Patent Description:
Currently, to enhance a sense of quality of electronic devices such as mobile phones and personal digital assistants, metal is increasingly applied to industry design (industry design, ID) of the electronic devices, for example, a metal frame. In the industry design that uses the metal frame, designing the metal frame into an antenna becomes a direction of antenna design.

In the prior art, low band (LB) performance is implemented mainly by using a side longitudinal component, for example, a side inverted-F antenna (inverted-F antenna, IFA) mode or an active antenna longitudinal mode. However, as big screens such as curved screens become popular, side metal frame bodies of mobile phones become thinner (narrower). Therefore, as curved screens approach the extreme and side frame bodies and side surroundings become weaker, antenna performance with a side frame body as a main radiation antenna declines sharply, and cannot meet a requirement for low band (LB) performance. <CIT> discusses an antenna device composed of a metal frame of an electronic device. <CIT> discusses a mid-frame assembly of an electronic device in which the antenna component of the mid-frame assembly of the electronic device has good performance. <CIT> discusses an electronic device which may include a conductive housing and an antenna. <CIT> discusses an antenna structure including a metallic member.

In view of this, it is necessary to provide an antenna structure that can effectively improve low band (LB) radiation performance, and an electronic device having the antenna structure.

According to a first aspect, this application provides an an electronic device according to appended claim <NUM>.

The present invention will be further described with reference to the accompanying drawings in the following specific embodiments.

The following clearly describes the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are merely some but not all of the embodiments of the present invention.

It should be noted that when one element is, as stated, "electrically connected to" another element, the element may be directly on the another element, or there may be an element in between. When it is considered that one element is "electrically connected to" another element, it may be contact connection such as wire connection, or non-contact connection such as non-contact coupling.

Unless otherwise defined, all technical and scientific terms as used herein have the same meanings as those usually understood by a person skilled in the art of the present invention. The terms used in the specification of the present invention herein are for description of the particular embodiments only and are not intended to limit the present invention.

The following describes in detail some embodiments of the present invention with reference to the accompanying drawings. The following embodiments and features in the embodiments may be combined, provided that no conflict occurs.

Referring to <FIG> and <FIG>, an example implementation of the present invention provides an antenna structure <NUM> (referring to <FIG>). The antenna structure may be applied to an electronic device <NUM> such as a mobile phone, a tablet computer, or a personal digital assistant (personal digital assistant, PDA) and is configured to transmit and receive radio waves, so as to transmit and exchange radio signals.

It may be understood that the electronic device <NUM> may use one or more of the following communications technologies: a Bluetooth (Bluetooth, BT) communications technology, a global positioning system (global positioning system, GPS) communications technology, a wireless fidelity (wireless fidelity, Wi-Fi) communications technology, a global system for mobile communications (global system for mobile communications, GSM) communications technology, a wideband code division multiple access (wideband code division multiple access, WCDMA) communications technology, a long term evolution (long term evolution, LTE) communications technology, a <NUM> communications technology, a SUB-<NUM> communications technology, another future communications technology, and the like.

The electronic device <NUM> includes a housing <NUM> and a display unit <NUM>. The housing <NUM> includes at least a frame <NUM> and a back plate <NUM>. The frame <NUM> is substantially of a ring structure and is made of metal or another conductive material. The back plate <NUM> is disposed on an edge of the frame <NUM>. The back plate <NUM> may be made of metal or another conductive material. Certainly, the back plate <NUM> may alternatively be made of an insulating material such as glass or plastic.

It may be understood that, in this embodiment, an opening (not shown in the figure) is provided on a side of the frame <NUM> facing toward the back plate <NUM> and is configured to accommodate the display unit <NUM>. It may be understood that the display unit <NUM> is provided with a display flat surface, and the display flat surface is exposed out of the opening. It may be understood that the display unit <NUM> may be combined with a touch sensor to form a touch screen. The touch sensor may also be referred to as a touch panel or a touch-sensitive panel.

Also referring to <FIG>, the antenna structure <NUM> includes at least a frame body, a first feed-in part <NUM>, a second feed-in part <NUM>, a first connection part <NUM>, a second connection part <NUM>, and a third connection part <NUM>.

The frame body is at least partially made of a metal material. In this embodiment, the frame body is the frame <NUM> of the electronic device <NUM>. The frame <NUM> includes at least a first part <NUM>, a second part <NUM>, and a third part <NUM>. In this embodiment, the first part <NUM> is a bottom end of the electronic device <NUM>, that is, the first part <NUM> is a bottom metal frame of the electronic device <NUM>. The antenna structure <NUM> forms a lower antenna of the electronic device <NUM>. The second part <NUM> and the third part <NUM> face toward each other, are disposed at two ends of the first part <NUM> respectively, and are preferably arranged vertically. In this embodiment, a length of the second part <NUM> or a length of the third part <NUM> is greater than a length of the first part <NUM>. That is, both the second part <NUM> and the third part <NUM> are side metal frames of the electronic device <NUM>.

At least one slot is further provided in the frame <NUM>. In this embodiment, three slots are provided in the frame <NUM>: a first slot <NUM>, a second slot <NUM>, and a third slot <NUM>. The first slot <NUM> and the third slot <NUM> are provided in the first part <NUM> at an interval. The second slot <NUM> is provided in the second part <NUM>. The first slot <NUM> is closer to the second part <NUM> than the third slot <NUM>. The third slot <NUM> is closer to the third part <NUM> than the first slot <NUM>.

It may be understood that, in this embodiment, the antenna structure <NUM> further includes a ground point <NUM>. The ground point <NUM> is disposed on the third part <NUM>.

In this embodiment, the first slot <NUM>, the second slot <NUM>, and the third slot <NUM> all run through and cut off the frame <NUM>. The at least one slot and the ground point <NUM> jointly mark out at least two radiation parts on the frame <NUM>. In this embodiment, the first slot <NUM>, the second slot <NUM>, the third slot <NUM>, and the ground point <NUM> jointly mark out a first radiation part F1 and a second radiation part F2 on the frame <NUM>. In this embodiment, a part of the frame <NUM> between the first slot <NUM> and the second slot <NUM> forms the first radiation part F1. A part of the frame <NUM> between the third slot <NUM> and the ground point <NUM> forms the second radiation part F2. That is, the first radiation part F1 is disposed in a lower right corner of the electronic device <NUM> and is formed with a part of the first part <NUM> and a part of the second part <NUM>. The second radiation part F2 is disposed in a lower left corner of the electronic device <NUM> and is formed with a part of the first part <NUM> and a part of the third part <NUM>. An electrical length of the first radiation part F1 is greater than an electrical length of the second radiation part F2.

It may be understood that, in this embodiment, the first slot <NUM>, the second slot <NUM>, and the third slot <NUM> each are filled with insulating material such as plastic, rubber, glass, wood, or ceramic, but are not limited thereto.

It may be understood that, in this embodiment, a width of the first slot <NUM>, a width of the second slot <NUM>, and a width of the third slot <NUM> are all small, for example, may range from <NUM> millimeter (mm) to <NUM>. In a preferred solution, a width of the first slot <NUM>, a width of the second slot <NUM>, and a width of the third slot <NUM> each may be <NUM>, <NUM>, or <NUM>.

It may be understood that, in this embodiment, the first feed-in part <NUM> is located in the housing <NUM>. The first feed-in part <NUM> is disposed on the first radiation part F1 and located on the first part <NUM>. The first feed-in part <NUM> may be electrically connected to a first feed <NUM> by using a dome, a microstrip, a strip, a coaxial cable, or the like, to feed a current signal into the first radiation part F1.

The second feed-in part <NUM> is disposed in the housing <NUM>. The second feed-in part <NUM> is disposed on the second radiation part F2 and located on the first part <NUM>. The second feed-in part <NUM> may be electrically connected to a second feed <NUM> by using a dome, a microstrip, a strip, a coaxial cable, or the like, to feed a current signal into the second radiation part F2.

It may be understood that, in this embodiment, the first feed-in part <NUM> and the second feed-in part <NUM> may be made of a material such as iron, copper foil, or a conductor in a laser direct structuring (Laser Direct structuring, LDS) process.

The first connection part <NUM> is disposed on the first radiation part F1 and located on the second part <NUM>. The second connection part <NUM> is disposed on the first radiation part F1 and located on the second part <NUM>. That is, in this embodiment, the first connection part <NUM> and the second connection part <NUM> are disposed on the second part <NUM> at an interval, and a distance from the first connection part <NUM> to the second slot <NUM> is less than a distance from the second connection part <NUM> to the second slot <NUM>. That is, the first connection part <NUM> is closer to the second slot <NUM> than the second connection part <NUM>.

The third connection part <NUM> is disposed in the housing <NUM>. In this embodiment, the third connection part <NUM> is disposed on the second radiation part F2 and located on the first part <NUM>. The third connection part <NUM> is closer to the third part <NUM> than the second feed-in part <NUM>.

It may be understood that, in this embodiment, an electrical length L (referring to <FIG>) of the first radiation part F1 is adjusted, so that the electrical length L is approximately one-half of a wavelength corresponding to resonance frequency thereof. Therefore, when current is fed into the first feed-in part <NUM>, the first radiation part F1 may generate a resonance by using a half wave mode. In this case, a radiation mode of the antenna structure <NUM> is a longitudinal mode. In addition, when current is fed into the first feed-in part <NUM>, the first radiation part F1 may alternatively generate a resonance by using a composite right/left handed (composite right/left handed, CRLH) mode. In this case, a radiation mode of the antenna structure <NUM> is a transverse mode. That is, when current is fed into the first feed-in part <NUM>, the first radiation part F1 may generate a radiation signal in a first radiation band by using both the CRLH mode and the half wave mode to initiate a first operating mode. In this embodiment, the first operating mode is a low band (low band, LB) mode. Frequency of the first radiation band includes, but is not limited to bands such as LTE B28/B5/B8.

It may be understood that the longitudinal mode may refer to a radiation mode that the longitudinal side metal frame (for example, the second part <NUM>) serves as a main radiator to radiate outward. The transverse mode may refer to a radiation mode that the transverse bottom metal frame (for example, the first part <NUM>) serves as a main radiator to radiate outward.

It may be understood that when current is fed into the first feed-in part <NUM>, the CRLH mode is used as a main resonance mode, and this mode has, different from the inverted F antenna (inverted F antenna, IFA) mode, the characteristics of miniaturization and being mainly based on transverse components, thereby being less affected by side radiators or curved screens. In addition, the antenna structure <NUM> with a slot (that is, the second slot <NUM>) provided in its side, for example, the second part <NUM> may help improve a longitudinal component of a side radiator, so as to ensure that the antenna structure <NUM> has relatively good LB radiation performance.

When current is fed into the second feed-in part <NUM>, the antenna structure <NUM> may generate a radiation signal in a second radiation band by using both the CRLH mode and a parasitic mode to initiate a second operating mode. The second operating mode is a medium/high band (middle/high band, MHB) mode. Frequency of the second radiation band includes, but is not limited to bands such as LTE B1/B3/B4/B7/B38/B39/B40/B41, WCDMA B1/B2, and GSM <NUM>/<NUM>.

It may be understood that with the development of information technologies, the public enjoys convenience brought by the information technologies and also focuses on harm of electromagnetic radiation of wireless communications terminals to human bodies. A specific absorption rate (Specific Absorption Rate, SAR) is an important indicator of a mobile phone and also is the content that an antenna engineer pays the special attention to during antenna design. Generally, a total radiated power (Total Radiated Power, TRP) of the electronic device is closely associated with SAR. However, in actual antenna design, radiation power of a mobile phone is reduced to control the SAR under normal conditions. For example, <FIG> are schematic diagrams of existing three antenna solutions. In the three antenna solutions, an SAR sensor (Sensor) is added for scenario determination to obtain different SAR values, and then radiation power of a mobile phone is reduced to meet an SAR requirement. However, only reducing radiation power of a mobile terminal to control the SAR damages radio performance of a product, affects user experience, and also reduces competitiveness of a product.

In the antenna structure <NUM>, the second radiation part F2 uses two resonance modes, including a CRLH mode and a parasitic mode. The CRLH mode is located on a side of the second feed-in part <NUM> The CRLH mode is located on a same side as the second feed-in part <NUM>. Therefore, a current distribution area of the CRLH mode is increased (for example, an electrical length of the second radiation part F2 is adjusted or increased), the parasitic mode of the second radiation part F2 strides across the first slot <NUM> and the third slot <NUM>, and a part of the frame <NUM> between the first slot <NUM> and the first connection part <NUM> forms a parasitic stub, so as to disperse current distribution, so that the antenna structure <NUM> may operate on a middle/high band and has the characteristic of relatively low SAR without reducing its radiation power. That is, as shown in <FIG>, an area <NUM> forms an MHB area of the antenna structure <NUM>. That is, the second radiation part F2 is mainly in the CRLH mode, the parasitic mode of the second radiation part F2 strides across the first slot <NUM> and the third slot <NUM>, so that a part of the frame <NUM> between the first slot <NUM> and the first connection part <NUM> forms a parasitic stub. In addition, in the figure, an area <NUM> forms an LB area of the antenna structure <NUM>.

<FIG> are schematic diagrams of three different MHB design solutions. <FIG> uses a long left handed and far parasitic mode, <FIG> uses a short left handed and far parasitic mode, and <FIG> uses a short left handed and near parasitic mode. Long left handed and short left handed mean that an electrical length of the second radiation part F2 in <FIG> is greater than an electrical length of the second radiation part F2 in <FIG>. Far parasitic and near parasitic refer to a parasitic stub farther away from the second radiation part F2 (for example, a part of the frame <NUM> between the first slot <NUM> and the first connection part <NUM>, referring to <FIG>) and a parasitic stub nearer to the second radiation part F2 (for example, a part of the frame <NUM> between the first slot <NUM> and the third slot <NUM>, referring to <FIG>), respectively. Clearly, it has been found through simulation for SAR values in the foregoing three solutions that, in the solution in the <FIG> (that is, the solution used in this specification), a component tangent to a magnetic field (H field) is more dispersed, and the characteristic of a relatively low SAR value is implemented.

It may be understood that, in this embodiment, the antenna structure <NUM> further includes a first tuning unit SW1, a second tuning unit SW2, and a third tuning unit SW3. One end of the first tuning unit SW1 is electrically connected to the first feed-in part <NUM>, and the other end is grounded. The first tuning unit SW1 is configured to perform port matching and tuning and frequency adjustment on the first radiation part F1.

One end of the second tuning unit SW2 is electrically connected to the first connection part <NUM> and the second connection part <NUM>. The other end of the second tuning unit SW2 is grounded.

It may be understood that, in this embodiment, the second tuning unit SW2 forms a multiplex switch, that is, the first connection part <NUM> and the second connection part <NUM> share the second tuning unit SW2. The first connection part <NUM> may be switched to different tuning branches by using the second tuning unit SW2, so as to adjust a frequency and longitudinal component. For example, the first connection part <NUM> may be switched or adjusted to a zero-ohm resistor or a <NUM>-nanohenry (nH)/<NUM>-nH inductor by using the second tuning unit SW2, so as to slightly adjust a frequency and longitudinal component of the first radiation part F1. The second connection part <NUM> adjusts a parasitic resonance frequency of the second radiation part F2 by using the second tuning unit SW2.

One end of the third tuning unit SW3 is electrically connected to the second feed-in part <NUM> and the third connection part <NUM>, and the other end is grounded. The third tuning unit SW3 is configured to perform frequency tuning on the CRLH mode of the second radiation part F2. In addition, frequency tuning may be performed on the parasitic mode of the second radiation part F2 by using the first tuning unit SW1. In a preferred solution auxiliary tuning may be further performed on the parasitic mode of the second radiation part F2 by using the second tuning unit SW2 on the basis of the first tuning unit SW1. That is, tuning is performed on the CRLH mode of the second radiation part F2 mainly by using the third tuning unit SW3. Tuning is performed on the parasitic mode of the second radiation part F2 by using the first tuning unit SW1 and the second tuning unit SW2.

It may be understood that the foregoing tuning units, for example, the first tuning unit SW1, the second tuning unit SW2, and the third tuning unit SW3 each may, but are not limited to, be formed by combining a plurality of single pole single throw (single pole single throw, SPST) switches. For example, referring to <FIG>, the tuning unit may include at least one switch unit, for example, three SPST switches: a switch <NUM>, a switch <NUM>, and a switch <NUM>. One end of each switch unit is grounded, and the other end may be connected to a corresponding tuning branch. For example, the switch <NUM> is connected to a tuning branch L1, the switch <NUM> is connected to a tuning branch L2, and a switch <NUM> is connected to a tuning branch L3. The tuning branches L1, L2, and L3 each may include a capacitor or an inductor. The tuning units may selectively turn on different tuning branches to implement frequency adjustment.

Certainly, in other embodiments, the tuning units, for example, the first tuning unit SW1, the second tuning unit SW2, and the third tuning unit SW3 may further include another type of switch units, and are not limited to the foregoing SPST switches.

It may be understood that, in this embodiment, the antenna structure <NUM> cooperates with joint tuning of the tuning units, for example, the first tuning unit SW1, the second tuning unit SW2, and the third tuning unit SW3, so that free space (free space, FS) efficiency in the low band mode can be improved. In addition, parasitic resonance in a middle/high band mode can be adjusted, so that performance and low SAR characteristic in the middle/high band mode are ensured.

It may be understood that FS efficiency refers to efficiency of the antenna structure <NUM> in the low band mode when the electronic device <NUM> is not held by a user.

<FIG> is a curve graph of S parameter (scattering parameter) and radiation efficiency of the antenna structure <NUM> operating in a low band mode. A curve S41 indicates S11 values of the antenna structure <NUM> operating on an LTE B28 band. A curve S42 indicates the S11 values of the antenna structure <NUM> operating on an LTE B5 band. A curve S43 indicates the S11 values of the antenna structure <NUM> operating on an LTE B8 band. A curve S44 indicates radiation efficiency of the antenna structure <NUM> operating on an LTE B28 band. A curve S45 indicates the radiation efficiency of the antenna structure <NUM> operating on the LTE B5 band. A curve S46 indicates the radiation efficiency of the antenna structure <NUM> operating on the LTE B8 band. A curve S47 indicates system efficiency of the antenna structure <NUM> operating on the LTE B28 band. A curve S48 indicates the system efficiency of the antenna structure <NUM> operating on the LTE B5 band. A curve S49 indicates the system efficiency of the antenna structure <NUM> operating on the LTE B8 band.

<FIG> is a curve graph of S parameter (scattering parameter) and system efficiency of the antenna structure <NUM> operating on an LTE B5 band. A curve S51 indicates S11 values of the antenna structure <NUM> operating on the an LTE B5 band. A curve S52 indicates system efficiency of the antenna structure <NUM> operating on the LTE B5 band.

<FIG> is a schematic current diagram of a resonance <NUM> of the antenna structure <NUM> operating on an LTE B5 band. <FIG> is a schematic current diagram of a resonance <NUM> of the antenna structure <NUM> operating on an LTE B5 band. It may be learned from <FIG> that as the first radiation part F1 performs feeding at the bottom, the resonance <NUM> radiates mainly by using the CRLH mode, that is, the transverse mode. In addition, in a side grounding position of the antenna structure <NUM>, that is, a position of the first connection part <NUM> and the second connection part <NUM>, the frame body (that is, the first radiation part F1) is in an antenna large-current area to form a maximum current density Jmax. Therefore, a parasitic resistor that includes the second tuning unit SW2 greatly affects low band efficiency of the antenna structure <NUM>. It may be learned from <FIG> and <FIG> that when the first radiation part F1 operates at the resonance <NUM>, the resonance <NUM> radiates mainly by using the half wave mode, that is, the longitudinal mode. In addition, current is fed into the first feed-in part <NUM>, flows through the first radiation part F1, and then radiates out of the first slot <NUM> and the second slot <NUM> in two ends of the first radiation part F1.

<FIG> and <FIG> each illustrate an effect of on-resistance (Ron), generated by the first connection part <NUM> connected to the second tuning unit SW2, on antenna performance. A curve S81 indicates S11 values of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms. A curve S82 indicates the S11 values of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms. A curve S83 indicates the S11 values of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohm. A curve S84 indicates the S11 values of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohm. A curve S85 indicates the S11 values of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms. A curve S91 indicates radiation efficiency of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms. A curve S92 indicates the radiation efficiency of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms. A curve S93 indicates the radiation efficiency of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohm. A curve S94 indicates the radiation efficiency of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohm. A curve S95 indicates the radiation efficiency of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms.

Clearly, it may be learned from <FIG> and <FIG> that when on-resistance (Ron) is <NUM> ohms, the effect is approximately <NUM> dB. When on-resistance (Ron) is <NUM> ohm, the effect is approximately <NUM> dB. That is, an effect of on-resistance (Ron) of the first connection part <NUM> on antenna efficiency is relatively large. Therefore, in this embodiment, for a low band (LB), the first connection part <NUM> may be designed to be directly grounded, for example, directly grounded by using a zero-ohm resistor other than on-resistance (Ron) of the second tuning unit SW2.

<FIG> and <FIG> each illustrate an effect of on-resistance (Ron), generated by the second connection part <NUM> connected to the second tuning unit SW2, on antenna performance. A curve S101 indicates S11 values of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms. A curve S102 indicates the S11 values of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohm. A curve S103 indicates the S11 values of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms. A curve S111 indicates radiation efficiency of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms. A curve S112 indicates the radiation efficiency of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohm. A curve S113 indicates the radiation efficiency of the antenna structure <NUM> when on-resistance (Ron) is <NUM> ohms.

Clearly, it may be learned from <FIG> and <FIG> that when the second tuning unit SW2 uses three single pole single throw (single pole single throw, SPST) switches, on-resistance (Ron) of the second tuning unit SW2 is <NUM> ohms, and an effect is approximately <NUM> dB. When the second tuning unit SW2 uses four SPST switches, on-resistance (Ron) of the second tuning unit SW2 is <NUM> ohm, and an effect is approximately <NUM> dB. That is, an effect of the second connection part <NUM> on the antenna structure <NUM> is relatively small. Therefore, switches with relatively small on-resistance (Ron), for example, 4SPST switches may be selected, so as to reduce an effect of on-resistance (Ron) of the second connection part <NUM> on antenna efficiency when the first tuning unit SW1 is used to perform port tuning in a low band.

It may be understood that <FIG> is a curve graph of S parameter (scattering parameter) and radiation efficiency of the antenna structure <NUM> operating on an LTE B28 band when the antenna structure <NUM> is provided with a second slot <NUM> or not provided with a second slot <NUM> on a side. A curve S121 indicates S11 values of the antenna structure <NUM> operating on an LTE B28 band when the second slot <NUM> is provided. A curve S122 indicates radiation efficiency of the antenna structure <NUM> operating on an LTE B28 band when the second slot <NUM> is provided. A curve S123 indicates system efficiency of the antenna structure <NUM> operating on an LTE B28 band when the second slot <NUM> is provided. A curve S124 indicates the S11 values of the antenna structure <NUM> operating on an LTE B28 band when the second slot <NUM> is not provided. A curve S125 indicates the radiation efficiency of the antenna structure <NUM> operating on an LTE B28 band when the second slot <NUM> is not provided. A curve S126 indicates the system efficiency of the antenna structure <NUM> operating on an LTE B28 band when the second slot <NUM> is not provided.

<FIG> is a curve graph of S parameter (scattering parameter) and radiation efficiency of the antenna structure <NUM> operating on an LTE B5 band when the antenna structure <NUM> is provided with a second slot <NUM> or not provided with a second slot <NUM> on a side. A curve S131 indicates S11 values of the antenna structure <NUM> operating on an LTE B5 band when the second slot <NUM> is provided. A curve S132 indicates radiation efficiency of the antenna structure <NUM> operating on the LTE B5 band when the second slot <NUM> is provided. A curve S133 indicates system efficiency of the antenna structure <NUM> operating on the LTE B5 band when the second slot <NUM> is provided. A curve S134 indicates the S11 values of the antenna structure <NUM> operating on the LTE B5 band when the second slot <NUM> is not provided. A curve S135 indicates the radiation efficiency of the antenna structure <NUM> operating on the LTE B5 band when the second slot <NUM> is not provided. A curve S136 indicates the system efficiency of the antenna structure <NUM> operating on the LTE B5 band when the second slot <NUM> is not provided.

<FIG> is a curve graph of S parameter (scattering parameter) and radiation efficiency of the antenna structure <NUM> operating on an LTE B8 band when the antenna structure <NUM> is provided with a second slot <NUM> or not provided with a second slot <NUM> on a side. A curve S141 indicates S11 values of the antenna structure <NUM> operating on an LTE B8 band when the second slot <NUM> is provided. A curve S142 indicates radiation efficiency of the antenna structure <NUM> operating on an LTE B8 band when the second slot <NUM> is provided. A curve S143 indicates system efficiency of the antenna structure <NUM> operating on an LTE B8 band when the second slot <NUM> is provided. A curve S144 indicates the S11 values of the antenna structure <NUM> operating on an LTE B8 band when the second slot <NUM> is not provided. A curve S145 indicates the radiation efficiency of the antenna structure <NUM> operating on an LTE B8 band when the second slot <NUM> is not provided. A curve S146 indicates the system efficiency of the antenna structure <NUM> operating on an LTE B8 band when the second slot <NUM> is not provided.

Clearly, it may be learned from <FIG> that when the antenna structure <NUM> is provided with the second slot <NUM>, low band (LB) performance of the antenna structure <NUM> is improved by <NUM> dB to <NUM> dB compared with an existing solution in which the slot is not provided, and relatively good FS performance is implemented.

It may be understood that referring back to <FIG>, in this embodiment, the electronic device <NUM> further includes at least one electronic element. In this embodiment, the electronic device <NUM> includes at least three electronic elements: a first electronic element <NUM>, a second electronic element <NUM>, and a third electronic element <NUM>. The first electronic element <NUM>, the second electronic element <NUM>, and the third electronic element <NUM> are all disposed in the housing <NUM>.

In this embodiment, the first electronic element <NUM> is a universal serial bus (Universal Serial Bus, USB) interface module. The first electronic element <NUM> is located between the first slot <NUM> and the third slot <NUM>. The second electronic element <NUM> is a sound cavity. The second electronic element <NUM> is disposed between the third slot <NUM> and the third part <NUM>. The third electronic element <NUM> is a subscriber identity module (Subscriber Identity Module, SIM) card holder. The third electronic element <NUM> is disposed between the third first feed-in part <NUM> and the second part <NUM>.

It may be understood that, in other embodiments, a part of the frame <NUM> between the first slot <NUM> and the third slot <NUM> in the antenna structure <NUM> may alternatively form a parasitic stub F3 in a low band mode. The parasitic stub F3 is spaced from both the first radiation part F1 and the second radiation part F2, that is, arranged in an overhanging manner. <FIG> is a curve graph of S parameter (scattering parameter) and radiation efficiency of the antenna structure <NUM> operating on an LTE B28 band when tuning is performed or not performed on the parasitic stub F3. A curve S151 indicates S11 values of the antenna structure <NUM> operating on an LTE B28 band when tuning is not performed on the parasitic stub F3. A curve S152 indicates radiation efficiency of the antenna structure <NUM> operating on an LTE B28 band when tuning is not performed on the parasitic stub F3. A curve S153 indicates the S11 values of the antenna structure <NUM> operating on an LTE B28 band when tuning is performed on the parasitic stub F3. A curve S154 indicates the radiation efficiency of the antenna structure <NUM> operating on an LTE B28 band when tuning is performed on the parasitic stub F3.

Clearly, when a part of the frame <NUM> between the first slot <NUM> and the third slot <NUM> in the antenna structure <NUM> forms the parasitic stub F3 in a low band mode, the antenna structure <NUM> may generate an additional resonance <NUM>. It may be learned from <FIG> that when tuning is performed on the parasitic stub F3, the resonance <NUM> may be shifted into an effective band of the first radiation part F1, and radiation efficiency in the LTE B28 band is improved significantly.

It may be understood that, in an embodiment, tuning may be performed on the parasitic stub F3 in a low band mode by using the first tuning unit SW1, that is, multiplexing the first tuning unit SW1. Certainly, in other embodiments, a corresponding switch unit may also be additionally arranged, to perform tuning on the parasitic stub F3 in a low band mode.

It may be understood that, in this embodiment, the second radiation part F2 is disposed on a same side as the second electronic element <NUM>. Certainly, in other embodiments, position of the second radiation part F2 may be adjusted as needed. For example, the second radiation part F2 may be disposed on a same side as the third electronic element <NUM>, while the first radiation part F1 is disposed on a side of the second electronic element <NUM>. That is, positions of the first radiation part F1 and the second radiation part F2 may be adjusted (for example, be interchanged) as needed.

It may be understood that, in this embodiment, the antenna structure <NUM> performs separate feeding by using a low band and middle/high band separate feed-in mode, that is, by using the first feed-in part <NUM> and the second feed-in part <NUM>, and is provided with the first tuning unit SW1, the second tuning unit SW2, and the third tuning unit SW3. An on-off state of the first tuning unit SW1, an on-off state of the second tuning unit SW2, and an on-off state of the third tuning unit SW3 are controlled/adjusted, so that full coverage of LB/MB/HB is effectively implemented, and also a middle/high band (MHB) low SAR characteristic and relatively good low band (LB) radiation performance are implemented.

It may be understood that, as described above, in this embodiment, the frame body of the antenna structure <NUM> is directly formed by the frame <NUM> of the electronic device <NUM>, that is, the chassis (frame) of the electronic device <NUM> is made of a metal material, and the antenna structure <NUM> is a metal frame antenna. Certainly, in other embodiments, the antenna structure <NUM> is not limited to the metal frame antenna, and may alternatively be a mode decoration antenna (Mode decoration antenna, MDA) or another antenna. For example, when the antenna structure <NUM> is an MDA antenna, a metal member in the chassis of the electronic device <NUM> is used as the frame body to implement a radiation function. The chassis of the electronic device <NUM> is made of an insulating material such as plastic, and the metal member is integrated with the chassis through insert molding.

In conclusion, as full curved screens approach the extreme, the antenna structure <NUM> in the present invention may implement both middle/high band (MHB) low SAR and low band (LB) radiation performance. That is, slot position and slot width of the antenna are designed, and frame body position and slot coupling current strength are adjusted, so as to affect a distribution concentrated and dispersed degree of current on the antenna frame body. The antenna structure <NUM> increases a current distribution area of a middle/high band (MHB) CRLH mode (for example, adjusts an electrical length of the second radiation part F2) and also cooperates with a parasitic frame body of a middle/high band (MHB) to shunt current, so as to reduce the SAR. In addition, for a slot (that is, the second slot <NUM>) provided in the side frame body, a low band (LB) bottom feed is used, and the CRLH mode is mainly used as the resonance mode. Different from an IFA mode, the CRLH mode has the characteristics of miniaturization and being mainly based on transverse components, thereby being less affected by side curved screens. Further, side slots can help improve a side longitudinal component; in addition, joint tuning of switches can improve low band (LB) FS efficiency and also adjust a middle/high band (MHB) parasitic resonance, so that characteristics of middle/high band (MHB) performance and low SAR are ensured, and power does not need to be greatly reduced to control the SAR.

Claim 1:
An electronic device (<NUM>), wherein the electronic device comprises a frame and an antenna structure (<NUM>), the frame (<NUM>) comprises at least a bottom frame (<NUM>) and a first side frame (<NUM>), wherein one end of the bottom frame is connected to the first side frame; a first slot (<NUM>) and a third slot (<NUM>) are provided in the bottom frame, a distance from the first slot to the first side frame is smaller than a distance from the third slot to the first side frame; a second slot (<NUM>) is provided in the first side frame;
the antenna structure comprises a first radiation part (F1), a first connection part (<NUM>) and a first feed-in part (<NUM>), wherein a part of the frame between the first slot and the second slot forms the first radiation part; the first connection part is located on the first radiation part and located on the first side frame; the first feed-in part is located on the first radiation part; wherein
the antenna structure is configured to simultaneously generate a first resonance and a second resonance when a first signal is fed into the first radiation part via the first feed-in part;
a part of the frame between the first slot and the third slot is configured to form a first parasitic stub (F3) of the first radiation part; and
the antenna structure is configured to generate a third resonance based on the first parasitic stub when the first signal is fed into the first radiation part via the first feed-in part;
and wherein the third resonance is different from the first resonance and the second resonance.