WO2021082560A1

WO2021082560A1 - Foldable electronic device

Info

Publication number: WO2021082560A1
Application number: PCT/CN2020/105111
Authority: WO
Inventors: 王岩; 刘华涛; 应李俊; 尤佳庆; 余冬; 李建铭; 王汉阳
Original assignee: 华为技术有限公司
Priority date: 2019-10-31
Filing date: 2020-07-28
Publication date: 2021-05-06
Also published as: CN112751160B; CN112751160A

Abstract

The present application discloses a foldable electronic device, comprising an antenna system, the antenna system comprising an antenna ground plane, a first antenna and a second antenna. The antenna ground plane is divided, by a rotary shaft, into a first antenna ground plane part and a second antenna ground plane part which are unfolded or folded with respect to each other. The first antenna and the second antenna are respectively provided corresponding to the first antenna ground plane part and the second antenna ground plane part. The first antenna comprises a first antenna radiator and a first grounded capacitor, the first antenna radiator having a first branch. The second antenna comprises a second antenna radiator and a second grounded capacitor, the second antenna radiator having a second branch. According to the present application, for a pair of antennas: in an unfolded state, two antennas of the pair of antennas work separately; in a folded state, even in cases where the two antennas of the pair of antennas are close to each other or partially overlap with each other, the two antennas of the pair of antennas have high isolation and a low envelope correlation coefficient, and still work normally.

Description

Foldable electronic equipment

This application claims the priority of the Chinese patent application filed on October 31, 2019 with the application number CN201911056688.4 and the invention title "Foldable Electronic Equipment", the entire content of which is incorporated into this application by reference.

Technical field

This application relates to the field of wireless communication antennas, and in particular to a foldable electronic device.

Background technique

After mobile phones entered the smart era, candy bar smart phones, as a form of mobile phones, have existed in the consumer market for a long time. In order to bring a more comfortable and convenient experience to mobile phone/mobile terminal device users, foldable smartphones are a hot topic now. Major mobile phone manufacturers, such as Samsung, ZTE, Motorola, Huawei, etc., have already released related foldable smartphones, and companies such as OPPO/VIVO, Xiaomi, and Apple are also rumored to release foldable smartphones.

Foldable smartphones have two or more working states, and the two commonly used working states are: unfolded state and folded state. The unfolded state is the common candy bar smart phone at present, and the folded state is to rotate the candy bar smart phone 180 degrees along the axis to close the lid. For the antenna design of the foldable smart phone in the unfolded state, it is similar to the current candy bar smart phone design, and the current design scheme can be used. However, for the antenna design in the folded state, the relative position between the antennas may change. When the distance between the antennas is close, the isolation of the antenna will be lower, and the envelope correlation coefficient (Envelope Correlation Coefficient) will be lower. Correlation Coefficient, referred to as "ECC") is high, and the transmission/reception performance of the entire antenna device may be degraded. Therefore, for the antenna design of the foldable smart phone in the folded state, the antennas are closer. How to design high isolation and low envelope correlation coefficient is the difficulty and pain point of the foldable smart phone antenna design.

Based on the difficulties and pain points of the foldable smart phone antenna design, in the antenna design of the foldable smart phone in the prior art, usually two antennas can work at the same time in the unfolded state, and only one antenna can work normally in the folded state Therefore, the number of antennas that can work when the foldable smart phone is in the folded state is reduced compared to the number of antennas that can work in the unfolded state.

For example, US patent application US10079425B2 discloses an antenna device for a portable terminal. The portable terminal is a foldable smart phone. As shown in FIG. 1, the portable terminal 100 has the antenna device. The antenna device includes a flexible display element. On the first antenna element 131 and the second antenna element 133. The display element includes a first area 101 and a second area 102 that can be folded to face each other. The first antenna element 131 is arranged on one side of the first area 101, and the second antenna element 133 is arranged on one side of the second area 102. The circuit board 103 is provided in the central part of the display element. Each of the first antenna element 131 and the second antenna element 133 extends in the longitudinal direction of the display element and extends in a direction away from the circuit board 103. When the display element is in the folded state, the first antenna element 131 and the second antenna element 133 may at least partially overlap. When the display element is in the unfolded state, both the first antenna element 131 and the second antenna element 133 work normally. When the display element is in the folded state, the switch element 135 is cut off, and the antenna device is configured as a monopole antenna formed by only the first antenna element 131, that is, only the first antenna element 131 works, and the second antenna element 133 does not work.

Therefore, the portable terminal adopting the antenna device of this structure can have two antennas working at the same time in the unfolded state, but only one antenna can work normally in the folded state, so that the portable terminal can work in the folded state. The number is reduced relative to the number of antennas that can work in the unfolded state.

Summary of the invention

The purpose of this application is to solve the problem that the number of antennas that can work in the folded state of the foldable electronic device in the prior art is reduced relative to the number of antennas that can work in the unfolded state. Therefore, the embodiments of the present application provide a foldable electronic device, which overcomes the pain points and difficulties of the existing foldable electronic device antenna design, and can make a pair of antennas: in the unfolded state, the two antennas of the pair of antennas are independent. Work; in the folded state, even when the two antennas of the pair of antennas are close or even partially overlapped (not in contact), the two antennas of the pair of antennas have a higher degree of isolation and a relatively high degree of isolation between the two antennas. The low envelope correlation coefficient (ECC) still works normally, that is, the self-decoupling of the pair of antennas is realized.

An embodiment of the present application provides a foldable electronic device, including an antenna system, and the antenna system includes:

The antenna floor is divided into a first antenna floor part and a second antenna floor part that are mutually expanded or folded by a rotating shaft;

The first antenna includes a first antenna radiator and a first grounding capacitor, at least part of the first antenna radiator is located outside the edge of a side of the first antenna floor part away from the rotation axis, and the first antenna radiates The body includes a first end and a second end, and has a first antenna feed point between the first end and the second end, and a first antenna feed point between the first antenna feed point and the second end. The first connection point between the first connection point and the second end, the first antenna radiator part located between the first connection point and the second end is the first stub, and the first antenna feed point is connected to the The first antenna floor part forms a ground point of the first feed, and the first antenna radiator is connected to the first antenna floor part through the first ground capacitor at the first connection point , And form the ground point of the first grounding capacitor; the first antenna feed point and the ground point of the first feed source are located on one side of the center line of the antenna floor, and the first connection point is opposite to the The first antenna feed point is closer to the center line, and the ground point of the first grounding capacitor is closer to the center line relative to the ground point of the first feed; wherein, the center line is perpendicular to the center line. The axis direction of the shaft;

The second antenna includes a second antenna radiator and a second grounding capacitor, at least part of the second antenna radiator is located outside the edge of a side of the second antenna floor part away from the rotation axis, and the second antenna radiates The body includes a first end and a second end, and has a second antenna feed point between the first end and the second end, and a second antenna feed point between the second antenna feed point and the second end. The second connection point between the second connection point and the second end, the second antenna radiator part located between the second connection point and the second end is the second stub, and the second antenna feed point is connected to the all through the second feed source The second antenna floor part forms a ground point of the second feed source, and the second antenna radiator is connected to the second antenna floor part through the second grounding capacitor at the second connection point, And form the ground point of the second grounding capacitor; the second antenna feed point and the ground point of the second feed are located on the other side of the center line opposite to the one side, and the second connection The point is closer to the center line than the second antenna feed point, and the ground point of the second grounding capacitor is closer to the center line than the ground point of the second feed source.

In the foldable electronic device of the present application, the pain points and difficulties of the existing foldable electronic device antenna design are overcome, and the first antenna radiator is connected to the first antenna floor part through the first grounding capacitor at an appropriate position, and The first branch is set, and at the same time, the second antenna radiator is connected to the second antenna floor part through the second grounding capacitor at the appropriate position, and the second branch is set to make a pair of antennas: when the antenna floor is in the unfolded state, The first antenna radiator and the second antenna radiator can work independently. When the antenna floor is folded, even if the distance between the first antenna radiator and the second antenna radiator is close or even partially overlapped (but not in contact with each other) ), the first antenna radiator and the second antenna radiator have higher isolation and lower envelope correlation coefficient (ECC), which improves the antenna’s radiation efficiency and diversity gain, making the first antenna radiator The antenna radiator and the second antenna radiator still work normally, that is, the self-decoupling of the pair of antennas is realized.

In some embodiments, the current of the first antenna radiator passing through the first grounding capacitor forms a first floor current flowing in a first direction and a second floor current flowing in a second direction in the first antenna floor portion. Floor current, the first direction is opposite to the second direction; the current flowing on the first branch forms a third floor current flowing in the first direction on the first antenna floor portion, the The amplitudes of the second floor current and the third floor current are approximately equal;

The current of the second antenna radiator through the second grounding capacitor forms a fourth floor current flowing in the first direction and a fifth floor current flowing in the second direction in the second antenna floor portion The current flowing on the second branch forms a sixth floor current flowing in the second direction on the second antenna floor portion, and the amplitude of the fourth floor current and the sixth floor current are substantially equal.

In this solution, the amplitude of the second floor current and the third floor current are approximately the same, and the directions are opposite, so that a small amount of floor current on the floor of the first antenna will flow in the second direction. At the same time, the fourth floor current and The magnitude of the sixth floor current is approximately the same, and the direction is opposite, so that little floor current on the second antenna floor part will flow in the first direction, so that the first antenna radiator and the second antenna radiator can be folded in the folded state. It has higher isolation and lower envelope correlation coefficient (ECC).

In some embodiments, the first connection point, the first antenna feed point, the ground point of the first grounding capacitor, and the ground point of the first feed are located on one side of a virtual line, so The second connection point, the second antenna feed point, the ground point of the second grounding capacitor, and the ground point of the second feed source are located on the other side of the virtual line; wherein, the virtual line Is the centerline or parallel to the centerline.

In this solution, the above structure is adopted, which can reduce the floor current formed by the first antenna radiator on the first antenna floor part and the floor current formed by the second antenna radiator on the second antenna floor part in the folded state. The overlapped current intensity avoids the deterioration of the isolation and envelope correlation coefficient between the first antenna radiator and the second antenna radiator during use.

In some possible embodiments, when the first antenna floor part and the second antenna floor part are folded with each other, the distance between the first connection point and the first antenna feed point is smaller than that of the second antenna floor part. The distance between the connection point and the first antenna feed point, and the distance between the ground point of the first grounding capacitor and the ground point of the first feed source is less than the distance between the ground point of the second grounding capacitor and the first antenna The distance to the ground point of a feed. The distance between the second connection point and the second antenna feed point is less than the distance between the first connection point and the second antenna feed point, and the ground point of the second grounding capacitor is away from the first antenna feed point. The distance between the ground point of the two feed sources is smaller than the distance between the ground point of the first grounding capacitor and the ground point of the second feed source.

In some embodiments, the first antenna radiator further has a first preset point between the first antenna feed point and the first connection point, and the first preset point is connected to the first connection point. The distance between the first connection points is less than or equal to 10 mm; the second antenna radiator also has a second preset point between the second antenna feed point and the second connection point, and the first 2. The distance between the preset point and the second connection point is less than or equal to 10 mm;

When the first antenna floor part and the second antenna floor part are folded with each other, the second end of the first antenna radiator extends to no more than For the position of the second predetermined point, the second end of the second antenna radiator extends to a position that does not exceed the first predetermined point.

In this solution, the above structure is adopted, which can further reduce the floor current formed by the first antenna radiator on the first antenna floor part and the floor current formed by the second antenna radiator on the second antenna floor part in the folded state. The current intensity overlaps the current, so as to avoid the deterioration of the isolation and the envelope correlation coefficient between the first antenna radiator and the second antenna radiator during use.

In some possible embodiments, the distance between the first preset point and the first connection point is less than or equal to 2 mm; the distance between the second preset point and the second connection point is less than Or equal to 2mm.

In some possible embodiments, when the first antenna floor part and the second antenna floor part are folded with each other, they are located at the first preset point and in a direction parallel to the axial direction of the rotating shaft. The first antenna radiator part between the second end of the first antenna radiator and the second antenna radiator part between the second preset point and the second end of the second antenna radiator The antenna radiators partially overlap or are separated and spaced apart, and the first antenna radiator part located between the first preset point and the first end of the first antenna radiator and the first antenna radiator part located at the second preset The second antenna radiator between the dot and the first end of the second antenna radiator is partially separated.

In some embodiments, the working frequency band of the first antenna radiator and the working frequency band of the second antenna radiator are the same or partially overlapped.

In some embodiments, the working frequency band of the first antenna radiator is 700-960MHz, the working frequency band of the second antenna radiator is 700-960MHz; the length of the first branch is 10-30mm, The length of the two branches is 10-30 mm; the capacitance value of the first grounding capacitor is 1-5 pF, and the capacitance value of the second grounding capacitor is 1-5 pF.

In some embodiments, the first antenna radiator extends along the side edge of the first antenna floor portion; the second antenna radiator extends along the side edge of the second antenna floor portion Extend in a straight line.

In some embodiments, the first antenna radiator is also located near a pair of corners of the first antenna floor portion away from the rotation axis, and has a shape along the corner edge of the first antenna floor portion. Extend in a bent shape, and the first antenna radiator has a first straight line segment extending along the side edge of the first antenna floor portion, and the first straight line segment includes the first branch;

The second antenna radiator is also located near a pair of corners of the second antenna floor portion away from the rotation axis, and extends in a bent shape along the corner edge of the second antenna floor portion, and The second antenna radiator has a first straight section extending along the side edge of the second antenna floor portion, and the first straight section of the second antenna radiator includes the second branch;

When the first antenna floor portion and the second antenna floor portion are spread out from each other, the diagonal corner of the first antenna floor portion and the diagonal corner of the second antenna floor portion are disposed opposite to each other.

In some embodiments, the first antenna radiator further includes a second straight line segment, and the second straight line segment is perpendicularly connected to the first straight line segment of the first antenna radiator and is away from the first branch. One end

The second antenna radiator further includes a second straight line segment, and the second straight line segment of the second antenna radiator is perpendicularly connected to the first straight line segment of the second antenna radiator away from the second One end of the branch.

In some embodiments, the first grounding capacitor and the second grounding capacitor are both adjustable capacitors. By adjusting the capacitance values of the first grounding capacitor and the second grounding capacitor, the first antenna radiator and the second grounding capacitor are adjusted. The isolation and envelope correlation coefficient of the two antenna radiators. In this way, the capacitance values of the first grounding capacitor and the second grounding capacitor can be adjusted to match the lengths of the first stub and the second stub respectively, so that the distance between the first antenna radiator and the second antenna radiator Higher isolation and lower envelope correlation coefficient.

In some embodiments, the first antenna further includes a first switch connected between the first antenna radiator and the first antenna floor portion, and is switched by the first switch So that the first antenna radiator works in different sub-frequency bands; the second antenna further includes a second switch connected between the second antenna radiator and the second antenna floor part , Through the switching of the second switch, the second antenna radiator works in different sub-bands.

Through the switching of the first switch and the second switch, the working frequency bands of the first antenna radiator and the second antenna radiator can be switched to different sub-frequency bands according to actual needs. When the antenna works in different frequency bands, in order to achieve the best isolation and envelope correlation coefficient (ECC), the first grounding capacitor and the second grounding capacitor also work at corresponding capacitance values. That is to say, it can work in different frequency bands by switching, so as to realize the performance of each frequency band in the folded state similar to the unfolded state.

In some embodiments, the first switch and the second switch are both single-pole multi-throw switches, so that the first switch corresponds to the multiple sub-bands in which the first antenna radiator operates, and the second switch Corresponding to multiple sub-bands in which the second antenna radiator works.

In some embodiments, the plurality of sub-bands in which the first antenna radiator works and the plurality of sub-bands in which the second antenna radiator works include a first sub-band, a second sub-band, and a third sub-band. Frequency band and the fourth sub-band;

The frequency range of the first sub-band is 704-788 MHz; the frequency range of the second sub-band is 791-860 MHz; the frequency range of the third sub-band is 824-894 MHz; and the frequency range of the fourth sub-band is 880-960 MHz.

In some embodiments, the portion of the first antenna radiator located between the first antenna feed point and the first end of the first antenna radiator is a first extension, and the first switch is connected to Between the first extension and the first antenna floor part; the second antenna radiator part located between the second antenna feed point and the first end of the second antenna radiator Is a second extension section, and the second switch is connected between the second extension section and the second antenna floor portion.

Description of the drawings

In order to more clearly illustrate the specific embodiments of this application or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the specific embodiments or the description of the prior art. Obviously, the appendix in the following description The drawings are some embodiments of the application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

1 is a schematic structural diagram of a conventional portable terminal with an antenna device, in which the figure on the left is a schematic structural diagram of the portable terminal in an unfolded state, and the figure on the right is a schematic structural diagram of the portable terminal in a folded state;

FIG. 2a is a schematic structural diagram of an implementation manner of an antenna system of a foldable electronic device according to an embodiment of the application, in which the antenna floor is in an unfolded state;

2b is a schematic structural diagram of an implementation manner of an antenna system of a foldable electronic device according to an embodiment of the application, in which the antenna floor is in a folded state;

Figure 3a is the S parameter performance of the first antenna radiator and the second antenna radiator in the working frequency range measured when the antenna floor of the foldable electronic device antenna system of the embodiment of the application is in the unfolded state and the folded state. A simulation graph, the frequency range of the working frequency band of the first antenna radiator and the second antenna radiator is 824-894MHz;

Figure 3b is the ECC (including ECC) of the first antenna radiator and the second antenna radiator in the working frequency range measured when the antenna floor of the foldable electronic device antenna system of the embodiment of the application is in the unfolded state and the folded state. The network correlation coefficient) parameter performance simulation graph, the frequency range of the working frequency band of the first antenna radiator and the second antenna radiator is 824-894MHz;

Figure 4a is a schematic structural diagram of the antenna system of the first reference design, in which the first branch and the second branch are removed on the basis of the antenna system of the present application;

Figure 4b is a schematic structural diagram of the antenna system of the second reference design, in which the first grounding capacitor and the second grounding capacitor are removed on the basis of the antenna system of the present application, so that the first antenna radiator and the second antenna radiator pass Connecting ribs are directly connected to the antenna floor;

Figure 4c is a schematic structural diagram of the antenna system of the third reference design, in which, on the basis of the antenna system of the present application, the first branch and the second branch are removed, and the first grounding capacitor and the second grounding capacitor are removed, so that the first An antenna radiator and a second antenna radiator are directly connected to the antenna floor through connecting ribs;

Figure 5a is the S parameter performance simulation curve of the first antenna radiator and the second antenna radiator in the working frequency range measured when the antenna floor of the antenna system of the three reference designs is in the folded state. This application and three The frequency range of the working frequency band of the first antenna radiator and the second antenna radiator of the antenna system of the reference design is 824-894MHz;

Figure 5b is the performance simulation of the ECC (Envelope Correlation Coefficient) parameters of the first antenna radiator and the second antenna radiator in the working frequency range measured when the antenna floor of the antenna system of this application and three reference designs is in a folded state In the graph, the frequency range of the working frequency band of the first antenna radiator and the second antenna radiator of the antenna system of the present application and the three reference designs is 824-894MHz;

FIG. 6a is a partial structural diagram of an implementation manner of an antenna system of a foldable electronic device according to an embodiment of the application, in which only the first antenna is retained, and the antenna floor is in an unfolded state;

Fig. 6b is a partial structural diagram of the antenna system of the first reference design, in which only the first antenna is reserved and the antenna floor is in an unfolded state;

Fig. 6c is a partial structural diagram of the antenna system of the second reference design, in which only the first antenna is reserved and the antenna floor is in an unfolded state;

Figures 7a-7c are schematic diagrams of the current distribution on the antenna floor of the first antenna radiator of the antenna system of the present application, the first reference design and the second reference design in Figures 6a-6c, respectively, at the same operating frequency ；

Fig. 8 is a schematic diagram of equivalent current distribution on the antenna floor of the first antenna radiator of the antenna system in Fig. 6a;

FIG. 9 is a schematic structural diagram of another implementation manner of an antenna system of a foldable electronic device according to an embodiment of the application, in which the antenna floor is in an unfolded state;

FIG. 10a is a simulation curve diagram of S-parameter performance of the first antenna radiator and the second antenna radiator in the three sub-frequency bands in which the antenna system of the foldable electronic device according to an embodiment of the application is in a folded state measured when the antenna floor is in a folded state;

Fig. 10b is a graph showing the performance simulation curves of ECC parameters of the first antenna radiator and the second antenna radiator in the three sub-bands in which the antenna system of the foldable electronic device according to the embodiment of the application is in a folded state.

Description of reference signs:

current technology:

100: portable terminal;

101: The first area

102: The second area

103: Circuit board

131: The first antenna element

133: The second antenna element

135: Switching element

This application:

100: Antenna system;

200: antenna floor; 210: first antenna floor part; 212: upper side edge; 214: diagonal; 220: second antenna floor part; 222: lower side edge; 224: diagonal; 230: rotating shaft;

300: the first antenna;

400: the first antenna radiator; 402: the first antenna feed point; 404: the first connection point; 406: the first stub; 408: the first straight line segment; 410: the second straight line segment; 412: the first end 414: the second end; 416: the first preset point;

420: the first grounding capacitor; 422: the grounding point of the first grounding capacitor;

440: the first feed; 442: the ground point of the first feed;

500: second antenna;

600: second antenna radiator; 602: second antenna feed point; 604: second connection point; 606: second branch; 608: first straight line segment; 610: second straight line segment; 612: first end; 614: the second end; 616: the second preset point;

620: the second grounding capacitor; 622: the grounding point of the second grounding capacitor;

640: the second feed; 642: the ground point of the second feed;

700: the first switch; 720: the first capacitor; 740: the first inductor;

800: the second switch; 820: the second capacitor; 840: the second inductor;

O1: center line;

O2: axis direction;

d1: the length of the first straight line segment;

d11: the length of the other part of the first straight line except the first branch;

d12: the length of the first branch;

d13: the distance between the end of the first straight line away from the first stub and the left edge of the first antenna floor part;

d14: the distance between the first connection point and the center line;

d15: the distance between one end of the first branch and the center line;

d2: the length of the second straight line segment;

d21: the distance from one end of the second straight line connecting the first straight line to the feeding point of the first antenna;

d22: the distance from the feeding point of the first antenna to the end of the second straight line segment away from the first straight line segment;

d23: the distance between the first connection point and the grounding point of the first grounding capacitor;

d3: the length of the first antenna floor part;

d4: The width of the first antenna floor section.

Detailed ways

The following specific specific examples illustrate the implementation of the present application, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. Although the description of this application will be introduced in conjunction with the preferred embodiments, this does not mean that the features of this application are limited to this embodiment. On the contrary, the purpose of introducing the application in combination with the embodiments is to cover other options or modifications that may be extended based on the claims of this application. In order to provide an in-depth understanding of the application, the following description will contain many specific details. This application can also be implemented without using these details. In addition, in order to avoid confusion or obscuring the focus of this application, some specific details will be omitted in the description. It should be noted that the embodiments in this application and the features in the embodiments can be combined with each other if there is no conflict.

It should be noted that in this specification, similar reference numerals and letters indicate similar items in the following drawings. Therefore, once a certain item is defined in one drawing, it is not necessary to refer to it in subsequent drawings. To further define and explain.

The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

In the description of this application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the pointed device or element must have a specific orientation or a specific orientation. The structure and operation cannot therefore be understood as a limitation of this application. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance.

In the description of this application, it should be noted that the terms "installation", "connection", and "connection" should be understood in a broad sense, unless otherwise clearly specified and limited. For example, it can be a fixed connection or a detachable connection. Connected or integrally connected; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication between two components. For those of ordinary skill in the art, the specific meanings of the above-mentioned terms in this application can be understood under specific circumstances.

In order to make the objectives, technical solutions, and advantages of the present application clearer, the implementation manners of the present application will be further described in detail below with reference to the accompanying drawings.

The present application provides a foldable electronic device, which includes an antenna system. In this embodiment, the foldable electronic device is illustrated as a foldable smartphone. Of course, those skilled in the art can understand that, in other alternative embodiments, the foldable electronic device may also be a foldable tablet computer or a foldable smart watch, and other foldable electronic devices. The scope of protection has a limiting effect.

Please refer to FIGS. 2a-2b. FIG. 2a shows a schematic structure of an embodiment of an antenna system 100 for a foldable electronic device according to an embodiment of the present application. The antenna floor 200 is in an unfolded state. At this time, the antenna floor 200 The first antenna floor part 210 and the second antenna floor part 220 are spread out from each other. Fig. 2b shows a schematic structure of an antenna system 100 according to an embodiment of the present application, in which the antenna floor 200 is in a folded state. At this time, the first antenna floor portion 210 and the second antenna floor portion 220 of the antenna floor 200 are mutually folded . The antenna system 100 is applied to a foldable electronic device. The foldable electronic device may be a foldable smart phone, a foldable tablet computer, a foldable smart watch, or the like.

As shown in FIGS. 2a-2b, the antenna system 100 includes an antenna floor 200, a first antenna 300, and a second antenna 500. The antenna floor 200 is divided into a first antenna floor part 210 and a second antenna floor part 220 that are mutually expanded or folded by a rotating shaft 230. The first antenna 300 is arranged corresponding to the first antenna floor part 210, and the second antenna 500 is arranged corresponding to the second antenna floor part 220.

As shown in Fig. 2a, when the antenna floor 200 is in an unfolded state, that is, when the first antenna floor portion 210 and the second antenna floor portion 220 are deployed mutually, the first antenna floor portion 210 and the second antenna floor portion 220 are located on the same plane, And the first antenna 300 is located outside the side edge of the first antenna floor part 210 away from the rotating shaft 230 (that is, the upper side edge 212 in FIG. 2a), and the second antenna 500 is located at the side edge of the second antenna floor part 220 away from the rotating shaft 230. (Ie the lower edge 222 in Figure 2a) outside. That is to say, when the antenna floor 200 is in the unfolded state, the first antenna 300 and the second antenna 500 are respectively located on the opposite side edges of the antenna floor 200 away from the rotation axis 230 (ie, the upper edge 212 and the upper edge of the antenna floor 200 in FIG. 2a). The lower edge 222 and the upper edge 212 are located on the first antenna floor portion 210, and the lower edge 222 is located outside the second antenna floor portion 220), that is, the first antenna 300 is located on the top of the first antenna floor portion 210, and the second The antenna 500 is located at the bottom of the second antenna floor part 220.

As shown in Fig. 2b, when the antenna floor 200 is in a folded state, that is, when the first antenna floor part 210 and the second antenna floor part 220 are folded with each other, the first antenna floor part 210 and the second antenna floor part 220 are arranged oppositely, The upper side edge 212 of the first antenna floor part 210 and the lower side edge 222 of the second antenna floor part 220 are opposed to each other in a direction perpendicular to the antenna floor 200. At this time, the first antenna 300 and the second antenna 500 are located on the same side of the antenna floor 200 away from the rotating shaft 230, and the distance between the first antenna 300 and the second antenna 500 is relatively close, but the first antenna 300 and the second antenna 500 The antenna 500 is not in contact.

Specifically, as shown in FIG. 2a, the center line O1 of the antenna floor 200 is perpendicular to the axial direction O2 of the rotating shaft 230. Through the center line O1, the first antenna floor part 210 and the second antenna floor part 220 are respectively divided into two parts that are symmetrical and the same (including the same structure and size).

Further, the first antenna floor part 210 and the second antenna floor part 220 divided into the antenna floor 200 by the rotation axis 230 are symmetrical about the rotation axis 230, and the structures and sizes of the first antenna floor part 210 and the second antenna floor part 220 are the same . It should be noted that those skilled in the art can understand that the structure of the first antenna floor part 210 and the second antenna floor part 220 can be different, and the size can also be different, and can be set according to actual needs. The scope of protection has a limiting effect.

In this embodiment, the antenna floor 200 has a square plate structure. It should be noted that those skilled in the art can understand that the antenna floor 200 may also be a structure with other suitable shapes.

In this embodiment, the antenna floor 200 may be formed by the bottom plate of the middle frame of a foldable electronic device (that is, a foldable smart phone). Those skilled in the art can understand that, in other alternative embodiments, the antenna floor 200 may also be composed of other metal parts, such as a printed circuit board.

As shown in FIG. 2a, the first antenna 300 includes a first antenna radiator 400 and a first grounding capacitor 420. A part of the first antenna radiator 400 is located outside the side edge of the first antenna floor portion 210 away from the rotating shaft 230 (ie, the upper side edge 212 in FIG. 2a). In other words, a part of the first antenna radiator 400 is located outside the upper edge 212 of the first antenna floor portion 210 away from the rotating shaft 230, and the extending direction of the upper edge 212 is parallel to the axial direction O2 of the rotating shaft 230. It can be seen from FIG. 2a that the other side edges (including the left and right edges and the lower edge) of the first antenna floor portion 210 are all adjacent to the rotating shaft 230.

The first antenna radiator 400 includes a first end 412 and a second end 414, and has a first antenna feed point 402 between the first end 412 and the second end 414, and a first antenna feed point 402 and a second antenna feed point 402 between the first end 412 and the second end 414. The first connection point 404 between the two ends 414. The portion of the first antenna radiator located between the first connection point 404 and the second end 414 is the first stub 406.

The first antenna feed point 402 is connected to the first antenna floor portion 210 through the first feed 440 and forms a ground point 442 of the first feed. The first antenna radiator 400 is connected to the first antenna floor portion 210 through the first grounding capacitor 420 at the first connection point 404, and forms a grounding point 422 of the first grounding capacitor. The first antenna feed point 402 and the ground point 442 of the first feed are located on one side of the center line O1 of the antenna floor 200. The first connection point 404 is closer to the center line O1 than the first antenna feed point 402, and the ground point 422 of the first grounding capacitor is closer to the center line O1 than the ground point 442 of the first feed.

Specifically, both ends of the first grounding capacitor 420 are connected to the first antenna radiator 400 and the first antenna floor portion 210 respectively. The first antenna radiator 400 can convert the alternating current in the metal body into an electromagnetic wave in the space or convert the electromagnetic wave in the space into an alternating current signal in the metal body, thereby transmitting or receiving an electromagnetic wave signal.

The first antenna feed point 402 and the ground point 442 of the first feed are located on one side of the center line O1 of the antenna floor 200. As shown in FIG. 2a, in this embodiment, the first antenna feed point 402 and the ground point 442 of the first feed are located on the left side of the center line O1. Those skilled in the art can understand that, in other alternative embodiments, the first antenna feed point 402 and the ground point 442 of the first feed source may also be located on the right side of the center line O1.

Further, the first connection point 404 where the first antenna radiator 400 is connected to the first grounding capacitor 420 is closer to the center line O1 than the first antenna feed point 402. In other words, the distance between the first connection point 404 and the center line O1 is smaller than the distance between the first antenna feeding point 402 and the center line O1. In this embodiment, the first connection point 404 is located on the left side of the center line O1. Those skilled in the art can understand that, in other alternative embodiments, the first connection point 404 may also be located on the right side of the center line O1.

The grounding point 422 of the first grounding capacitor formed by connecting the first grounding capacitor 420 to the first antenna floor portion 210 is closer to the center line O1 than the grounding point 442 of the first feed source. In other words, the distance between the ground point 422 of the first grounding capacitor and the center line O1 is smaller than the distance between the ground point 442 of the first feed source and the center line O1. In this embodiment, the ground point 422 of the first ground capacitor is located on the left side of the center line O1. Those skilled in the art can understand that, in other alternative embodiments, the grounding point 422 of the first grounding capacitor may also be located on the right side of the center line O1.

Furthermore, the part of the first antenna radiator located between the first connection point 404 and the second end 414 of the first antenna radiator 400 (that is, the right end in FIG. 2a) is the first stub 406, where the first The second end 414 of the antenna radiator 400 and the first antenna feed point 402 are respectively located on the first antenna radiator 400 on the opposite sides of the first connection point 404. In this embodiment, the end of the first branch 406 away from the first connection point 404 (that is, the right end of the first branch 406 in FIG. 2a, that is, the second end 414) extends to the right side of the rotating shaft 230. Those skilled in the art can understand that in other alternative embodiments, the end of the first branch 406 away from the first connection point 404 (ie, the right end in FIG. 2a, that is, the second end 414) may also only extend to The left side of the shaft 230.

As shown in FIG. 2a, the second antenna 500 includes a second antenna radiator 600 and a second grounding capacitor 620. A part of the second antenna radiator 600 is located outside the side edge of the second antenna floor portion 220 away from the rotating shaft 230 (ie, the lower side edge 222 in FIG. 2a). That is, a part of the second antenna radiator 600 is located outside the lower edge 222 of the second antenna floor portion 220 away from the rotating shaft 230, and the extending direction of the lower edge 222 is parallel to the axial direction O2 of the rotating shaft 230. Wherein, it can be seen from FIG. 2a that the other side edges (including the left and right edges and the upper edge) of the second antenna floor portion 220 are all adjacent to the rotating shaft 230.

The second antenna radiator 600 includes a first end 612 and a second end 614, and has a second antenna feed point 602 between the first end 612 and the second end 614, and a second antenna feed point 602 and a second antenna feed point 602 between the first end 612 and the second end 614. The second connection point 604 between the two ends 614. The portion of the second antenna radiator located between the second connection point 604 and the second end 614 is the second stub 606.

The second antenna feed point 602 is connected to the second antenna floor portion 220 through the second feed source 640, and forms the ground point 642 of the second feed source. The second antenna radiator 600 is connected to the second antenna floor portion 220 through the second grounding capacitor 620 at the second connection point 604, and forms a grounding point 622 of the second grounding capacitor. The second antenna feed point 602 and the ground point 642 of the second feed are located on the other side of the center line O1 opposite to one side. The second connection point 604 is closer to the center line O1 than the second antenna feed point 602, and the ground point 622 of the second grounding capacitor is closer to the center line O1 than the ground point 642 of the second feed.

Specifically, both ends of the second grounding capacitor 620 are connected to the second antenna radiator 600 and the second antenna floor portion 220 respectively. The second antenna radiator 600 can convert the alternating current in the metal body into a spatial electromagnetic wave or transform the spatial electromagnetic wave into an alternating current signal in the metal body, thereby transmitting or receiving electromagnetic wave signals.

The second antenna feed point 602 and the ground point 642 of the second feed are located on the other side of the center line O1 opposite to one side. As shown in FIG. 2a, in this embodiment, the second antenna feed point 602 and the ground point 642 of the second feed are located on the right side of the center line O1. Those skilled in the art can understand that, in other alternative embodiments, the second antenna feed point 602 and the ground point 642 of the second feed source may also be located on the left side of the center line O1. At this time, the first antenna The feed point 402 and the ground point 442 of the first feed are located on the right side of the center line O1.

The second connection point 604 where the second antenna radiator 600 is connected to the second grounding capacitor 620 is closer to the center line O1 than the second antenna feed point 602. In other words, the distance between the second connection point 604 and the center line O1 is smaller than the distance between the second antenna feed point 602 and the center line O1. In this embodiment, the second connection point 604 is located on the right side of the center line O1. Those skilled in the art can understand that, in other alternative embodiments, the second connection point 604 may also be located on the left side of the center line O1.

The grounding point 622 of the second grounding capacitor formed by connecting the second grounding capacitor 620 to the second antenna floor portion 220 is closer to the center line O1 than the grounding point 642 of the second feed source. That is, the distance between the ground point 622 of the second grounding capacitor and the center line O1 is smaller than the distance between the ground point 642 of the second feed source and the center line O1. In this embodiment, the grounding point 622 of the second grounding capacitor is located on the right side of the center line O1. Those skilled in the art can understand that, in other alternative embodiments, the ground point 622 of the second ground capacitor may also be located on the left side of the center line O1.

The part of the second antenna radiator 600 located between the second connection point 604 and one end of the second antenna radiator 600 is the second stub 606, wherein one end of the second antenna radiator 600 and the second antenna feed point 602 are at The second antenna radiators 600 are respectively located on opposite sides of the second connection point 604. In this embodiment, the end of the second branch 606 away from the first connection point 404 (that is, the left end of the second branch 606 in FIG. 2a, that is, the second end 614) extends to the right side of the rotating shaft 230. Those skilled in the art can understand that, in other alternative embodiments, the end of the first branch 406 away from the first connection point 404 (ie, the left end in FIG. 2a, that is, the second end 614) may also only extend to The left side of the shaft 230.

The first connection point 404, the first antenna feed point 402, the ground point 422 of the first grounding capacitor, and the ground point 442 of the first feed are located on one side of a virtual line, and the second connection point 604, the second antenna feed The point 602, the ground point 622 of the second grounding capacitor, and the ground point 642 of the second feed source are located on the other side of the virtual line; the virtual line is the center line O1 or is parallel to the center line O1. This can reduce the current intensity of the overlapping of the floor current formed by the first antenna radiator 400 on the first antenna floor portion 210 and the floor current formed by the second antenna radiator 600 on the second antenna floor portion 220 in the folded state, Therefore, it is avoided that the isolation and the envelope correlation coefficient between the first antenna radiator 400 and the second antenna radiator 600 deteriorate during use.

As shown in Figure 2b, when the antenna floor 200 is in a folded state, that is, when the first antenna floor portion 210 and the second antenna floor portion 220 are folded with each other, the distance between the first connection point 404 and the first antenna feed point 402 is smaller than that of the second antenna floor portion 402. The distance between the connection point 604 and the first antenna feed point 402, and the distance between the ground point 422 of the first grounding capacitor and the ground point 442 of the first feed is smaller than the distance between the ground point 622 of the second grounding capacitor and the first feed The distance to the location 442. At the same time, the distance between the second connection point 604 and the second antenna feed point 602 is less than the distance between the first connection point 404 and the second antenna feed point 602, and the ground point 622 of the second ground capacitor is away from the connection of the second feed source. The distance of the point 642 is smaller than the distance between the ground point 422 of the first grounding capacitor and the ground point 642 of the second feed source.

That is, when the antenna floor 200 is in a folded state, that is, when the first antenna floor portion 210 and the second antenna floor portion 220 are folded with each other, in a direction parallel to the axial direction O2 of the rotating shaft 230, the second connection point 604 is An antenna feed point 402 is located on both sides of the first connection point 404, and the ground point 622 of the second grounding capacitor and the ground point 442 of the first feed are located on both sides of the ground point 422 of the first grounding capacitor. At the same time, in a direction parallel to the axis direction O2 of the rotating shaft 230, the first connection point 404 and the second antenna feed point 602 are respectively located on both sides of the second connection point 604, and the ground point 422 of the first ground capacitor and the second The ground points 642 of the two feed sources are respectively located on both sides of the ground point 622 of the second grounding capacitor. That is, when the antenna floor 200 is in the folded state, in a direction parallel to the axial direction O2 of the rotating shaft 230, the first grounding capacitor 420 and the second grounding capacitor 620 are spaced apart and cannot cross.

Further, the first antenna radiator 400 also has a first preset point 416 between the first antenna feeding point 402 and the first connection point 404, and a distance between the first preset point 416 and the first connection point 404 The distance is less than or equal to 10mm. The second antenna radiator 600 also has a second preset point 616 between the second antenna feed point 602 and the second connection point 604, and the distance between the second preset point 616 and the second connection point 604 is less than or Equal to 10mm. When the first antenna floor part 210 and the second antenna floor part 220 are folded with each other, the second end 414 of the first antenna radiator 400 extends to no more than the second preset in a direction parallel to the axis direction O2 of the rotating shaft 230 At the position of the point 616, the second end 614 of the second antenna radiator 600 extends to a position not exceeding the first predetermined point 416.

With the above structure, it is possible to reduce the overlap between the floor current formed by the first antenna radiator 400 on the first antenna floor portion 210 and the floor current formed by the second antenna radiator 600 on the second antenna floor portion 220 in the folded state. In order to avoid the deterioration of the isolation and the envelope correlation coefficient between the first antenna radiator 400 and the second antenna radiator 600 during use.

Further, the distance between the first preset point 416 and the first connection point 404 is less than or equal to 2 mm. The distance between the second preset point 616 and the second connection point 604 is less than or equal to 2 mm. In this way, it is possible to further avoid deterioration of the isolation and envelope correlation coefficient between the first antenna radiator 400 and the second antenna radiator 600 during use.

That is, when the first antenna floor part 210 and the second antenna floor part 220 are folded with each other, they are located at the first preset point 416 and the first antenna radiator 400 in a direction parallel to the axial direction O2 of the rotating shaft 230. The first antenna radiator part between the second ends 414 and the second antenna radiator part located between the second preset point 616 and the second end 614 of the second antenna radiator 600 overlap or are separated from each other, and are located The portion of the first antenna radiator between the first preset point 416 and the first end 412 of the first antenna radiator 400 and the portion between the second preset point 616 and the first end 612 of the second antenna radiator 600 The second antenna radiator is partially separated.

In this embodiment, the frequency range of the working frequency band of the first antenna radiator 400 is 700-960 MHz, and the frequency range of the working frequency band of the second antenna radiator 600 is 700-960 MHz, that is, the working frequency band of the first antenna radiator 400 And the working frequency band of the second antenna radiator 600 is low frequency. The length of the first branch 406 is 10-30 mm, and the length of the second branch 606 is 10-30 mm. The capacitance value of the first grounding capacitor 420 is 1-5 pF, and the capacitance value of the second grounding capacitor is 1-5 pF. Those skilled in the art can understand that, in other alternative embodiments, the working frequency band of the first antenna radiator 400 and the working frequency band of the second antenna radiator 600 may also be medium and high frequency.

Further, in this embodiment, the working frequency band of the first antenna radiator 400 and the working frequency band of the second antenna radiator 600 are the same. Those skilled in the art can understand that, in other alternative embodiments, the working frequency band of the first antenna radiator 400 and the working frequency band of the second antenna radiator 600 may also partially overlap.

In this embodiment, the first grounding capacitor 420 and the second grounding capacitor 620 may be distributed capacitors or lumped capacitors.

In this embodiment, the first antenna radiator 400 and the second antenna radiator 600 are formed by the outer frame of the middle frame of the foldable electronic device. Those skilled in the art can understand that, in other alternative embodiments, the first antenna radiator 400 and the second antenna radiator 600 may also be formed of patterned metal foil or other metal structures.

As shown in FIGS. 2a-2b, the first antenna radiator 400 is also located near a pair of corners 214 of the first antenna floor portion 210 away from the rotation axis 230, and forms a line along the corner edge of the diagonal 214 of the first antenna floor portion 210. Bending like extension. In addition, the first antenna radiator 400 has a first straight line segment 408 and a second straight line segment 410. The first straight line segment 408 extends along the side edge of the first antenna floor portion 210 facing away from the rotating shaft 230. The first straight section 408 includes a first branch 406. The second straight line segment 410 is perpendicularly connected to an end of the first straight line segment 408 of the first antenna radiator 400 away from the first branch 406.

The second antenna radiator 600 is also located near a pair of corners 224 of the second antenna floor portion 220 away from the rotating shaft 230 and extends in a bent shape along the corner edge of the diagonal 224 of the second antenna floor portion 220. In addition, the second antenna radiator 600 also has a first straight line segment 608 and a second straight line segment 610. The first straight section 608 of the second antenna radiator 600 extends along the side edge of the second antenna floor portion 220 away from the rotating shaft 230. The first straight section 608 of the second antenna radiator 600 includes a second branch 606. The second straight section 610 of the second antenna radiator 600 is perpendicularly connected to an end of the first straight section 608 of the second antenna radiator 600 away from the second branch 606.

When the first antenna floor part 210 and the second antenna floor part 220 are spread out from each other, the diagonal 214 of the first antenna floor part 210 away from the rotating shaft 230 is opposite to the diagonal 224 of the second antenna floor part 220 away from the rotating shaft 230.

Those skilled in the art can understand that, in an alternative embodiment, the first antenna radiator 400 may also extend in a straight line along the side edge of the first antenna floor portion 210, and the second antenna radiator 600 may also It extends in a straight line along the side edge of the second antenna floor portion 220.

In the antenna system 100 of the present application, the pain points and difficulties of the existing foldable electronic device antenna design are overcome, and a pair of antennas can be made: when the antenna floor 200 is in the unfolded state, the first antenna radiator 400 and the second antenna The radiators 600 can work independently. When the antenna floor 200 is in a folded state, even when the first antenna radiator 400 and the second antenna radiator 600 are close to each other or even partially overlap (but do not touch), The first antenna radiator 400 and the second antenna radiator 600 have higher isolation and lower envelope correlation coefficient (ECC), which improves the radiation efficiency and diversity gain of the antenna, so that the first antenna radiator 400 and the second antenna radiator 600 still work normally, that is, the self-decoupling of the pair of antennas is realized.

As shown in FIG. 2a, in this embodiment, the first antenna radiator 400 and the second antenna radiator 600 are symmetrically arranged with respect to the center of the antenna floor 200. Those skilled in the art can understand that the first antenna radiator 400 and the second antenna radiator 600 may also be arranged asymmetrically.

The performance of the antenna system 100 will be specifically described below with reference to FIGS. 3a-8.

Please refer to FIGS. 3a and 3b. FIG. 3a shows the antenna system 100 according to an embodiment of the application when the antenna floor 200 is in an unfolded state and a folded state (that is, the antenna system 100 corresponding to the two states of FIGS. 2a and 2b) The measured S parameter performance simulation curve of the first antenna radiator 400 and the second antenna radiator 600 in the working frequency range, the frequency range of the working frequency of the first antenna radiator 400 and the second antenna radiator 600 is 824 -894MHz. FIG. 3b is the first antenna radiator 400 measured when the antenna system 100 according to an embodiment of the application is in an unfolded state and a folded state (that is, corresponding to the antenna system 100 in the two states of FIG. 2a and FIG. 2b) And the second antenna radiator 600 in the working frequency range of the ECC (Envelope Correlation Coefficient) parameter performance simulation graph, the first antenna radiator 400 and the second antenna radiator 600 in the working frequency range of 824- 894MHz.

Among them, in Figure 3a, the abscissa represents the frequency in GHz, and the ordinate represents the amplitude values of S11 and S12, in dB. S11 and S12 belong to one of the S parameters respectively. S11 represents the input reflection coefficient, that is, the input return loss. This parameter represents the transmission efficiency of the first antenna radiator 400 and the second antenna radiator 600. The larger the value, the first antenna radiator 400 and the second antenna The greater the energy reflected by the radiator 600 itself, the worse the efficiency of the antenna. S12 is the reverse transmission coefficient, that is, the isolation degree. The larger the amplitude value of S12, the higher the isolation degree, and the higher the radiation efficiency of the first antenna radiator 400 and the second antenna radiator 600.

"S1,1-folding" in FIG. 3a represents the input return loss (ie S11) of the first antenna radiator 400 and the second antenna radiator 600 measured when the antenna floor 200 is in the folded state; "S1,1- "Unfolded" means the input return loss of the first antenna radiator 400 and the second antenna radiator 600 measured when the antenna floor 200 is in the unfolded state (ie S11); "S1,2-folded" means that the antenna floor 200 is in the folded state The isolation between the first antenna radiator 400 and the second antenna radiator 600 measured at time (ie S12); “S1,2-expanded” means the first antenna radiator measured when the antenna floor 200 is in the expanded state The isolation between 400 and the second antenna radiator 600 (ie S12).

In Figure 3b, the abscissa represents the frequency in GHz, and the ordinate represents the amplitude value of the ECC (Envelope Correlation Coefficient). The smaller the envelope correlation coefficient, the higher the diversity gain of the antenna, the higher the signal-to-noise ratio and the higher the communication quality. "ECC-Expanded" refers to the envelope correlation coefficient of the first antenna radiator 400 and the second antenna radiator 600 when the antenna floor 200 of the antenna system 100 in FIG. 2a is in the expanded state. "ECC-folded" indicates the envelope correlation coefficient of the first antenna radiator 400 and the second antenna radiator 600 when the antenna floor 200 of the antenna system 100 in FIG. 2b is in a folded state.

The graphs shown in Figs. 3a and 3b are used to test the S parameters and ECC between the first antenna radiator 400 and the second antenna radiator 600 of the antenna system 100 shown in Figs. 2a and 2b through the three-dimensional electromagnetic field simulation software CST Acquired.

The simulation conditions for obtaining the graphs shown in Figure 3a and Figure 3b are shown in Table 1 below:

Table 1

Among them, because the second antenna 500 and the first antenna 300 are symmetrically arranged, and the first stub 406 of the first antenna 300 and the second stub 606 of the second antenna 500 overlap, only the first antenna 300 is shown in Table 1 above. The relevant parameter value.

It can be seen from Figure 3a that whether the antenna floor 200 is in the unfolded state or in the folded state, the isolation between the first antenna radiator 400 and the second antenna radiator 600 (ie S12) is in the frequency range of 824-894MHz (ie 0.824-0.894GHz) is still around 15dB, so when the antenna floor 200 is in the folded state, the isolation between the first antenna radiator 400 and the second antenna radiator 600 is not seriously deteriorated, and the first antenna radiates The body 400 and the second antenna radiator 600 can still work normally. Among them, when the antenna floor 200 is in the folded state, the resonance around 1 GHz comes from the clutter of the closed cover cavity.

It can be seen from Fig. 3b that when the antenna floor 200 is in the unfolded state, the envelope correlation coefficient (ie ECC) between the first antenna radiator 400 and the second antenna radiator 600 is in the frequency range of 824-894MHz (ie 0.824-0.894GHz) can be up to 0.1, when the antenna floor 200 is in the folded state, the envelope correlation coefficient (ie ECC) between the first antenna radiator 400 and the second antenna radiator 600 at the frequency of the working band The range of 824-894MHz (ie 0.824-0.894GHz) can still be below 0.2 without serious deterioration, and the first antenna radiator 400 and the second antenna radiator 600 can still work normally.

It should be noted that those skilled in the art can understand that the isolation between the first antenna radiator 400 and the second antenna radiator 600 is greater than 10 dB in the frequency range of the working frequency band, and the first antenna radiator 400 and the second antenna radiator 600 When the envelope correlation coefficient (ie ECC) of the antenna radiator 600 is lower than 0.5 in the frequency range of the working frequency band, the first antenna radiator 400 and the second antenna radiator 600 can work normally.

In order to illustrate the effect of the technical solution protected by this application, FIGS. 4a to 4c show schematic structural diagrams of three reference designs of the antenna system 100.

Figure 4a is a schematic structural diagram of the antenna system 100 of the first reference design, in which the first branch 406 (see Figure 2a) and the second branch 606 (see Figure 2a) are removed on the basis of the antenna system 100 of the present application (see Figure 2a). See Figure 2a). That is, in the first reference design, the first connection point 404 of the first antenna radiator 400 of the first antenna 300 is connected to the first antenna floor portion 210 of the antenna floor 200 through the first grounding capacitor 420, but the An antenna radiator 400 does not have a first stub 406 extending from the first connection point 404 (see FIG. 2a). The second connection point 604 of the second antenna radiator 600 of the second antenna 500 is connected to the second antenna floor portion 220 of the antenna floor 200 through the second grounding capacitor 620, but the second antenna radiator 600 does not have a second connection The second branch 606 extends from point 604 (see Figure 2a).

Fig. 4b is a schematic structural diagram of the antenna system 100 of the second reference design, in which the first grounding capacitor 420 (see Fig. 2a) and the second grounding capacitor 620 are removed on the basis of the antenna system 100 of the present application (see Fig. 2a) (Refer to Fig. 2a), so that the first antenna radiator 400 and the second antenna radiator 600 are directly connected to the antenna floor 200 through connecting ribs. That is to say, in the second reference design, the first antenna radiator 400 of the first antenna 300 has the first branch 406, but the first antenna radiator 400 is directly connected to the first antenna of the antenna floor 200 through the ribs. Floor section 210. The second antenna radiator 600 of the second antenna 500 has a second branch 606, but the second antenna radiator 600 is directly connected to the second antenna floor portion 220 of the antenna floor 200 through a rib.

Figure 4c is a schematic structural diagram of the antenna system 100 of the third reference design, in which the first branch 406 (see Figure 2a) and the second branch 606 (see Figure 2a) are removed on the basis of the antenna system 100 of the present application (see Figure 2a). See Figure 2a), and remove the first grounding capacitor 420 (see Figure 2a) and the second grounding capacitor 620 (see Figure 2a), so that the first antenna radiator 400 and the second antenna radiator 600 are directly connected to the antenna floor through the ribs 200. That is, in the third reference design, the first antenna radiator 400 of the first antenna 300 does not have the first stub 406 (see FIG. 2a), and the first antenna radiator 400 is directly connected to the antenna floor through the ribs. The first antenna floor portion 210 of 200. The second antenna radiator 600 of the second antenna does not have the second stub 606 (see FIG. 2a), and the second antenna radiator 600 is directly connected to the second antenna floor part 220 of the antenna floor 200 through the ribs.

Please refer to Figures 5a-5b. Figure 5a is this application (that is, corresponding to the antenna system 100 shown in Figures 2a and 2b) and three reference designs (that is, corresponding to the antenna system 100 shown in Figure 4a, Figure 4b, and Figure 4c, respectively) The S-parameter performance simulation curve of the first antenna radiator 400 and the second antenna radiator 600 in the working frequency range measured when the antenna floor 200 is in the folded state of the antenna system 100, the antenna systems of the present application and three reference designs The frequency range of the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 of 100 is 824-894 MHz.

Fig. 5b is the antenna system 100 of this application (that is, corresponding to the antenna system 100 of Fig. 2a and Fig. 2b) and three reference designs (that is, corresponding to the antenna system 100 shown in Fig. 4a, Fig. 4b, and Fig. 4c, respectively) on the antenna floor 200 The ECC (Envelope Correlation Coefficient) parameter performance simulation graph of the first antenna radiator 400 and the second antenna radiator 600 measured in the folded state in the working frequency range, the antenna system 100 of the present application and the three reference designs The frequency range of the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is 824-894 MHz. among them,

Among them, in Fig. 5a, the abscissa represents the frequency in GHz, and the ordinate represents the amplitude values of S11 and S12, and the unit is dB. S11 and S12 belong to one of the S parameters respectively. S11 represents the input reflection coefficient, that is, the input return loss. This parameter represents the transmission efficiency of the first antenna radiator 400 and the second antenna radiator 600. The larger the value, the first antenna radiator 400 and the second antenna The greater the energy reflected by the radiator 600 itself, the worse the efficiency of the antenna. S12 is the reverse transmission coefficient, that is, the isolation degree. The larger the amplitude value of S12, the higher the isolation degree, and the higher the radiation efficiency of the first antenna radiator 400 and the second antenna radiator 600.

"S1,1-this application" in FIG. 5a represents the input return loss (ie S11) of the first antenna radiator 400 and the second antenna radiator 600 measured by the antenna system 100 of the present application; "S1,1- Reference design 1" represents the input return loss (ie S11) of the first antenna radiator 400 and the second antenna radiator 600 measured by the antenna system 100 of the first reference design; "S1,1-reference design 2" represents The input return loss of the first antenna radiator 400 and the second antenna radiator 600 measured by the antenna system 100 of the second reference design (ie S11); "S1,1-reference design 3" represents the third reference design The input return loss of the first antenna radiator 400 and the second antenna radiator 600 measured by the antenna system 100 (ie S11).

"S1,2-this application" means the isolation between the first antenna radiator 400 and the second antenna radiator 600 measured by the antenna system 100 of this application (ie S12); "S1,2-reference design 1" Represents the isolation between the first antenna radiator 400 and the second antenna radiator 600 measured by the antenna system 100 of the first reference design (ie S12); "S1,2-reference design 2" represents the second reference The isolation between the first antenna radiator 400 and the second antenna radiator 600 measured by the designed antenna system 100 (ie S12); "S1,2-reference design 3" represents the antenna system 100 of the third reference design The measured isolation between the first antenna radiator 400 and the second antenna radiator 600 (ie S12).

In Fig. 5b, the abscissa represents frequency in GHz, and the ordinate represents the amplitude value of ECC (Envelope Correlation Coefficient). The smaller the envelope correlation coefficient, the higher the diversity gain of the antenna, the higher the signal-to-noise ratio and the higher the communication quality. "ECC-this application" means the envelope correlation coefficient of the first antenna radiator 400 and the second antenna radiator 600 in the antenna system 100 of this application. "ECC-Reference Design 1" represents the envelope correlation coefficient of the first antenna radiator 400 and the second antenna radiator 600 in the antenna system 100 of the first reference design. "ECC-Reference Design 2" represents the envelope correlation coefficient of the first antenna radiator 400 and the second antenna radiator 600 in the antenna system 100 of the second reference design. "ECC-Reference Design 3" represents the envelope correlation coefficient of the first antenna radiator 400 and the second antenna radiator 600 in the antenna system 100 of the third reference design.

The graphs shown in Figs. 5a and 5b are used to test the antenna system 100 of the present application shown in Figs. 2a and 2b and the antenna system 100 of the three reference designs shown in Figs. 4a-4c through the three-dimensional electromagnetic field simulation software CST. The S parameters and ECC between the first antenna radiator 400 and the second antenna radiator 600 when the antenna floor 200 is in the folded state are obtained.

The simulation conditions for obtaining the graphs shown in Figure 5a and Figure 5b are shown in Table 2 below:

Table 2

Among them, because the second antenna 500 and the first antenna 300 are symmetrically arranged, and the first stub 406 of the first antenna 300 and the second stub 606 of the second antenna 500 overlap, only the first antenna 300 is shown in Table 2 above. The relevant parameter value.

It can be seen from FIG. 5a that when the antenna floor 200 is in a folded state, the antenna system 100 proposed in the present application and three reference designs, the first antenna radiator 400 and the antenna system 100 in the antenna system 100 of the present application shown in FIG. 2a and FIG. 2b The isolation (ie, S12) between the second antenna radiators 600 is the highest, and the minimum value in the frequency range of 824-894 MHz of the working frequency band is still about 15 dB. However, the isolation between the first antenna radiator 400 and the second antenna radiator 600 of the three reference designs shown in FIGS. 4a to 4c is relatively low, which is the minimum value in the frequency range of 824-894MHz of the working frequency band. Only about 10dB. Among them, when the antenna floor 200 is in the folded state, the resonance around 1 GHz comes from the clutter of the closed cover cavity.

It can be seen from FIG. 5b that when the antenna floor 200 is in a folded state, the antenna system 100 proposed in this application and three reference designs, the first antenna radiator 400 and the antenna system 100 in the antenna system 100 of this application shown in FIGS. 2a and 2b The envelope correlation coefficient (ie, ECC) between the second antenna radiators 600 is the lowest, and can be less than 0.2 in the frequency range of 824-894 MHz of the working frequency band. However, the envelope correlation coefficient (ie ECC) between the first antenna radiator 400 and the second antenna radiator 600 of the three reference designs shown in Figs. 4a-4c is relatively high. Up to 0.4～0.5 in the range of 824-894MHz.

It can be seen from the above that, in the present application, the first antenna radiator 400 of the first antenna 300 is connected to the first antenna floor portion 210 through the first grounding capacitor 420 at an appropriate position, and the first branch 406 is provided. The appropriate position of the second antenna radiator 600 of the antenna 500 is connected to the second antenna floor part 220 through the second grounding capacitor 620, and the second branch 606 is provided so that the first antenna floor part 210 and the second antenna floor part 220 are mutually connected. When folded, even if the first antenna radiator 400 and the second antenna radiator 600 are close to each other or even partially overlap each other, the first antenna radiator 400 and the second antenna radiator 600 still have high isolation and relatively high isolation. The envelope correlation coefficient (ie, ECC) is low, so that the first antenna radiator 400 and the second antenna radiator 600 can still work normally when the antenna floor 200 is in a folded state. In other words, compared with the antenna system 100 of the three reference designs, the present application can greatly improve the isolation and envelope correlation coefficient (ie ECC) of the folded antenna pair.

Hereinafter, the working mechanism of the antenna system 100 of the present application will be described in detail by taking the first antenna 300 as an example with reference to FIGS. 6a-8. Those skilled in the art can understand that the same analysis method as the first antenna 300 can also be used for the second antenna 500.

FIG. 6a is a partial structural diagram of the antenna system 100 according to an embodiment of the application, in which only the first antenna 300 is reserved, and the antenna floor 200 is in an unfolded state. In other words, this figure removes the second antenna 500 on the basis of the antenna system 100 shown in FIG. 2a.

Fig. 6b is a partial structural diagram of the antenna system 100 of the first reference design, in which only the first antenna 300 is retained, and the antenna floor 200 is in an unfolded state. In other words, this figure removes the second antenna 500 on the basis of the antenna system 100 shown in FIG. 4a.

FIG. 6c is a partial structural diagram of the antenna system 100 of the second reference design, in which only the first antenna 300 is retained, and the antenna floor 200 is in an unfolded state. In other words, this figure removes the second antenna 500 on the basis of the antenna system 100 shown in FIG. 4b.

Figures 7a-7c are the first antenna radiator 400 of the antenna system 100 of the present application, the first reference design and the second reference design in Figures 6a-6c, respectively, on the antenna floor 200 at the same operating frequency Schematic diagram of current distribution. The working frequency of the first antenna radiator 400 is 870 MHz (that is, 0.87 GHz). These figures only show the current distribution of the first antenna radiator 400 on the first antenna floor part 210. The current distribution diagram is simulated by the three-dimensional electromagnetic field simulation software CST.

In Figs. 7a-7c, the direction indicated by the arrow indicates the direction of current flow there, and the thickness and length of the arrow indicate the magnitude of the current intensity. And the different gray scales in the figure represent different current intensities. It should be noted that the current distribution diagram simulated by the three-dimensional electromagnetic field simulation software CST is actually a color diagram, and different colors indicate different current intensities, which cannot be reflected in the current diagram, that is, the same gray in Figure 7a-Figure 7c The current intensities in different regions of the degree are not necessarily the same.

As shown in Figures 7a-7c, for the left half of the first antenna floor part 210, in the direction of the arrow, the current intensity gradually decreases, in the solid line frame (that is, near the upper left corner of the first antenna floor part 210) The current intensity inside is the largest, and the current intensity at the bottom of the first antenna floor part 210 is the smallest.

It can be seen from FIGS. 7a-7c that in the antenna system 100 of the first reference design and the second reference design, a relatively strong current flows into the dashed frame (that is, the upper right corner of the first antenna floor part 210), thus This results in lower isolation and higher envelope correlation coefficient (ECC) between the first antenna radiator 400 and the second antenna radiator 600 in the folded state. For the antenna solution proposed in this application, the current in the dashed frame (that is, the upper right corner of the first antenna floor portion 210) is relatively weak. Therefore, in the folded state, the first antenna radiator 400 and the second antenna radiator 600 have a relatively low current. High isolation and low envelope correlation coefficient (ECC).

In addition, in the antenna system 100 of the present application and the two reference designs, the current intensity in the solid line frame (that is, near the upper left corner of the first antenna floor portion 210) is the largest. Among them, in the antenna system 100 of the present application, the maximum value of the current is 39.43dB. In the antenna system 100 of the first reference design, the maximum current is 33.64dB. In the antenna system 100 of the second reference design, the maximum current is 34.69 dB.

In order to further explain the working mechanism of the present application, FIG. 8 shows a schematic diagram of the equivalent current distribution on the antenna floor of the first antenna radiator 400 of the antenna system 100 in FIG. 6a.

It can be seen from FIG. 8 that when the first antenna radiator 400 is working normally and the first feed source 440 feeds power, the current will flow along the first antenna radiator 400, and when it reaches the first connection point 404, it will be divided into two paths. It flows along the first grounding capacitor 420 to the antenna floor 200, and the other current continues to move to the right on the first branch 406 along the first antenna radiator 400. Wherein, the ground current passing through the first grounding capacitor 420 will flow to the left and right of the antenna floor 200, the floor current flowing to the left of the antenna floor 200 is represented by A11, and the floor current flowing to the right of the antenna floor 200 is represented by A12. The current moving to the right on the first branch 406 will also cause a current flowing to the left on the antenna floor 200 due to the electromagnetic field boundary conditions. The floor current flowing to the left is denoted by A2. When the floor current A12 and the floor current A2 are reversed at the same amplitude, little floor current will flow to the right, that is, there will be little current on the right side of the antenna floor 200, so that the first antenna radiator 400 and the second antenna radiator 400 can be folded in the folded state. The antenna radiators 600 have higher isolation and lower envelope correlation coefficient (ECC).

Those skilled in the art can understand that the working mechanism of the equivalent current distribution of the second antenna radiator 600 on the second antenna floor portion 220 is the same as the equivalent current distribution of the first antenna radiator 400 on the first antenna floor portion 210 The working mechanism is the same.

That is to say, in the present application, the current distribution of the first antenna radiator 400 on the first antenna floor portion 210 and the current distribution of the second antenna radiator 600 on the second antenna floor portion 220 may be specifically, see FIG. 2a, FIG. 2b and FIG. 8, the current of the first antenna radiator 400 passing through the first grounding capacitor 420 forms a first floor current A11 flowing in the first direction (that is, to the left in FIG. 8) in the first antenna floor portion 210 The first direction and the second direction are opposite to the second floor current A12 flowing in the second direction (that is, to the right in FIG. 8). The current flowing on the first branch 406 forms the third floor current A2, the second floor current A12 and the third floor current A2 flowing in the first direction (that is, to the left in FIG. 8) in the first antenna floor portion 210. The amplitudes are roughly equal. The current of the second antenna radiator 600 passing through the second grounding capacitor 620 forms a fourth floor current (not shown in the figure) and a fourth floor current (not shown in the figure) flowing in the first direction (that is, to the left in FIG. 8) in the second antenna floor portion 220. The fifth floor current (not shown in the figure) flowing in the second direction (that is, flowing toward the right in FIG. 8), and the current flowing on the second stub 606 is formed to flow toward the second direction in the second antenna floor portion 220 (that is, in FIG. The amplitude of the sixth floor current (not shown in the figure), the fourth floor current and the sixth floor current are approximately the same.

Please refer to FIG. 9. FIG. 9 is a schematic structural diagram of an antenna system 100 according to another embodiment of the application, in which the antenna floor 200 is in an unfolded state. As shown in FIG. 9, the structure of the antenna system 100 in this embodiment is basically the same as the structure of the antenna system 100 provided in the foregoing embodiment, except that the first antenna 300 further includes a first switch 700. 700 is connected between the first antenna radiator 400 and the first antenna floor part 210, and the first antenna radiator 400 is operated in different sub-frequency bands through the switching of the first switch 700.

In this embodiment, the part of the first antenna radiator 400 located between the first antenna feed point and the first end 412 of the first antenna radiator 400 is the first extension, and the first switch 700 is connected to the first extension. Section and the first antenna floor portion 210. Those skilled in the art can understand that, in other alternative implementation manners, the first switch 700 may also be arranged at other suitable positions of the first antenna radiator 400.

Further, the second antenna 500 further includes a second switch 800, which is connected between the second antenna radiator 600 and the second antenna floor portion 220, and the second antenna radiator 600 is switched by the second switch 800. Work in different sub-bands.

In this embodiment, the part of the second antenna radiator located between the second antenna feed point 602 and the first end 612 of the second antenna radiator 600 is the second extension, and the second switch 800 is connected to the second extension. Section and the second antenna floor section 220. Those skilled in the art can understand that, in other alternative embodiments, the second switch 800 may also be arranged at other suitable positions of the second antenna radiator 600.

Specifically, both the first switch 700 and the second switch 800 adopt single-pole multi-throw switches, so that the first switch 700 corresponds to multiple sub-bands in which the first antenna radiator 400 operates, and the second switch 800 corresponds to the second antenna radiator 600 to operate Multiple sub-bands. In this embodiment, both the first switch 700 and the second switch 800 adopt single-pole four-throw switches. Those skilled in the art can understand that, in other alternative embodiments, the first switch and the second switch may also adopt multi-pole multi-throw switches.

In this embodiment, a first capacitor 720 is provided on two of the paths connecting the first switch 700 and the first antenna radiator 400, and a first inductor 740 is provided on the other two paths. When the first inductance 740 is set tangentially in the first switch 700, the working frequency band of the first antenna radiator 400 moves to high frequency. When the first capacitor 720 is set tangentially in the first switch 700, the working frequency band of the first antenna radiator 400 moves to a low frequency.

Moreover, when the first switch 700 cuts to the first inductance 740 with different inductance values, the working frequency band of the first antenna radiator 400 will also move. When the first switch 700 cuts to the first capacitor 720 with different capacitance values, the working frequency band of the first antenna radiator 400 will also move.

It should be noted that during use, the position and quantity of the first inductor 740 and the first capacitor 720 can be set according to actual needs, and the first inductor 740 with a suitable inductance value and the first capacitor 720 with a suitable capacitance value can also be set. .

A second capacitor 820 is provided on two of the paths connecting the second switch 800 and the second antenna radiator 600, and a second inductor 840 is provided on the other two paths. When the second switch 800 is provided with the second inductor 840 tangentially, the working frequency band of the second antenna radiator 600 moves to high frequency. When the second capacitor 820 is arranged tangentially in the second switch 800, the working frequency band of the second antenna radiator 600 moves to a low frequency.

Moreover, when the second switch 800 cuts to the second inductor 840 with different inductance values, the operating frequency band of the second antenna radiator 600 will also move. When the second switch 800 cuts to the second capacitor 820 with different capacitance values, the working frequency band of the second antenna radiator 600 will also move.

It should be noted that during use, the position and quantity of the second inductor 840 and the second capacitor 820 can be set according to actual needs, and the second inductor 840 with a suitable inductance value and the second capacitor 820 with a suitable capacitance value can also be set. .

Further, the multiple sub-bands in which the first antenna radiator 400 works and the multiple sub-bands in which the second antenna radiator 600 works include a first sub-band, a second sub-band, a third sub-band, and a fourth sub-band. The frequency range of the first sub-band is 704-788MHz. The frequency range of the second sub-band is 791-860MHz. The frequency range of the third sub-band is 824-894MHz. The frequency range of the fourth sub-band is 880-960MHz.

In this embodiment, when the first switch 700 and the second switch 800 respectively tangent to one of the first capacitors 720 and one of the second capacitors 820, the operating frequency bands of the first antenna radiator 400 and the second antenna radiator 600 are Switch to the first sub-band. When the first switch 700 and the second switch 800 respectively tangent to the other first capacitor 720 and the other second capacitor 820, the operating frequency bands of the first antenna radiator 400 and the second antenna radiator 600 are switched to the second sub-band . When the first switch 700 and the second switch 800 are all turned off, the operating frequency band of the first antenna radiator 400 and the second antenna radiator 600 is switched to the third sub-band. When the first switch 700 and the second switch 800 respectively cut to the first inductor 740 and the second inductor 840, the operating frequency band of the first antenna radiator 400 and the second antenna radiator 600 is switched to the fourth sub-band. Those skilled in the art can understand that this is only an example, and the switching mode of the working frequency band is not limited to this.

As shown in FIG. 9, the first grounding capacitor 420 and the second grounding capacitor 620 are both adjustable capacitors. By adjusting the capacitance values of the first grounding capacitor 420 and the second grounding capacitor 620, the first antenna radiator 400 and the second grounding capacitor 620 are adjusted. The isolation and envelope correlation coefficient of the antenna radiator 600. When the antenna works in different frequency bands, in order to achieve the best isolation and envelope correlation coefficient (ECC), the first grounding capacitor 420 and the second grounding capacitor 620 also work at corresponding capacitance values.

The performance of the antenna system 100 provided in this embodiment will be described in detail below with reference to FIGS. 10a to 10b.

Fig. 10a is the three sub-systems of the first antenna radiator 400 and the second antenna radiator 600 measured when the antenna floor 200 is in the folded state of the antenna system 100 (the antenna system 100 shown in Fig. 9) of the present embodiment of the application. S-parameter performance simulation curve diagram of frequency band. Fig. 10b is the three sub-systems of the first antenna radiator 400 and the second antenna radiator 600 measured when the antenna floor 200 is in the folded state according to the antenna system 100 (the antenna system 100 shown in Fig. 9) of the present embodiment of the application. ECC (Envelope Correlation Coefficient) parameter performance simulation curve diagram of frequency band.

B28 in the figure represents the first sub-band, and the frequency range of the first sub-band is 704-788 MHz. B5 in the figure represents the third sub-band, and the frequency range of the third sub-band is 824-894 MHz. B8 in the figure represents the fourth sub-band, and the frequency range of the fourth sub-band is 880-960 MHz.

Those skilled in the art can understand that the frequency range of the second sub-band B20 is 791-860 MHz, which partially overlaps the frequency range of the third sub-band, and the remaining non-overlapping parts are also relatively close. When the first antenna radiator When the operating frequency bands of the 400 and the second antenna radiator 600 are switched to the second sub-band, the S-parameter curve and the ECC curve of the third sub-band are relatively close to the S-parameter curve and the ECC curve of the third sub-band.

In Figure 10a, the abscissa represents the frequency in GHz, and the ordinate represents the amplitude values of S11 and S12 in dB. S11 and S12 belong to one of the S parameters respectively. S11 represents the input reflection coefficient, that is, the input return loss. S12 is the reverse transmission coefficient, that is, isolation.

"S1,1-B5" in Figure 10a represents the input return loss measured when the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the third sub-band (ie S11); "S1,1 -B8" indicates the input return loss measured when the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the fourth sub-band (ie S11); "S1,1-B28" indicates the first antenna radiation The working frequency band of the body 400 and the second antenna radiator 600 is the input return loss measured when the first sub-frequency band (ie S11).

"S1,2-B5" means the isolation measured when the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the third sub-band (ie S12); "S1,2-B8" means the first The isolation measured when the working frequency band of the antenna radiator 400 and the second antenna radiator 600 is the fourth sub-band (ie S12); "S1,2-B28" represents the first antenna radiator 400 and the second antenna radiator The 600 working frequency band is the isolation measured in the first sub-frequency band (ie S12).

In Fig. 10b, the abscissa represents frequency in GHz, and the ordinate represents the amplitude value of ECC (Envelope Correlation Coefficient). The smaller the envelope correlation coefficient, the higher the diversity gain of the antenna, the higher the signal-to-noise ratio and the higher the communication quality. "ECC-B5" represents the envelope correlation coefficient measured when the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the third sub-band. "ECC-B8" represents the envelope correlation coefficient measured when the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the fourth sub-band. "ECC-B28" represents the envelope correlation coefficient measured when the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the first sub-band.

The graphs shown in FIGS. 10a and 10b are the sum of S parameters between the first antenna radiator 400 and the second antenna radiator 600 when the antenna system 100 shown in FIG. 9 is in the folded state tested by the three-dimensional electromagnetic field simulation software CST Obtained by ECC.

The simulation conditions for obtaining the graphs shown in FIG. 10a and FIG. 10b are shown in Table 3 below: B28 in the figure represents the first sub-band, and the frequency range of the first sub-band is 704-788 MHz. B5 in the figure represents the third sub-band, and the frequency range of the third sub-band is 824-894 MHz. B8 in the figure represents the fourth sub-band, and the frequency range of the fourth sub-band is 880-960 MHz.

table 3

Among them, because the second antenna 500 and the first antenna 300 are symmetrically arranged, and the first stub 406 of the first antenna 300 and the second stub 606 of the second antenna 500 overlap, only the first antenna 300 is shown in Table 3 above. The relevant parameter value.

It can be seen from Figure 10a that when the first antenna radiator 400 and the second antenna radiator 600 are switched to different operating frequency bands, the isolation between the first antenna radiator 400 and the second antenna radiator 600 will change to a certain extent. , But its minimum value is still around 15dB, so that the first antenna radiator 400 and the second antenna radiator 600 can still work normally when switched to different working frequency bands in the folded state. Among them, when the antenna floor 200 is in the folded state, the resonance near 1 GHz comes from the clutter of the closed cover cavity.

Specifically, when the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the first sub-band B28, the isolation between the first antenna radiator 400 and the second antenna radiator 600 is at the frequency of the working band The minimum value in the range 704-788MHz is still 16dB. When the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the third sub-band B5, the isolation between the first antenna radiator 400 and the second antenna radiator 600 is within the frequency range of the working frequency band 824- The minimum value in 894MHz is still at 14dB. When the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the fourth sub-band B8, the isolation between the first antenna radiator 400 and the second antenna radiator 600 is within the frequency range of the working frequency band 880- The minimum value in 960MHz is still 13dB.

It can be seen from Fig. 10b that when the first antenna radiator 400 and the second antenna radiator 600 are switched to different working frequency bands, within the working frequency range, the envelope between the first antenna radiator 400 and the second antenna radiator 600 The correlation coefficients (ie, ECC) are all lower than 0.4.

Specifically, when the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the first sub-band B28, the envelope correlation coefficient between the first antenna radiator 400 and the second antenna radiator 600 is working The frequency range of the frequency band is less than 0.2 within the frequency range of 704-788MHz. When the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the third sub-band B5, the envelope correlation coefficient between the first antenna radiator 400 and the second antenna radiator 600 is at the frequency of the working frequency band Less than 0.2 in the range of 824-894MHz. When the working frequency band of the first antenna radiator 400 and the second antenna radiator 600 is the fourth sub-band B8, the envelope correlation coefficient between the first antenna radiator 400 and the second antenna radiator 600 is at the frequency of the working frequency band It is less than 0.4 in the range of 880-960MHz.

In general, the foldable electronic device of the present application is connected to the first antenna floor part 210 through the first grounding capacitor 420 at an appropriate position of the first antenna radiator 400, and the first branch 406 is provided. The appropriate positions of the two antenna radiators 600 are connected to the second antenna floor portion 220 through the second grounding capacitor 620, and the second branch 606 is provided so that the antenna pair: the first antenna floor portion 210 and the second antenna floor portion 220 are mutually expanded When the first antenna radiator 400 and the second antenna radiator 600 work independently; when the first antenna floor portion 210 and the second antenna floor portion 220 are folded with each other, the first antenna radiator 400 and the second antenna radiator 600 When they are close to each other or even partially overlap (for example, when the first stub 406 and the second stub 606 partially overlap), the first antenna radiator 400 and the second antenna radiator 600 still have a high degree of isolation and Low envelope correlation coefficient (ie ECC), so that the first antenna radiator 400 and the second antenna radiator 600 can still work normally when the antenna floor 200 is in the folded state, that is, there are still two antennas in the folded state It works normally, with the same number of antennas as the unfolded state. In addition, it can work in different frequency bands by switching, so that each frequency band in the folded state has a performance similar to the unfolded state.

Obviously, those skilled in the art can make various changes and modifications to the application without departing from the spirit and scope of the application. In this way, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, this application is also intended to include these modifications and variations.

Claims

A foldable electronic device includes an antenna system, characterized in that the antenna system includes:

The antenna floor is divided into a first antenna floor part and a second antenna floor part that are mutually expanded or folded by a rotating shaft;

The first antenna includes a first antenna radiator and a first grounding capacitor, at least part of the first antenna radiator is located outside the edge of a side of the first antenna floor part away from the rotation axis, and the first antenna radiates The body includes a first end and a second end, and has a first antenna feed point between the first end and the second end, and a first antenna feed point between the first antenna feed point and the second end. The first connection point between the first connection point and the second end, the first antenna radiator part located between the first connection point and the second end is the first stub, and the first antenna feed point is connected to the The first antenna floor part forms a ground point of the first feed, and the first antenna radiator is connected to the first antenna floor part through the first ground capacitor at the first connection point , And form the ground point of the first grounding capacitor; the first antenna feed point and the ground point of the first feed source are located on one side of the center line of the antenna floor, and the first connection point is opposite to the The first antenna feed point is closer to the center line, and the ground point of the first grounding capacitor is closer to the center line relative to the ground point of the first feed; wherein, the center line is perpendicular to the center line. The axis direction of the shaft;

The second antenna includes a second antenna radiator and a second grounding capacitor, at least part of the second antenna radiator is located outside the edge of a side of the second antenna floor part away from the rotation axis, and the second antenna radiates The body includes a first end and a second end, and has a second antenna feed point between the first end and the second end, and a second antenna feed point between the second antenna feed point and the second end. The second connection point between the second connection point and the second end, the second antenna radiator part located between the second connection point and the second end is the second stub, and the second antenna feed point is connected to the all through the second feed source The second antenna floor part forms a ground point of the second feed source, and the second antenna radiator is connected to the second antenna floor part through the second grounding capacitor at the second connection point, And form the ground point of the second grounding capacitor; the second antenna feed point and the ground point of the second feed are located on the other side of the center line opposite to the one side, and the second connection The point is closer to the center line than the second antenna feed point, and the ground point of the second grounding capacitor is closer to the center line than the ground point of the second feed source.
The foldable electronic device according to claim 1, wherein the current of the first antenna radiator through the first grounding capacitor forms a first floor that flows in a first direction in the first antenna floor portion. The current and the second floor current flowing in the second direction, the first direction and the second direction are opposite; the current flowing on the first branch is formed on the first antenna floor part facing the first A third floor current flowing in a direction, the magnitude of the second floor current and the third floor current are approximately equal;

The current of the second antenna radiator through the second grounding capacitor forms a fourth floor current flowing in the first direction and a fifth floor current flowing in the second direction in the second antenna floor portion The current flowing on the second branch forms a sixth floor current flowing in the second direction on the second antenna floor portion, and the amplitude of the fourth floor current and the sixth floor current are substantially equal.
The foldable electronic device according to claim 1 or 2, wherein the first connection point, the first antenna feed point, the ground point of the first ground capacitor, and the first feed source The ground point is located on one side of a virtual line, and the second connection point, the second antenna feed point, the ground point of the second grounding capacitor, and the ground point of the second feed are located on the virtual line The other side of the line; wherein the virtual line is the center line or parallel to the center line.
The foldable electronic device according to any one of claims 1 to 3, wherein the first antenna radiator further has a gap between the first antenna feed point and the first connection point. The first preset point, the distance between the first preset point and the first connection point is less than or equal to 10 mm; the second antenna radiator also has a distance between the second antenna feed point and the A second preset point between the second connection points, where the distance between the second preset point and the second connection point is less than or equal to 10 mm;

When the first antenna floor part and the second antenna floor part are folded with each other, the second end of the first antenna radiator extends to no more than For the position of the second predetermined point, the second end of the second antenna radiator extends to a position that does not exceed the first predetermined point.
The foldable electronic device according to any one of claims 1 to 4, wherein the working frequency band of the first antenna radiator and the working frequency band of the second antenna radiator are the same or partially overlapped.
The foldable electronic device according to any one of claims 1-5, wherein the working frequency band of the first antenna radiator is 700-960MHz, and the working frequency band of the second antenna radiator is 700-960MHz. 960MHz; the length of the first branch is 10-30mm, the length of the second branch is 10-30mm; the capacitance value of the first grounding capacitor is 1-5pF, and the capacitance value of the second grounding capacitor is 1 -5pF.
7. The foldable electronic device according to any one of claims 1 to 6, wherein the first antenna radiator extends in a straight line along the side edge of the first antenna floor part;

The second antenna radiator extends in a straight line along the side edge of the second antenna floor portion.
The foldable electronic device according to any one of claims 1 to 6, wherein the first antenna radiator is also located near a pair of corners of the first antenna floor part away from the rotation axis, and is arranged along the The diagonal corner edge of the first antenna floor portion extends in a bent shape, and the first antenna radiator has a first straight line segment extending along the side edge of the first antenna floor portion, so The first straight line segment includes the first branch;

The second antenna radiator is also located near a pair of corners of the second antenna floor portion away from the rotation axis, and extends in a bent shape along the corner edge of the second antenna floor portion, and The second antenna radiator has a first straight section extending along the side edge of the second antenna floor portion, and the first straight section of the second antenna radiator includes the second branch;

When the first antenna floor portion and the second antenna floor portion are spread out from each other, the diagonal corner of the first antenna floor portion and the diagonal corner of the second antenna floor portion are disposed opposite to each other.
The foldable electronic device according to claim 8, wherein the first antenna radiator further comprises a second straight line segment, and the second straight line segment is perpendicularly connected to the first antenna radiator. One end of a straight line segment away from the first branch;

The second antenna radiator further includes a second straight line segment, and the second straight line segment of the second antenna radiator is perpendicularly connected to the first straight line segment of the second antenna radiator away from the second One end of the branch.
The foldable electronic device according to any one of claims 1-9, wherein the first grounding capacitance and the second grounding capacitance are both adjustable capacitors, and the first grounding capacitance and the second grounding capacitance are adjusted by adjusting the The capacitance value of the second grounding capacitor adjusts the isolation and envelope correlation coefficient between the first antenna radiator and the second antenna radiator.
The foldable electronic device according to claim 10, wherein the first antenna further comprises a first switch, and the first switch is connected between the first antenna radiator and the first antenna floor part. In between, the first antenna radiator is operated in different sub-frequency bands through the switching of the first switch;

The second antenna further includes a second switch connected between the second antenna radiator and the second antenna floor portion, and the second antenna is switched by the second switch. The radiator works in different sub-bands.
The foldable electronic device according to claim 11, wherein the first switch and the second switch are both single-pole multi-throw switches, so that the first switch corresponds to the operation of the first antenna radiator Multiple sub-bands, and the second switch corresponds to the multiple sub-bands in which the second antenna radiator works.
The foldable electronic device according to claim 12, wherein the plurality of sub-bands in which the first antenna radiator operates and the plurality of sub-bands in which the second antenna radiator operates both include a first sub-band Frequency band, second sub-band, third sub-band, and fourth sub-band;

The frequency range of the first sub-band is 704-788 MHz; the frequency range of the second sub-band is 791-860 MHz; the frequency range of the third sub-band is 824-894 MHz; and the frequency range of the fourth sub-band is 880-960 MHz.
The foldable electronic device according to any one of claims 11-13, wherein the first antenna located between the first antenna feed point and the first end of the first antenna radiator The antenna radiator part is a first extension section, and the first switch is connected between the first extension section and the first antenna floor section;

The portion of the second antenna radiator located between the second antenna feed point and the first end of the second antenna radiator is a second extension, and the second switch is connected to the second extension Section and the second antenna floor section.