Patent ID: 12212052

DESCRIPTION OF EMBODIMENTS

The following clearly describes the technical solutions in embodiments of this application with reference to the accompanying drawings in the embodiments of this application.

This application provides an electronic device, and the electronic device includes an antenna for communicating with the outside. When the electronic device is in free space (FS) or a beside head and hand mode (including a beside head and hand left side mode and a beside head and hand right side mode), the antenna can achieve a relatively good working effect, to avoid impact on signal transmission of the antenna when the electronic device is held by a hand, and in particular, to avoid impact on transmission of a low-frequency (low band, LB) signal of the antenna when the electronic device is held by a hand. A frequency of the low-frequency signal of the antenna usually ranges from 699 MHz to 960 MHz. The electronic device may be a portable electronic apparatus or another appropriate electronic apparatus. For example, the electronic device may be a notebook computer, a tablet computer, a relatively small device such as a mobile phone, a watch, an accessory device, or another wearable or micro device, a cellular phone, or a media player.

FIG.1is a schematic diagram of a structure of an electronic device100according to an embodiment of this application. In this embodiment, the electronic device100is a mobile phone. The electronic device100includes a frame10and a display20. The frame10is disposed around the display20. The frame10includes two first edges11that are disposed opposite to each other and two second edges12that intersect with the two first edges11. The two first edges11and the two second edges12are head-to-tail connected to form the frame10in a square shape. In this embodiment, the electronic device100is of a square tabular structure, that is, the frame10is in the square shape. In some embodiments, the frame10includes a chamfer, to present a more aesthetically pleasing effect for the frame10. An extension direction of the second edge12is a horizontal direction (an X direction shown in the figure), and an extension direction of the first edge11is a vertical direction (a Y direction shown in the figure). In this embodiment, a length of the first edge11is greater than a length of the second edge12. It may be understood that in some embodiments, the extension direction of the first edge11and the extension direction of the second edge12may be changed, and the length of the first edge11and the length of the second edge12may also be changed. This is not specifically limited herein. For example, in some embodiments, the extension direction of the first edge11may be the horizontal direction, and the extension direction of the second edge12may be the vertical direction. The length of the first edge11may be less than the length of the second edge12. In this embodiment, the frame10may be made of a conductive material such as metal, or may be made of a non-conductive material such as plastic or resin.

The display20is configured to display an image, a video, and the like. The display20may be a flexible display or a rigid display. For example, the display20may be an organic light-emitting diode (OLED) display, an active-matrix organic light-emitting diode (AMOLED) display, a mini organic light-emitting diode display, a micro light-emitting diode display, a micro organic light-emitting diode display, a quantum dot light-emitting diode (QLED) display, or a liquid crystal display (LCD).

Referring toFIG.2, the electronic device100further includes an antenna40and a radio frequency front end50. The antenna40includes an antenna body41. The antenna body41is configured to radiate a radio frequency signal to the outside or receive a radio frequency signal from the outside, so that the electronic device100can communicate with the outside by using the antenna body41. The radio frequency front end50connects to the antenna body41, and is configured to feed a radio frequency signal into the antenna body41or receive an external radio frequency signal received by the antenna body41. In some embodiments, the radio frequency front end50includes a transmit channel and a receive channel. The transmit channel includes components such as a power amplifier and a filter. A signal is transmitted to the antenna body41after processing such as power amplification and filtering is performed by using components such as the power amplifier and the filter, and is transmitted to the outside by the antenna body41. The receive channel includes components such as a low noise amplifier and a filter. An external signal received by the antenna body41is transmitted to a radio frequency chip after processing such as low noise amplification and filtering is performed by using components such as the low noise amplifier and the filter, to implement communication between the electronic device100and the outside by using the radio frequency front end50and the antenna40.

The antenna body41is of an L-shaped structure, and includes a first section411and a second section412that intersects with the first section411. An end that is of the first section411and that is far away from the second section412is a first end A, and an end that is of the second section412and that is far away from the first section411is a second end B. It should be emphasized that in some other embodiments of this application, the first end A and the second end B may be interchanged. In other words, in some embodiments, the end that is of the second section412and that is far away from the first section411is the first end A, and the end that is of the first section411and that is far away from the second section412is the second end B.

The antenna body41includes a feed point413and a grounding point414that are disposed with an interval. The grounding point414may be located between the feed point413and the first end A, or may be located between the feed point413and the second end B. The feed point413is configured to electrically connect to the radio frequency front end50, so that a signal generated by the radio frequency front end50can be transmitted to the antenna body41through the feed point413, and transmitted to the outside through the antenna body41. Alternatively, the external signal received by the antenna body41is transmitted to the radio frequency front end50through the feed point413. It should be noted that the feed point413in this application is not an actual point, and a position at which the radio frequency front end50connects to the antenna body41is the feed point413in this application.

The grounding point414is grounded, and an electrical length of the antenna body41can be adjusted by adjusting a position of the grounding point414. A resonance frequency of the antenna body41can be changed if the electrical length is changed. In some embodiments, the grounding point414is grounded by using a grounding member such as a grounding pin or a grounding wire. One end of the grounding member connects to the grounding point414of the antenna body41, and the other end is grounded, so that the grounding point414is grounded. It should be noted that the grounding point414in this application is not an actual point, and a position at which the grounding member such as the grounding pin or the grounding wire connects to the antenna body41is the grounding point414.

It should be noted that the electrical length of the antenna body41in this application may be measured in a plurality of manners. For example, in some embodiments, the electrical length of the antenna body41may be measured by using a passive test method. Specifically, the antenna is manufactured into a jig, each of the first end A and the second end B of the antenna body41is sealed with a copper sheet, and changes of return loss diagrams of the antenna measured at different moments are observed, to determine an electrical length, of the antenna body41, between the first end A and the second end B and an electrical length between the feed point413and the first end A or the second end B.

FIG.3is a schematic diagram of an internal structure of the electronic device100shown inFIG.1. The electronic device100further includes a middle frame30. The display20is stacked with the middle frame30, and the frame10is disposed around the middle frame30. In this embodiment, the middle frame30is made of a conductive material (for example, a metal material) such as metal, and the middle frame30is grounded. When the frame10is made of a conductive material, at least a part of the frame10may electrically connect to the middle frame30, to ground the frame10by using the middle frame30. It may be understood that in some other embodiments of this application, the electronic device100may not include the middle frame30, and the frame10may connect to another grounding position by using a grounding member, to implement grounding.

In some embodiments of this application, the frame10is made of a metal material, and some sections of the frame10can be used as the antenna body41, to reduce space occupied by the antenna40. In the embodiment shown inFIG.3, a first slot111is disposed on one first edge11, a second slot121is disposed on a second edge12, and the frame10between the first slot111and the second slot121forms the antenna body41in this embodiment. A part that is of the first edge11and that is between the first slot111and the second edge12is the first section411of the antenna body41, and a part that is of the second edge12and that is between the second slot121and the first edge11is the second section412of the antenna body41. The antenna body41is electrically isolated from a part other than the antenna body41on the frame10by using the first slot111and the second slot121. In addition, there is a gap42between the antenna body41and the middle frame30, to ensure a good clearance environment for the antenna body41, so that the antenna40has a good signal transmission function. In some embodiments, the part other than the antenna body41on the frame10may connect to the middle frame30, and may be integrally formed with the middle frame30. It may be understood that when the part other than the antenna body41on the frame10is used as an antenna body of another antenna (for example, a Wi-Fi antenna or a GPS antenna) of the electronic device, there is also a gap42between the part other than the antenna body on the frame10and the middle frame30, to ensure a good clearance environment for the antenna.

The antenna body41includes the first end A and the second end B. In this embodiment, an end face of the first end A faces the first slot111, and an end face of the second end B faces the second slot121. In this case, the first end A is located in the vertical direction of the electronic device100, and the second end B is located in the horizontal direction of the electronic device100. It may be understood that when the extension direction of the first edge11of the antenna body41is the horizontal direction, and the extension direction of the second edge12is the vertical direction, the first end A whose end face faces the first slot111is located in the horizontal direction, and the second end B whose end face faces the second slot121is disposed in the vertical direction.

In this application, a distance between the first slot111and the second edge12and a distance between the second slot121and the first edge11are not specifically limited. In some embodiments, the distance between the first slot111and the second edge12or the distance between the second slot121and the first edge11is greater than 90 mm, to avoid, to some extent, a case in which the first slot111or the second slot121is held when the electronic device is held by a hand. Therefore, the antenna40can still have relatively good radiation performance in a handheld state.

In some embodiments, the length of the first edge11is greater than the length of the second edge12, and the distance between the first slot111and the second edge12is greater than the distance between the second slot121and the first edge, that is, a length of the first section411is greater than a length of the second section412. The second section412that is of a relatively short length and that is of the antenna body41is located on the second edge12that is of a relatively short length and that is of the frame10, and the first section411that is of a relatively long length and that is of the antenna body41is located on the first edge11that is of a relatively long length and that is of the frame10, and therefore more L-shaped antennas can be further arranged on the frame10, to implement a relatively proper antenna arrangement on the frame10.

In some embodiments, the first slot111and the second slot121may be filled with a dielectric material, to further enhance an electrical isolation effect between the antenna body41and a part other than the antenna body41on the frame10.

Referring toFIG.4, in some embodiments, when the frame10of the electronic device100is made of a non-conductive material, the frame10cannot be used as the antenna body41. A difference between this embodiment and the embodiment shown inFIG.3lies in that the antenna body41is located in the electronic device100. In this embodiment, the antenna body41is disposed abut to the frame10, to minimize a size occupied by the antenna40and enable the antenna40to be closer to the outside of the electronic device100, so as to implement a better signal transmission effect. It should be noted that in this application, that the antenna body41is disposed abut to the frame10means that the antenna body41may be disposed in close contact with the frame10, or may be disposed close to the frame10, that is, there can be a small gap between the antenna body41and the frame10. In this embodiment, the first slot111and the second slot121do not need to be disposed on the frame10, and a radio frequency signal output or received by the antenna body41can be transmitted through the frame10, to prevent the frame10from restricting signal transmission of the antenna40. The antenna40may be in an antenna form of a flexible printed circuit (FPC), a laser direct structuring (LDS) antenna, a microstrip disk antenna (MDA), or the like.

In the embodiments shown inFIG.3andFIG.4, the antenna body41connects to the middle frame30by using a grounding pin44. The middle frame30is grounded, and therefore the grounding point414is grounded by using the grounding pin44. Specifically, one end of the grounding pin44connects to the antenna body41, and the other end connects to the middle frame30. A position at which the grounding pin44connects to the antenna body41is the grounding point414of the antenna body41. In the embodiments shown inFIG.3andFIG.4, the antenna body41connects to the radio frequency front end50by using a feed pin43. Specifically, one end of the feed pin43connects to the antenna body41, and the other end connects to the radio frequency front end50. A position at which the feed pin43connects to the antenna body41is the feed point413of the antenna body41. It may be understood that in some other embodiments of this application, the antenna body41may connect to the middle frame30by using another structure such as a connection lead, or may connect to the radio frequency front end50by using another structure such as a connection lead. This is not specifically limited herein.

In some embodiments, an electrical length between the feed point413and the first end A is greater than an electrical length between the feed point413and the second end B, and the electrical length between the feed point413and the first end A is approximately a first wavelength in a quarter wavelength mode, so that resonance of the first wavelength in the quarter wavelength mode can be generated in a section between the feed point413and the first end A of the antenna body41. When the antenna40works, mode excitation in a direction perpendicular to the first end A can be generated through excitation based on the resonance that is of the first wavelength in the quarter wavelength mode and that is generated in the section between the feed point413and the first end A of the antenna body41. The first wavelength is an operating wavelength of the resonance of the first wavelength in the quarter wavelength mode. For example, in the embodiment shown inFIG.3, when the extension direction of the first edge11is the vertical direction (the Y direction in the figure), the end face of the first end A faces the first slot111on the first edge11, that is, the first end A is located in the vertical direction. In this case, horizontal mode excitation is generated through excitation based on the resonance that is of the first wavelength in the quarter wavelength mode and that is generated between the feed point413and the first end A of the antenna body41. In some embodiments, when the extension direction of the first edge11is the horizontal direction (the X direction in the figure), the end face of the first end A faces the first slot111on the first edge11, that is, the first end A is located in the horizontal direction. In this case, vertical mode excitation is generated through excitation based on the resonance that is of the first wavelength in the quarter wavelength mode and that is generated in the section between the feed point413and the first end A.

In this embodiment of this application, the electrical length between the feed point413and the first end A is greater than the electrical length between the feed point413and the second end B, and therefore it is set that a section (namely, the section between the feed point413and the first end A) of a relatively long electrical length is of approximately the first wavelength in the quarter wavelength mode, to generate the resonance of the first wavelength in the quarter wavelength mode, so that the resonance of the first wavelength in the quarter wavelength mode can have a relatively large radiation aperture. Therefore, the antenna40has relatively good radiation performance.

In this embodiment of this application, the feed point413may be disposed at any position of the antenna body41. Specifically, a position of the feed point413or a position of the first end A may be correspondingly changed based on a specific actual situation of the electronic device100, to control a direction in which mode excitation is to be generated. For example, when the electronic device100shown inFIG.3is designed with a narrow chin structure, there is relatively small clearance space on a bottom edge (an edge that extends in a direction of an X axis inFIG.3) of the electronic device100. When there is a relatively good clearance environment on a side edge (an edge that extends in the Y direction inFIG.3) of the electronic device100, the first edge11of the frame10may be disposed at a position on the side edge of the electronic device, so that the extension direction of the first edge11is the Y direction, and the first end A is located in the vertical direction, to obtain horizontal mode excitation. When there is a poor clearance environment on the side edge of the electronic device100, and there is a relatively good clearance environment on the bottom edge, the first edge11of the frame10may be disposed at a position on the bottom edge of the electronic device, so that the extension direction of the first edge11is the X direction, and the first end A is located in the horizontal direction, to obtain vertical mode excitation. In this embodiment, the extension direction of the first edge11is the Y direction, and the first end A is located in the vertical direction. The feed point413is located in the first section411of the antenna body41. In this embodiment, the length of the first section411of the antenna body41is greater than the length of the second section412, and therefore when the feed point413is disposed in the first section411, a physical length between the feed point413and the first end A is usually greater than a physical length between the feed point413and the second end B. Therefore, a case in which the electrical length between the feed point413and the first end A is greater than the electrical length between the feed point413and the second end B and the resonance of the first wavelength in the quarter wavelength mode can be generated between the feed point413and the first end A can be implemented by connecting only a tuning element with a relatively small specification or without connecting a tuning element between the feed point413and the first end A. In this way, manufacturing costs can be reduced.

In some embodiments of this application, the electrical length between the first end A and the second end B is approximately a second wavelength in a half wavelength mode, and the antenna body41can generate resonance of the second wavelength in the half wavelength mode between the first end A and the second end B. The second wavelength is a wavelength of the resonance that is of the second wavelength in the half wavelength mode and that is formed between the first end A and the second end B. In some embodiments, the first wavelength and the second wavelength are operating wavelengths of signals whose radiation frequencies fall within a same frequency band (for example, B28, B5, or B8) in an LTE standard. The antenna body41is L-shaped, and therefore mode excitation in a direction perpendicular to the first section411and mode excitation in a direction perpendicular to the second section412can be generated, that is, horizontal mode excitation and vertical mode excitation can be generated, which can assist in enhancing the mode excitation generated based on the resonance of the first wavelength in the quarter wavelength mode, so that horizontal mode excitation and vertical mode excitation of the antenna40can be relatively strong, that is, both the horizontal mode excitation and the vertical mode excitation of the antenna can be relatively balanced. Therefore, the antenna40still has relatively good antenna radiation performance in the handheld state. In other words, in this application, the antenna body41can generate both the resonance of the first wavelength in the quarter wavelength mode and the resonance of the second wavelength in the half wavelength mode, and the mode excitation generated based on the resonance of the first wavelength in the quarter wavelength mode can be enhanced by using the resonance of the second wavelength in the half wavelength mode, so that the horizontal mode excitation and the vertical mode excitation of the antenna40are relatively balanced. Therefore, the antenna40can have relatively good radiation performance regardless of whether the electronic device100is in free space (FS) or in the handheld state. For example, in the embodiment inFIG.3, horizontal mode excitation is generated based on the resonance of the first wavelength in the quarter wavelength mode, and horizontal mode excitation and vertical mode excitation are generated based on the resonance of the second wavelength in the half wavelength mode, so that when the electronic device100is in the free space, both the horizontal mode excitation and the vertical mode excitation are relatively strong. Therefore, the antenna40has relatively good radiation performance. When the electronic device100is held by a hand and the electronic device100is in a portrait mode, holding of the first edge11of the electronic device100partially affects a magnitude of mode excitation of the electronic device100in the horizontal direction, but does not affect intensity of vertical mode excitation. Therefore, the antenna40still has good radiation performance. When the electronic device100is held by a hand and the electronic device100is in a landscape mode, holding of the second edge12of the electronic device100partially affects a magnitude of mode excitation of the electronic device100in the vertical direction, but does not affect intensity of horizontal mode excitation. Therefore, the antenna40still has good radiation performance.

In this application, when the antenna40works, the resonance of the first wavelength in the quarter wavelength mode and the resonance of the second wavelength in the half wavelength mode are generated. In some embodiments, the first wavelength is greater than the second wavelength, that is, a frequency of the resonance of the first wavelength in the quarter wavelength mode is less than a frequency of the resonance of the second wavelength in the half wavelength mode, to avoid generating an efficiency pit at a same operating frequency band (for example, a frequency band B28, B5, or B8), so that the antenna40can have good radiation performance at the operating frequency band.

In some embodiments, a difference between the frequency of the resonance generated between the feed point and the first end and the frequency of the resonance generated between the first end and the second end ranges from 50 MHz to 200 MHz, to implement better compatibility between the resonance of the first wavelength in the quarter wavelength mode and the resonance of the second wavelength in the half wavelength mode. Therefore, the antenna can have good radiation performance both in the free space and in the handheld state. In some embodiments, the difference between the frequency of the resonance of the first wavelength in the quarter wavelength mode and the frequency of the resonance of the second wavelength in the half wavelength mode may range from 50 MHz to 150 MHz.

Refer toFIG.5toFIG.8.FIG.6is a diagram of curves of a return loss coefficient (S11) of the antenna40of the electronic device100shown inFIG.3in different statuses (including the free space, a beside head and hand left side mode, and a beside head and hand right side mode). In the embodiment shown inFIG.3, the first end A is located on the first edge11of the frame10, and the first edge11is located in the vertical direction. InFIG.6, a horizontal coordinate is a frequency (unit: GHz), and a vertical coordinate is the return loss coefficient (unit: dB). A curve a represents a curve diagram of the return loss coefficient of the antenna40that exists when the electronic device100is in the free space. Curves b and c are curve diagrams of the return loss coefficient of the antenna40that exists when the electronic device100is held by a hand and the electronic device100is held in the portrait mode (a handheld state shown inFIG.5). The curve b represents a curve diagram of the return loss coefficient of the antenna40that exists when the electronic device100is in the beside head and hand left side mode (namely, a mode in which the electronic device100is held by a left hand and is close to a left side of the face). The curve c represents a curve diagram of the return loss coefficient of the antenna40that exists when the electronic device100is in the beside head and hand right side mode (namely, a mode in which the electronic device100is held by a right hand and is close to a right side of the face).FIG.7is a simulation diagram of a current and radiation direction existing when the antenna40of the electronic device100shown inFIG.3is in the free space.FIG.8is a diagram of radiation efficiency of the antenna40of an example structure of the electronic device100shown inFIG.3. InFIG.8, a horizontal coordinate is a frequency (unit: GHz), and a vertical coordinate is the radiation efficiency (unit: dB). A curve a represents a curve diagram of radiation efficiency of the antenna40that exists when the electronic device100is in the free space. A curve b represents a curve diagram of radiation efficiency of the antenna40that exists when the electronic device100is in the beside head and hand left side mode (namely, a mode in which the electronic device100is held by the left hand and is close to the left side of the face). A curve c represents a curve diagram of radiation efficiency of the antenna40that exists when the electronic device100is in the beside head and hand right side mode (namely, a mode in which the electronic device100is held by the right hand and is close to the right side of the face).

It may be easily learned fromFIG.6andFIG.7that the antenna40has two antenna modes in the free space, and therefore the antenna40has relatively high bandwidth. In addition, directivity patterns of the two antenna modes are complementary in specific space, so that the antenna40can have relatively good radiation efficiency in each direction, and a case in which the antenna40encounters a death grip when the electronic device100is held by a hand is avoided. In some embodiments, a directivity pattern obtained after complementation is oblique, and therefore there is no problem of death grip. In addition, it may be further learned fromFIG.6andFIG.8that in both the beside head and hand left side mode and the beside head and hand right side mode, radiation performance of the antenna40is slightly reduced, but the antenna40does not encounter a death grip. It may be learned fromFIG.8that there is a reduction of approximately 5 dB in the radiation efficiency of the antenna40when the radiation efficiency in the beside head and hand mode (including the beside head and hand left side mode or the beside head and hand right side mode) is compared with that in the free space, but the antenna40still has relatively good radiation efficiency.

In some embodiments, when the first end A of the antenna40is located on the second edge12of the frame10, the antenna40can still have relatively good radiation performance in the free space and the beside head and hand mode. Refer toFIG.9andFIG.10.FIG.9is another diagram of a curve of a return loss coefficient (S11) of the antenna40of an example structure of the electronic device100according to this application. The first end A of the antenna40represented inFIG.9is located on the second edge12of the frame10of the electronic device100. InFIG.9, a horizontal coordinate is a frequency (unit: GHz), and a vertical coordinate is the return loss coefficient (unit: dB). A curve a represents a curve diagram of the return loss coefficient of the antenna40that exists when the electronic device100is in the free space. Curves b and c are curve diagrams of the return loss coefficient of the antenna40that exists when the electronic device100is held by a hand and the electronic device100is in the portrait mode. The curve b represents a curve diagram of the return loss coefficient of the antenna40that exists when the electronic device100is in the beside head and hand left side mode (namely, a mode in which the electronic device100is held by a left hand and is close to a left side of the face). The curve c represents a curve diagram of the return loss coefficient of the antenna40that exists when the electronic device100is in the beside head and hand right side mode (namely, a mode in which the electronic device100is held by a right hand and is close to a right side of the face).FIG.10is a diagram of system efficiency of the antenna40represented inFIG.9. InFIG.10, a horizontal coordinate is a frequency (unit: GHz), and a vertical coordinate is radiation efficiency (unit: dB).

It may be learned fromFIG.9andFIG.10that when the first end A is located on the second edge12of the frame10, the antenna40has two antenna modes in the free space, and therefore the antenna40has relatively high bandwidth. In addition, in both the beside head and hand left side mode and the beside head and hand right side mode, radiation performance of the antenna40is slightly reduced, but the antenna40does not encounter a death grip. Furthermore, there is a reduction in the radiation efficiency of the antenna40when the radiation efficiency in the beside head and hand mode (including the beside head and hand left side mode or the beside head and hand right side mode) is compared with that in the free space, but the antenna40still has relatively good radiation efficiency.

Refer toFIG.11andFIG.12.FIG.12is a diagram of system efficiency and radiation efficiency existing when the antenna40of an example structure of the electronic device100shown inFIG.3is in the free space and the handheld state. When the electronic device is held by a hand, the electronic device is in a landscape mode shown inFIG.11. In this case, the second edge12of the electronic device100is held by a hand. InFIG.12, a horizontal coordinate is a frequency (unit: GHz), and a vertical coordinate is efficiency (unit: dB). A curve a represents a curve diagram of radiation efficiency of the antenna40that exists when the electronic device100is in the free space. A curve b represents a curve diagram of radiation efficiency of the antenna40that exists when the electronic device100is in the landscape mode and the second edge12of the electronic device100is held by a hand. A curve c represents a curve diagram of system efficiency of the antenna40that exists when the electronic device100is in the free space. A curve d represents a curve diagram of system efficiency of the antenna40that exists when the electronic device100is in the landscape mode and the second edge12of the electronic device100is held by a hand. It may be learned from the curves c and d that when the electronic device100is in the landscape mode, the antenna40does not encounter a death grip when the two opposite second edges12of the electronic device100are held by a hand. In addition, it may be learned from the curves a and b that there is a reduction of approximately 5 dB in the radiation efficiency of the antenna40when the radiation efficiency that exists when the electronic device100is in the handheld state is compared with that in the free space, but the antenna40still has relatively good radiation efficiency.

For example,FIG.13is a diagram of system efficiency and radiation efficiency of the antenna40of the electronic device100shown inFIG.3in different statuses. InFIG.13, a horizontal coordinate is a frequency (unit: GHz), and a vertical coordinate is efficiency (unit: dB). A curve a represents a curve diagram of radiation efficiency of the antenna40that exists when the electronic device100is in the free space. A curve b represents a curve diagram of radiation efficiency of the antenna40that exists when the electronic device100is held by a hand and the first slot111and the second slot121of the frame10are blocked. A curve c represents a curve diagram of system efficiency of the antenna40that exists when the electronic device100is in the free space. A curve d represents a curve diagram of system efficiency of the antenna40that exists when the electronic device100is held by a hand and the first slot111and the second slot121of the frame10are blocked. It may be learned from the curves c and d that when the electronic device100is held by a hand and the first slot111and the second slot121of the frame10are blocked, the antenna40does not encounter a death grip. In addition, it may be learned from the curves a and b that there is a reduction of approximately 7 dB in the radiation efficiency of the antenna40when the radiation efficiency that exists when the electronic device100is in the handheld state and the first slot111and the second slot121of the frame10are blocked is compared with that in the free space, but the antenna40still has relatively good radiation efficiency.

FIG.14is a schematic diagram of a structure of the antenna40according to some other embodiments of this application. A difference between the antenna40in the embodiment shown inFIG.14and that in the embodiment shown inFIG.2lies in that a third tuning element45is connected between the grounding point414of the antenna body41and a grounding position. In this embodiment, the third tuning element45may be a capacitor or an inductor, or may be obtained with a capacitor and an inductor disposed in parallel or disposed in series. The third tuning element45is connected between the grounding point414and the grounding position, to change the electrical length, of the antenna body41, between the first end A and the second end B and the electrical length, of the antenna body41, between the feed point413and the first end A or the second end B, so as to adjust an operating frequency of an antenna mode generated based on resonance of the antenna body41. In this embodiment, the grounding position is a position at which the grounding pin44connects to one end of the middle frame30.

In some embodiments of this application, the antenna40further includes at least one switching circuit. The antenna40switches to different operating frequency bands by using the switching circuit, so that the antenna40can implement communication at a plurality of different operating frequency bands.FIG.15ais a schematic diagram of a structure of the antenna40according to some other embodiments of this application. A difference between the antenna40in the embodiment shown inFIG.15aand that in the embodiment shown inFIG.3lies in that the antenna40further includes a first switching circuit46. A first connection point415is disposed on the antenna body41, and the first connection point415is located on a side that is of the feed point413and the grounding point414and that is far away from the first end A or on a side that is of the feed point413and the grounding point414and that is far away from the second end B. It should be noted that in this application, the first connection point415is not an actual point, and a position at which the first switching circuit46connects to the antenna body41is the first connection point415. The first switching circuit46includes a first switch461and at least one grounded first tuning element462. The first tuning element462may be a capacitive element or an inductive element, or may be obtained with capacitive or inductive elements connected in parallel or connected in series. At least one means one or more. The capacitive or inductive elements connected in parallel or in series mean that the first tuning element462may be obtained with a plurality of capacitive elements disposed in parallel or disposed in series, may be obtained with a plurality of inductive elements connected in parallel or connected in series, or may be obtained with a capacitive element and an inductive element connected in parallel or connected in series. One end of the first switch461connects to the first connection point415, and the other end may connect to different first tuning elements462through switching, to connect different first tuning elements462(which may be first tuning elements462of different types, or may be first tuning elements462that are of a same type and that differ in specification and size) to the antenna body41. In this embodiment, the first connection point415is located on the side that is of the feed point413and the grounding point414and that is far away from the second end B, to change the electrical length between the feed point413and the first end A and the electrical length (the electrical length between the first end A and the second end B) of the antenna body41, so as to change the frequency of the resonance of the first wavelength in the quarter wavelength mode and the frequency of the resonance of the second wavelength in the half wavelength mode, so that the antenna40can cover different operating frequency bands. In some embodiments, the first connection point415may be alternatively located on the side that is of the feed point413and the grounding point414and that is far away from the first end A, to change the electrical length between the feed point413and the second end B and the electrical length between the first end A and the second end B, so as to change the frequency of the resonance of the second wavelength in the half wavelength mode.

The first switch461may be various types of switches. For example, the first switch461may be a physical switch such as a single-pole single-throw switch, a single-pole multi-throw switch, or a multi-pole multi-throw switch, or may be a switchable interface such as a mobile industry processor interface (MIPI) or a general-purpose input/output (GPIO) interface. The first switch461includes a first movable end461aand a plurality of first fixed ends461b. One end that is of the first movable end461aand that is far away from the first fixed end461bconnects to the first connection point415, and the other end may electrically connect to the first fixed ends461bthrough switching. One end of the first tuning element462connects to the first fixed end461b, and the other end is grounded. When the first movable end461aconnects to different first fixed ends461bthrough switching, different first tuning elements462connect to the antenna body41, to adjust the electrical length of the antenna body41, so as to change the frequency of the resonance of the first wavelength in the quarter wavelength mode and the frequency of the resonance of the second wavelength in the half wavelength mode. Based on different types of first switches461, the first switch461may include one or more first movable ends461a. Switching between different first fixed ends461bis performed for different first movable ends461a, so that a size, a type, and a quantity of first tuning elements462that connect to the antenna body41can be changed. For example, in the embodiment shown inFIG.15a, the first switch461is a single-pole multi-throw switch, that is, the first switch461includes a plurality of first fixed ends461b. Each first fixed end461bconnects to one first tuning element462, and different first fixed ends461bconnect to different first tuning elements462(which may differ in type or specification and size). Therefore, when the first movable end461aof the first switch461connects to a different first fixed end461bthrough switching, the antenna body41connects to a different first tuning element462, to change an electrical length of each section (including the section between the feed point413and the first end A, a section between the first end A and the second end B, or the like) of the antenna body41. In this way, the antenna40can switch between different operating frequency bands based on an actual requirement, so that the antenna40of the electronic device100can cover more operating frequency bands. For example, in the embodiment shown inFIG.15a, there are specifically four first fixed ends461b, and the four first fixed ends461brespectively connect to inductors of different sizes and then are grounded. When the first movable end461aconnects to another first fixed end461bthrough switching from a first fixed end461b, the electrical length between the feed point413and the first end A is changed, and therefore the frequency of the resonance that is of the first wavelength in the quarter wavelength mode and that is generated between the feed point413and the first end A is changed. In addition, the electrical length between the first end A and the second end B is changed, and therefore the frequency of the resonance that is of the second wavelength in the half wavelength mode and that is of the antenna40is changed.

FIG.15bis another schematic diagram of a structure of the antenna40according to this application. In this embodiment, the first switch461is a multi-pole multi-throw switch, and a quantity of first movable ends461ais the same as a quantity of first fixed ends461b. Specifically, in this embodiment, there are four first movable ends461aand four first fixed ends461b, and the first movable ends461aare in a one-to-one correspondence with the first fixed ends461b. One end of each of the four first movable ends461aconnects to the first connection point415, and the other end connects to or is disconnected from a first fixed end461bcorresponding to the first movable end461a. In this way, a quantity of first tuning elements462that connect to the antenna body41can be controlled, to change the electrical length between the feed point413and the first end A of the antenna body41and the overall electrical length between the first end A and the second end B, so as to change the frequency of the resonance of the first wavelength in the quarter wavelength mode and the frequency of the resonance of the second wavelength in the half wavelength mode. For example, when two first movable ends461aconnect to first fixed ends461bcorresponding to the two first movable ends461a, and the other two first movable ends461aare disconnected from first fixed ends461bcorresponding to the other two first movable ends461a, two first tuning elements462connect to the antenna body41, and the two first tuning elements462are disposed in parallel.

FIG.16is a schematic diagram of a structure of the antenna40according to some other embodiments of this application. A difference between the embodiment shown inFIG.16and the embodiment shown inFIG.15alies in that the antenna40further includes a second switching circuit47. A second connection point416is disposed on the antenna body41, and the second switching circuit47connects to the second connection point416. It should be noted that in this application, the second connection point416is not an actual point, and a position at which the second switching circuit47connects to the antenna body41is the second connection point416. The feed point413and the grounding point414are located between the first connection point415and the second connection point416. The second switching circuit47is of a structure similar to that of the first switching circuit46, and includes a second switch471and a plurality of second tuning elements472. The second switch471may connect to different second tuning elements472through switching. The first switching circuit46cooperates with the second switching circuit47, to change the operating frequency of the resonance of the first wavelength in the quarter wavelength mode and the operating frequency of the resonance of the second wavelength in the half wavelength mode. Specifically, switching is performed for the first switch461of the first switching circuit46, so that different first tuning elements462connect to the antenna body41, and the second switch471of the second switching circuit47connects to different second tuning elements472through switching, to change the electrical length between the feed point413and the first end A or the second end B and the electrical length between the first end A and the second end B, so as to change the operating frequency of the resonance of the first wavelength in the quarter wavelength mode and the operating frequency of the resonance of the second wavelength in the half wavelength mode. In this way, the antenna40can cover more operating frequency bands. In this embodiment, the second switching circuit47is located on the side that is of the feed point413and the grounding point414and that is far away from the first end A, and the second switch471of the second switching circuit47connects to different second tuning elements472through switching, to change the electrical length between the feed point413and the second end B and the electrical length between the first end A and the second end B, so as to change the frequency of the resonance that is of the second wavelength in the half wavelength mode and that is of the antenna40by using the second switching circuit47.

The second switch471may also be a physical switch such as a single-pole single-throw switch, a single-pole multi-throw switch, or a multi-pole multi-throw switch, or may be a switchable interface such as a mobile industry processor interface (Mobile Industry Processor Interface, MIPI) or a general-purpose input/output (General-purpose input/output, GPIO) interface. In this embodiment, the second switch471is a single-pole multi-throw switch, and includes a second movable end471aand a plurality of second fixed ends471b. One end of each second tuning element472correspondingly connects to one second fixed end471b, and the other end is grounded. One end of the second movable end471aconnects to the second connection point416, and the other end may connect to different second tuning elements472through switching.

In some embodiments, second tuning elements472that connect to the second fixed ends471bof the second switching circuit47are in a one-to-one correspondence with first tuning elements462that connect to the first fixed ends461bof the first switching circuit46. When the first switch461connects to any first tuning element462through switching, the second switch471connects, through switching, to a second tuning element472corresponding to the first tuning element462that connects to the first switch461, to correspondingly adjust the electrical length of each section of the antenna40, so that the electrical length between the feed point413and the first end A can always be greater than the electrical length between the feed point413and the second end B, and it is ensured that the operating frequency of the resonance of the first wavelength in the quarter wavelength mode is less than the frequency of the resonance of the second wavelength in the half wavelength mode, and the difference between the frequency of the resonance of the first wavelength in the quarter wavelength mode and the frequency of the resonance of the second wavelength in the half wavelength mode ranges from 50 MHz to 200 MHz.

FIG.17andFIG.18are respectively a diagram of a return loss and a diagram of system efficiency and radiation efficiency that exist when the first movable end461aof the first switch461of the antenna40shown inFIG.16separately connects to three different first tuning elements462through switching and the second switch471switch correspondingly connects, through switching, to second tuning elements472corresponding to the first tuning elements462that connect to the first switch461. InFIG.17, a horizontal coordinate is a frequency (unit: GHz), and a vertical coordinate is a return loss coefficient (unit: dB). InFIG.18, a horizontal coordinate is a frequency (unit: GHz), and a vertical coordinate is efficiency (unit: dB).

It may be learned fromFIG.17that switching is performed for the first switch461and switching is correspondingly performed for the second switch471, so that the antenna40can generate return loss curves at three different frequency bands. Specifically, curves a, b, and c inFIG.17respectively represent return loss curves generated by the antenna40at antenna bands B28 (from 703 MHz to 803 MHz), B5 (from 824 MHz to 894 MHz), and B8 (from 880 MHz to 960 MHz) when the electronic device100is in the free space. It may be learned fromFIG.17that the antenna40can resonate at different operating frequency bands by performing switching for the first switch461and the second switch471. In addition, the antenna40can generate two antenna modes (the resonance of the first wavelength in the quarter wavelength mode and the resonance of the second wavelength in the half wavelength mode) at different operating frequency bands. Therefore, the antenna40can have relatively high radiation performance both in the free space and in the beside head and hand mode. It may be further learned from the figure that when switching is performed for the first switch461and the second switch471, and it is set that the first tuning element462that connects to the first switch461corresponds to the second tuning element472that connects to the second switch471, the frequency of the resonance that is of the first wavelength in the quarter wavelength mode and that is of the antenna40is always less than the frequency of the resonance of the second wavelength in the half wavelength mode, and the difference between the frequency of the resonance of the first wavelength in the quarter wavelength mode and the frequency of the resonance of the second wavelength in the half wavelength mode ranges from 50 MHz to 200 MHz. InFIG.18, curves a, b, and c respectively represent curve diagrams of radiation efficiency that are generated by the antenna40at the antenna frequency bands B28 (from 703 MHz to 803 MHz), B5 (from 824 MHz to 894 MHz), and B8 (from 880 MHz to 960 MHz) when the electronic device100is in the free space, and curves d, e, and f respectively represent curve diagrams of system efficiency that are generated by the antenna40at the antenna frequency bands B28, B5, and B8. It may be learned fromFIG.18that at bandwidth of 80 MHz of each of different operating frequency bands (including B28, B5, and B8), efficiency of the antenna40is less than −6 dB, and therefore the antenna40has good radiation performance.

In this embodiment, the first switch461of the first switching circuit46and the second switching circuit47is a single-pole four-throw switch, so that the antenna40can cover four different operating frequencies. It may be understood that based on an actual requirement, the antenna40can cover more operating frequency bands by increasing a quantity of switching circuits, by using different first switches461and second switches471, or the like. For example, in some embodiments, the first switch461of the first switching circuit46and the second switching circuit47is a multi-pole four-throw switch, so that the antenna40can cover24operating frequencies.

The foregoing descriptions are preferred implementations of this application. It should be noted that a person of ordinary skill in the art may further make several improvements or polishing without departing from the principle of this application and the improvements or polishing shall fall within the protection scope of this application.