CN114156633B

CN114156633B - Low SAR antenna device and electronic equipment

Info

Publication number: CN114156633B
Application number: CN202210117180.6A
Authority: CN
Inventors: 张澳芳; 魏鲲鹏; 胡义武; 褚少杰
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2022-02-08
Filing date: 2022-02-08
Publication date: 2022-07-05
Anticipated expiration: 2042-02-08
Also published as: CN114156633A

Abstract

The embodiment of the application provides a low SAR antenna device and electronic equipment, this low SAR antenna device is through setting up at least one auxiliary radiation unit, auxiliary radiation unit's one end links to each other with main radiation unit, auxiliary radiation unit's the other end links to each other with the feed source, the feed source is main radiation unit and auxiliary radiation unit feed respectively, and auxiliary radiation unit does not produce the resonance on main radiation unit's operating frequency, can reduce low SAR antenna device in the SAR value under the state apart from human 0mm, do not change low SAR antenna device radiation performance under free space, thereby can promote low SAR antenna device's radiating effect.

Description

Low SAR antenna device and electronic equipment

Technical Field

The embodiment of the application relates to the technical field of antennas, in particular to a low SAR antenna device and electronic equipment.

Background

With the continuous development of communication technology, the wireless performance of electronic devices such as mobile phones and the like receives more and more attention, and thus, the application of antenna technology to electronic devices is increasingly wide and the demand is also increasingly high. However, when a human body part is close to the antenna, the antenna radiates to the human body.

Specific Absorption Rate (SAR) can be used to represent the amount of radiation emitted by the antenna to the human body. At present, the size of the radiation of the antenna to the human body is generally measured by an SAR value of a human body close to the electronic equipment by 5mm or 0mm, wherein the SAR value in a 0mm state is higher than that in a 5mm state, and the radiation to the human body is larger. Generally, when the transmission power of the antenna is high, the radiation generated to the human body is high, and when the transmission power of the antenna is low, the radiation generated to the human body is low, but the signal is poor. In the related art, in order to reduce the SAR value of the antenna and change the radiation performance of the antenna in the free space, it is an extremely important problem to be solved in the antenna field that how to reduce the SAR value of the antenna in the state of being 0mm away from the human body without changing the radiation performance of the antenna in the free space.

Disclosure of Invention

The embodiment of the application provides a low SAR antenna device and electronic equipment, can reduce the SAR value of the low SAR antenna device in the state of 0mm away from the human body, and simultaneously does not change the radiation performance of the low SAR antenna device in the free space, thereby improving the radiation effect of the low SAR antenna device.

In a first aspect, an embodiment of the present application provides a low SAR antenna apparatus, where the low SAR antenna apparatus is applied to an electronic device, and the low SAR antenna apparatus at least includes: at least one main radiating element and at least one feed; further comprising: one end of the auxiliary radiating unit is connected with the main radiating unit, and the other end of the auxiliary radiating unit is connected with the power feed; the feeding source feeds power to the main radiating element and the auxiliary radiating element respectively, and the auxiliary radiating element does not generate resonance on the working frequency of the main radiating element.

The low SAR antenna device provided by the embodiment of the application is characterized in that at least one auxiliary radiation unit is arranged, one end of the auxiliary radiation unit is connected with the main radiation unit, the other end of the auxiliary radiation unit is connected with a feed source, so that at least one feeding source feeds at least one main radiating element and one auxiliary radiating element respectively, in addition, because the auxiliary radiating element does not generate resonance on the working frequency of the main radiating element, the low SAR antenna device is in a free space state, when the main radiating unit works in a resonance state, the resonance frequency of the auxiliary radiating unit is far away from the working frequency of the main radiating unit, that is, the secondary radiating element operates in a non-resonant state, in which most of the energy of the low SAR antenna device is radiated from the main radiating element, the radiation energy ratio of the secondary radiating element is small, and thus the influence of the secondary radiating element on the performance of the main radiating element is extremely small. When the main radiation unit is close to a human body, part of energy of the main radiation unit can be reflected back by the human body, and part of energy of the main radiation unit is reflected and absorbed by the human body, so that the radiation energy proportion of the main radiation unit is greatly weakened, the radiation energy proportion of the auxiliary radiation unit is greatly enhanced, and the reduction of the SAR value of the main radiation unit of 0mm can be realized. Therefore, the SAR value of the low SAR antenna device in a state of being 0mm away from a human body can be reduced, and meanwhile, the radiation performance of the low SAR antenna device in a free space is not changed, so that the radiation effect of the low SAR antenna device can be improved.

In one possible implementation, the resonant frequency of the secondary radiating element is 1 to 3 times the resonant frequency of the primary radiating element. When the resonant frequency of the auxiliary radiating element is too low, the free space state of the low-SAR antenna device is affected, and when the resonant frequency of the auxiliary radiating element is too high, the radiating capability of the auxiliary radiating element is low, so that the radiating effect of the low-SAR antenna device is poor. When the resonant frequency of the auxiliary radiating element is 1 to 3 times of the resonant frequency of the main radiating element, the free space state of the low SAR antenna device is not influenced, and the radiation effect of the low SAR antenna device can be ensured.

In one possible implementation manner, the method further includes: a first transmission line and a second transmission line; the number of the secondary radiating elements is one; one end of the first transmission line is connected with the main radiating unit, and the other end of the first transmission line is connected with the auxiliary radiating unit; one end of the second transmission line is connected with the auxiliary radiating unit, and the other end of the second transmission line is connected with the power supply. When the number of the auxiliary radiating elements is one, one end of each auxiliary radiating element can be connected with the main radiating element, and the other end of each auxiliary radiating element is connected with the feeding source, so that the feeding source can be used for respectively feeding the main radiating element and the auxiliary radiating elements in series.

In one possible implementation, the length of the first transmission line is between 1/8 and 1 wavelength of the first transmission line. When the main radiating unit is close to a human body, the radiation energy ratio of the main radiating unit is greatly weakened, and the auxiliary radiating unit is positioned near the maximum point of standing wave current of the first transmission line and the second transmission line, so that the radiation capability of the auxiliary radiating unit can be greatly enhanced. The length of the first transmission line is between 1/8 and 1 times of the wavelength of the first transmission line, so that the auxiliary radiating element is positioned near the maximum point of the standing wave current of the first transmission line and the second transmission line.

In one possible implementation, the length of the first transmission line is between 1/8 and 1/2 wavelengths of the first transmission line. The length of the first transmission line is between 1/8 and 1/2 wavelengths of the first transmission line, the range of the secondary radiating element when the secondary radiating element is positioned near the maximum point of standing wave current of the first transmission line and the second transmission line can be shortened, and the radiating capacity of the secondary radiating element can be further improved.

In one possible implementation manner, the method further includes: a matching circuit; one end of the matching circuit is connected with the main radiating unit, and the other end of the matching circuit is connected with the first transmission line. By arranging the matching circuit in the low-SAR antenna device, the realizable function of the low-SAR antenna device can be increased, and further the realizable function of the electronic equipment with the low-SAR antenna device can be increased.

In one possible implementation, the matching circuit includes at least: any one or more of a capacitor, inductor or resistor.

In one possible implementation manner, the method further includes: a third transmission line between the first transmission line and the second transmission line; the number of the secondary radiation units is two; one end of one of the two auxiliary radiating elements is connected with the first transmission line, and the other end of one of the two auxiliary radiating elements is connected with the third transmission line; one end of the other of the two auxiliary radiating elements is connected with the third transmission line, and the other end of the other of the two auxiliary radiating elements is connected with the second transmission line.

When the number of the auxiliary radiating elements is two, the two auxiliary radiating elements can be ensured to be connected in series, one of the two auxiliary radiating elements is connected with the main radiating element, and the other of the two auxiliary radiating elements is connected with the feeding source, so that the feeding source can be ensured to be capable of respectively feeding the main radiating element and the two auxiliary radiating elements in series at the same time.

In one possible implementation manner, the method further includes: a fourth transmission line and a fifth transmission line; the number of the auxiliary radiation units is two; one end of the fourth transmission line is connected with the main radiating element, and the other end of the fourth transmission line is connected with one end of one of the two auxiliary radiating elements; one end of the fifth transmission line is connected with the other end of one of the two auxiliary radiating units, and the other end of the fifth transmission line is connected with the power supply; one end of the other of the two auxiliary radiating elements is connected with the first transmission line, and the other end of the other of the two auxiliary radiating elements is connected with the second transmission line.

When the number of the auxiliary radiating elements is two, the two auxiliary radiating elements can be ensured to be connected in parallel, one of the two auxiliary radiating elements is respectively connected with the main radiating element and the feed source, and the other of the two auxiliary radiating elements is respectively connected with the main radiating element and the feed source, so that the feed source can be ensured to feed the main radiating element and the two auxiliary radiating elements simultaneously and respectively.

In a second aspect, an embodiment of the present application provides an electronic device, which at least includes: display screen, backshell and be located the display screen with the center between the backshell still includes: the low SAR antenna device of any of the above; the middle frame is a metal middle frame, the metal middle frame at least comprises a metal frame, and the metal frame forms at least one main radiation unit in the low SAR antenna device.

The electronic device provided by the embodiment of the application at least comprises a low-SAR antenna device, wherein the low-SAR antenna device is provided with at least one auxiliary radiating element, one end of the auxiliary radiating element is connected with the main radiating element, the other end of the auxiliary radiating element is connected with a feeding source, so that at least one feeding source respectively feeds power to the at least one main radiating element and the auxiliary radiating element, and in addition, the auxiliary radiating element does not generate resonance on the working frequency of the main radiating element, so that when the low-SAR antenna device is in a free space state and the main radiating element works in a resonance state, the resonance frequency of the auxiliary radiating element is far away from the working frequency of the main radiating element, namely the auxiliary radiating element works in a non-resonance state, at the moment, most energy of the low-SAR antenna device is radiated by the main radiating element, and the radiation energy of the auxiliary radiating element occupies a small proportion, the effect of the secondary radiating element on the performance of the primary radiating element is extremely small. When the main radiation unit is close to a human body, part of energy of the main radiation unit is reflected by the human body, and part of energy of the main radiation unit is reflected and absorbed by the human body, so that the radiation energy proportion of the main radiation unit is greatly reduced, the radiation energy proportion of the auxiliary radiation unit is greatly enhanced, and the reduction of the SAR value of the main radiation unit of 0mm can be realized. Therefore, the SAR value of the low SAR antenna device in a state of being 0mm away from a human body can be reduced, and meanwhile, the radiation performance of the low SAR antenna device in a free space is not changed, so that the radiation effect of the low SAR antenna device can be improved.

In one possible implementation, the secondary radiating element in the low SAR antenna device is a metal sheet.

In one possible implementation, the metal middle frame further includes: a metal middle plate; the metal frame is arranged around the periphery of the metal middle plate; and the vertical distance between the auxiliary radiation unit of the low SAR antenna device and the metal middle plate is 0.5mm-3 mm. Therefore, the radiation performance of the auxiliary radiation unit can be ensured while the auxiliary radiation unit of the low SAR antenna device is suspended.

Drawings

Fig. 1 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

FIG. 2 is an exploded view of FIG. 1;

fig. 3 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of the low SAR antenna apparatus in the electronic device shown in fig. 3;

fig. 5 is a partial schematic structural view of an antenna device in the prior art when the antenna device is matched with a middle frame;

fig. 6 is a schematic partial structural diagram of a low SAR antenna device according to an embodiment of the present application when being engaged with a middle frame;

fig. 7 is a schematic structural diagram of a low SAR antenna device according to an embodiment of the present application when approaching a human body;

fig. 8 is a schematic diagram illustrating an operating state of a low SAR antenna device according to an embodiment of the present application in a free space state;

fig. 9 is a schematic diagram illustrating an operating state of the low SAR antenna apparatus according to an embodiment of the present application when approaching a human body;

fig. 10 is a schematic structural diagram of a low SAR antenna apparatus according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of a low SAR antenna apparatus according to an embodiment of the present application;

fig. 12 is a graph comparing reflection coefficient curves of a low SAR antenna device according to an embodiment of the present application in a free space state compared to a prior art antenna device;

fig. 13 is a comparison graph of antenna efficiency curves of a low SAR antenna device according to an embodiment of the present application in a free space state as compared to an antenna device of the prior art;

fig. 14 is a radiation pattern at 2.45GHz for a prior art antenna apparatus in a free space state;

fig. 15 is a radiation pattern at 2.45GHz when the low SAR antenna apparatus provided by an embodiment of the present application is in a free space state;

fig. 16 is a graph comparing reflection coefficient curves of the low SAR antenna device according to an embodiment of the present application with those of the prior art in a state of 0mm of the human body;

fig. 17 is a comparison graph of antenna efficiency curves of the low SAR antenna device according to an embodiment of the present application in a state of 0mm of a human body compared to the antenna device in the prior art;

fig. 18 is a SAR hot spot diagram of the antenna device in the prior art in a state of 0mm of the human body;

fig. 19 is a SAR hotspot graph of the low SAR antenna device provided in the embodiment of the present application in a 0mm state of a human body.

Description of reference numerals:

100-low SAR antenna device; 110-a main radiating element; 120-a power feed;

130-a secondary radiating element; 140-a first transmission line; 150-a second transmission line;

160-matching circuit; 170-a third transmission line; 180-a fourth transmission line;

190-a fifth transmission line; 200-an electronic device; 210-a display screen;

211-a first opening; 220-middle frame; 221-metal middle plate;

222-a border; 2221-top border; 2222-bottom border;

2223-left side frame; 2224-right side frame; 230-a circuit board;

240-a battery; 250-a rear shell; 251-a second opening;

260-a front camera module; 270-rear camera module; 300-human body;

310-transmission line.

Detailed Description

The terminology used in the description of the embodiments of the present application is for the purpose of describing particular embodiments of the present application only and is not intended to be limiting of the application, as the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

The embodiment of the present application provides an electronic device, which may include, but is not limited to, a mobile or fixed terminal having an antenna, such as a mobile phone, a tablet computer, a notebook computer, an ultra-mobile personal computer (UMPC), a handheld computer, an intercom, a netbook, a Point of sale (POS) machine, a Personal Digital Assistant (PDA), a wearable device, a virtual reality device, a wireless usb disk, a bluetooth sound/earphone, or a vehicle-mounted front-end, a car recorder, and a security device.

Referring to fig. 1 and fig. 2, in the embodiment of the present application, a mobile phone is taken as an example to describe the electronic device, the mobile phone provided in the embodiment of the present application may be a curved-screen mobile phone or a flat-screen mobile phone, and in the embodiment of the present application, a flat-screen mobile phone is taken as an example to describe the electronic device. Fig. 1 and fig. 2 respectively show an overall structure and a split structure of a mobile phone, a display screen 210 of the mobile phone provided in the embodiment of the present application may be a water drop screen, a bang screen, a full screen, or a hole digging screen (see fig. 1), for example, a first opening 211 is formed in the display screen 210, and the following description takes the hole digging screen as an example for description.

Referring to fig. 2, the mobile phone may include: the display device comprises a display screen 210, a middle frame 220, a rear shell 250 and a battery 240 located between the middle frame 220 and the rear shell 250, wherein the battery 240 may be disposed on a side of the middle frame 220 facing the rear shell 250 (as shown in fig. 2), or the battery 240 may be disposed on a side of the middle frame 220 facing the display screen 210, for example, a side of the middle frame 220 facing the rear shell 250 may have a battery compartment (not shown), and the battery 240 is installed in the battery compartment.

In some other examples, the mobile phone may further include a circuit board 230, wherein the circuit board 230 may be disposed on the middle frame 220, for example, the circuit board 230 may be disposed on a side of the middle frame 220 facing the rear shell 250 (as shown in fig. 2), or the circuit board 230 may be disposed on a side of the middle frame 220 facing the display screen 210, and the display screen 210 and the rear shell 250 are respectively located on two sides of the middle frame 220.

The battery 240 may be connected to the charging management module and the circuit board 230 through a power management module, and the power management module receives input of the battery 240 and/or the charging management module and supplies power to the processor, the internal memory, the external memory, the display screen 210, the camera module (for example, the front camera module 260 and the rear camera module 270 in fig. 2), the communication module, and the like. The power management module may also be used to monitor parameters such as battery 240 capacity, battery 240 cycle count, battery 240 state of health (leakage, impedance), etc. In other embodiments, the power management module may also be disposed in the processor of the circuit board 230. In other embodiments, the power management module and the charging management module may be disposed in the same device.

When the mobile phone is a flat-panel mobile phone, the Display screen 210 may be an Organic Light-Emitting Diode (OLED) Display screen or a Liquid Crystal Display (LCD) Display screen, and when the mobile phone is a curved-panel mobile phone, the Display screen 210 may be an OLED Display screen.

With continued reference to fig. 2, the middle frame 220 may include a metal middle plate 221 and a frame 222, wherein the frame 222 is disposed around the outer circumference of the metal middle plate 221. In general, bezel 222 may include a top bezel 2221, a bottom bezel 2222, a left bezel 2223, and a right bezel 2224, wherein top bezel 2221, bottom bezel 2222, left bezel 2223, and right bezel 2224 enclose a bezel 222 in a square ring structure. The metal middle plate 221 is made of, but not limited to, an aluminum plate, an aluminum alloy, stainless steel, a steel-aluminum composite die-cast plate, a titanium alloy, or a magnesium alloy. The frame 222 may be a metal frame, a ceramic frame, or a glass frame. When the frame 222 is a metal frame, the material of the metal frame includes, but is not limited to, aluminum alloy, stainless steel, steel-aluminum composite die-cast plate, or titanium alloy. The middle metal plate 221 and the frame 222 may be clamped, welded, bonded or integrally formed, or the middle metal plate 221 and the frame 222 may be fixedly connected by injection molding.

Referring to fig. 2, the top frame 2221 and the bottom frame 2222 are disposed opposite to each other, the left frame 2223 and the right frame 2224 are disposed opposite to each other, the top frame 2221 is connected to one end of the left frame 2223 and one end of the right frame 2224 by a rounded corner, and the bottom frame 2222 is connected to the other end of the left frame 2223 and the other end of the right frame 2224 by a rounded corner, so as to form a rounded rectangular area. The rear housing is grounded and disposed in the rounded rectangular area, and is connected to the top frame 2221, the bottom frame 2222, the left frame 2223, and the right frame 2224, respectively. It will be appreciated that the back housing ground plane may be the back housing 250 of the handset.

The rear housing 250 may be a metal rear housing, a glass rear housing, a plastic rear housing, or a ceramic rear housing, and in the embodiment of the present application, the material of the rear housing 250 is not limited and is not limited to the above example.

It is noted that in some examples, the rear case 250 of the mobile phone may be connected to the bezel 222 to form an integrally formed (Unibody) rear case, for example, the mobile phone may include: the display screen 210, the metal middle plate 221 and the rear case, which may be a rear case formed by integrally molding (Unibody) the bezel 222 and the rear case 250, such that the circuit board 230 and the battery 240 are located in a space surrounded by the metal middle plate 221 and the rear case.

In addition, in a possible implementation manner, the rear case 250 may further be provided with a second opening 251 as a light-transmitting area of the rear camera module 270. Similarly, the first opening 211 on the display screen 210 can also be used as a light-transmitting area of the front camera module 260.

It should be noted that, in the embodiment of the present application, the electronic device may also be a tablet computer as shown in fig. 3. Specifically, referring to fig. 3, the tablet pc may include at least: a display screen 210 and a middle frame 220, wherein the middle frame 220 may include: metal middle plate 221 and frame 222, frame 222 sets up a circle around the periphery of metal middle plate 221.

It is to be understood that the illustrated structure of the embodiment of the present application does not specifically limit the electronic device 200. In other of the present embodiments, the electronic device 200 may include more or fewer components than shown, or combine certain components, or split certain components, or a different arrangement of components. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

In order to implement a communication function of the electronic device, an antenna may be provided on the electronic device to transmit and receive signals through the antenna. The antenna performance level of the electronic equipment in an actual use scene is directly related to the actual experience of a user. At present, most of electronic devices are designed by Industry (ID) of metal frames and glass backshells, and because the size of the metal frame is limited and the antenna environment is nervous, the antenna of some frequency bands can only excite a single mode of the metal frame to be miniaturized as much as possible, so that the performance of the antenna designed by the metal frame is greatly influenced by human body parts. Because the human body part belongs to the dielectric medium, when the human body parts such as head, hands and the like are close to the antenna, the antenna can radiate the human body. When the transmission power of the antenna is high, the radiation to the human body may be high, and when the transmission power of the antenna is low, the signal may be poor.

Specific Absorption Rate (SAR) can be used to represent the amount of radiation emitted by the antenna to the human body. Due to regulatory limitations on SAR values, the power of the antenna cannot be made very high. When the SAR value of the antenna is small, the transmitting power of the antenna can be higher, and the radiation to a human body is smaller, so that the quality of signals is improved.

At present, the size of the radiation of the antenna to the human body is generally measured by an SAR value of a human body close to the electronic equipment by 5mm or 0mm, wherein the SAR value in a 0mm state is higher than that in a 5mm state, and the radiation to the human body is larger. Generally, when the transmission power of the antenna is high, the radiation generated to the human body is high, and when the transmission power of the antenna is low, the radiation generated to the human body is low, but the signal is poor. In the related art, in order to reduce the SAR value of the antenna, the radiation performance of the antenna in the free space is also changed, and therefore, how to reduce the SAR value of the antenna in the state of being 0mm away from the human body without changing the radiation performance of the antenna in the free space is an extremely important problem to be solved in the antenna field.

Based on this, embodiments of the present application provide a new low SAR antenna device and an electronic device having the same, which can be applied to an electronic device (e.g., a mobile phone or a computer, etc.) to solve the above technical problems. This low SAR antenna device is through setting up at least one auxiliary radiation unit, auxiliary radiation unit's one end links to each other with main radiation unit, auxiliary radiation unit's the other end links to each other with the feed source, the feed source is main radiation unit and auxiliary radiation unit feed respectively, and auxiliary radiation unit's resonant frequency does not produce the resonance on main radiation unit's operating frequency, can be when reducing low SAR antenna device SAR value apart from human 0mm state, do not change the radiation performance of low SAR antenna device under free space, thereby can promote low SAR antenna device's radiation effect and radiation efficiency, and then and can promote user's result of use.

It should be noted that the low SAR antenna apparatus provided in the present application is suitable for an electronic device that employs any one or more communication technologies, such as Long Term Evolution (LTE) communication technology, Wi-Fi communication technology, 5G communication technology, SUB-6G communication technology, and other future communication technologies.

The specific structure of the low SAR antenna device will be described in detail below with reference to the specific drawings (the following embodiments do not highlight the requirement of the communication network, and only describe the operation characteristics of the low SAR antenna device in terms of frequency size).

Referring to fig. 4, an embodiment of the present application provides a low SAR antenna device 100, where the low SAR antenna device 100 is applied to an electronic device 200 (see fig. 3), and specifically, the low SAR antenna device 100 may include at least: at least one main radiating element 110, at least one feeding source 120 and at least one auxiliary radiating element 130, wherein one end of the auxiliary radiating element 130 is connected to the main radiating element 110, and the other end of the auxiliary radiating element 130 is connected to the feeding source 120, so that the feeding source 120 feeds power to the main radiating element 110 and the auxiliary radiating element 130, respectively.

It is to be understood that the present embodiment does not limit the antenna form of the main radiating element 110, for example, the main radiating element 110 may be a monopole antenna, an inverted antenna, or a loop antenna.

Compared with the antenna device in the prior art as shown in fig. 5, the low SAR antenna device 100 provided in the embodiment of the present application has the additional sub-radiating element 130 (see fig. 6 and 7), specifically, the sub-radiating element 130 is connected in series between the main radiating element 110 and the feeding source 120, and the sub-radiating element 130 does not generate resonance at the operating frequency of the main radiating element 110.

Since the sub-radiating element 130 does not resonate at the operating frequency of the main radiating element 110, when the main radiating element 110 operates in a resonant state in the free space state of the low SAR antenna device 100, the resonant frequency of the sub-radiating element 130 is far from the operating frequency of the main radiating element 110, that is, the sub-radiating element 130 operates in a non-resonant state. Fig. 8 is an antenna energy ratio diagram of the low SAR antenna device 100 provided in the embodiment of the present application in a free space state. At this time, as shown in fig. 8, most of the energy of the low SAR antenna device 100 is radiated from the main radiation unit 110, the radiation energy ratio of the sub radiation unit 130 is small, and thus the influence of the sub radiation unit 130 on the performance of the main radiation unit 110 is extremely small.

When the main radiation unit 110 is close to the human body 300 (see fig. 7), a part of the energy of the main radiation unit 110 is reflected by the human body 300, and a part of the energy is absorbed by the human body 300 because a part of the energy of the main radiation unit 110 is reflected. Fig. 9 is an antenna energy ratio schematic diagram of the low SAR antenna device 100 according to the embodiment of the present application in a state of 0mm of a human body. At this time, as shown in fig. 9, the radiation energy ratio of the main radiation unit 110 is much reduced, and the radiation energy ratio of the sub-radiation unit 130 is relatively greatly increased, so that the 0mm SAR value of the main radiation unit 110 can be reduced. Therefore, according to the embodiment of the application, while the SAR value of the low-SAR antenna device 100 in a state of being 0mm away from the human body 300 is reduced, the radiation performance of the low-SAR antenna device 100 in a free space is not changed, so that the radiation effect of the low-SAR antenna device 100 can be improved.

It should be noted that, in the embodiment of the present application, the middle frame 220 of the electronic device 200 may be a metal middle frame, where the metal middle frame may at least include a metal bezel, and the metal bezel may form a metal bezel antenna, and the metal bezel antenna serves as the at least one main radiation unit 110 in the low SAR antenna apparatus 100.

Specifically, the metal frame antenna may be the main radiation unit 110 located on the metal frame, and the main radiation unit 110 is formed by opening a slot on the metal frame, in other words, the metal frame antenna is a slot antenna formed by opening a slot on the metal frame. The slot antenna may include a first portion, a second portion, and a third portion separated by a gap, wherein a non-conductive material may be filled between the first portion and the second portion, between the second portion and the third portion, and between the third portion and the first portion. In this way, the main radiation element 110 may be a metal radiator formed by breaking two broken seams through a metal frame of the electronic device 200.

In practical applications, the positions of the gaps may be changed as required, and a non-conductive material (e.g., plastic) may be filled in each gap to ensure the integrity of the metal frame in appearance. Through setting up the position in the gap on the nimble metal frame that sets up, can realize the appearance design of different demands when guaranteeing antenna radiation performance, be favorable to promoting electronic equipment 200's product quality.

In addition, it is understood that the feeding point and the grounding point of the feeding source 120 may be electrically connected to the metal middle plate 221 as a floor in the electronic device 200, respectively.

In the embodiment of the present application, the resonance frequency of the secondary radiating element 130 may be greater than the resonance frequency of the primary radiating element 110. That is, the sub-radiating element 130 operates in a non-resonant state, and its resonant frequency is much higher than the operating frequency of the main radiating element 110.

Specifically, the resonance frequency of the sub radiating element 130 may be 1 to 3 times the resonance frequency of the main radiating element 110. When the resonant frequency of the sub-radiating element 130 is too low, the free space state of the low SAR antenna apparatus 100 may be affected, and when the resonant frequency of the sub-radiating element 130 is too high, the radiation capability of the sub-radiating element 130 is small, so that the radiation effect of the low SAR antenna apparatus 100 is poor. When the resonance frequency of the sub-radiating element 130 is 1 to 3 times the resonance frequency of the main radiating element 110, the radiation effect of the low SAR antenna device 100 can be ensured without affecting the free space state of the low SAR antenna device 100.

Referring to fig. 4, the low SAR antenna device 100 may further include: the number of the auxiliary radiating elements 130 is one, one end of the first transmission line 140 is connected with the main radiating element 110, the other end of the first transmission line 140 is connected with the auxiliary radiating element 130, one end of the second transmission line 150 is connected with the auxiliary radiating element 130, and the other end of the second transmission line 150 is connected with the feed source 120. When the number of the sub-radiating elements 130 is one, it is ensured that one end of the sub-radiating element 130 is connected to the main radiating element 110 and the other end of the sub-radiating element 130 is connected to the feeding source 120, thereby ensuring that the feeding source 120 can feed the main radiating element 110 and the sub-radiating element 130 in series, respectively.

In the present embodiment, the length of the first transmission line 140 may be between 1/8 and 1 times the wavelength of the first transmission line 140. Wherein the wavelength (λ) is the wavelength of the electromagnetic wave in the medium of the first transmission line 140.

When the main radiating element 110 is close to the human body 300, the radiation energy ratio of the main radiating element 110 is greatly reduced, and the auxiliary radiating element 130 is located near the maximum point of the standing wave current of the first transmission line 140 and the second transmission line 150, so that the radiation capability of the auxiliary radiating element 130 can be greatly enhanced. The length of the first transmission line 140 is between 1/8 and 1 times the wavelength of the first transmission line 140, so that the sub-radiating element 130 is located near the maximum point of the standing wave current of the first transmission line 140 and the second transmission line 150.

Specifically, in some embodiments, the length of the first transmission line 140 may be between 1/8 wavelengths and 1/2 wavelengths of the first transmission line 140. The length of the first transmission line 140 is in a range between 1/8 wavelengths to 1/2 wavelengths of the first transmission line 140 when the sub radiating unit 130 is located near the maximum point of the standing wave current of the first transmission line 140 and the second transmission line 150 in the state of the human body, so that the radiating capability of the sub radiating unit 130 can be further improved.

For example, the length of the first transmission line 140 may be 1/8 wavelength, 1/7 wavelength, 1/6 wavelength, 1/5 wavelength, 1/4 wavelength, 1/3 wavelength, 1/2 wavelength, and the like of the first transmission line 140, and the embodiment of the present application does not limit this to this, and is not limited to the above example.

Therefore, compared to the antenna device in the prior art as shown in fig. 5, in which the main radiating element 110 and the feeding source 120 are directly connected through the transmission line 310, the embodiment of the present application adds one sub-radiating element 130 to the feeding transmission path between the main radiating element 110 and the feeding source 120, and at the same time, by utilizing the difference between the traveling wave and standing wave characteristics of the first transmission line 140 and the second transmission line 150, the sub-radiating element 130 only needs a small free space radiation energy ratio, so that the SAR value of the human body 300 can be greatly reduced when the distance from the low SAR antenna device 100 is 0mm, and the performance of the main radiating element 110 in the free space state is very slightly affected.

Specifically, in the low SAR antenna apparatus 100 in the free space state, the signals of the first transmission line 140 and the second transmission line 150 are in the traveling wave state. At this time, when the main radiating element 110 operates in the resonant state, the resonant frequency of the sub radiating element 130 is far from the operating frequency of the main radiating element 110, that is, the sub radiating element 130 operates in the non-resonant state. Most of the energy of the low SAR antenna device 100 is radiated from the main radiation unit 110, the radiation energy ratio of the sub radiation unit 130 is small, and thus the influence of the sub radiation unit 130 on the performance of the main radiation unit 110 is extremely small.

When the main radiating element 110 approaches the human body 300, a part of the energy of the main radiating element 110 is reflected by the human body 300, and a standing wave is formed on the first transmission line 140 and the second transmission line 150. Since a part of the energy of the main radiation unit 110 is reflected and a part of the energy is absorbed by the human body 300, the radiation energy of the main radiation unit 110 is much attenuated. The sub radiating unit 130 is located near the maximum point of the standing wave current on the first transmission line 140 and the second transmission line 150, so that the radiating capability of the sub radiating unit 130 is greatly enhanced. Since the energy ratio of the radiation of the main radiation unit 110 is decreased and the energy ratio of the sub radiation unit 130 is increased, a reduction in the SAR value of the main radiation unit of 0mm is achieved.

In addition, as shown in fig. 6 or fig. 7, the low SAR antenna device 100 may further include: and one end of the matching circuit 160 is connected to the main radiating element 110, and the other end of the matching circuit 160 is connected to the first transmission line 140. By providing the matching circuit 160 in the low SAR antenna device 100, the realizable functions of the low SAR antenna device 100 can be increased, and further, the realizable functions of the electronic apparatus 200 having the low SAR antenna device 100 can be increased.

In one possible implementation, the matching circuit 160 may include at least: any one or more of a capacitor, inductor or resistor. For example, the matching circuit 160 may include only one or more capacitors, only one or more inductors, only one or more resistors, one or more capacitors and one or more inductors, one or more capacitors and one or more resistors, one or more resistors and one or more inductors, and one or more capacitors, one or more inductors, and one or more resistors, and one or more capacitors, one or more inductors, and one or more inductors.

In addition, it is understood that, in the present embodiment, another low SAR antenna device 100 is provided, as shown in fig. 10 and 11, the low SAR antenna device 100 shown in fig. 10 and 11 is different from the low SAR antenna device 100 shown in fig. 4, in that the number of the sub-radiating elements 130 in the low SAR antenna device 100 may be two.

It should be noted that, in the embodiment of the present application, when the number of the secondary radiation units 130 in the low SAR antenna device 100 is two, the specific structure and connection manner in the low SAR antenna device 100 include, but are not limited to, the following two possible implementation manners:

one possible implementation is: referring to fig. 10, the low SAR antenna device 100 may include: and a third transmission line 170 positioned between the first transmission line 140 and the second transmission line 150, one end of one of the two sub radiating elements 130 is connected to the first transmission line 140, the other end of one of the two sub radiating elements 130 is connected to the third transmission line 170, one end of the other of the two sub radiating elements 130 is connected to the third transmission line 170, and the other end of the other of the two sub radiating elements 130 is connected to the second transmission line 150.

This ensures that the two sub-radiating elements 130 are connected in series, one of the two sub-radiating elements 130 is connected to the main radiating element 110, and the other of the two sub-radiating elements 130 is connected to the feeding source 120, thereby ensuring that the feeding source 120 can feed the main radiating element 110 and the two sub-radiating elements 130 simultaneously.

Another possible implementation is: referring to fig. 11, the low SAR antenna device 100 may include: a fourth transmission line 180 and a fifth transmission line 190, one end of the fourth transmission line 180 is connected to the main radiating element 110, the other end of the fourth transmission line 180 is connected to one end of one of the two sub-radiating elements 130, one end of the fifth transmission line 190 is connected to the other end of one of the two sub-radiating elements 130, the other end of the fifth transmission line 190 is connected to the feeding source 120, one end of the other of the two sub-radiating elements 130 is connected to the first transmission line 140, and the other end of the other of the two sub-radiating elements 130 is connected to the second transmission line 150.

Thus, it is ensured that the two sub-radiating elements 130 are connected in parallel, one of the two sub-radiating elements 130 is connected to the main radiating element 110 and the power supply 120, and the other of the two sub-radiating elements 130 is connected to the main radiating element 110 and the power supply 120, so as to ensure that the power supply 120 can simultaneously and respectively supply power to the main radiating element 110 and the two sub-radiating elements 130.

It should be noted that, in the embodiment of the present application, for the same main radiation element 110, any number of sub radiation elements 130 may be added to the feeding path between the main radiation element 110 and the feeding source 120, and the embodiment of the present application is not limited by this. For example, three or more sub-radiating elements 130 may be added on the feeding path between the main radiating element 110 and the feeding source 120.

In the embodiment of the present application, the secondary radiating element 130 in the low SAR antenna device 100 may be a metal patch. For example, the secondary radiating element 130 may be a metal patch made of copper, a metal patch made of silver, or a metal patch made of silver-plated material, which is not limited in the embodiments of the present application and is not limited to the above examples. In addition, the specific size of the secondary radiating element 130 may be determined according to the resonant frequency of the primary radiating element 110 in the practical application scenario.

In the embodiment of the present application, the vertical distance between the sub-radiating element 130 of the low SAR antenna device 100 and the middle plate of the metal may be 0.5mm to 3 mm. This ensures the radiation performance of the sub-radiating element 130 while ensuring the suspended arrangement of the sub-radiating element 130 of the low SAR antenna device 100.

For example, the vertical distance between the sub-radiating element 130 of the low SAR antenna device 100 and the metal middle plate may be 0.5mm, 1.0mm, 1.5mm, 2.0mm, 2.5mm, or 3mm, and the like, which is not limited by the embodiments of the present application. It should be noted that the numerical values and numerical ranges related to the embodiments of the present application are approximate values, and there may be a certain range of errors depending on the manufacturing process, and the error may be considered as negligible by those skilled in the art.

Fig. 12 is a graph comparing the reflection coefficient (S11) curves of the low SAR antenna device 100 provided in the embodiment of the present application with the free space state of the antenna device in the prior art. As can be seen from fig. 12, the low SAR antenna device 100 provided in the embodiment of the present application and the antenna device in the prior art both operate at 2.4 to 2.5GHz, which is an operating frequency band of WIFI 2.4G, and the center frequency is 2.45 GHz. Thus, it can be obtained that the sub radiation unit 130 does not substantially interfere and affect the operating frequency of the main radiation unit 110 in a free space state.

Fig. 13 is a graph comparing radiation efficiency curves of the low SAR antenna device 100 provided in the embodiment of the present application in a free space state compared to the antenna device in the prior art. As can be seen from fig. 13, the radiation efficiency and the system efficiency of the low SAR antenna device 100 provided in the embodiment of the present application, and the radiation efficiency and the system efficiency of the antenna device in the prior art are all around-1.3 dB at 2.45GHz, which are substantially the same. Thus, it can be obtained that the sub radiation unit 130 does not substantially interfere with and affect the radiation efficiency and the system efficiency of the main radiation unit 110 in the free space state.

Fig. 14 is a radiation pattern at 2.45GHz when the antenna device in the related art is in a free space state. Fig. 15 shows a radiation pattern of the low SAR antenna device 100 in the free space state at 2.45GHz according to the embodiment of the present application. As can be seen from fig. 14 and fig. 15, the patterns and directivity coefficients of the low SAR antenna device 100 provided in the embodiment of the present application and the antenna device in the prior art are substantially the same. In summary, the simulation results of fig. 12 to 15 show that the addition of the auxiliary radiating element 130 has substantially no influence on the radiation performance of the main radiating element 110 in the free space state.

Fig. 16 is a graph comparing the reflection coefficient (S11) curves of the low SAR antenna device 100 provided in the embodiment of the present application with the reflection coefficient curve of the antenna device in the state of 0mm in the human body in the prior art. As can be seen from fig. 16, the reflection coefficients of the low SAR antenna device 100 provided in the embodiment of the present application and the antenna device in the prior art are substantially the same at 2.45 GHz.

Fig. 17 is a graph comparing radiation efficiency curves of the low SAR antenna device 100 according to the embodiment of the present application with those of the antenna device in the prior art in a state of 0mm of the human body. As can be seen from fig. 17, after the auxiliary radiating element 130 is added to the low SAR antenna apparatus 100, the radiation efficiency and the system efficiency of the low SAR antenna apparatus 100 are both improved significantly, about 6dB, when the distance between the human body 300 and the low SAR antenna apparatus 100 is 0 mm.

Fig. 18 shows SAR values of the antenna device in the prior art in a state of 0mm of the human body. Fig. 19 shows SAR values of the low SAR antenna device 100 according to the embodiment of the present application in a state of 0mm of the human body. As can be seen from fig. 18 and fig. 19, the SAR hotspot distributions of the low SAR antenna device 100 provided by the embodiment of the present application and the antenna device in the prior art are substantially the same, but the SAR value of the low SAR antenna device 100 provided by the embodiment of the present application is 3.2W/kg, and the SAR value of the antenna device in the prior art is 4.4W/kg, and the SAR value of the low SAR antenna device 100 provided by the embodiment of the present application is significantly reduced compared to the antenna device in the prior art, because the radiation energy occupancy of the main radiation unit 110 is reduced and the radiation energy occupancy of the auxiliary radiation unit 130 is increased.

In summary, the above simulation results show that, in the embodiment of the present application, by adding one sub-radiating unit 130 to the feed transmission path between the main radiating unit 110 and the feed source 120, the sub-radiating unit 130 can realize a large reduction of the SAR value of the 0mm antenna of the human body only by using a small free space radiation energy ratio due to the difference between the traveling wave and the standing wave characteristics of the first transmission line 140 and the second transmission line 150, and the influence on the free space performance of the main radiating unit 110 is very weak.

In addition, it should be noted that in some embodiments, the secondary radiation unit 130 may be disposed on an inner surface of the battery cover, and specifically, the secondary radiation unit 130 may be a suspended metal, a graphene layer, or a transparent conductive layer. Of course, in some other embodiments, the secondary radiating element 130 may not be limited to a floating metal antenna, a graphene antenna, and a transparent antenna, for example, the secondary radiating element 130 disposed on the inner surface of the battery cover 25 may also be another antenna element disposed on the inner surface of the battery cover 25 capable of being coupled to radiate a signal.

In this way, the feed network can be mostly implemented by the secondary radiation unit 130 disposed on the inner surface of the battery cover, so that the layout area of the antenna on the metal frame can be reduced, and the influence on other antennas can be reduced, and the low SAR antenna apparatus 100 can be implemented in a limited design space, thereby effectively saving the antenna design space inside the electronic device 200 to a certain extent. To a certain extent, the low SAR antenna apparatus 100 can be implemented in a limited design space, and the antenna design space inside the electronic device 200 is effectively saved. Moreover, the low SAR antenna apparatus 100 does not need to additionally slot on the metal frame of the middle frame 220, so that the industrial design appearance of the electronic device 200 is not affected, and meanwhile, the influence of hand holding can be effectively reduced.

It should be noted that, the sub radiation unit 130 may be printed or adhered on the inner surface of the rear housing 250, or the sub radiation unit 130 may be embedded in the inner surface of the rear housing 250, and the specific arrangement manner of the sub radiation unit 130 on the inner surface of the rear housing 250 is not limited in the embodiment of the present application, and is not limited to the above example. Of course, in other embodiments, the secondary radiation unit 130 may also be disposed on the outer surface of the rear housing 250, which is not limited in this application.

It is understood that, in some embodiments, the low SAR antenna device 100 provided in the embodiments of the present application may include multiple sets of the main radiation units 110 and multiple sets of the sub-radiation units 130, so as to add more radiators, and the low SAR antenna device 100 can achieve coverage of more modes through the increase of the number of the radiators.

In addition, the Main radiating unit 110 and the auxiliary radiating unit 130 may be a diversity Antenna (Div Antenna), a WIFI Antenna, a bluetooth Antenna, a GPS Antenna, a Main Antenna (Main Antenna), or a Multiple-Input Multiple-Output (MIMO) Antenna with medium and high frequencies. When the main radiation unit 110 is located at the bottom of the electronic device 200, the SAR value of the electronic device 200 can be made low.

In the description of the embodiments of the present application, it should be noted that unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, a fixed connection, an indirect connection via an intermediary, a connection between two elements, or an interaction between two elements. Specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

Reference throughout this specification to apparatus or components, in embodiments or applications, means or components must be constructed and operated in a particular orientation and therefore should not be construed as limiting the present embodiments. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically stated otherwise.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the embodiments of the application and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "may include" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Finally, it should be noted that: although the embodiments of the present application have been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: it is to be understood that modifications may be made to the technical solutions described in the foregoing embodiments, or some or all of the technical features may be equivalently replaced, and the modifications or the replacements may not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A low SAR antenna device applied to electronic equipment is characterized by at least comprising:

at least one main radiating element and at least one feed;

further comprising: one end of the auxiliary radiating unit is connected with the main radiating unit, and the other end of the auxiliary radiating unit is connected with the power feed;

the feeding source feeds power to the main radiating element and the auxiliary radiating element respectively, and the auxiliary radiating element does not generate resonance on the working frequency of the main radiating element;

further comprising: a first transmission line and a second transmission line; one end of the first transmission line is connected with the main radiating unit, and the other end of the first transmission line is connected with the auxiliary radiating unit; one end of the second transmission line is connected with the auxiliary radiating unit, and the other end of the second transmission line is connected with the feed power supply;

the length of the first transmission line is between 1/8 lambda and lambda; wherein λ is the wavelength of the electromagnetic wave in the first transmission line medium.

2. The low SAR antenna device of claim 1, wherein the resonance frequency of the secondary radiating element is greater than the resonance frequency of the main radiating element, and the resonance frequency of the secondary radiating element is less than or equal to 3 times the resonance frequency of the main radiating element.

3. The low SAR antenna device of claim 1, wherein the length of the first transmission line is between 1/8 λ and 1/2 λ.

4. The low SAR antenna device according to any of claims 1 to 3, further comprising: a matching circuit; one end of the matching circuit is connected with the main radiating unit, and the other end of the matching circuit is connected with the first transmission line.

5. The low SAR antenna device of claim 4, characterized in that the matching circuit comprises at least: any one or more of a capacitor, an inductor, or a resistor.

6. The low SAR antenna device according to any of claims 1 to 3, further comprising: a third transmission line between the first transmission line and the second transmission line;

the number of the secondary radiation units is two; one end of one of the two auxiliary radiating elements is connected with the first transmission line, and the other end of one of the two auxiliary radiating elements is connected with the third transmission line; one end of the other of the two auxiliary radiating elements is connected with the third transmission line, and the other end of the other of the two auxiliary radiating elements is connected with the second transmission line.

7. The low SAR antenna device according to any of claims 1 to 3, further comprising: a fourth transmission line and a fifth transmission line;

the number of the secondary radiation units is two; one end of the fourth transmission line is connected with the main radiating element, and the other end of the fourth transmission line is connected with one end of one of the two auxiliary radiating elements; one end of the fifth transmission line is connected with the other end of one of the two auxiliary radiating units, and the other end of the fifth transmission line is connected with the power supply;

one end of the other of the two auxiliary radiating elements is connected with the first transmission line, and the other end of the other of the two auxiliary radiating elements is connected with the second transmission line.

8. An electronic device, characterized in that it comprises at least: display screen, backshell and be located the display screen with the center between the backshell still includes: the low SAR antenna device of any of the previous claims 1-7;

the middle frame is a metal middle frame, the metal middle frame at least comprises a metal frame, and the metal frame forms at least one main radiation unit in the low SAR antenna device.

9. The electronic device of claim 8, wherein the secondary radiating element in the low SAR antenna apparatus is a metal sheet.

10. The electronic device of claim 8, wherein the metal bezel further comprises: a metal middle plate; the metal frame is arranged around the periphery of the metal middle plate;

and the vertical distance between the auxiliary radiation unit of the low SAR antenna device and the metal middle plate is 0.5mm-3 mm.