direction, ensuring that the electromagnetic wave converter 400 can completely cover the antenna radiating plate 300 in the Z direction to achieve better polarization conversion effect in the back cover direction. The distance between the electromagnetic wave converter 400 and the FPC antenna in the Z direction is 0.4mm, which is consistent with the distance between a conventional battery cover and the antenna. The glass medium can reuse the glass back cover of the battery cover. Printed on the bottom plane of the medium are... Figure 2AThe "grid-like cross-shaped" metal strip shown is a cross-shaped structure composed of the first metal strip 411 and the second metal strip 412. The central cross-shaped metal strip has a length of 16mm in both the x and y directions and a width of 1mm. The metal strips on the four sides have a length of 8mm and a width of 0.5mm. Multiple [unclear] sized [unclear] are set on the central cross-shaped metal strip. The metal columns 420 penetrate the entire glass medium in the Z direction. Two columns are arranged side by side as a group, with a column spacing of 0.1mm within the group. The column spacing between the two central groups is 0.1mm, and the spacing between other adjacent groups is 1.5mm. Ten groups of columns are deployed in both the x and y directions.

[0085] In this embodiment of the application, when the FPC antenna operates in the N78 frequency band, the current distribution diagram of the electromagnetic wave converter 400 loaded in the non-metallic outer part 200 is shown below. Figure 6A and Figure 6B As shown, Figure 7 The current distribution diagram simulated in CST software is shown. Through the back view of the current, it can be seen that the metal substrate 410 printed on the inside of the non-metallic outer part 200 can induce multiple half-wavelength current modes when the antenna is working. These current modes are zero current at the open end of the thin metal strips on the four sides, and strong current at the "cross" intersection in the center of the structure.

[0086] In this embodiment, the FPC antenna is in the form of a PIFA antenna, with the radiator being a rectangular patch that is suspended in air. The relative permittivity of air is... The value is 1. The radiating patch of the PIFA antenna is 15mm long and 6mm wide. Refer to the PIFA antenna resonant frequency calculation formula:

[0087]

[0088] Where f is the resonant frequency of the antenna, L is the length of the antenna radiating plate 300, W is the width of the antenna radiating plate 300, and c is the speed of light. Under these dimensions, the calculated resonant frequency of the antenna is 3.57 GHz, therefore the antenna operates in the N78 frequency band.

[0089] In this embodiment, the cross-shaped metal strip at the center of the electromagnetic wave converter 400 has a length of 16mm in both the x and y directions. Because it is printed under a high-dielectric-constant glass back cover, the relative permittivity of the glass... The value is 7.2, referring to the antenna wavelength calculation formula:

[0090]

[0091] Based on the above formula, the wavelength in the N78 band is approximately 34mm. The length of the central cross-shaped metal strip in the x and y directions is 16mm, slightly shorter than half the wavelength of the N78 band where the antenna operates. This allows for better sensing of the current radiated by the FPC antenna in the N78 band. Furthermore, in this embodiment, the resonant frequency of the half-wavelength current mode of the bottom metal strip can be finely adjusted by controlling the length of the thin metal strip on the side of the electromagnetic wave converter 400, making it close to the antenna's operating frequency. This ensures that the metal strip can sense a strong half-wavelength mode current in the N78 band where the antenna operates. In this embodiment, the length of the thin metal strip on the side is 8mm. The first extension branch 413, the second extension branch 414, the third extension branch 415, and the fourth extension branch 416 are the aforementioned thin metal strip on the side.

[0092] Because the metal substrate 410 of the electromagnetic wave converter 400 is printed on a high dielectric constant material, its overall size can be reduced to [size missing]. It is relatively compact, with a lateral dimension similar to that of an FPC antenna suspended in air.

[0093] like Figure 9A and Figure 9B As shown, when the antenna is working, the induced current is relatively strong on the "cross-shaped" metal strip at the center of the electromagnetic wave converter 400. A metal pillar 420, extending Z-axis through the glass back cover, is designed on this part of the metal strip to effectively disperse part of the induced current, thereby generating a current component perpendicular to human tissue. In this embodiment, 10 sets of metal pillars 420 are arranged in both the x and y directions to disperse the induced current of the metal strip, wherein the size of a single metal pillar 420 is... The columns are arranged in pairs, with the central pairs of columns spaced 0.1mm apart, and the other adjacent pairs spaced 1.5mm apart. Figure 9A and Figure 9BAs shown, the current induced by the FPC antenna through the metal strip is partially dispersed onto the metal pillar 420. The current in the metal pillar 420 is distributed in the Z-direction. This portion of the current is perpendicular to the human tissue in the direction of the battery cover, and the main polarization direction of its radiated electric field is perpendicular to the normal direction of the human tissue. Therefore, the polarization conversion of the radiated electric field of the FPC antenna from tangential to normal is achieved, reducing the antenna SAR value. In this embodiment, for aesthetic reasons, the metal pillar 420 does not protrude from the battery cover area, and its length is designed to be 1mm, consistent with the thickness of the battery cover. The metal pillar 420 introduces current perpendicular to the direction away from the human tissue. The longer its length and the more groups set, the greater the proportion of the dispersed Z-direction current component, and the better the SAR reduction effect will be. In the design, its length should be no less than 1mm. However, the length and number of pillars will affect the resonant frequency of the metal strip and need to be adjusted together with the metal strip. When the length and number of pillars increase, the resonant frequency of the metal strip will decrease. In order to better sense the antenna current, the length of the metal strip needs to be shortened. In practical applications, the length and number of metal columns 420 can be adjusted according to factors such as antenna resonant frequency, SAR reduction requirements, space, and appearance.

[0094] In this embodiment, the metal substrate 410 at the bottom center of the electromagnetic wave converter 400 serves to induce the current of the FPC antenna as strongly as possible and then distribute it onto the column to achieve as much Z-axis current as possible, thereby radiating more electric field components perpendicular to human tissue. However, loading too many metal strips around the antenna can affect its radiation performance. Therefore, the metal substrate 410 is designed in a "cross" shape in this embodiment for the following two main reasons:

[0095] When the antenna is working, the current is distributed on the radiating patch of its main radiator, and the current is as follows: Figure 7 As shown, there are both x and y components; the coupling metal strip on the cover is designed in a cross shape. The two orthogonal metal strips in the x and y directions can respectively sense the current in the x and y directions of the antenna radiating plate 300. Compared with the branches of the coupling metal strip in a single direction, it can simultaneously couple the components in the X and Y directions, achieve more sufficient excitation, and enhance the induced current on the metal strip.

[0096] The metal strip is designed with two cross-shaped intersections in the x and y directions. The center intersection point is the current-strong point, and the four ends are current-weak points. For example... Figure 9A and Figure 9B As indicated by the arrow markings in the medium current distribution, it possesses multiple branches of half-wavelength current modes, such as... Figure 9A and Figure 9B The schematic diagrams 1-4 show that, in contrast to the independent half-wavelength metal strip branches, only the current mode of the half-wavelength dipole exists. Therefore, the "cross-shaped" metal strip design can be better excited by the FPC antenna, enhancing the induced current on the metal strip.

[0097] In this embodiment, by intersecting the two metal strips in the x and y directions to form a "cross shape," a better antenna current sensing effect is achieved compared to other schemes that use as few metal strips as possible.

[0098] Figure 10 and Figure 11 The simulation results of the electric field on the plane 5mm away from the battery cover are shown in two cases: one with a conventional battery cover and the other with the polarization-conversion battery cover in this embodiment, both operating in the N78 frequency band of the FPC antenna. The polarization-conversion battery cover is the non-metallic exterior part 200 with the aforementioned electromagnetic wave converter 400. The comparison shows that after loading the polarization-conversion battery cover, the peak tangential electric field on this plane decreases from 518V / m with the conventional battery cover to 358V / m, indicating a significant reduction in the peak tangential electric field; the peak normal electric field increases from 349V / m with the conventional battery cover to 489V / m. The electromagnetic wave converter 400 achieves partial conversion of the electric field polarization, reducing the intensity of the tangential electric field on the opposite side.

[0099] Two battery cover simulations with a 5mm back-facing Body-SAR, such as Figure 12 and Figure 13 As shown, the antenna simulation power was set to 0.2 W. The antenna efficiencies were similar under both battery covers, and the 10-g average SAR was observed. Compared with the conventional battery cover, the simulation results of the polarization-conversion battery cover in this embodiment showed that the 10-g average SAR peak value decreased from 2.6 W / kg to 1.77 W / kg, achieving a SAR reduction effect of 32% (1.6 dB).

[0100] Table 1: Figure 2A Comparison of the antenna specifications of the illustrated embodiment with those of a conventional battery cover antenna

[0101]

[0102] Figure 14 and Figure 15 This paper compares the antenna reflection coefficient and radiation efficiency under the battery cover scheme in this embodiment with those under a conventional battery cover scheme. Specific antenna specifications are summarized in Table 1. Compared to the conventional battery cover scheme, this embodiment shows minimal change in antenna radiation performance, with a resonant point shifted to a higher frequency of approximately 40MHz, an overall -6dB impedance bandwidth increase of 30MHz, and approximately the same in-band antenna efficiency. Therefore, this embodiment reduces the backscattered SAR value of the FPC antenna by 32% without degrading antenna radiation performance.

[0103] In this embodiment, the metal strip and metal pillar 420 located on the battery cover can sense the FPC antenna current and generate a Z-direction current, converting the electric field portion radiated by the FPC antenna in the tangential direction relative to the human body into a normal electric field, thereby reducing the overall back SAR value of the antenna without affecting the antenna radiation performance.

[0104] Figure 2A The illustrated embodiments have at least the following beneficial effects:

[0105] The proposed SAR reduction scheme integrates the SAR reduction structure into the battery cover of key equipment, without requiring additional internal design space, which can improve the internal integration of terminal equipment.

[0106] Without affecting the antenna radiation performance, the back SAR value of the FPC antenna on the motherboard bracket is reduced by 32%, which can significantly reduce the conduction drop caused by its high back SAR value, improve antenna performance and user's Internet experience.

[0107] Optionally, please see Figure 16 The first axis of symmetry of the first rectangular region enclosed by the edge of the electromagnetic wave converter 400 is aligned with the first side 310 of the antenna radiating plate 300, and the second axis of symmetry of the first rectangular region is aligned with the axis of symmetry of the antenna radiating plate 300 perpendicular to the first side 310. The feed point 311 of the antenna radiating plate 300 is located on the first side 310 of the antenna radiating plate 300.

[0108] In some embodiments of this application, the middle part of the first metal strip 411 coincides with the middle part of the second metal strip 412, the first metal strip 411 is perpendicular to the second metal strip 412, and the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is provided with four metal columns 420 arranged in a rectangular array; the first extension branch 413 and the second extension branch 414 are respectively parallel to the second metal strip 412, and the third extension branch 415 and the fourth extension branch 416 are respectively parallel to the first metal strip 411. The first extension branch 413 and the second extension branch 414 are parallel to the second metal strip 412, respectively; the third extension branch 415 and the fourth extension branch 416 are parallel to the first metal strip 411, respectively; the first axis of symmetry of the first rectangular region enclosed by the edge of the electromagnetic wave converter 400 is aligned with the first side 310 of the antenna radiating plate 300; the second axis of symmetry of the first rectangular region is aligned with the axis of symmetry of the antenna radiating plate 300 perpendicular to the first side 310; and the feed point 311 of the antenna radiating plate 300 is located on the first side 310 of the antenna radiating plate 300.

[0109] Please see Figure 16 ,and Figure 2A Compared to the embodiments shown, Figure 16 The embodiment shown converts electromagnetic waves from... Figure 2A The centered position shown is moved in the -y direction, so that the first metal strip 411 of the bottom-printed "cross-shaped" metal substrate 410 is aligned with the feed side of the FPC antenna radiating plate 300. The current distribution during FPC antenna operation is as follows... Figure 7 As shown, it has a strong current distribution on the feeding side of the antenna radiating plate 300. Based on this, in this embodiment, by aligning the first metal strip 411 of the electromagnetic wave converter 400 with the strong current side of the antenna radiating plate 300, the coupling effect between the two can be strengthened, the coupling current intensity of the coupling strip from the antenna patch in the antenna operating frequency band can be increased, thereby strengthening the current intensity of the metal column 420 and improving the polarization conversion effect of the electric field.

[0110] In this embodiment, by aligning the first axis of symmetry of the first rectangular region enclosed by the edge of the electromagnetic wave converter 400 with the first side 310 of the antenna radiating plate 300, and aligning the second axis of symmetry of the first rectangular region with the axis of symmetry of the antenna radiating plate 300 perpendicular to the first side 310, and with the feed point 311 of the antenna radiating plate 300 located on the first side 310 of the antenna radiating plate 300, the coupling effect between the electromagnetic wave converter 400 and the antenna radiating plate 300 can be enhanced. This can increase the coupling current intensity of the coupling strip from the antenna patch within the antenna operating frequency band, thereby enhancing the current intensity of the metal column 420 and improving the polarization conversion effect of the electric field.

[0111] Optionally, the extension direction of the first axis of symmetry is the same as the extension direction of the first metal strip 411, and the orthographic projection of the feed point 311 in the first metal strip 411 is located between the overlapping region 417 and the second extension branch 414.

[0112] In the first metal strip 411, a group of first pillars 430 is provided at every second distance from the overlapping area 417 to the first end of the first metal strip 411; and in the first metal strip 411, a group of first pillars 430 is provided at every third distance from the overlapping area 417 to the second end of the first metal strip 411, wherein the second distance is greater than the third distance, and the overlapping area 417 is the overlapping area of ​​the first metal strip 411 and the second metal strip 412;

[0113] In the second metal strip 412, a group of second columns 440 is provided at each third distance from the overlapping area 417 to the end of the second metal strip 412.

[0114] In some embodiments of this application, the middle part of the first metal strip 411 coincides with the middle part of the second metal strip 412, the first metal strip 411 is perpendicular to the second metal strip 412, and the overlapping area 417 of the first metal strip 411 and the second metal strip 412 is provided with four metal columns 420 arranged in a rectangular array; the first extension branch 413 and the second extension branch 414 are respectively parallel to the second metal strip 412, and the third extension branch 415 and the fourth extension branch 416 are respectively parallel to the first metal strip 411. The first extension branch 413 and the second extension branch 414 are parallel to the second metal strip 412, respectively; the third extension branch 415 and the fourth extension branch 416 are parallel to the first metal strip 411, respectively; the first axis of symmetry of the first rectangular region enclosed by the edge of the electromagnetic wave converter 400 is aligned with the first side 310 of the antenna radiating plate 300; the second axis of symmetry of the first rectangular region is aligned with the axis of symmetry of the antenna radiating plate 300 perpendicular to the first side 310; and the feed point 311 of the antenna radiating plate 300 is located on the first side 310 of the antenna radiating plate 300. The extension direction of the first axis of symmetry is the same as the extension direction of the first metal strip 411. The orthographic projection of the feed point 311 in the first metal strip 411 is located between the overlapping region 417 and the second extension branch 414. In the first metal strip 411, a group of first pillars 430 is provided at every second distance from the overlapping region 417 to the first end of the first metal strip 411. In the first metal strip 411, a group of first pillars 430 is provided at every third distance from the overlapping region 417 to the second end of the first metal strip 411, wherein the second distance is greater than the third distance. In the second metal strip 412, a group of second pillars 440 is provided at every third distance from the overlapping region 417 to the end of the second metal strip 412.

[0115] The values ​​of the second distance and the third distance can be set as needed. For example, in some embodiments of this application, the second distance is 2mm and the third distance is 1mm.

[0116] Figure 16 The illustrated embodiments and Figure 2A The main difference in the illustrated embodiment lies in the optimized relative positions of the electromagnetic wave converter 400 and the antenna radiating plate 300, as well as the density of the metal pillars 420. The electromagnetic wave converter 400... Figure 2AIn the illustrated embodiment, the entire structure is moved in the -y direction, aligning the horizontal strip of the bottom-printed "cross-shaped" coupling metal strip in the x-direction with the side of the FPC antenna radiating plate 300 that is being fed. The density of the metal pillars 420 is also adjusted, with the spacing between each group of pillars closer to the antenna feed point 311 increased to 1 mm, while the spacing between the metal pillars 420 further away from the feed point is decreased to 2 mm. Figure 16 The area highlighted by the dashed line is the 420 encrypted area of ​​the metal pillar.

[0117] The current distribution during FPC antenna operation is as follows: Figure 7 As shown, it has a strong current distribution on the feeding side of the antenna radiating plate 300. In this embodiment, the first metal strip 411 is aligned with the strong current side of the antenna radiating plate 300 to enhance the coupling effect between the two. This can increase the coupling current intensity of the coupling strip from the antenna patch in the antenna operating frequency band, thereby strengthening the current intensity of the metal column 420 and improving the polarization conversion effect of the electric field.

[0118] When the FPC antenna is working, the current distribution of the coupling metal strip of the electromagnetic wave converter 400 is as follows: Figure 9B As shown. Because the current is stronger near the feed point 311 in the antenna radiating plate 300, the induced current in the electromagnetic wave converter 400 coupled to the metal strip is significantly stronger near the feed point than far from it. In this embodiment, the number of metal pillars 420 is increased at locations with stronger induced current, while the number of pillars in areas with weaker induced current is reduced. This improves the overall dispersion efficiency of the metal pillars 420 on the coupled metal strip current, and increases the proportion of the normal current perpendicular to the human tissue. Compared to... Figure 2A In the embodiment shown, the metal columns 420 are evenly distributed at equal intervals on the coupling metal strip. Figure 16 The illustrated embodiment can further improve the polarization conversion effect of the electric field and reduce the SAR value in the back cover direction.

[0119] Table 2: Figure 2A The illustrated embodiments and Figure 16 Performance comparison of the illustrated embodiments

[0120]

[0121] Figure 2A The illustrated embodiments and Figure 16 The reflection coefficient and efficiency of the antenna simulation in the illustrated embodiment are compared as follows: Figure 17 and Figure 18 As shown, Figure 19 The simulation results of the 5 mm back-facing Body-SAR values ​​in this embodiment were presented in Table 2. Figure 2A The illustrated embodiments and Figure 16 Performance comparison of the illustrated embodiments. Figure 16The illustrated embodiment adjusts the position of the electromagnetic wave converter 400 integrated in the back cover relative to the antenna, and changes the density of the metal pillars 420 according to the current distribution of the coupling metal strip, causing the antenna resonant point to shift to a higher frequency. Because the coupling metal strip is closer to the antenna, the antenna clearance is affected, resulting in a 50MHz reduction in bandwidth. Figure 16 The antenna in the illustrated embodiment has a -6dB impedance of 3.3~3.78GHz and can still operate in the N78 band; the efficiency within the antenna's operating frequency band is approximately unaffected, and the radiation efficiency and overall efficiency are similar to... Figure 2A The illustrated embodiments showed reductions of -0.01 and -0.05 dB, respectively. Figure 16 The antenna simulation in the illustrated embodiment is a 5 mm back-facing Body-SAR. Figure 19 As shown, its 10-g average SAR peak value is 1.32 W / kg, compared to... Figure 2A In the illustrated embodiment, the antenna SAR peak value of 1.77 W / kg represents a further 25.4% reduction. Among these, Figures 17 to 18 The solid line in the middle is Figure 16 Simulation results of the illustrated embodiment, Figures 17 to 18 The dotted line in the middle is Figure 2A Simulation results of the illustrated embodiment.

[0122] In this embodiment, by optimizing the relative position of the electromagnetic wave converter 400 and the antenna, and adjusting the density of the metal columns 420 according to the induced current distribution, the polarization conversion effect of the polarization conversion battery cover on the antenna electric field is further enhanced, and the back-side SAR reduction effect is improved by 25.4%. This can further improve the overall SAR reduction TRP of the antenna, maintain good communication competitiveness, and improve the user experience.

[0123] Optionally, the non-metallic exterior component 200 is a non-metallic back cover, and the electronic device further includes a ground plane 100. The ground plane 100, the antenna radiating plate 300 and the non-metallic exterior component 200 are arranged in sequence, and a second gap 500 is provided between the ground plane 100 and the antenna radiating plate 300.

[0124] In related technologies, the number of antennas required for 5G terminal equipment is increasing. The industry usually deploys 1 to 2 FPC antennas on the motherboard bracket for 5G N78 / N79 frequency band radiation. The main radiation direction of the FPC antenna is the direction of the battery back cover, which can easily cause the terminal equipment to have excessively high back SAR.

[0125] In this embodiment, since the direction of maximum radiation intensity of the antenna radiator is towards the human tissue, and the radiated electric field is planned to be parallel to the human tissue, a strong tangential electric field will be generated in the human tissue. Therefore, by setting an electromagnetic wave converter opposite to the antenna radiator in the non-metallic back cover, the electromagnetic wave converter includes: a metal substrate opposite to the antenna radiator, and a metal pillar protruding from the side of the metal substrate opposite to the antenna radiator. The metal substrate is coupled to the antenna radiator, so the energy coupled to the substrate can be dispersed to the metal pillar. The direction of the current in the metal pillar is perpendicular to the human tissue, and the main polarization direction of its radiated electric field is normal to the human tissue. This can convert part of the radiated electric field of the metal radiator from tangential to normal, thereby reducing the tangential electric field strength generated by the antenna radiator in the human tissue, which is beneficial to reducing the antenna SAR value, that is, reducing the SAR value of the electronic device on the back.

[0126] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. An electronic device, comprising: It includes a non-metallic exterior component, an antenna radiating plate, and an electromagnetic wave conversion component. The antenna radiating plate is disposed opposite to the non-metallic exterior component, and there is a first gap between the antenna radiating plate and the non-metallic exterior component. The electromagnetic wave converter is embedded in the non-metallic exterior component. The electromagnetic wave converter includes: a metal substrate disposed opposite to the antenna radiating plate, and a metal post protruding from the side of the metal substrate opposite to the antenna radiating plate; wherein the metal substrate is coupled to the antenna radiating plate.

2. The electronic device of claim 1, wherein, The metal substrate includes a first metal strip and a second metal strip arranged in a cross pattern. The first metal strip has a plurality of metal pillars on the side facing away from the antenna radiating sheet, and the second metal strip has a plurality of metal pillars on the side facing away from the antenna radiating sheet.

3. The electronic device of claim 2, wherein, The length of the first metal strip is matched to half the operating wavelength of the antenna radiating plate, and the length of the second metal strip is matched to half the operating wavelength of the antenna radiating plate.

4. The electronic device of claim 2 or 3, wherein, The multiple metal pillars disposed on the side of the first metal strip opposite to the antenna radiating sheet form multiple first pillar groups. The multiple first pillar groups are arranged sequentially at intervals along the length direction of the first metal strip. Each first pillar group includes two metal pillars, and the two metal pillars in the first pillar group are arranged at intervals along the width direction of the first metal strip. The multiple metal pillars disposed on the side of the second metal strip opposite to the antenna radiating sheet form multiple second pillar groups. The multiple second pillar groups are arranged sequentially at intervals along the length direction of the second metal strip. Each second pillar group includes two metal pillars, and the two metal pillars in the second pillar group are arranged at intervals along the width direction of the second metal strip.

5. The electronic device of claim 4, wherein, The metal substrate further includes a first extension branch, a second extension branch, a third extension branch, and a fourth extension branch. The first end of the first metal strip is connected to the middle of the first extension branch, the second end of the first metal strip is connected to the middle of the second extension branch, the first end of the second metal strip is connected to the middle of the third extension branch, and the second end of the second metal strip is connected to the middle of the fourth extension branch.

6. The electronic device according to claim 5, characterized in that, The first metal strip is perpendicular to the second metal strip, and the middle part of the first metal strip coincides with the middle part of the second metal strip.

7. The electronic device of claim 5, wherein, The overlapping area of ​​the first metal strip and the second metal strip is provided with four metal columns arranged in a rectangular array.

8. The electronic device of claim 5, wherein, The first and second extension branches are parallel to the second metal strip, respectively, and the third and fourth extension branches are parallel to the first metal strip, respectively.

9. The electronic device of claim 8, wherein, The center of the first rectangular region enclosed by the edge of the electromagnetic wave converter is aligned with the center of the second rectangular region enclosed by the edge of the antenna radiating plate, and the two axes of symmetry of the first rectangular region are aligned with the two axes of symmetry of the second rectangular region. The feed point of the antenna radiating plate is located on the first side of the antenna radiating plate.

10. The electronic device of claim 9, wherein, In the first metal strip, a group of first columns is provided at a first distance from the overlapping area to the end of the first metal strip, wherein the overlapping area is the overlapping area of ​​the first metal strip and the second metal strip; In the second metal strip, a group of second columns is provided at intervals of the first distance from the overlapping area to the end of the second metal strip.

11. The electronic device of claim 8, wherein, The first axis of symmetry of the first rectangular region enclosed by the edge of the electromagnetic wave converter is aligned with the first side of the antenna radiating plate, and the second axis of symmetry of the first rectangular region is aligned with the axis of symmetry of the antenna radiating plate perpendicular to the first side. The feed point of the antenna radiating plate is located on the first side of the antenna radiating plate.

12. The electronic device of claim 11, wherein, The extension direction of the first axis of symmetry is the same as the extension direction of the first metal strip. The orthographic projection of the feed point in the first metal strip is located between the overlapping region and the second extension branch. The overlapping region is the overlapping region of the first metal strip and the second metal strip. In the first metal strip, a group of first pillars is provided at every second distance from the overlapping area to the first end of the first metal strip; and in the first metal strip, a group of first pillars is provided at every third distance from the overlapping area to the second end of the first metal strip, wherein the second distance is greater than the third distance; In the second metal strip, a group of second columns is provided every third distance from the overlapping area to the end of the second metal strip.

13. The electronic device according to any one of claims 1 to 3, wherein The non-metallic exterior component is a non-metallic back cover. The electronic device also includes a ground plane. The ground plane, the antenna radiating plate, and the non-metallic exterior component are arranged in sequence, and there is a second gap between the ground plane and the antenna radiating plate.

Images