CN117913510A

CN117913510A - Antenna assembly, middle frame assembly and electronic equipment

Info

Publication number: CN117913510A
Application number: CN202211237183.XA
Authority: CN
Inventors: 周林
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2022-10-10
Filing date: 2022-10-10
Publication date: 2024-04-19
Also published as: WO2024078168A1

Abstract

The application discloses an antenna assembly, a middle frame assembly and electronic equipment, and relates to the technical field of communication. In the application, the radiator is provided with a first free end, a second free end, a first feed point and a first grounding point, and the first feed source is used for exciting the radiator so as to support a first frequency band and a second frequency band; the first feed source is electrically connected with the first feed point through a first frequency selection circuit, the first frequency selection circuit is grounded, and current supporting the first frequency band is configured to flow through the first frequency selection circuit from the ground to be input into the radiator; the first ground point is grounded through the tuning circuit, and a current supporting the second frequency band is configured to flow from ground through the tuning circuit to be input to the radiator. According to the application, the feed-in of the first feed source is realized by utilizing one feed point, so that the antenna assembly realizes the wireless transmission function of two frequency bands through a single radiator, the number of radiators is effectively reduced, and the occupation of the antenna assembly to the space of the electronic equipment is further reduced.

Description

Antenna assembly, middle frame assembly and electronic equipment

Technical Field

The application relates to the technical field of communication, in particular to an antenna assembly, a middle frame assembly and electronic equipment.

Background

With more and more communication functions of electronic devices, a single antenna cannot meet the requirement of wireless communication of people. Therefore, many electronic devices are equipped with multiple antennas to receive different wireless signals, such as GSM, WIFI, etc. However, multiple antennas may occupy a larger area.

Disclosure of Invention

The application provides an antenna assembly, which comprises a radiator, a first antenna element and a second antenna element, wherein the radiator is provided with a first free end, a second free end, a first feed point and a first grounding point, the first grounding point is positioned between the first free end and the second free end, and the first feed point is positioned between the first free end and the first grounding point;

the first feed source is used for exciting the radiator to support a first frequency band and a second frequency band;

The first frequency selection circuit is electrically connected between the first feed point and the first feed source so that the first feed source is electrically connected with the first feed point through the first frequency selection circuit, the first frequency selection circuit is grounded, and current supporting the first frequency band is configured to flow through the first frequency selection circuit from the ground to be input into the radiator; and

And the tuning circuit is electrically connected between the first grounding point and the ground, so that the first grounding point is grounded through the tuning circuit, and the current supporting the second frequency band is configured to flow through the tuning circuit from the ground to be input into the radiator.

The present application provides an antenna assembly comprising:

A radiator having a first free end, a second free end, a first feed point, a second feed point, a first ground point, a second ground point, and a third ground point, the first ground point being located between the first free end and the second free end, the first feed point being located between the first free end and the first ground point, the second feed point being located between the first ground point and the second free end, the second ground point being located between the first ground point and the second feed point, the third ground point being located between the second feed point and the second free end;

a first feed for exciting a radiating portion of the radiator between the first feed point and the first free end to produce a first resonant mode and for exciting a radiating portion of the radiator between the first ground point and the first free end to produce a second resonant mode;

A first frequency selective circuit electrically connected between the first feed point and the first feed source such that the first feed source is electrically connected to the first feed point through the first frequency selective circuit, the first frequency selective circuit being grounded, the current of the first resonant mode being configured to flow from ground through the first frequency selective circuit, the first feed point to the first free end;

A tuning circuit electrically connected between the first ground point and ground such that the first ground point is grounded through the tuning circuit, the second resonant mode of current configured to flow from ground through the tuning circuit, the first ground point to the first free end;

a second feed for exciting a radiating portion of the radiator between the second ground point and the first free end to produce a third resonant mode and for exciting a radiating portion of the radiator between the second ground point and the second free end to produce a fourth resonant mode;

A second frequency selective circuit electrically connected between the second feed point and the second feed point such that the second feed point is electrically connected to the second feed point through the second frequency selective circuit, the second frequency selective circuit being grounded, the first frequency selective circuit being configured to be turned off when the second feed point excites the radiator and turned on when the first feed point excites the radiator, the second frequency selective circuit being configured to be turned off when the first feed point excites the radiator and turned on when the second feed point excites the radiator; and

The application provides a middle frame assembly, which comprises a third grounding point, a switching circuit, a second grounding point and a third grounding point, wherein the third grounding point is electrically connected between the third grounding point and the ground so as to enable the third grounding point to be grounded through the switching circuit, and the switching circuit is used for adjusting the frequency of a frequency band supported by a fourth resonance mode, and comprises the following components:

A substrate provided with a ground plane;

the frame is arranged around the substrate in a surrounding mode; and

The antenna assembly as described above, wherein the radiator is disposed on the frame and a gap is disposed between the radiator and the ground plane.

The present application provides an electronic device including:

A middle frame assembly comprising:

A substrate;

The frame is connected with the substrate, and comprises a first frame, a second frame, a third frame and a fourth frame which are connected end to end in sequence and are arranged around the substrate in a surrounding mode, wherein the first frame and the third frame are arranged oppositely, the second frame and the fourth frame are arranged oppositely, and the lengths of the first frame and the third frame are shorter than those of the second frame and shorter than those of the fourth frame;

The antenna assembly as described above, wherein the radiator is disposed on the first frame;

the battery cover is arranged on one side of the middle frame assembly, is respectively connected with the first frame, the second frame, the third frame and the fourth frame, and is arranged opposite to the substrate; and

The display screen is arranged on the other side of the middle frame assembly, is respectively connected with the first frame, the second frame, the third frame and the fourth frame, and is arranged opposite to the substrate.

By adopting the technical scheme of the application, the application has the following beneficial effects: according to the application, the feed-in of the first feed source is realized by utilizing one feed point, so that the antenna assembly realizes the wireless transmission function of two frequency bands through a single radiator, the number of radiators is effectively reduced, and the occupation of the antenna assembly to the space of the electronic equipment is further reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of an antenna assembly according to some embodiments of the present application;

Fig. 2 is a schematic structural diagram of the first feed and the first frequency selection circuit in the embodiment shown in fig. 1 in other embodiments;

FIG. 3 is a schematic diagram of the tuning circuit of the embodiment of FIG. 1 in alternate embodiments;

Fig. 4 is a schematic structural diagram of the antenna assembly shown in fig. 1 in another embodiment;

fig. 5 is a schematic structural diagram of the first feed and the first frequency selection circuit in the embodiment shown in fig. 4 in other embodiments;

fig. 6 is a schematic structural diagram of the second feed and the second frequency selection circuit in the embodiment shown in fig. 4, in other embodiments;

Fig. 7 is a schematic view of the antenna assembly of fig. 4 in alternative embodiments;

Fig. 8 is a schematic view of the antenna assembly of fig. 7 in alternative embodiments;

FIG. 9 is a schematic diagram of the switching circuit of FIG. 8 in some embodiments;

fig. 10 is a schematic diagram of a switching circuit in another embodiment of the antenna assembly according to the embodiment shown in fig. 9;

FIG. 11 is a graph of return loss of the antenna assembly of FIG. 1 excited by a first feed in another embodiment;

Fig. 12 is a graph of the overall efficiency of the system in which the antenna assembly of fig. 1 is excited by a first feed in another embodiment;

fig. 13 is a graph of return loss of the antenna assembly of fig. 7 excited by a second feed in another embodiment;

Fig. 14 is a graph of the overall efficiency of the system in which the antenna assembly of fig. 7 is excited by a second feed in another embodiment;

FIG. 15 is an exploded view of an electronic device according to an embodiment of the present application;

FIG. 16 is a schematic view of the frame assembly of the embodiment of FIG. 15;

fig. 17 is a schematic structural diagram of an electronic device according to an embodiment of the application.

Detailed Description

The present application will be described in further detail with reference to the drawings and embodiments. It is to be noted that the following embodiments are only for illustrating the present application, but do not limit the scope of the present application. Likewise, the following embodiments are only some, but not all, of the embodiments of the present application, and all other embodiments obtained by those skilled in the art without making any inventive effort are within the scope of the present application.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

The application provides an antenna assembly. The antenna assembly can be applied to electronic equipment. The antenna assembly may support at least one of a WiFi (Wireless-Fidelity) frequency band, a medium-high frequency band, an NR (new air interface) frequency band, or a low frequency band.

As used herein, "electronic equipment" (which may also be referred to as a "terminal" or "mobile terminal" or "electronic device") includes, but is not limited to, devices configured to receive/transmit communication signals via a wireline electrical connection (e.g., via a public-switched telephone network (PSTN), a Digital Subscriber Line (DSL), a digital cable, a direct cable electrical connection, and/or another data electrical connection/network) and/or via a wireless interface (e.g., for a cellular network, a Wireless Local Area Network (WLAN), a digital television network such as a DVB-H network, a satellite network, an AM-FM broadcast transmitter, and/or another communication terminal). A communication terminal configured to communicate through a wireless interface may be referred to as a "wireless communication terminal", "wireless terminal", or "mobile terminal". Examples of mobile terminals include, but are not limited to, satellites or cellular telephones; a Personal Communications System (PCS) terminal that may combine a cellular radiotelephone with data processing, facsimile and data communications capabilities; a PDA that can include a radiotelephone, pager, internet/intranet access, web browser, organizer, calendar, and/or a Global Positioning System (GPS) receiver; and conventional laptop and/or palmtop receivers or other electronic devices that include a radiotelephone transceiver. The mobile phone is the electronic equipment provided with the cellular communication module.

The antenna assembly may be one or more of a flexible circuit board (Flexible Printed Circuit, FPC) antenna, a Laser Direct Structuring (LDS) antenna, a Printed Direct Structuring (PDS) antenna, a metal bezel antenna (also known as a metal stub antenna). Of course, the antenna assembly may be other types of antennas, which will not be described in detail.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an antenna assembly according to some embodiments of the application. The antenna assembly 100 may include a radiator 10, a first feed 20 for exciting the radiator 10, a first frequency selection circuit 30 electrically connected between the radiator 10 and the first feed 20, and a tuning circuit 40 electrically connected between the first feed 20 and ground. The first feed 20 excites the radiator 10 to support a first frequency band and a second frequency band. The antenna assembly 100 can excite the radiator 10 through the first feed source 20, so that the wireless transmission function of two frequency bands, such as a first frequency band and a second frequency band, is realized, the number of the radiators 10 is effectively reduced, and the occupation of the antenna assembly 100 to the space of the electronic equipment is further reduced.

The terms "first," "second," "third," and the like in this disclosure are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first", "a second", "a third", etc. may include at least one such feature, either explicitly or implicitly.

The radiator 10 may be, but is not limited to being, an LDS radiator, or an FPC radiator, or a PDS radiator, or a metal stub radiator. In some embodiments, the radiator 10 may be a structural antenna (MECHANICAL DESIGN ANTENNA, MDA) radiator designed with the electronics' own insert metal.

The shape, structure and material of the radiator 10 are not particularly limited, and the shape of the radiator 10 includes, but is not limited to, a bent shape, a bar shape, a sheet shape, a rod shape, a coating, a film, etc. When the radiator 10 is in a strip shape, the extending track of the radiator 10 is not limited, so the radiator 10 can extend in a straight line, a curve, a multi-section bending track, and the like. The radiator 10 may be a line with a uniform width on the extending track, or may be a line with a gradual width change and a widening area with a different width.

In some embodiments, the total length of the radiator 10 may be 30-70mm. In some embodiments, the total length of the radiator 10 may be 50mm. It will be appreciated that the overall length of the radiator 10 can be adjusted as desired.

The radiator 10 may have a first free end 11, a second free end 12, a first feeding point 13 and a first ground point 14. The first feeding point 13 and the first grounding point 14 may be located between the first free end 11 and the second free end 12. The first feeding point 13 may be located between the first free end 11 and the first ground point 14, and on a side of the first ground point 14 away from the second free end 12. That is, the first ground point 14 may be located between the second free end 12 and the second feed point 15.

In some embodiments, the two ends of the radiator 10, such as the first free end 11 and the second free end 12, may each have a gap between the other components. In some scenarios, when the antenna assembly 100 is applied in an electronic device, the first free end 11 and the second free end 12 of the radiator 10 may not be easily held or blocked at the same time with gaps (i.e., two gaps) respectively between other components in the electronic device. Even if one of the two slots is blocked, the radiator 10 can transmit and receive electromagnetic wave signals, so that the antenna assembly 100 can have better communication performance when applied to electronic equipment.

Referring to fig. 1, the radiator 10 may have a linear shape. The first free end 11 and the second free end 12 may be opposite ends of the radiator 10. In other embodiments, the radiator 10 may be bent. The first free end 11 and the second free end 12 may not be opposed in a straight direction. The first free end 11 and the second free end 12 may be both ends of the radiator 10. In some embodiments, the distance between the first free end 11 and the second free end 12 on the extended trajectory of the radiator 10 may be the total length of the radiator 10.

Referring to fig. 1, the first feed 20 may be indirectly connected to the first feeding point 13 through a first frequency selection circuit 30. The first feed 20 may excite the radiator 10 to support a first frequency band and a second frequency band.

In some embodiments, the first frequency band may be a medium-high frequency band or a low frequency band.

In some embodiments, the first frequency band may be a WiFi frequency band or an NR frequency band.

In some embodiments, the first frequency band may be a WiFi frequency band. In some embodiments, the first frequency band may be a WiFi5G frequency band.

In some embodiments, the first feed 20 may excite a radiating portion of the radiator 10 located between the first free end 11 and the first feed point 13 to produce a first resonant mode supporting the first frequency band.

In some embodiments, the first resonant mode is an inverted F Antenna (IFA, inverted-F Antenna) mode. In some embodiments, the first resonant mode is an IFA antenna mode of 1/4 wavelength.

In some embodiments, the current of the first resonant mode comprises a current I1 flowing from the first feed point 13 to the first free end 11.

In some embodiments, the second frequency band may be a medium-high frequency band or a low frequency band.

In some embodiments, the second frequency band may be a WiFi frequency band or an NR frequency band.

In some embodiments, the second frequency band may be an NR high frequency band. In some embodiments, the second frequency band may be the N78 frequency band (3.4 GHz-3.6 GHz).

In some embodiments, the first feed 20 may excite a radiating portion of the radiator 10 located between the first free end 11 and the first ground point 14 to produce a second resonant mode supporting the second frequency band.

In some embodiments, the second resonant mode may be a left-hand antenna mode (a mode of a composite left-hand transmission line structure). In some embodiments, the second resonant mode may be a 1/4 wavelength left-hand antenna mode.

In some embodiments, the current of the second resonant mode comprises a current I2 flowing from the first ground point 14 to the first free end 11.

Referring to fig. 1, the first frequency selection circuit 30 is electrically connected between the first feeding point 13 and the first feed source 20. That is, the first feed 20 may be electrically connected to the first feed point 13 through the first frequency selection circuit 30. The first frequency selection circuit 30 may be directly grounded, so that the current I1 supporting the first frequency band may flow through the first frequency selection circuit 30 from ground to be input to the radiator 10.

In some embodiments, the first frequency selection circuit 30 may be comprised of a switch control circuit and/or a load circuit, or may be comprised of an adjustable capacitance (which may also be replaced by a fixed value capacitance) and/or an adjustable inductor. In an embodiment, the switch control circuit may be a switch chip with a switch function, or may be a single pole multiple throw switch or a single pole single throw switch.

Referring to fig. 2, fig. 2 is a schematic diagram illustrating a configuration of the first feed 20 and the first frequency selection circuit 30 in the embodiment shown in fig. 1. The first frequency selection circuit 30 may include a first matching circuit 31. The first matching circuit 31 has one end connected to the first feed 20, the other end connected directly or indirectly to the first feed point 13, and the other end grounded.

In some embodiments, the first matching circuit 31 may include a second capacitor C2 with one end grounded and a first capacitor C1 with one end electrically connected to the other end of the second capacitor C2. The other end of the first capacitor C1 is electrically connected to the first feeding point 13. The other end of the second capacitance C2 may also be electrically connected to the first feed 20.

In some embodiments, the second capacitor C2 and the first capacitor C1 can flow the current I1 when the radiator 10 supports the first frequency band. Specifically, the current I1 may flow from ground through the second capacitor C2, the first capacitor C1, and to the first feeding point 13. The second capacitor C2 can be a virtual ground point.

In some embodiments, the capacitance of the second capacitor C2 may be 1pF.

Referring to fig. 1, the tuning circuit 40 may be used to adjust the frequency of the second frequency band. The tuning circuit 40 is electrically connected between the first ground point 14 and ground. That is, the first ground point 14 may be grounded through the tuning circuit 40. In some embodiments, the current I2 supporting the second frequency band may flow through the tuning circuit 40 from ground to input the radiator 10.

In some embodiments, tuning circuit 40 may be comprised of a switch control circuit and/or a load circuit, or may be comprised of an adjustable capacitance (which may also be replaced by a fixed value capacitance) and/or an adjustable inductor. In an embodiment, the switch control circuit may be a switch chip with a switch function, or may be a single pole multiple throw switch or a single pole single throw switch.

Referring to fig. 3, fig. 3 is a schematic diagram illustrating the configuration of the tuning circuit 40 according to the embodiment shown in fig. 1 in other embodiments. Tuning circuit 40 may include a third capacitance C3 electrically connected between first ground point 14 and ground. The first ground point 14 may be grounded through a third capacitor C3.

In some embodiments, the third capacitor C3 may circulate the current I2 when the radiator 10 supports the second frequency band. Specifically, the current I2 may flow from ground through the third capacitor C3 and to the first ground 14. The third capacitor C3 can be a virtual ground point.

In some embodiments, the capacitance of the third capacitor C3 is 2.7pF.

In some embodiments, the tuning circuit 40, e.g., the third capacitor C3, is arranged such that the second resonant mode is a left-hand antenna mode employing a capacitively coupled feed to form a composite left-hand transmission line structure.

Referring to fig. 4, fig. 4 is a schematic structural diagram of the antenna assembly 100 shown in fig. 1 in another embodiment. The radiator 10 may also have a second feed point 15 located between the second free end 12 and the first ground point 14. Accordingly, the antenna assembly 100 may also include a second feed 50. The second feed 50 may be directly or indirectly electrically connected to the second feed point 15. The second feed 50 may excite the radiator 10.

Referring to fig. 4, in the antenna assembly 100, a circuit, such as the first frequency selection circuit 30, for example, in which the first feed 20 is electrically connected to the first feeding point 13 may be set to a high impedance state when the second feed 50 excites the radiator 10, and to a low impedance state when the first feed 20 excites the radiator 10. Further, the antenna assembly 100 may promote isolation of the first feed 20 from the second feed 50 when the second feed 50 excites the radiator 10.

In some embodiments, in the antenna assembly 100, a circuit, such as the first frequency selective circuit 30, that electrically connects the first feed 20 to the first feed point 13 may be configured to be turned off when the second feed 50 excites the radiator 10 and turned on when the first feed 20 excites the radiator 10.

Referring to fig. 5, fig. 5 is a schematic diagram illustrating a configuration of the first feed 20 and the first frequency selection circuit 30 in the embodiment shown in fig. 4. The first frequency selection circuit 30 may also include a first filter circuit 32. The first filter circuit 32 is electrically connected between the first feeding point 13 and the first matching circuit 31, e.g. the first capacitor C1. I.e. the first feed point 13 is electrically connected to the first matching circuit 31, e.g. the first capacitor C1, via the first filter circuit 32.

In some embodiments, the first filter circuit 32 may control the first frequency selective circuit 30 to be in a low impedance state when the first feed 20 excites the radiator 10 and to be in a high impedance state when the second feed 50 excites the radiator 10. In some embodiments, the first filter circuit 32 may control the first frequency selective circuit 30 to be in a short circuit state when the first feed 20 excites the radiator 10 and to be in an open circuit state when the second feed 50 excites the radiator 10. In some embodiments, the first filter circuit 32 may control the first frequency selective circuit 30 to be on when the first feed 20 excites the radiator 10 and off when the second feed 50 excites the radiator 10.

Referring to fig. 5, the first filter circuit 32 may include a fourth capacitor C4 electrically connected between the first feeding point 13 and the first matching circuit 31, for example, the first capacitor C1, and a first inductor L1 electrically connected between the first feeding point 13 and the first matching circuit 31, for example, the first capacitor C1. That is, the first feeding point 13 may be electrically connected to the first matching circuit 31, for example, the first capacitor C1, through the fourth capacitor C4 and the first inductor L1, respectively.

In some embodiments, one end of the fourth capacitor C4 and the first inductor L1, which are electrically connected to the first matching circuit 31, are electrically connected to one end of the first capacitor C1. The fourth capacitor C4 and the first inductor L1 are in parallel resonance to form a low-resistance high-pass filter circuit. That is, the first filter circuit 32 may be a low-resistance high-pass filter circuit, improving isolation between the first feed 20 and the second feed 50.

In some embodiments, the fourth capacitor C4 may circulate the current I1 when the radiator 10 supports the first frequency band. Specifically, the current I1 may flow through the first matching circuit 31 (e.g., the second capacitor C2, the first capacitor C1), the fourth capacitor C4 and to the first feeding point 13.

Referring to fig. 4, in the antenna assembly 100, a circuit in which the second feed 50 is electrically connected to the second feeding point 15 may be set to be in a high impedance state when the first feed 20 excites the radiator 10 and in a low impedance state when the second feed 50 excites the radiator 10. Further, the antenna assembly 100 may improve the isolation of the first feed 20 from the second feed 50 when the first feed 20 excites the radiator 10.

In some embodiments, in the antenna assembly 100, the circuitry electrically connecting the second feed 50 to the second feed point 15 may be arranged to be in an open state when the first feed 20 excites the radiator 10 and in a short state when the second feed 50 excites the radiator 10.

In some embodiments, in the antenna assembly 100, circuitry that electrically connects the second feed 50 to the second feed point 15 may be configured to open when the first feed 20 excites the radiator 10 and to communicate when the second feed 50 excites the radiator 10.

Referring to fig. 4, the antenna assembly 100 may further include a second frequency selection circuit 60 electrically connected between the second feed 50 and the second feed point 15. The second feed 50 may be electrically connected to the second feed point 15 through a second frequency selective circuit 60. That is, the second frequency selection circuit 60 may serve as a circuit that electrically connects the second feed 50 to the second feed point 15. Further, the second frequency selection circuit 60 is arranged to be in a high impedance state when the first feed 20 excites the radiator 10 and in a low impedance state when the second feed 50 excites the radiator 10. In some embodiments, the second frequency selective circuit 60 is arranged to be in an open circuit state when the first feed 20 excites the radiator 10 and to be in a short circuit state when the second feed 50 excites the radiator 10. In some embodiments, the second frequency selective circuit 60 is configured to be turned off when the first feed 20 excites the radiator 10 and to be turned on when the second feed 50 excites the radiator 10.

In some embodiments, the second frequency selection circuit 60 may be comprised of a switch control circuit and/or a load circuit, or may be comprised of an adjustable capacitance (which may also be replaced by a fixed value capacitance) and/or an adjustable inductor. In an embodiment, the switch control circuit may be a switch chip with a switch function, or may be a single pole multiple throw switch or a single pole single throw switch.

Referring to fig. 6, fig. 6 is a schematic diagram illustrating a configuration of the second feed 50 and the second frequency selection circuit 60 in the embodiment shown in fig. 4. The second frequency selection circuit 60 may have a first end 61 and a second end 62. The first end 61 may be electrically connected to the second feed 50 and the second end 62 may be electrically connected to the second feed point 15.

The second frequency selection circuit 60 may include a second matching circuit 63 and a second filtering circuit 64. One end of the second matching circuit 63 is electrically connected to one end of the second filter circuit 64 to form a first end 61 and a second end 62. That is, the second matching circuit 63 and the second filtering circuit 64 may be electrically connected between the second feeding point 15 and the ground, and the second feed 50 may be directly electrically connected with the second feeding point 15, so that the second feeding point 15 may be grounded through the second matching circuit 63 and the second filtering circuit 64, respectively.

In some embodiments, the second matching circuit 63 may include a second inductance L2 electrically connected between the second terminal 62 and ground. The second terminal 62 is grounded through a second inductor L2.

In some embodiments, the second filter circuit 64 may control the second frequency selective circuit 60 to be in a high impedance state when the first feed 20 excites the radiator 10 and to be in a low impedance state when the second feed 50 excites the radiator 10.

In some embodiments, the second filter circuit 64 may control the second frequency selective circuit 60 to be in an open state when the first feed 20 excites the radiator 10 and to be in a short state when the second feed 50 excites the radiator 10.

In some embodiments, the second filter circuit 64 may control the second frequency selective circuit 60 to be off when the first feed 20 excites the radiator 10 and to be on when the second feed 50 excites the radiator 10.

In some embodiments, the second filter circuit 64 may include a third inductor L3 and a fifth capacitor C5 electrically connected between the second terminal 62 and ground. The third inductance L3 is connected in series with the fifth capacitance C5. The second end 62 is grounded through the third inductor L3 and the fifth capacitor C5 in sequence. The third inductor L3 and the fifth capacitor C5 may form a low-pass high-resistance filter circuit. That is, the second filter circuit 64 may be a low-pass, high-resistance filter circuit that increases the isolation between the first feed 20 and the second feed 50.

In some embodiments, the capacitance of the fifth capacitor C5 is 2.7pF.

The second feed 50 may excite the radiator 10 to produce a resonant mode that supports multiple frequency bands (e.g., part or all of at least one of a mid-high frequency band, a low frequency band). Referring to fig. 7, fig. 7 is a schematic diagram illustrating an antenna assembly 100 shown in fig. 4 in other embodiments. The radiator 10 may also have a second ground point 16 located between the first ground point 14 and the second feed point 15. The second ground point 16 is grounded.

In some embodiments, the second feed 50 may excite a radiating portion of the radiator 10 located between the first free end 11 and the second ground point 16 to produce a third resonant mode supporting a third frequency band.

In some embodiments, the third frequency band may be a long term evolution (Long Term Evolution, LTE) enabled frequency band. In some embodiments, the third frequency band may be an LTE low frequency band. In some embodiments, the third frequency band may be the LTE B20 frequency band (791 MHz-861 MHz).

In some embodiments, the third resonant mode may be an IFA antenna mode. The current I3 of the third resonance mode may flow from the second ground point 16 to the first free end 11.

In some embodiments, the second feed 50 may excite a radiating portion of the radiator 10 located between the second ground point 16 and the second free end 12 to produce a fourth resonant mode supporting a fourth frequency band.

In some embodiments, the fourth frequency band may be a medium-high frequency band (1710 MHz-2690 MHz). In some embodiments, the fourth frequency band may be a high frequency band in LTE. In some embodiments, the fourth frequency band may be at least one of an LTE B3 frequency band, an LTE B1 frequency band, an LTE B39 frequency band, an LTE B40 frequency band, or an LTE B41 frequency band.

In some embodiments, the fourth resonant mode is an IFA antenna mode.

In some embodiments, the current of the fourth resonant mode may include a current I4 flowing from the second ground point 16 to the second free end 12.

Referring to fig. 8, fig. 8 is a schematic diagram illustrating an antenna assembly 100 shown in fig. 7 in other embodiments. The radiator 10 is provided with a third ground point 17 between the second free end 12 and the second feed point 15.

The antenna assembly 100 may also include a switching circuit 70 electrically connected between the third ground point 17 and ground. The third ground point 17 is grounded through the switching circuit 70. The switching circuit 70 may adjust the frequency of the fourth frequency band.

The switching circuit 70 may switch between the plurality of sub-bands in the fourth band. For example, the switching circuit 70 may switch between LTE B3 band, LTE B1 band, LTE B39 band, LTE B40 band, and LTE B41 band in the fourth band.

The switching circuit 70 may be comprised of a switch control circuit and/or a load circuit, or may be comprised of an adjustable capacitance (which may also be replaced by a fixed capacitance) and/or an adjustable inductor. In an embodiment, the switch control circuit may be a switch chip with a switch function, or may be a single pole multiple throw switch or a single pole single throw switch.

Referring to fig. 9, fig. 9 is a schematic diagram illustrating a configuration of the switching circuit 70 shown in fig. 8 according to some embodiments. The switching circuit 70 may comprise a switch 71 and at least one frequency selective branch 72.

The changeover switch 71 has a common terminal 711 electrically connected to the third ground point 17, a plurality of connection terminals 712, and a changeover portion 713. The switching part 713 may be electrically connected to the common terminal 711. The switching portion 713 may be electrically connected to one connection 712 under control of a control signal (which may be from an electronic device such as a processor or from other electronic devices).

One end of each frequency selective branch 72 is electrically connected to a connecting end 712 in a one-to-one correspondence, and the other end is grounded.

Referring to fig. 9, the switching portion 713 may be selectively electrically connected to different connection ends 712, so that one end of each of the frequency selective branches 72 is electrically connected to the second feeding point 15, and the other end is grounded, so that the radiating portion of the radiator 10 between the second grounding point 16 and the second free end 12 has different effective electrical lengths in different states.

It should be understood that the illustrated number of frequency selective branches 72 in the drawings should not be construed as limiting the number of frequency selective branches 72 provided by embodiments of the present application.

In some embodiments, each frequency selective branch 72 may include a capacitance, or an inductance, or a combination of capacitance and inductance.

In an embodiment, when frequency selective branches 72 are plural, each frequency selective branch 72 may be different such that the degree of adjustment to the electrical length of radiator 10 is different when different frequency selective branches 72 are electrically connected to radiator 10. Further, the frequency selection is switched between a plurality of sub-bands in the fourth band, for example, LTE B3 band, LTE B1 band, LTE B39 band, LTE B40 band, LTE B41 band, and the like.

It should be noted that, the frequency selective branches 72 are different, and the devices included in each frequency selective branch 72 may be different; or the included devices are the same, but the connection relation between the devices is different; or the devices included are identical and the connection relationship is identical, but the parameters (such as capacitance, or inductance) of the devices are different.

In addition, since the radiator 10 supports more sub-bands in the fourth frequency band, the number of frequency selective branches 72 is generally greater than or equal to two in order to achieve better adjustment of the LB frequency band.

It should be understood that the number of the switches 71 in fig. 9 may be plural, and each frequency selecting branch 72 is electrically connected to one switch 71. Referring to fig. 10, fig. 10 is a schematic diagram of a structure of the switching circuit 70 in another embodiment of the antenna assembly 100 in the embodiment shown in fig. 9. Each frequency selective branch 72 is electrically connected to one of the switches 71 in a one-to-one correspondence.

In addition, in fig. 9, the grounded end of the switch 71 may be electrically connected to the third ground point 17, and the corresponding end electrically connected to the third ground point 17 may be directly grounded.

In some embodiments, the frequency selective branch 72 may include a first frequency selective branch 721, a second frequency selective branch 722, a third frequency selective branch 723, and a fourth frequency selective branch 724. Wherein, one end of each of the first frequency-selecting branch 721, the second frequency-selecting branch 722, the third frequency-selecting branch 723 and the fourth frequency-selecting branch 724 is electrically connected with one connecting end 712, and the other end is grounded.

In some embodiments, the first frequency selective branch 721 may be a capacitor. In some embodiments, the second frequency selective branch 722, the third frequency selective branch 723, and the fourth frequency selective branch 724 may each be an inductance.

In an embodiment, referring to fig. 9 and 10, taking the LTE B3 band, the LTE B1 band, the LTE B39 band, the LTE B40 band, and the LTE B41 band as examples, when the frequency is selected by the first frequency selecting branch 721, the second frequency selecting branch 722, the third frequency selecting branch 723, and the fourth frequency selecting branch 724, the following table is shown:

Referring to fig. 8, a first resonant mode corresponding to the current I1 can operate in the WiFi5G band. The second resonant mode corresponding to current I2 is operable in the N78 band (3.4 GHz-3.6 GHz). The third resonant mode, corresponding to current I3, may operate in the LTE B20 band (791 MHz-861 MHz). The fourth resonant mode corresponding to the current I4 may operate in a high frequency band in LTE such as LTE B3 band, LTE B1 band, LTE B39 band, LTE B40 band, LTE B41 band. Further, the antenna assembly 100 may implement an ENDC (dual connectivity (E-UTRAN new radio-Dual Connectivity, abbreviated as ENDC) combination of the N78 band and the WiFi5G band, or an ENDC of the LTE B20 band and the middle-high frequency band (e.g., one of the LTE middle-high frequency bands such as the LTE B3 band, the LTE B1 band, the LTE B39 band, the LTE B40 band, the LTE B41 band, etc.).

Because the current path of the current I4 is not overlapped with the current path of the current I1 and the current path of the current I2, the high-isolation performance exists between the middle-high frequency band and the N78 frequency band, and the high-isolation performance exists between the middle-high frequency band and the WiFi5G frequency band.

Referring to fig. 11, fig. 11 is a graph of return loss of the antenna assembly 100 of fig. 1 excited by the first feed 20 in another embodiment, with frequency (GHz) on the horizontal axis and return loss (dB) on the vertical axis. Curve a is the return loss curve of the antenna assembly 100 under the first feed 20. With A1 (3.4959, -4.9113), A2 (5.4985, -11.065), A3 (4.8473, -3.7118) on curve A. It can be seen that the antenna assembly 100 has good antenna performance in the first frequency band (e.g. WiFi5G frequency band) and the second frequency band (e.g. N78 frequency band), so that the working state is good, and the engineering requirements can be satisfied.

Referring to fig. 12, fig. 12 is a graph of the overall system efficiency (System Total Efficiency) of the antenna assembly 100 of fig. 1 excited by the first feed 20 in another embodiment. The horizontal axis is frequency (GHz) and the vertical axis is system total efficiency (dB). Curve B is the overall efficiency curve of the system for the antenna assembly 100 under the first feed 20. Wherein there are B1 (3.339, -3.7824), B2 (5.3513, -3.8836), B3 (5.6551, -3.8342) on curve B. It can be seen that the antenna assembly 100 has good antenna performance in the first frequency band (e.g. WiFi5G frequency band) and the second frequency band (e.g. N78 frequency band), so that the working state is good, and the engineering requirements can be satisfied.

Referring to fig. 13, fig. 13 is a graph of return loss of the antenna assembly 100 of fig. 7 excited by the second feed 50 in another embodiment, with frequency (GHz) on the horizontal axis and return loss (dB) on the vertical axis. Curve C is a return loss curve of the antenna assembly 100 corresponding to the LTE B1 band in one embodiment. Curve D is a return loss curve of the antenna assembly 100 corresponding to the LTE B3 band in one embodiment. Curve E is a return loss curve of the antenna assembly 100 corresponding to the LTE B20 band in one embodiment. Curve F is a return loss curve of the antenna assembly 100 corresponding to the LTE B40 band in one embodiment. Curve G is a return loss curve of the antenna assembly 100 corresponding to the LTE B41 band in one embodiment. Curve C has C1 (2.0339, -14.595) thereon. Curve D has D1 (1.7837, -12.486) thereon. Curve E has E1 (0.81864, -12.295) thereon. Curve F has F1 (2.3557, -25.512). Curve G has G1 (2.5896, -20.407) thereon. It can be seen that the antenna assembly 100 has good antenna performance in the third frequency band (e.g., LTE B20 frequency band) and the fourth frequency band (e.g., LTE B3 frequency band, LTE B1 frequency band, LTE B40 frequency band, LTE B41 frequency band.) and thus has good operation status, and can meet engineering requirements.

Referring to fig. 14, fig. 14 is a graph of the overall efficiency of the system in which the antenna assembly 100 of fig. 7 is excited by the second feed 50 in another embodiment. The horizontal axis is frequency (GHz) and the vertical axis is system total efficiency (dB). Curve c is a system overall efficiency curve of the antenna assembly 100 corresponding to the LTE B1 band in one embodiment. Curve d is the overall system efficiency curve of the antenna assembly 100 for the LTE B3 band in one embodiment. Curve e is the overall system efficiency curve of the antenna assembly 100 for the LTE B20 band in one embodiment. Curve f is a system overall efficiency curve of the antenna assembly 100 corresponding to the LTE B40 band in one embodiment. Curve g is the overall system efficiency curve for the antenna assembly 100 corresponding to the LTE B41 band in one embodiment. Curve c has c1 (2.0431, -4.6083) thereon. The curve d has d1 (1.8, -4.2537). Curve e has e1 (0.8244, -6.6274) thereon. Curve f has f1 (2.3794, -4.3104). Curve g has g1 (2.5982, -4.1249). It can be seen that the antenna assembly 100 has good antenna performance in the third frequency band (e.g., LTE B20 frequency band) and the fourth frequency band (e.g., LTE B3 frequency band, LTE B1 frequency band, LTE B40 frequency band, LTE B41 frequency band.) and thus has good operation status, and can meet engineering requirements.

Next, an electronic device to which the antenna assembly 100 of the above-described embodiment can be mounted will be described. The electronic device may be any of a number of electronic devices including, but not limited to, cellular telephones, smart phones, other wireless communication devices, personal digital assistants, audio players, other media players, music recorders, video recorders, cameras, other media recorders, radios, medical devices, calculators, programmable remote controls, pagers, netbooks, personal Digital Assistants (PDAs), portable Multimedia Players (PMPs), moving picture experts group (MPEG-1 or MPEG-2), audio layer 3 (MP 3) players, portable medical devices, and digital cameras, combinations thereof, and the like.

In some embodiments, the electronic device may include, but is not limited to, an electronic device with communication functions such as a mobile phone, an internet device (MID), an electronic book, a portable play station (Play Station Portable, PSP), or a personal digital assistant (personal DIGITAL ASSISTANT, PDA).

Referring to fig. 15, fig. 15 is an exploded view of an electronic device according to an embodiment of the application, the electronic device 200 may include a middle frame assembly 90 provided with an antenna assembly 100, a display 201 disposed on one side of the middle frame assembly 90 for displaying information, a battery cover 202 connected to the other side of the middle frame assembly 90, a circuit board 203 mounted on the middle frame assembly 90 for controlling the display 201 and the antenna assembly 100, and a battery 204 mounted on the middle frame assembly 90 for supplying power for normal operation of the electronic device 200.

The display 201 may be a Liquid crystal display (Liquid CRYSTAL DISPLAY, LCD) or an Organic Light-Emitting Diode (OLED) display, etc. for displaying information and images.

The material of the middle frame assembly 90 may be a metal such as magnesium alloy, aluminum alloy, stainless steel, etc., but the material is not limited thereto, and may be other insulating materials such as hard materials. The middle frame assembly 90 may be interposed between the display 201 and the battery cover 202. The middle frame assembly 90 may be used to carry a display screen 201. The middle frame assembly 90 is snap-fit connected with the battery cover 202 to form the main housing 80 of the electronic device 200, and a receiving cavity is formed inside the main housing 80. The receiving cavity may be used to receive electronic components such as a camera, a circuit board 203, a battery 204, a processor (disposed on the circuit board 203 and, therefore, may be part of the circuit board 203 in some embodiments), the antenna assembly 100, and various types of sensors in the electronic device 200.

The circuit board 203 is installed in the accommodating chamber, and can be installed at any position in the accommodating chamber. The circuit motherboard 203 may be a motherboard of the electronic device 200. The processor of the electronic device 200 may be provided on the circuit motherboard 203. One, two or more of the functional components such as a motor, a microphone, a speaker, a receiver, an earphone interface, a universal serial bus interface (USB interface), a camera, a distance sensor, an ambient light sensor, and a gyroscope may be integrated on the circuit board 203. Meanwhile, the display screen 201 may be electrically connected to the circuit board 203.

The battery 204 is mounted in the receiving cavity and may be mounted anywhere within the receiving cavity. The battery 204 may be electrically connected to the circuit motherboard 203 to enable the battery 204 to power the electronic device 200. The circuit motherboard 203 may have a power management circuit disposed thereon. The power management circuit is used to distribute the voltage provided by the battery 204 to various electronic components in the electronic device 200, such as the display 201.

The battery cover 202 may be made of the same material as the middle frame assembly 90, although other materials may be used. The battery cover 202 may be integrally formed with the middle frame assembly 90. In some embodiments, battery cover 202 may wrap around middle frame assembly 90, and may carry display 201. The battery cover 202 may have a rear camera hole, a fingerprint recognition module mounting hole, and the like.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Referring to fig. 15 and 16, fig. 16 is a schematic structural diagram of a frame assembly 90 in the embodiment shown in fig. 15. The middle frame assembly 90 may include a substrate 91 for carrying a display screen 201 and a bezel 92 surrounding the substrate 91. Wherein the substrate 91 is disposed opposite to the battery cover 202. The bezel 92 may be adapted for snap-fit connection with the battery cover 202. That is, the substrate 91, the frame 92, and the battery cover 202 define a housing chamber.

The substrate 91 may be a conductive metal, but may be other materials. A ground plane and a feed source may be provided on the substrate 91. The ground plane acts as ground. In some embodiments, the ground plane and feed may not be disposed on the substrate 91, but directly on the circuit motherboard 203. In some embodiments, the substrate 91 may be omitted.

The bezel 92 may be a conductive metal, so the bezel 92 may also be referred to as a "metal bezel". Of course, the frame 92 may be made of other materials, such as an insulating material. The frame 92 may be made of the same material as the substrate 91. The frame 92 may include a first frame 921, a second frame 922, a third frame 923, and a fourth frame 924 connected end to end in sequence. The first frame 921, the second frame 922, the third frame 923, and the fourth frame 924 are disposed around the substrate 91 and can be connected and fixed to the substrate 91. In some embodiments, the bezel 92 may be of unitary construction with the battery cover 202. For example, the frame 92 extends from the edge of the battery cover 202 to the display 201 to be fastened to the display 201.

In some embodiments, the first bezel 921, the second bezel 922, the third bezel 923, and the fourth bezel 924 enclose a rounded rectangle. Of course, other shapes such as circular, triangular, etc. are also possible. In some embodiments, the first frame 921 is disposed opposite the third frame 923, and the second frame 922 is disposed opposite the fourth frame 924.

In some embodiments, the lengths of both the first frame 921 and the third frame 923 are shorter than the length of the second frame 922 and shorter than the length of the fourth frame 92.

It will be appreciated that the center assembly 90 and battery cover 202 may comprise the main housing 80. In some embodiments, the main housing may not be limited to the middle frame assembly 90 and the battery cover 202, but may include other components, which are not described in detail.

Please refer to fig. 16. The antenna assembly 100 may be mounted on the center frame assembly 90. In some embodiments, the antenna assembly 100 may be part of the middle frame assembly 90. Of course, in some embodiments, the antenna assembly 100 may also be mounted in other locations of the main housing 80, such as on the battery cover 202. In some embodiments, the antenna assembly 100 may be machined from the main housing 80. For example, the antenna assembly 100 appears as a slot antenna. In some embodiments, the antenna assembly 100 may be directly secured to the main housing 80.

The radiator 10 is arranged at a frame 92, for example a first frame 921.

In an embodiment, the first feed 20, the second feed 50 may be feeds on the substrate 91 or the circuit motherboard 203. The radiator 10 can be connected with the feed source through the antenna spring plate.

In one embodiment, the ground may be a ground plane on the substrate 91 or the circuit motherboard 203. The radiator 10 can be connected with the ground through the antenna spring.

A slit 901 is provided between the first frame 921 and the substrate 91. The slit 901 may be extended toward the second frame 922 and the fourth frame 924 in the extending direction of the first frame 921, so as to be formed between the first frame 921 and the substrate 91, for example, a ground plane, and a part or all of the first frame 921 may serve as the radiator 10.

In some embodiments, the slit 901 may extend toward the second frame 922 in the extending direction of the first frame 921, so as to form between the second frame 922 and the substrate 91, for example, a ground plane.

In some embodiments, the slit 901 may be extended toward one side of the fourth frame 924 in the extending direction of the first frame 921, so as to form between the fourth frame 924 and the substrate 91, for example, a ground plane.

The radiator 10 of the present application uses the first frame 921, so that the performance loss of the antenna assembly 100 by a human hand can be effectively improved.

It is understood that in order to secure the connection strength between the substrate 91 and the frame 92, for example, the first frame 921, the radiator 10. An insulating material, such as a resin, may be filled between the gaps 901 to realize that the radiator 10 in the antenna assembly 100 is a part of the frame 92, such as the first frame 921, and further improve the appearance of the electronic device 200.

The application adopts the scheme of sharing the radiator, solves the problem of isolation/coexistence, ensures that the total system efficiency of the antenna assembly 100 is good, reduces the requirement of the antenna assembly 100 on the design space of the electronic equipment 200, and has important engineering application benefits.

Next, referring to fig. 17, fig. 17 is a schematic structural diagram of an electronic device 300 according to an embodiment of the application. The electronic device 300 may be a mobile phone, a tablet computer, a notebook computer, a wearable device, etc. The present embodiment is illustrated using a mobile phone as an example. The structure of the electronic device 300 may include RF circuitry 310 (e.g., the antenna assembly 100 in the above-described embodiments), memory 320, input unit 330, display unit 340 (e.g., the display 201 in the above-described embodiments), sensor 350, audio circuitry 360, wiFi module 370, processor 380, and power supply 390 (e.g., the battery 204 in the above-described embodiments), among others. The RF circuit 310, the memory 320, the input unit 330, the display unit 340, the sensor 350, the audio circuit 360, and the WiFi module 370 are respectively connected to the processor 380. The power supply 390 is used to provide power to the entire electronic device 300.

Specifically, RF circuit 310 is used to send and receive signals. Memory 320 is used to store data instruction information. The input unit 330 is used for inputting information, and may specifically include a touch panel 3301 and other input devices 3302 such as operation keys. The display unit 340 may include a display panel 3401 and the like. The sensor 350 includes an infrared sensor, a laser sensor, a position sensor, etc., for detecting a user proximity signal, a distance signal, etc. The speaker 3601 and the microphone (or microphone, or receiver assembly) 3602 are coupled to the processor 380 through the audio circuit 360 for receiving sound signals. The WiFi module 370 is configured to receive and transmit WiFi signals. The processor 380 is used for processing data information of the electronic device.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus may be implemented in other manners. For example, the above-described device embodiments are merely illustrative, e.g., the division of modules or units is merely a logical functional division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The foregoing description is only illustrative of the present application and is not intended to limit the scope of the application, and all equivalent structures or equivalent processes or direct or indirect application in other related technical fields are included in the scope of the present application.

Claims

1. An antenna assembly, comprising:

The radiator is provided with a first free end, a second free end, a first feed point and a first grounding point, wherein the first grounding point is positioned between the first free end and the second free end, and the first feed point is positioned between the first free end and the first grounding point;

2. The antenna assembly of claim 1, wherein the first frequency selective circuit comprises:

The first matching circuit is electrically connected between the first feed point and the first feed source, so that the first feed source is electrically connected with the first feed point through the first matching circuit, the first matching circuit is grounded, and current supporting the first frequency band is configured to flow through the first matching circuit from the ground to be input to the radiator.

3. The antenna assembly of claim 2, wherein the first matching circuit comprises:

A first capacitor electrically connected between the first feed point and the first feed source so that the first feed source is electrically connected with the first feed point through the first capacitor,

And the second capacitor is electrically connected between the first capacitor and the ground, so that the first capacitor is grounded through the second capacitor, and the current supporting the first frequency band is configured to flow through the second capacitor and the first capacitor from the ground to be input into the radiator.

4. The antenna assembly of claim 3, wherein the second capacitor has a capacitance of 1pF.

5. The antenna assembly of claim 1, wherein the tuning circuit comprises:

and the third capacitor is electrically connected between the first grounding point and the ground, so that the first grounding point is grounded through the third capacitor, and the current supporting the second frequency band is configured to flow through the third capacitor from the ground to be input into the radiator.

6. The antenna assembly of claim 5, wherein the third capacitor has a capacitance of 2.7pF.

7. The antenna assembly of any of claims 1-6, wherein the first feed is configured to excite a radiating portion of the radiator located between the first feed point and the first free end to produce a first resonant mode supporting the first frequency band, the first resonant mode being a 1/4 wavelength inverted F antenna IFA antenna mode, currents supporting the first frequency band being configured to flow from the first feed point to the first free end.

8. The antenna assembly of claim 7, wherein the first frequency band comprises a WiFi5G frequency band.

9. The antenna assembly of any of claims 1-6, wherein the first feed is configured to excite a radiating portion of the radiator located between the first ground point and the first free end to produce a second resonant mode supporting the second frequency band, the second resonant mode being a 1/4 wavelength left-hand antenna mode, currents supporting the second frequency band being configured to flow from the first ground point to the first free end.

10. The antenna assembly of claim 9, wherein the second frequency band comprises a new air interface N78 frequency band.

11. The antenna assembly of claim 1, wherein the radiator further has a second feed point located between the first ground point and the second free end, the antenna assembly further comprising:

A second feed for exciting the radiator;

The second frequency selection circuit is electrically connected between the second feed point and the second feed source, so that the second feed source is electrically connected with the second feed point through the second frequency selection circuit, the second frequency selection circuit is grounded, the first frequency selection circuit is configured to be in a high-impedance state when the second feed source excites the radiator and in a low-impedance state when the first feed source excites the radiator, and the second frequency selection circuit is configured to be in a high-impedance state when the first feed source excites the radiator and in a low-impedance state when the second feed source excites the radiator.

12. The antenna assembly of claim 11, wherein the first frequency selective circuit is configured to be turned off when the second feed excites the radiator and turned on when the first feed excites the radiator, and the second frequency selective circuit is configured to be turned off when the first feed excites the radiator and turned on when the second feed excites the radiator.

13. The antenna assembly according to any one of claims 11-12, wherein the first frequency selection circuit comprises:

The first matching circuit is connected with the first feed source and grounded;

The first filter circuit is electrically connected between the first feed point and the first matching circuit, so that the first matching circuit is electrically connected with the first feed point through the first filter circuit, current supporting the first frequency band is configured to flow through the first matching circuit from ground to be input into the radiator, and the first filter circuit is configured to be disconnected when the second feed source excites the radiator and connected when the first feed source excites the radiator.

14. The antenna assembly of claim 13, wherein the first filter circuit comprises:

A fourth capacitor electrically connected between the first feeding point and the first matching circuit, so that the first matching circuit is electrically connected with the first feeding point through the fourth capacitor, and a current supporting the first frequency band is configured to flow through the fourth capacitor;

and the first inductor is electrically connected between the first feed point and the first matching circuit, so that the first matching circuit is electrically connected with the first feed point through the first inductor.

15. The antenna assembly of any of claims 11-12, wherein the second frequency selective circuit has a first electrical connection terminal electrically connected to the second feed point and a second electrical connection terminal electrically connected to the second feed point, the first electrical connection terminal being electrically connected to the second electrical connection terminal, the second frequency selective circuit comprising:

The second matching circuit is electrically connected between the first electric connection end and the ground so that the first electric connection end is grounded through the second matching circuit;

The second filter circuit is electrically connected between the first electric connection end and the ground so that the first electric connection end is grounded through the second filter circuit; the second filter circuit is configured to control the second frequency selection circuit to be turned off when the first feed excites the radiator and turned on when the second feed excites the radiator.

16. The antenna assembly of any one of claims 11-12, wherein the radiator further has a second ground point between the first ground point and the second feed point, the second ground point being grounded, the second feed configured to excite a radiating portion of the radiator between the second ground point and the first free end to produce a third resonant mode supporting a third frequency band, the third resonant mode being an IFA antenna mode, current of the third resonant mode being configured to flow from the second ground point to the first free end.

17. The antenna assembly of claim 16, wherein the third frequency band comprises a long term evolution, LTE, B20, frequency band.

18. The antenna assembly of any one of claims 11-12, wherein the radiator further has a second ground point between the first ground point and the second feed point, the second ground point being grounded, the second feed configured to excite a radiating portion of the radiator between the second ground point and the second free end to produce a fourth resonant mode supporting a fourth frequency band, the fourth resonant mode being an IFA antenna mode, a current of the fourth resonant mode being configured to flow from the second ground point to the second free end.

19. The antenna assembly of claim 18, wherein the fourth frequency band comprises at least one of LTEB frequency bands, LTE B3 frequency bands, LTE B39 frequency bands, LTE B40 frequency bands, or LTE B41 frequency bands.

20. The antenna assembly of claim 18, wherein the radiator further has a third ground point located between the second feed point and the second free end, the antenna assembly further comprising:

And the switching circuit is electrically connected between the third grounding point and the ground so as to enable the third grounding point to be grounded through the switching circuit, and the switching circuit is used for adjusting the frequency of the fourth frequency band.

21. The antenna assembly of claim 20, wherein the switching circuit comprises:

The switching switch is provided with a plurality of connecting ends, a switching part and a common end electrically connected with the third grounding point, wherein the switching part is electrically connected with the common end and is configured to be electrically connected to one connecting end of the plurality of connecting ends under the control of a control signal; and

And one end of the at least one frequency selecting branch is electrically connected with the connecting ends in one-to-one correspondence, and the other end of the at least one frequency selecting branch is grounded.

22. The antenna assembly of claim 21, wherein each of the at least one frequency selective branches comprises a capacitance or an inductance.

23. An antenna assembly, comprising:

And the switching circuit is electrically connected between the third grounding point and the ground so as to enable the third grounding point to be grounded through the switching circuit, and the switching circuit is used for adjusting the frequency of the frequency band supported by the fourth resonance mode.

24. A center assembly, comprising:

A substrate provided with a ground plane;

the frame is arranged around the substrate in a surrounding mode; and

An antenna assembly as claimed in any one of claims 1 to 23, wherein the radiator is disposed on the bezel and a gap is provided between the radiator and the ground plane.

25. An electronic device, comprising:

A middle frame assembly comprising:

A substrate;

The antenna assembly of any of claims 1-23, the radiator disposed on the first bezel;