This application claims priority to Chinese Patent Application No. 201911192854.3, filed with the China National Intellectual Property Administration on Nov. 28, 2019 and entitled “LOW-SAR WIDEBAND ANTENNA DESIGN WITH EQUIVALENT PERFORMANCE IN CASES OF LEFT HAND GRIP AND RIGHT HAND GRIP” and Chinese Patent Application No. 202010075891.2, filed with the China National Intellectual Property Administration on Jan. 22, 2020 and entitled “ANTENNA APPARATUS AND ELECTRONIC DEVICE”, which are incorporated herein by reference in their entireties.
The present invention relates to the field of antenna technologies, and in particular, to an antenna apparatus applied to an electronic device.
A multiple-input multiple-output (multi-input multi-output, MIMO) technology plays a very important role in a 5th generation (5th generation, 5G) wireless communications system. However, it is still a big challenge that an electronic device, for example, a mobile phone, obtains good MIMO performance. One reason is that the very limited space inside the electronic device limits a frequency band that can be covered by a MIMO antenna and high performance.
In addition, with development of the mobile internet, there are more user use scenes of the electronic device, for example, a call scene, a landscape/portrait game scene, a landscape video and audio scene, and a portrait internet surfing scene. In different user use scenes, a posture in which a user grips the electronic device, for example, the mobile phone changes. It is also an important problem of equalizing antenna performance in cases of a left hand grip and a right hand grip in different user use scenes.
Embodiments of the present invention provide an antenna apparatus, to implement a wideband antenna design in which two resonant modes of a slot antenna are both a common mode. There is a same radiation pattern, performance in a case of a left hand grip and performance in a case of a right hand grip are equivalent, and SAR values in the two modes are close.
According to a first aspect, an embodiment of this application provides an electronic device. The electronic device includes a PCB, a metal frame, and an antenna apparatus. The antenna apparatus may include a slot, a first feeding point, a second feeding point, and a bridge structure.
The slot may be disposed between the PCB and a first section of the metal frame. Two ends of the slot may be grounded. The slot may include a first side edge and a second side edge, the first side edge may consist of one side edge of the PCB, and the second side edge may consist of the first section of the metal frame. A slit may be disposed on the second side edge. The second side edge may include a first part and a second part, the first part may be located on one side of the slit, and the second part may be located on the other side of the slit.
The first feeding point may be located on the first part of the second side edge, and the second feeding point may be located on the second part of the second side edge. The first feeding point may be connected to a positive electrode of a feeding source of the antenna apparatus, and the second feeding point may be connected to a negative electrode of the feeding source of the antenna apparatus.
The bridge structure may include a first end and a second end, the first end may be connected to the first part or extend to the slot over the first side edge, and the second end may be connected to the second part or extend to the slot over the first side edge.
In the first aspect, a feeding structure including the first feeding point and the second feeding point may excite the slot to generate a CM slot antenna mode. Such a feeding structure is anti-symmetrical feeding in the following embodiments. A current and an electric field in the CM slot antenna mode are distributed with the following features: The current is distributed in a same direction on two sides of the slit, but the electric field is distributed in opposite directions on the two sides of the slit. The current and the electric field in the CM slot antenna mode may be generated when parts of the slot that are on the two sides of the slit separately operate in a ¼ wavelength mode.
In comparison with a slot antenna in a conventional feeding manner, in an antenna design solution used for the electronic device provided in the first aspect, efficiency in a case of a left hand grip and efficiency in a case of a right hand grip may be basically the same in a portrait-mode grip scenario.
With reference to the first aspect, in some embodiments, the first feeding point and the second feeding point may be connected to a feeding network of the feeding source, and the feeding network may include two symmetrical parallel conducting wires that are formed by hollowing out a ground plane of the PCB and that extend from the ground plane.
With reference to the first aspect, in some embodiments, the bridge structure may be a metal support of a laser direct structure LDS, and may be mounted on a back side of a PCB 17. The bridge structure may be used to optimize impedance matching. In two sides of the PCB 17, a side on which the ground plane of the PCB is disposed may be referred to as a front side of the PCB, and the other side (on which no ground plane of a PCB is disposed) may be referred to as a back side of the PCB.
With reference to the first aspect, in some embodiments, the slit may be disposed at a middle location of the second side edge, or may be disposed away from the middle location.
With reference to the first aspect, in some embodiments, the slot may be a U-shaped slot. For example, the slot may extend from a bottom edge of the metal frame to two side edges of the metal frame, and may be a U-shaped slot located at a bottom of the electronic device. Similarly, the slot may alternatively be a U-shaped slot located at a top of the electronic device, or a U-shaped slot on a side edge of the electronic device.
With reference to the first aspect, in some embodiments, the slot may be an L-shaped slot. For example, the slot may extend from a bottom edge of the metal frame to one side edge of the metal frame, and may be an L-shaped slot located on a left side or a right side of a bottom of the electronic device. Similarly, the slot may alternatively be an L-shaped slot located at a top of the electronic device.
With reference to the first aspect, in some embodiments, an arrangement location of the antenna apparatus in the electronic device may be one or more of the following: a bottom of the electronic device, a top of the electronic device, or a side edge of the electronic device.
With reference to the first aspect, in some embodiments, the electronic device may include a plurality of antenna apparatuses, and the plurality of antenna apparatuses may be arranged at a plurality of locations at the top, at the bottom, or on the side edge of the electronic device. For example, if the electronic device includes two antenna apparatuses, the two antenna apparatuses may be respectively arranged at the top and the bottom of the electronic device.
With reference to the first aspect, in some embodiments, the first feeding point and the second feeding point may be respectively connected to the positive electrode and the negative electrode of the feeding source by using a coaxial transmission line, the first feeding point is specifically connected to an inner conductor of the coaxial transmission line, and the second feeding point is specifically connected to an outer conductor of the coaxial transmission line.
With reference to the first aspect, in some embodiments, the first feeding point and the second feeding point may be disposed close to the slit, or may be respectively disposed close to the two ends of the slot.
With reference to the first aspect, in some embodiments, a size of the bridge structure is large, and some lumped components (for example, a lumped inductor) may be added to reduce the size. In other words, a part of the bridge structure is a lumped component.
With reference to the first aspect, in some embodiments, the bridge structure is not limited to the LDS metal support mounted on the back side of the PCB. Alternatively, the bridge structure may be formed by hollowing out the ground plane of the PCB.
According to a second aspect, an embodiment of this application provides an electronic device. The electronic device includes a PCB, a metal frame, and an antenna apparatus. The antenna apparatus may include a slot, a first feeding point, a second feeding point, and a bridge structure.
The slot may be disposed between the PCB and a first section of the metal frame, the first section of the metal frame includes a first end and a second end, and two ends of the slot may be grounded. The slot may include a first side edge and a second side edge, the first side edge may consist of one side edge of the PCB, and the second side edge may consist of the first section of the metal frame. A plurality of slits may be disposed on the second side edge. The second side edge may include a first part, a second part, and a third part, the first part may be located on one side of the third part, and the second part may be located on the other side of the third part. The third part may include a first slit, a second slit, and a floating section located between the first slit and the second slit.
The first feeding point may be located on the first part of the second side edge, and the second feeding point may be located on the second part of the second side edge. The first feeding point may be connected to a positive electrode of a feeding source of the antenna apparatus, and the second feeding point may be connected to a negative electrode of the feeding source of the antenna apparatus.
The bridge structure may include a first end and a second end, the first end may be connected to the first part or extend to the slot over the first side edge, and the second end may be connected to the second part or extend to the slot over the first side edge.
It can be learned that, a difference between the second aspect and the first aspect is that there are two slits, the first slit and the second slit on the second side edge in the second aspect. There may be more than two slits. The third part may include three or more slits and a floating section between these slits.
With reference to the second aspect, in some embodiments, the bridge structure may be further connected to the floating section in the third part.
With reference to the second aspect, in some embodiments, the bridge structure may include a T-shaped structure: The bridge structure is connected to a floating metal frame between the slits in addition to parts of the slot that are on two sides of the slits. Specifically, the T-shaped structure may include a transverse branch and a vertical branch, two ends of the transverse branch are respectively the first end and the second end, and are respectively connected to the first part of the second side edge and the second part of the second side edge, and the vertical branch is connected to the floating section.
With reference to the second aspect, in some embodiments, the bridge structure may be a metal support of a laser direct structure LDS, and may be mounted on a back side of the PCB. The bridge structure may be used to optimize impedance matching. In two sides of the PCB, a side on which a ground plane of the PCB is disposed may be referred to as a front side of the PCB, and the other side (on which no ground plane of a PCB is disposed) may be referred to as a back side of the PCB.
With reference to the second aspect, in some embodiments, the slit may be disposed at a middle location of the second side edge, or may be disposed away from the middle location.
With reference to the second aspect, in some embodiments, the slot may be a U-shaped slot. For example, the slot may extend from a bottom edge of the metal frame to two side edges of the metal frame, and may be a U-shaped slot located at a bottom of the electronic device. Similarly, the slot may alternatively be a U-shaped slot located at a top of the electronic device, or a U-shaped slot on a side edge of the electronic device.
With reference to the second aspect, in some embodiments, the slot may be an L-shaped slot. For example, the slot may extend from a bottom edge of the metal frame to one side edge of the metal frame, and may be an L-shaped slot located on a left side or a right side of a bottom of the electronic device. Similarly, the slot may alternatively be an L-shaped slot located at a top of the electronic device.
With reference to the second aspect, in some embodiments, an arrangement location of the antenna apparatus in the electronic device may be one or more of the following: a bottom of the electronic device, a top of the electronic device, or a side edge of the electronic device.
With reference to the second aspect, in some embodiments, the electronic device may include a plurality of antenna apparatuses, and the plurality of antenna apparatuses may be arranged at a plurality of locations at the top, at the bottom, or on the side edge of the electronic device. For example, if the electronic device includes two antenna apparatuses, the two antenna apparatuses may be respectively arranged at the top and the bottom of the electronic device.
With reference to the second aspect, in some embodiments, the first feeding point and the second feeding point may be respectively connected to the positive electrode and the negative electrode of the feeding source by using a coaxial transmission line, the first feeding point is specifically connected to an inner conductor of the coaxial transmission line, and the second feeding point is specifically connected to an outer conductor of the coaxial transmission line.
With reference to the second aspect, in some embodiments, the first feeding point and the second feeding point may be disposed close to the slit, or may be respectively disposed close to the two ends of the slot.
With reference to the second aspect, in some embodiments, a size of the bridge structure is large, and some lumped components (for example, a lumped inductor) may be added to reduce the size. In other words, a part of the bridge structure is a lumped component.
With reference to the second aspect, in some embodiments, the bridge structure is not limited to the LDS metal support mounted on the back side of the PCB. Alternatively, the bridge structure may be formed by hollowing out the ground plane of the PCB.
To describe technical solutions in embodiments of this application more clearly, the following describes accompanying drawings used in embodiments of this application.
The following describes embodiments of the present invention with reference to the accompanying drawings in embodiments of the present invention.
The technical solutions provided in this application are applicable to an electronic device that uses 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 5G communications technology, a SUB-6G communications technology, and other future communications technologies. In this application, the electronic device may be a mobile phone, a tablet computer, a personal digital assistant (personal digital assistant, PDA), or the like.
The glass cover 13 may be disposed closely in contact with the display 15, and may be mainly configured to protect the display 15 against dust.
The printed circuit board PCB 17 may be an FR-4 dielectric board, or may be a Rogers (Rogers) dielectric board, or may be a dielectric board mixing Rogers and FR-4, or the like. Herein, FR-4 is a grade designation for a flame-resistant material, and the Rogers dielectric board is a high-frequency board. A metal layer may be disposed on a side that is of the printed circuit board PCB 17 and that is close to the housing 19, and the metal layer may be formed by etching metal on a surface of the PCB 17. The metal layer may be used for grounding an electronic component carried on the printed circuit board PCB 17, to prevent a user from an electric shock or prevent a device from being damaged. The metal layer may be referred to as a ground plane of the PCB. In this application, in two sides of the PCB 17, a side on which the ground plane of the PCB is disposed may be referred to as a front side (front side) of the PCB, and the other side (on which no ground plane of a PCB is disposed) may be referred to as a back side (back side) of the PCB.
The housing 19 mainly supports the entire electronic device. The housing 19 may include a metal frame 11, and the metal frame 11 may be made of a conductive material such as metal. The metal frame 11 may extend around a periphery of the PCB 17 and the display 15, to help fasten the display 15. In an implementation, the metal frame 11 made of the metal material may be directly used as a metal frame of the electronic device 10, form an appearance of the metal frame, and is applicable to a metal ID. In another implementation, a non-metal frame, for example, a plastic frame, may alternatively be disposed on an outer surface of the metal frame 11, form an appearance of the non-metal frame, and is applicable to a non-metal ID.
The metal frame 11 may be divided into four parts, and the four parts may be named as a bottom edge, a top edge, and two side edges based on different locations of the four parts in the electronic device. The top edge may be disposed at a top of the electronic device 10, and the bottom edge may be disposed at a bottom of the electronic device 10. The two side edges may be respectively disposed on two sides of the electronic device 10. Components such as a front-facing camera (not shown), an earpiece (not shown), and an optical proximity sensor (not shown) may be disposed at the top of the electronic device 10. A USB charging interface (not shown), a microphone (not shown), and the like may be disposed at the bottom of the electronic device 10. A volume adjustment button (not shown) and a power button (not shown) may be disposed at the lateral sides of the electronic device 10.
The rear cover 21 may be a rear cover made of a non-metal material, for example, a non-metal rear cover such as a glass rear cover or a plastic rear cover, or may be a rear cover made of a metal material.
To bring a more comfortable visual feeling to the user, a full-screen industrial design (industrial design. ID) may be used for the electronic device 10. The bezel-less screen means a large screen-to-body ratio (usually over 90%). A width of a frame of a full screen is greatly reduced, and internal components of the electronic device 10 such as a front-facing camera, a telephone receiver, a fingerprint sensor, and an antenna need to be re-arranged. Especially for an antenna design, a clearance area is reduced and antenna space is further compressed.
In the conventional technology, when antenna design space is further reduced, an antenna design solution shown in
As shown in
This application provides an antenna design solution. An anti-symmetrical feeding structure is used to implement a wideband antenna design in which two resonant modes of a slot antenna are both a common mode slot antenna mode. The two resonances have a same radiation pattern, and performance in a case of a left hand grip and performance in a case of a right hand grip are equivalent. In addition, specific absorption ratio (specific absorption ratio, SAR) values of the two modes are close.
First, two antenna modes are described in this application.
Common Mode (Common Mode, CM) Slot Antenna Mode
As shown in
In other words, the slot antenna 101 may be fed at the opening 105, and the opening 105 may also be referred to as a feeding location. The positive electrode of the feeding source may be connected to one side of the opening 105, and the negative electrode of the feeding source may be connected to the other side of the opening 105.
The current and the electric field in the CM slot antenna mode are generated when parts of the slot that are on the two sides of the middle location of the slot antenna 101 separately operate in a ¼ wavelength mode: The current is weak at the middle location of the slot antenna 101, and is strong at two ends of the slot antenna 101. The electric field is strong at the middle location of the slot antenna 101, and is weak at the two ends of the slot antenna 101.
Differential Mode (Differential Mode, DM) Slot Antenna Mode
As shown in
In other words, a middle location 112 of the slot antenna 110 is connected to the feeding source, and the middle location 112 may also be referred to as a feeding location. The positive electrode of the feeding source may be connected to one side edge of the slot 113, and the negative electrode of the feeding source may be connected to the other side edge of the slot 113.
The current and the electric field in the DM slot antenna mode are generated when the entire slot 21110 operates in a ½ wavelength mode: The current is weak at the middle location of the slot antenna 110, and is strong at two ends of the slot antenna 110. The electric field is strong at the middle location of the slot antenna 110, and is weak at the two ends of the slot antenna 110.
The following describes in detail a plurality of embodiments provided in this application with reference to the accompanying drawings. In the following embodiments, an antenna simulation is performed based on the following environment: a width of an entire electronic device is 78 mm, and a length of the entire electronic device is 158 mm. A thickness of a metal frame 11 is 4 mm, a width is 3 mm, and an antenna clearance of a Z-directed projection region is 1 mm. A width of a slit (for example, a slit 25) on the metal frame 11 ranges from 1 mm to 2 mm. A dielectric constant of a material filled in a slot (for example, a slot 21) formed between the metal frame 11 and a ground plane of a PCB, the slit 25 on the metal frame 11, and a gap between a bridge structure 29 and the ground plane of the PCB is 3.0, and a loss angle is 0.01.
In this embodiment, a metal frame 11 and a ground plane of a PCB form a slot antenna radiator, and two low frequency (an operating frequency band is near LTE B5) CM slot antenna modes of the slot antenna radiator are separately excited through anti-symmetrical feeding.
As shown in
The slot 21 may be disposed between the PCB 17 and a first section of the metal frame 11. One side edge 23-1 of the slot 21 includes one side edge 17-1 of the PCB 17, and the other side edge 23-2 includes the first section of the metal frame 11. The first section of the metal frame 11 may be a segment of the metal frame from a location 11-1 to a location 11-3. The side edge 23-1 may be referred to as a first side edge, and the side edge 23-2 may be referred to as a second side edge. The first section of the metal frame 11 may be specifically a bottom edge of the metal frame. In other words, the slot 21 may be disposed between the PCB 17 and the bottom edge of the metal frame. For example, as shown in
Two ends of the slot 21 may be grounded, and the two ends may include one end 21-1 and the other end 21-3.
A slit 25 may be disposed the side edge 23-2 that is of the slot 21 and that includes the metal frame 11. The slit 25 may connect the slot 21 and external free space. There may be one or more slits 25 on the side edge 23-2.
When there is one slit 25 on the side edge 23-2, the side edge 23-2 may include two parts: a first part and a second part. The first part is located on one side of the slit 25, and the second part is located on the other side of the slit 25.
When there are a plurality of slits 25 on the side edge 23-2, the plurality of slits 25 may divide the side edge 23-2, to form a floating section. Specifically, when there are a plurality of slits 25 on the side edge 23-2, the side edge 23-2 may include three parts: a first part, a second part, and a third part. The first part is located on one side of the third part, the second part is located on the other side of the third part, and the third part may include the plurality of slits 25 and a floating section between the plurality of slits 25. For example, when there are two slits 25 (which may be respectively referred to as a first slit and a second slit) on the side edge 23-2, the side edge 23-2 may include three parts: a first part, a second part and a third part, the first part is located on one side of the third part, the second part is located on the other side of the third part, and the third part may include the two slits 25 and a floating section between the two slits 25.
The slit 25 may be disposed at a middle location of the side edge, or may be disposed away from the middle location. If there are a plurality of slits 25, the slits 25 are disposed at the middle location of the side edge. That the slits 25 are disposed at the middle location of the side edge may mean that the plurality of slits are located at the middle location of the side edge 23-2 as a whole.
The feeding point M and the feeding point N may be located on the side edge 23-2 that is of the slot 21 and that includes the metal frame 11, and specifically, may be respectively disposed on two sides of the slit 25. In other words, the feeding point M is located on the first part of the side edge 23-2, and the feeding point N is located on the second part of the side edge 23-2.
The slot antenna provided in Embodiment 1 may be of an anti-symmetrical feeding structure. In other words, the feeding point M and the feeding point N may be respectively used to be connected to a positive electrode and a negative electrode of a feeding source. For example, the slot antenna may be fed by using a coaxial transmission line, an inner conductor (which is connected to the positive electrode of the feeding source) of the coaxial transmission line may be connected to the feeding point M through the transmission line, and an outer conductor (which is grounded) of the coaxial transmission line may be connected to the feeding point N through the transmission line. On the side edge 23-2 of the slot 21, the feeding point M and the feeding point N may be specifically symmetrically disposed on two sides of the middle location of the side edge 23-2.
As shown in
In addition, a matching network 28 of the feeding network can be further formed by hollowing out the PCB 17. Connection points between the matching network 28 and the feeding network are a connection point E, a connection point F, a connection point J, and a connection point K.
Such a feeding structure shown in
Further, the slot antenna provided in Embodiment 1 may further include a bridge structure 29. The bridge structure 29 may be a metal support of a laser direct structure (laser direct structuring, LDS), and may be mounted on the back side of the PCB 17. For example, as shown in
The two ends of the bridge structure 29 include a first end 26-2 and a second end 26-1. The first end 26-2 may be connected to the first part of the side edge 23-2, or extend to the slot over the first side edge, and the second end 26-1 may be connected to the second part of the side edge 23-2, or extend to the slot over the first side edge. When the slot 21 is a U-shaped slot extending to the side edge of the metal frame 11, the first end 26-2 and the second end 26-1 may be specifically connected to two side edges of the metal frame 11.
The bridge structure 29 is not limited to that shown in
A dimension of the slot antenna provided in Embodiment 1 may be as follows: A width of the slot 21 is 1 mm. A closed end (a negative electrode) of the slot 21 extends to two ends of the side edge of the metal frame 11, and a distance to the bottom edge of the metal frame 11 is 15 mm. Widths of two slits disposed at a bottom of the metal frame 11 are 1 mm, and a distance between the two slits is 8 mm. A distance between a left slit and a left side of the metal frame 11 is 34.5 mm, and a distance between a right slit and a right side of the metal frame 11 is 34.5 mm.
The following describes a simulation of the slot antenna provided in Embodiment 1 with reference to the accompanying drawings.
It can be learned from all simulation results shown in
In addition, Table 1 shows an SAR of the electronic device 10 for which the slot antenna provided in Embodiment 1 is used. Table 2 shows an SAR of the electronic device 10 for which the slot antenna shown in
Table 1 and Table 2 show an SAR in a standard of 10 g. It can be learned that when an output power is 24 dB, an entire SAR (an SAR of the back and an SAR of the bottom) of the electronic device 10 for which the slot antenna provided in Embodiment 1 is used is low. When efficiency is normalized to −5 dB, the slot antenna provided in Embodiment 1 has a more obvious advantage in a case of a low SAR. The SAR of the back is measured when a human tissue is 5 mm away from the back of the electronic device, and the SAR of the bottom is measured when the human tissue is 5 mm away from the bottom of the electronic device.
It can be learned that, in the antenna design solution provided in Embodiment 1, the metal frame 11 and the ground plane of the PCB form a slot antenna radiator, and two low frequency (an operating frequency band is near LTE B5) CM slot antenna modes of the slot antenna radiator are separately excited through symmetrical feeding. When dual resonances and wideband coverage are implemented, performance in a case of the left hand grip and performance in a case of the right hand grip are equivalent, and SAR values in the two modes are close.
For a slot antenna provided in this embodiment, two medium/high frequency (an operating frequency band is near 2.4 GHz Wi-Fi) CM slot antenna modes of the slot antenna may be separately excited through anti-symmetrical feeding.
As shown in
The slot 21 may be disposed between the PCB 17 and a first section of a metal frame 11. Different from that in Embodiment 1, the slot 21 in Embodiment 2 is shorter, to form a slot radiator with a smaller size, and generate a medium/high frequency resonance. A length of the slot 21 may be less than a first length (for example, 50 mm). For example, as shown in
A slit 25 may be disposed a side edge 23-2 that is of the slot 21 and that includes the metal frame 11. There may be one or more slits 25 on the side edge 23-2. For example, as shown in
The feeding point M and the feeding point N may be located on the side edge 23-2 that is of the slot 21 and that includes the metal frame 11, and specifically, may be respectively disposed on two sides of the slit 25. In other words, the feeding point M is located on a first part of the side edge 23-2, and the feeding point N is located on a second part of the side edge 23-2.
The same as that in Embodiment 1, the slot antenna provided in Embodiment 2 may further include a bridge structure 29. Different from that in Embodiment 1, the bridge structure 29 in Embodiment 2 may be a U-shaped structure, and two ends of the bridge structure 29 may be respectively connected to parts of the slot that are on the two sides of the slit 25. A first end 26-1 and a second end 26-2 of the bridge structure 29 may be specifically connected to a bottom edge of the metal frame 11.
In Embodiment 2, the anti-symmetrical feeding structure described in Embodiment 1 may be used. For details, refer to Embodiment 1. Details are not described herein again.
A dimension of the slot antenna provided in Embodiment 2 may be as follows: A width of the slot 21 is 1 mm. A width of one slit disposed at a bottom of the metal frame 11 is 2 mm, and lengths of parts of the slot radiator that are on two sides of the slit are both 22 mm.
The following describes a simulation of the slot antenna provided in Embodiment 2 with reference to the accompanying drawings.
It can be learned from all simulation results shown in
In addition, Table 3 shows an SAR of the electronic device 10 for which the slot antenna provided in Embodiment 2 is used. Table 4 shows an SAR of the electronic device 10 for which the slot antenna shown in
Table 3 and Table 4 show an SAR in a standard of 10 g. It can be learned that when an output power is 24 dB, an entire SAR (an SAR of the back and an SAR of the bottom) of the electronic device 10 for which the slot antenna provided in Embodiment 2 is used is low. When efficiency is normalized to −5 dB, the slot antenna provided in Embodiment 2 has a more obvious advantage in a case of a low SAR. The SAR of the back is measured when a human tissue is 5 mm away from the back of the electronic device, and the SAR of the bottom is measured when the human tissue is 5 mm away from the bottom of the electronic device.
It can be learned that, in the antenna design solution provided in Embodiment 2, two medium/high frequency (an operating frequency band is near 2.4 G3 Hz Wi-Fi) CM slot antenna modes of one short slot antenna radiator may be separately excited through symmetrical feeding and anti-symmetrical feeding. When dual resonances and wideband coverage are implemented, performance in a case of the left hand grip and performance in a case of the right hand grip are equivalent, and SAR values in the two modes are close.
In the foregoing embodiment, the feeding point M and the feeding point N may be respectively referred to as a first feeding point and a second feeding point.
In the foregoing embodiment, the feeding point M and the feeding point N are not limited to being disposed close to the slit, but the feeding point M and the feeding point N may alternatively be respectively disposed close to two ends of the slot 21, as shown in
In the feeding structure in the foregoing embodiment, the “bridge” structure (namely, the bridge structure 29) has a large size, and some lumped components (for example, a lumped inductor) may be added to reduce the size, as shown in
The slot antenna provided in the foregoing embodiment is not limited to being arranged at the bottom of the electronic device 10, but may alternatively be arranged at a top or on a side edge of the electronic device 10, as shown in
The antenna design solution provided in the foregoing embodiment is not limited to being implemented in an electronic device with a metal frame ID. The metal frame is merely a name. Another conductive structure surrounding the PCB 17, for example, a metal middle frame, may also be used as the metal frame in the foregoing embodiment. The slot 21 may alternatively include the metal middle frame and the PCB 17.
In an actual application, a structure of the electronic device usually cannot be completely symmetrical, and a connection location of a matching network, the “bridge” structure, or the like can be adjusted, to compensate for an imbalance of the structure.
In this application, a wavelength in a wavelength mode (for example, a half-wavelength mode or a quarter-wavelength mode) of an antenna may be a wavelength of a signal radiated by the antenna. For example, a half-wavelength mode of the antenna may generate a resonance on a frequency band of 2.4 GHz, and a wavelength in the half-wavelength mode is a wavelength at which the antenna radiates a signal on the frequency band of 2.4 GHz. It should be understood that a wavelength of a radiation signal in the air may be calculated as follows: Wavelength=Speed of light/Frequency, where the frequency is a frequency of the radiation signal. A wavelength of the radiation signal in a medium may be calculated as follows: Wavelength=(Speed of light/f)/Frequency. Herein, e is a relative dielectric constant of the medium, and the frequency is a frequency of the radiation signal.
The foregoing descriptions are merely specific implementations of this application, but are not intended to limit the protection scope of this application. Any variation or replacement readily figured out by a person skilled in the art within the technical scope disclosed in this application shall fall within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.
Number | Date | Country | Kind |
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201911192854.3 | Nov 2019 | CN | national |
202010075891.2 | Jan 2020 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2020/132206 | 11/27/2020 | WO |