CN119208973B

CN119208973B - Antenna device and electronic equipment

Info

Publication number: CN119208973B
Application number: CN202310775241.2A
Authority: CN
Inventors: 文思超; 李孔政
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2023-06-27
Filing date: 2023-06-27
Publication date: 2025-09-26
Anticipated expiration: 2043-06-27
Also published as: CN119208973A

Abstract

The application provides an antenna device and electronic equipment. The antenna device comprises a circuit board, a first antenna, a second antenna and a third antenna, wherein the first antenna is an inverted-F antenna, the first antenna comprises a feed-in end and a grounding end which extend outwards from the circuit board, and antenna conductors connected with the feed-in end and the grounding end, the second antenna is an antenna based on a split ring resonator, the second antenna comprises a first branch, a second branch, a third branch and a fourth branch, the first branch and the second branch extend outwards from the circuit board, a gap between the third branch and the fourth branch forms an opening part of the split ring resonator, and the grounding end of the first antenna and the first branch are identical in radiator. According to the antenna device and the electronic equipment provided by the scheme, the common radiator antenna is formed by the first antenna and the second antenna, and the grounding end of the first antenna is used as a part of radiator of the second antenna, so that the size of the antenna device is reduced, and the isolation degree of the antenna device is improved.

Description

Antenna device and electronic equipment

Technical Field

The present application relates to the field of communications technologies, and in particular, to an antenna apparatus and an electronic device.

Background

With the development and progress of technology, electronic devices with communication functions, such as mobile phones, are becoming more popular and powerful in daily life. In order to achieve miniaturization of electronic devices, the related art may reduce the antenna size in a manner of a co-radiator antenna.

However, the design of the co-radiator antenna adopted in the related art still has the problems that the co-radiator antenna is large in size and the isolation between the co-radiator antennas is poor.

Disclosure of Invention

The embodiment of the application aims to provide an antenna device and electronic equipment, so as to reduce the size of a co-radiator antenna and improve the isolation degree between the co-radiator antennas.

In a first aspect, an antenna device is provided, comprising a circuit board, a first antenna, a second antenna and a third antenna, wherein the first antenna is an inverted-F antenna, the first antenna comprises a feed end and a ground end which extend outwards from the circuit board, and an antenna conductor connected with the feed end and the ground end, the second antenna is an antenna based on a split ring resonator, the second antenna comprises a first branch, a second branch, a third branch and a fourth branch, the first branch and the second branch extend outwards from the circuit board, a gap between the third branch and the fourth branch forms an opening part of the split ring resonator, and the ground end of the first antenna and the first branch are the same radiator.

As a possible implementation manner, the antenna device further comprises a first capacitor, one end of the first capacitor is connected with the third branch, and the other end of the first capacitor is connected with the fourth branch.

As a possible implementation manner, the first capacitor is a variable capacitor.

As a possible implementation manner, the antenna device further comprises a tuning device, one end of the tuning device is connected with the tail end of the antenna conductor, the other end of the tuning device is connected with the circuit board, and the tuning device is used for tuning the first antenna.

As a possible implementation, the antenna device further comprises a first inductance connected in parallel with the first capacitance.

As a possible implementation manner, the antenna device further comprises a third antenna, wherein the third antenna is an inverted-F antenna, the third antenna comprises a feed end and a grounding end which extend outwards from the circuit board, and an antenna conductor connected with the feed end of the third antenna and the grounding end of the third antenna, and the grounding end of the third antenna and the second branch are the same radiator.

As a possible implementation, the antenna conductor of the first antenna and the antenna conductor of the third antenna are different in length.

As one possible implementation, the circuit board includes a first recess between the first stub and the second stub, the circuit board providing feed excitation to the second antenna through the first recess.

As a possible implementation, the operating frequencies of the first antenna and the second antenna are different.

In a second aspect, an electronic device is provided, comprising an antenna arrangement as described in the first aspect or any one of the possible implementation manners of the first aspect.

The application forms a common radiator antenna by using the first antenna (inverted F antenna) and the second antenna (antenna based on the split ring resonator), and takes the grounding end of the first antenna as a part of radiator of the second antenna, so as to reduce the size of the antenna device and improve the isolation degree of the antenna device.

Drawings

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

Fig. 2 shows a current distribution diagram of an antenna device according to an embodiment of the present application.

Fig. 3 is an S-parameter diagram of an antenna device according to an embodiment of the present application.

Fig. 4 is a schematic diagram of a simulated current distribution diagram of an antenna device according to an embodiment of the application.

Fig. 5 is a schematic diagram showing a simulated current distribution diagram of an antenna device according to another embodiment of the present application.

Fig. 6 is a system efficiency diagram of an antenna device according to an embodiment of the present application.

Fig. 7 is a schematic structural diagram of an antenna device according to another embodiment of the present application.

Fig. 8 is an S-parameter diagram of an antenna device according to another embodiment of the present application.

Fig. 9 is a system efficiency diagram of an antenna device according to another embodiment of the present application.

Fig. 10 shows a radiation pattern of an antenna device according to an embodiment of the present application.

Fig. 11 is an S-parameter diagram of an antenna device according to another embodiment of the present application.

Fig. 12 is a schematic structural diagram of an antenna device according to another embodiment of the present application.

Fig. 13 is an S-parameter diagram of an antenna device according to another embodiment of the present application.

Fig. 14 is a schematic structural diagram of an antenna device according to another embodiment of the present application.

Fig. 15 is a schematic structural diagram of an antenna device according to another embodiment of the present application.

Fig. 16 is an S-parameter diagram of an antenna device according to another embodiment of the present application.

Fig. 17 is an S-parameter diagram of an antenna device according to another embodiment of the present application.

Fig. 18 is a schematic structural diagram of an antenna device according to another embodiment of the present application.

Fig. 19 is a schematic diagram showing a simulated current distribution of an antenna device according to another embodiment of the present application.

Fig. 20 is a schematic diagram showing a simulated current distribution of an antenna device according to another embodiment of the present application.

Fig. 21 is a schematic diagram showing a simulated current distribution of an antenna device according to another embodiment of the present application.

Fig. 22 is a schematic structural diagram of an antenna device according to another embodiment of the present application.

Fig. 23 is an S-parameter diagram of an antenna device according to another embodiment of the present application.

Fig. 24 is a system efficiency diagram of an antenna device according to another embodiment of the present application.

Fig. 25 is a schematic structural diagram of an antenna device according to another embodiment of the present application.

Fig. 26 is a schematic structural diagram of an antenna device according to another embodiment of the present application.

Fig. 27 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments.

The embodiment of the application can be applied to the scene that the antenna device in the electronic equipment receives and transmits the wireless electromagnetic wave signals. For easy understanding, the electronic device according to the embodiment of the present application will be described in detail.

The electronic device mentioned in the embodiment of the present application may be any type of electronic device having a wireless communication function. For example, the electronic device may be a portable mobile terminal or a handheld mobile terminal. As a specific example, the electronic device may be a cell phone, a mobile phone or smart phone, a portable game device, a laptop, a tablet, a Personal Digital Assistant (PDA), a portable internet device, a music player or a data storage device.

In order to make the structure of the electronic device more compact, the related art generally adopts a co-radiator antenna mode, so that the internal space is saved. The plurality of antennas share the radiator, namely, the plurality of antennas share one radiator (such as an antenna bracket, a circuit board, an antenna housing and the like) as a radiation source of the antenna, and the plurality of antennas work on the same radiator through reasonable design and adjustment, so that the purposes of reducing space occupation, simplifying an antenna system structure, improving the performance of the antenna system and the like are achieved.

In the antenna device applied at present, the type of the antenna is not limited, and for example, the antenna of the co-radiator may be a monopole antenna. A monopole antenna is an antenna having only one conductor, one of which is fixed to the ground or to another support, and the other of which acts as the radiating portion of the antenna. The monopole antenna has the characteristics of easy manufacture and installation and low cost, and is suitable for short-distance communication and low-frequency signal transmission. But its radiation efficiency is relatively low, requires a large space for arrangement, and is susceptible to the surrounding environment, resulting in unstable signal quality.

For another example, the antenna of the co-radiator may be an inverted-F antenna (IFA). The inverted-F antenna is an antenna based on microstrip line technology, and works in a quarter-wavelength mode. It is shaped like the letter "F", but unlike conventional F-antennas, an inverted-F antenna is called an inverted-F antenna because the upper half of the antenna is folded in the opposite direction to form an inverted "L" shape. The inverted-F antenna has broadband characteristics and can cover a plurality of frequency bands. The inverted-F antenna can be embedded in a simple printed circuit board (printed circuit board, PCB) to form an integrated antenna at a low cost. And, the inverted-F antenna can be used in a plurality of application fields such as mobile phones, wireless local area networks (WIRELESS FIDELITY, wi-Fi), bluetooth (BT), global positioning systems (global positioning system, GPS) and the like.

However, current designs typically employ the same type of co-radiator antenna, e.g., two monopole co-radiator antennas, or two inverted-F co-radiator antennas. On the one hand, the antenna device adopted in the related art has a structure using the co-radiator, but each antenna still works in a mode of quarter wavelength or even half wavelength, the size is still relatively large, and the whole space cannot be utilized to the maximum extent. On the other hand, since the co-radiator antennas employed in the related art are the same antenna, which generally operate in similar frequency bands, isolation between the antennas is poor when operating, resulting in high current coupling between the antennas. In order to solve the problem of current coupling, measures such as a filter circuit are added, so that the circuit structure is more complex.

As one possible implementation manner, the related art may employ a left-hand mode to achieve miniaturization of an antenna device, that is, rotate an electromagnetic wave into a left-hand helicon wave using rotational symmetry of an electromagnetic field, and the electromagnetic wave has a very specific polarization, and may be received or transmitted through a very small antenna, thereby achieving miniaturization of the antenna device.

However, the left-hand antenna used in the related art may reduce the antenna length to about one eighth of the wavelength, but the operation efficiency is often low, and further miniaturization is difficult.

In view of the above problems, an embodiment of the present application provides an antenna device, including a circuit board, a first antenna (inverted-F antenna) and a second antenna (antenna based on a split ring resonator), where a common radiator antenna is formed by using the first antenna and the second antenna, and a ground terminal of the first antenna is used as a part of a radiator of the second antenna, so as to reduce the size of the antenna device and improve the isolation of the antenna device.

Referring to a specific structure of the antenna device in fig. 1, an antenna device 100 according to an embodiment of the present application includes a circuit board 11, a first antenna 12, and a second antenna 13.

The circuit board 11 may serve as a base structure of the antenna, in which the antenna is fixed. The circuit board 11 may be used to control the antenna device, for example, to control the antenna device to transceive signals, to adjust the antenna device to transceive signals, etc. In some embodiments, the circuit board 11 may also provide support and fixation for the antenna arrangement. In addition, the circuit board 11 can also serve as a radiation surface and a receiving surface of the antenna, so that the transmission capability of the antenna is enhanced. The type of the circuit board 11 is not limited in the embodiment of the present application, and for example, the circuit board 11 may be a flexible circuit board (flexible printed circuit, FPC), a laser direct structuring (LASER DIRECT structuring, LDS) circuit board, a printed direct structuring (PRINT DIRECT structuring, PDS) circuit board, and a printed circuit board (printed circuit board, PCB).

As a more specific example, in the embodiment of the present application, the circuit board 11 may be a PCB, and the PCB has advantages of high precision, space saving, low cost, etc., and the antenna is embedded into the PCB to work, so that not only stability and reliability of the circuit board 11 can be ensured, but also the internal space of the antenna device 100 can be saved, and the cost can be saved.

Further, the specific kind of the first antenna 12 is not limited in the embodiment of the present application, for example, the first antenna 12 may be an inverted-F antenna or an antenna based on a split-ring resonator (SRR). As a more specific example, the first antenna 12 in the embodiment of the present application is an inverted-F antenna, which can cover multiple communication frequency bands and is widely applied to electronic devices such as mobile phones.

The embodiment of the present application is described taking the first antenna 12 as an inverted-F antenna as an example, but the first antenna 12 may also be another antenna besides the inverted-F antenna, for example, the first antenna 12 may be an SSR-based antenna. Referring to the first antenna 12 shown in fig. 1, the first antenna 12 is an inverted F antenna including a feed end 122 and a ground end 124 extending outwardly from the circuit board 11, and an antenna conductor 123 connected to the feed end 122 and the ground end 124. The feed end 122 of the first antenna 12 extends out of the circuit board 11, and is used for transmitting the received signal to the circuit board 11 for subsequent signal processing and data transmission. The ground terminal 124 of the first antenna 12 is connected to ground for providing an effective ground reference point for the first antenna 12 to ensure stability and reliability of operation of the first antenna 12 and to protect electronic equipment from lightning strikes and static electricity. The antenna conductor 123 of the first antenna 12 is connected to the feed end 122 and the ground end 124 of the first antenna 12, and mainly plays roles of conducting and radiating electromagnetic waves. The feed 122, ground 124 and antenna conductor 123 of the first antenna 12 cooperate to perform the function of signal transmission.

Further, the specific type of the second antenna 13 is not limited in the embodiment of the present application, for example, the second antenna 13 in fig. 1 may be an inverted F antenna or an SRR-based antenna. As a more specific example, in an embodiment of the present application, the second antenna 13 is an SRR based antenna. The SRR-based antenna is a microstrip antenna, and is characterized by wider working frequency band, and is especially suitable for a broadband communication system. The structure is simple, the manufacture and the integration are easy, and the directivity and the polarization characteristics are good. The SRR antenna also has good radiation efficiency and impedance matching properties and can operate in different media and environments. Meanwhile, the anti-interference device also has certain anti-interference capability and reliability, and can meet the requirements of different application occasions.

The embodiment of the present application is described taking the second antenna 13 as an SRR-based antenna as an example, but the second antenna 13 may be other antennas than the SRR-based antenna, for example, an inverted F antenna. Referring next to fig. 1, the second antenna 13 shown in fig. 1 is an SRR-based antenna including a first stub 131, a second stub 132, a third stub 133, and a fourth stub 134, the first stub 131 and the second stub 132 extending outwardly from the circuit board 11, a gap between the third stub 133 and the fourth stub 134 forming an open portion of a split-ring resonator. The first branch 131 and the second branch 132 extend outwards from the circuit board 11, so as to realize a signal transmission function. A gap is formed between the third stub 133 and the fourth stub 134, which serves as an opening portion of the split-ring resonator, and radiation and reception of electromagnetic waves are achieved by the split-ring structure.

In the embodiment of the present application, the grounding end 124 of the first antenna 12 and the first branch 131 of the second antenna 13 are the same radiator for receiving or transmitting electromagnetic waves, so as to realize an antenna common structure. According to the antenna device 100 provided by the embodiment of the application, the first antenna 12 and the second antenna 13 share one radiator, so that the problems existing in the related art are effectively avoided, the isolation degree of the antenna device 100 is improved, and the structure miniaturization of the antenna device 100 is further realized under the condition of higher working efficiency.

It should be noted that, the antenna device in the embodiment of the present application may be implemented by using different types of antennas (for example, two different types of antennas) and sharing one radiator. In the embodiment of the application, the different types of antennas in the co-radiator antenna are not limited, for example, the different types of antennas can be an inverted-F antenna and an SRR-based antenna respectively. As a more specific example, in the embodiment of the present application, the first antenna is an inverted-F antenna, and the second antenna is an SRR-based antenna.

It should be understood that fig. 1 is only a schematic diagram of the antenna arrangement 100, the actual antenna arrangement 100 may also comprise more devices than shown in fig. 1, or the actual antenna arrangement 100 may also comprise fewer devices than shown in fig. 1.

In some embodiments, the feed end 122 of the first antenna is directed to an end outside the circuit board 11, and a first feed point 121 is further provided. When the antenna arrangement is in operation, feed excitation may be provided to the first antenna via the first feed point 121.

In some embodiments, the circuit board 11 may further include a first groove 136, where the first groove 136 is located between the first branch 131 and the second branch 132, and a second feeding point 135 is disposed at an opening of the first groove 131, and the circuit board 11 provides feed excitation to the second antenna 13 through the first groove 131. The second antenna 13 excites the feed source at the opening of the first recess 136 of the circuit board 11, and compared with the traditional mode of exciting the antenna at the opening end of the second antenna 13, the mode of exciting the antenna at the opening of the first recess 136 of the circuit board 11 is simpler, the device is further simplified, and the cost is saved.

As shown in fig. 2, the first feeding point 121 of the first antenna 12 is a top end of the feeding end 122 extending from the circuit board 11, and the current is emitted from the first feeding point 121 and moves along the antenna conductor 123 of the first antenna. The current of the second antenna 13 may flow from the feed, in the direction of the second antenna branch, and finally back to the feed. Taking the second feeding point 135 excited by the feed source at the opening of the first groove 136 as an example, as can be seen from the current direction of the second antenna 13 in fig. 2, the current of the second antenna 13 flows from the second feeding point 135, flows along the directions of the first branch 131, the third branch 133, the fourth branch 134 and the second branch 132, and finally is input to the opening of the first groove 136.

In the antenna device 100 provided by the embodiment of the application, since the first antenna 12 and the second antenna 13 are different types of antennas, the two antennas can work in different frequency bands, so that the isolation of the antenna device 100 is improved. The working frequency bands of the first antenna 12 and the second antenna 13 are not limited in the embodiments of the present application, for example, the first antenna 12 may work in the B41/n41 frequency band or the B40/n40 frequency band, and the second antenna 13 may work in the n78 frequency band. As a more specific example, in the embodiment of the present application, the first antenna 12 operates in the B41/n41 frequency band, and the second antenna 13 operates in the n78 frequency band. Because the frequency bands of the two antennas are different, the working frequency difference is larger, and therefore, when the two antennas work, the isolation between the two antennas is very high, and the mutual influence can be effectively avoided.

Further, reference may be made to the S-parameter (S-Parameters) graph of fig. 3, where the S-parameter is used to describe the transmission and reflection of signals in an antenna, including loss coefficients, isolation coefficients, and the like. In fig. 3, the X-axis represents the frequency of operation of the antenna in gigahertz (GHz), and the Y-axis represents the power of the signal in decibels (dB). As shown in fig. 3, in the embodiment of the present application, S1,1 is a return loss curve of the first antenna 12, S2,2 is a return loss curve of the second antenna 13, and S2,1 is an isolation curve of the first antenna 12 and the second antenna 13. As can be seen from the S1,1 and S2,2 curves in fig. 3, the first antenna 12 operates at a frequency of about 2.5GHz and the second antenna 13 operates at a frequency of about 3.5 GHz. In addition, as can be seen from the S2,1 curve, the isolation of the two antennas is-17 dB when operating at the frequency of 2.5GHz, and the isolation reaches-37 dB when operating at the frequency of 3.5 GHz. Therefore, the isolation between the two antennas is high.

Further, see the simulated current profiles of the first antenna 12 and the second antenna 13 in fig. 4 and 5. As shown in fig. 4 and 5, it can be seen that the distribution of the current during operation of the first antenna 12 and the second antenna 13 is consistent with the current profile shown in fig. 2. As shown in fig. 4, when the first antenna 12 is excited, the current moves along the feeding end 122 and the antenna conductor 123, and at this time, it can be seen that the current coupled out from the second antenna 13 is weak, and the influence on the second antenna 13 when the first antenna 12 is operated is small. Also, referring to fig. 5, when the second antenna 13 is excited, a current flows in the direction of the first branch 131-the third branch 133-the fourth branch 134-the second branch 132. In this case, the current coupled out from the first antenna 12 is also very weak, which means that the second antenna 13 has little influence on the first antenna 12 when it is in operation. Therefore, it was further confirmed that the first antenna 12 and the second antenna 13 are highly isolated and hardly affect each other in operation.

Further, in order to verify the operation efficiency of the antenna device 100, the overall system operation efficiency (system total efficiency) of the two antennas when operated is shown in fig. 6. In fig. 6, the X-axis represents the frequency in GHz at which the antenna operates, and the Y-axis represents the efficiency of the signal in dB. As can be seen from the curve S31 in fig. 6, the working efficiency of the first antenna 12 reaches the highest point, about 0dB, i.e. about 100%, when working at a frequency of 2.5GHz, and the working efficiency of the second antenna 13 reaches the highest point, about 0dB, i.e. about 100%, when working at a frequency of 3.5GHz, as can be seen from the curve S32. Therefore, it can be seen that when the two antennas work in respective working frequency bands, the state with higher working efficiency can be achieved.

In order to make the antenna operate in more frequency bands, as shown in fig. 7, the antenna device in the embodiment of the present application further includes a first capacitor C1, where one end of the first capacitor C1 is connected to the third branch 133 of the second antenna 13, and the other end of the first capacitor C1 is connected to the fourth branch 134 of the second antenna 13. The second antenna 13 in the embodiment of the present application works in the resonance mode of the split ring resonator, and the open end of the antenna branch may be connected in parallel with a capacitor C1, and since the resonance frequency of the split ring resonator is mainly determined by the magnitude of the equivalent capacitance value, the frequency of the antenna work may be changed by changing the magnitude of the capacitance value.

Further, since the second antenna 13 can change the operating frequency of the second antenna 13 by changing the magnitude of the capacitance value of the open end. Therefore, the second antenna 13 can be free from the limitation of the antenna size, and the state of the antenna operating at a low frequency can be realized by controlling the antenna operating frequency with one large capacitance in the case of a small size. The size of the second antenna 13 is small enough, for example, the S-parameter diagram of the second antenna 13 shown in fig. 8 can be much smaller than a quarter wavelength, and under this size, by adjusting the capacitance value of the open end of the second antenna 13, an antenna operating in the lower frequency band of GPS L1 (global positioning system L, GPS L1) with an operating frequency of 1.57542GHz can be obtained. The working efficiency can be seen in fig. 9. It can be seen that in this case, the efficiency of the operation of the second antenna 13 is still high.

The antenna can operate in a lower frequency band by using a larger capacitor in a smaller size. In order to ensure that the antenna can still achieve higher radiation efficiency and has good signal receiving capability in the state, the embodiment of the application can observe the signal receiving condition of the first antenna and/or the second antenna through the radiation pattern of the antenna. The application device of the antenna device is not limited in the embodiment of the present application, and for example, the application device may be an electronic device with a communication function. As a more specific example, the application device may be a cell phone. As shown in the radiation pattern of the second antenna 13 in the mobile phone shown in fig. 10, the second antenna 13 operates in the GPS L1 frequency band, and the operating frequency is 1.57542GHz. It can be seen that the upper hemispherical duty ratio of 51% can be obtained when the second antenna 13 is placed in the middle of the mobile phone, and at this time, the radiation efficiency of the system is-2.688 dB, and the total efficiency of the system is-2.956 dB. This means that the second antenna 13 is placed in the middle of the handset, and can capture 51% of the signal in the upper hemisphere area, at which point the second antenna 13 can provide good signal reception and transmission capabilities.

According to the analysis, the antenna device provided by the embodiment of the application can further realize miniaturization of the antenna device under the condition of ensuring the working efficiency.

The embodiment of the application does not limit the form of the first capacitor connected in series with the open end of the second antenna 13, and the capacitance value connected in series with the open end can be adjusted, so that the working efficiency of the second antenna 13 can be adjusted.

As a possible implementation manner, in the embodiment of the present application, the capacitor connected in series with the open end of the second antenna 13 may be an equivalent capacitor C.

The implementation manner how to change the capacitance of the equivalent capacitor C is not particularly limited in the embodiments of the present application, and for example, it is considered that the opening size and/or the relative area size of the opening end of the second antenna may affect the capacitance of the equivalent capacitor C, so the capacitance of the equivalent capacitor C may be changed by changing the opening size and/or the relative area size of the opening end of the second antenna.

As shown in fig. 11, the operating frequency variation curve of the second antenna 13 is shown under different equivalent capacitances (C1/C2/C3 in fig. 11 are different equivalent capacitance values, where C1> C2> C3). As can be seen from fig. 11, as the equivalent capacitance decreases, the operating frequency of the second antenna 13 corresponding to the equivalent capacitance becomes gradually larger. That is, the larger the capacitance value, the smaller the operating frequency of the antenna.

As another possible implementation manner, in an embodiment of the present application, the first capacitor connected in series with the open end of the second antenna 13 may be a tunable device. For example, the tunable device may be a switch or variable capacitor. As a more specific example, the first capacitor provided in the embodiment of the present application may be a variable capacitor. As shown in fig. 12, the open end of the second antenna 13 may be connected in series with a variable capacitor C2. In the implementation manner, the variable capacitor C2 can change the capacitance value by changing the conditions of the voltage, the electric field and the like, so that the operation is convenient, the multi-band tuning coverage can be realized by changing various capacitance values, and the communication performance of the antenna device is further improved.

The tuning manner of the first antenna 12 is not limited in the embodiments of the present application, for example, the first antenna 12 may adjust the operating frequency by changing its physical length, or the first antenna 12 may adjust its operating frequency by setting a tunable device.

As one possible implementation, the operating frequency of the first antenna 12 in the embodiment of the present application may be determined by the length of the antenna, and it should be understood that the first antenna 12 may adjust its operating frequency by changing the length of the antenna, i.e. by changing the length of the conductor in the first antenna 12. Taking the example of the first antenna operating in a quarter wavelength resonant mode, the antenna lengths L1, L2 and L3 are different, and L1> L2> L3. As shown in fig. 13, the antenna is operated at three different lengths L1, L2 and L3, respectively. As can be seen from the trend of the curve, the operating frequency of the first antenna 12 of the L1 length is lower than the operating frequency of the first antenna 12 of the L2 length, and the operating frequency of the first antenna 12 of the L2 length is lower than the operating frequency of the first antenna 12 of the L3 length. Therefore, the longer the first antenna 12 is, the lower the operating frequency thereof, and the antennas of different operating frequencies can be realized by adjusting the length of the antennas. The implementation mode is simple to operate and simple in structure, the adjusting function can be achieved without adding other devices, and the structure of the antenna device is further simplified.

As another possible implementation manner, as shown in fig. 14, the antenna apparatus in the embodiment of the present application further includes a tuning device 126, where one end of the tuning device 126 is connected to the end of the antenna conductor 123 of the first antenna 12, the other end of the tuning device 126 is connected to the circuit board 11, and the tuning device 126 is used to tune the first antenna 12. The kind of the tuning device 126 of the first antenna 12 is not limited in the embodiment of the present application, and for example, the tuning device 126 may be a switching device or an adjustable capacitor. The tuning device 126 may adjust the first antenna 12 to operate at a greater range of frequencies, which implementation is simple to operate and increases the flexibility of the antenna arrangement.

In some embodiments, the embodiments of the present application may tune the first antenna and the second antenna simultaneously, so as to achieve independent tuning between the first antenna and the second antenna.

The tuning modes of the first antenna and the second antenna are not limited in the embodiment of the application. In some embodiments, the first antenna and the second antenna may be tuned in the same tuning manner, e.g., both tuned in a variable capacitance manner. In some embodiments, the first antenna and the second antenna may be tuned differently, for example, the first antenna may be tuned by a switching device and the second antenna may be tuned by varying the capacitance value of a variable capacitor having its open ends connected in series.

Further, the first antenna 12 and the second antenna 13 in the embodiment of the present application may be tuned independently. Since the first antenna 12 and the second antenna 13 operate at different frequencies, respectively, when the frequency of one antenna is adjusted, no influence is exerted on the other antenna.

The tuning modes of the first antenna 12 and the second antenna 13 are not limited in the embodiment of the present application, for example, in the embodiment of the present application, the first antenna 12 may be tuned by changing its own length, or may be tuned by adding a tuning device at the end of the first antenna 12. As a more specific example, taking the tuning mode of the first antenna 12 as an example of adjusting the self length, referring to fig. 13, it is known that when the first antenna 13 changes the self length to L1, L2 and L3, the operating frequency of the second antenna 12 is hardly affected, and still is around 3.5 GHz. Therefore, when the first antenna 13 is tuned, the operating frequency of the second antenna 12 is not changed, and independent tuning of the two antennas can be achieved.

Likewise, the frequency of the first antenna 12 is hardly affected when the second antenna 13 is tuned. The tuning manner of the second antenna 13 is not limited in the embodiment of the present application, for example, the second antenna 13 may change the operating frequency by changing the equivalent capacitance value of the open end, or the second antenna 13 may change the operating frequency by adjusting the variable capacitance of the open end. As a more specific example, taking the tuning mode of the second antenna 13 as an example to change the equivalent capacitance value of the open end, as shown in fig. 11, it is known that when the second antenna 13 changes the capacitance values C1, C2, and C3, the operating frequency of the first antenna 12 is also hardly affected, as shown by S1,1 (C1), S1,1 (C2), and S1, and 1 (C3), and still is about 2.5 GHz.

As can be seen from the above illustration and analysis, the first antenna 12 and the second antenna 13 can be tuned independently, and the operating frequencies of the other antennas are not affected when the two antennas adjust their own operating frequencies. Therefore, the antenna device provided by the embodiment of the application further improves the isolation degree of the antenna, reduces the coupling between antenna circuits, and improves the working stability and reliability of the antenna device.

In some embodiments, as shown in fig. 15, the antenna device in the embodiment of the present application may further include a first inductor L5 connected in parallel with the first capacitor C1 to form a capacitive-inductive parallel circuit. When the capacitor C1 and the inductance L5 are connected in parallel, a resonance circuit can be formed. The resonant frequency is changed by changing the value of the capacitor C1, and the working frequency of the antenna is adjusted, so that the working frequency of the antenna can be changed in a larger range, and the isolation between the antennas is further improved.

Taking the example that the co-radiator antenna comprises three antennas (for the specific structure that the co-radiator comprises three antennas, see the description below, which is not repeated here), the isolation between the first antenna and the second antenna and the isolation between the second antenna and the third antenna are further improved. Taking the S-parameter diagram of the three-antenna co-radiator antenna device shown in fig. 16 as an example, it can be seen from the curves S2,1 that the isolation between the first antenna and the second antenna is reduced below-20 dB. Similarly, the isolation between the second antenna and the third antenna is reduced to-20 dB or less. The isolation between the first antenna and the second antenna, and the isolation between the second antenna and the third antenna are all further improved compared to an antenna device without a capacitive-inductive parallel circuit. The S parameter diagram of the antenna device without the capacitor-inductor parallel circuit can be seen in fig. 17, and as shown in fig. 17, in curves S2 and 1, the isolation of the two antennas is below-12 dB when the two antennas work in the frequency band of 2.5 GHz.

It should be noted that, the number of antennas is not limited by the antenna device provided by the embodiment of the present application, and the description is given above taking the case that the co-radiator antenna includes two antennas as an example, but the number of antennas in the antenna device provided by the embodiment of the present application may be greater than two (e.g., 3, 4, etc.). In the following, taking an example that the co-radiator antenna includes three antennas, other examples of the antenna device provided by the embodiment of the present application are given.

For example, the antenna device may be a device in which three antennas share a radiator. That is, the antenna device provided in the embodiment of the present application may further include a third antenna, where the third antenna forms a co-radiator antenna with the first antenna and the second antenna.

In some embodiments, the type of third antenna may be the same as the type of first antenna. For example, the third antenna and the first antenna may both be inverted-F antennas, or the third antenna and the first antenna may both be SRR-based antennas, or the like. The antenna device provided by the embodiment of the application is described below by taking the inverted-F antenna as an example of the third antenna and the inverted-F antenna.

The third antenna may be an inverted-F antenna, and the third antenna includes a feed end and a ground end extending outward from the circuit board, and an antenna conductor connected to the feed end of the third antenna and the ground end of the third antenna, where the ground end of the third antenna and the second branch are the same radiator.

The specific structure of the three-wire co-antenna device provided in the embodiment of the present application is shown in fig. 18, and includes a circuit board 20, a first antenna 21, a second antenna 22 and a third antenna 23. The circuit board 20 of the three-wire co-body antenna device is not limited in the present application, and for example, the circuit board 20 may be a flexible circuit board, a laser direct structuring circuit board, or a printed direct structuring circuit board. As a more specific example, in an embodiment of the present application, the circuit board 20 may be a printed circuit board. As can be seen from fig. 18, the first antenna 21 includes a feed end 212, a feed point 211 and a ground end 214 extending outwardly from the circuit board 20, and an antenna conductor 213 connected to the feed end 212 and the ground end 214, the second antenna 22 includes a first branch 221, a second branch 222, a third branch 223 and a fourth branch 224, the first branch 221 and the second branch 222 extending outwardly from the circuit board 20, a gap between the third branch 223 and the fourth branch 224 forming an opening portion of the split ring resonator, and the third antenna 23 includes a feed end 232 and a ground end 234 extending outwardly from the circuit board 20, and an antenna conductor 233 connected to the feed end 232 of the third antenna 23, the feed point 231 and the ground end 234 of the third antenna 23. It can be seen that the ground 214 of the first antenna 21 and the first branch 221 of the second antenna 22 are the same radiator, and the ground 234 of the third antenna 23 and the second branch 222 of the second antenna 22 are the same radiator. The antenna device with the three-wire shared radiator further reduces the volume of the antenna device on the basis of increasing the communication range, and realizes the miniaturization of the antenna device.

The frequency band of the three antennas is not limited in the embodiment of the present application, for example, the first antenna 21 may operate in the B41/n41 frequency band or the B40/n40 frequency band, the second antenna 22 may operate in the n78 frequency band, and the third antenna 23 may operate in the B41/n41 frequency band or the B40/n40 frequency band. As a more specific example, the first antenna 21 and the third antenna 23 in the embodiment of the present application operate in the B41/n41 frequency band, and may be applied to a 5G New Radio (NR) system mobile communication or a 4G Long Term Evolution (LTE) system mobile communication, the second antenna 22 operates in the n78 frequency band, and may be applied to a global positioning system (global positioning system, GPS), and the three antennas operate together, so that the communication of the antenna apparatus 200 in multiple frequency bands may be realized. And, when the three antennas respectively work in the respective frequency bands, the method can be applied to a multiple input multiple output (multiple input multiple output, MIMO) system. MIMO systems may utilize multiple antennas to transmit and receive data between a transmitting end and a receiving end. The MIMO system not only transmits more data, but also can improve the transmission rate and the channel capacity, thereby improving the reliability and stability of data transmission. Therefore, the three-antenna-in-one antenna device reduces the volume of the device on one hand, increases the working frequency band on the other hand, improves the transmission speed of the device, and further effectively improves the communication capability of the device.

When the first antenna 21 and the third antenna 23 operate in the B41/n41 frequency band and the second antenna 22 operates in the n78 frequency band, the S-parameter curve of the operation of the antenna device is shown in fig. 17. S1,1 is the return loss curve of the first antenna 21, S2,2 is the return loss curve of the second antenna 22, S2,1 is the isolation curve of the first antenna 21 and the second antenna 22, S3,1 is the isolation curve of the first antenna 21 and the third antenna 23, S3,2 is the isolation curve of the second antenna 22 and the third antenna 23, and S3,3 is the return loss curve of the third antenna 23. As can be seen from fig. 17, the first antenna 21 and the third antenna 23 operate at about 2.6GHz with a loss of about-18 dB when operated in the B41/n41 frequency band, and the second antenna 22 operates at about 3.5GHz with a loss of about-20 dB when operated in the n78 frequency band. Moreover, as can be seen from the isolation curve, the isolation of the first antenna 21 (the third antenna 23) and the second antenna 22 in the B41/n41 frequency band is below-12 dB, the isolation in the n78 frequency band is below-20 dB, and the isolation is high. Therefore, the three-wire integrated antenna device provided by the embodiment of the application can improve the isolation degree of the antenna operation.

Further, referring to fig. 19, 20, and 21, the simulated current profiles when the first antenna 21 is excited, when the second antenna 22 is excited, and when the third antenna 23 is excited are respectively shown. Wherein, the operating frequency of the first antenna 21 and the third antenna 23 is 2.6GHz, and the operating frequency of the second antenna 22 is 3.5GHz. As shown in fig. 19, when the first antenna 21 is excited by the feed source, there is almost no coupling current on the second antenna 22 and the third antenna 23. As also shown in fig. 20, when the feed excitation is provided to the second antenna 22, there is little coupling current on the first antenna 21 and the third antenna 23, which means that the second antenna 22 has little effect on the first antenna 21 and the third antenna 23 when in operation. Similarly, as shown in fig. 21, when the third antenna 23 is operated, there is little influence on the first antenna 21 and the second antenna 22. The three simulation current distribution diagrams further illustrate that the three-wire common antenna device provided by the embodiment of the application has high isolation, the three antennas are not mutually affected when in operation, and the working stability and reliability of the antenna device are improved.

Further, in the embodiment of the present application, the first antenna 21 and the third antenna 23 may work at different working frequencies, so as to cover more communication frequency bands, and further increase communication performance. The tuning manner of the first antenna 21 and the third antenna 23 is not limited in the present application, for example, the first antenna 21 and the third antenna 23 may change the operating frequency by adjusting their own lengths, or the first antenna 21 and the third antenna 23 may change the operating frequency by providing a tuning device at the end of a conductor. As a more specific example, the antenna device in the embodiment of the present application may be configured such that the antenna conductor 213 of the first antenna 21 and the antenna conductor 233 of the third antenna 23 are different in length so as to operate at different frequencies. As is known from the properties of the first antenna 21 (the third antenna 23) described above, the first antenna 21 (the third antenna 23) can change the frequency of operation by changing the length of its own conductor, and the longer the length of the antenna, the lower the frequency of operation of the antenna.

Fig. 22 shows a specific structure of the three-wire co-body of the first antenna 21 and the third antenna 23 at different lengths L1 and L2. At this time, the first antenna 21 may operate in the B41/n41 band, the second antenna 22 may operate in the n78 band, and the third antenna 23 may operate in the B40/n40 band. The S parameter diagram operating under this structure is shown in fig. 23, S1,1 is the return loss curve of the first antenna 21, S2,2 is the return loss curve of the second antenna 22, S3,3 is the return loss curve of the third antenna 23, S2,1 is the isolation curve of the first antenna 21 and the second antenna 22, S3,2 is the isolation curve of the second antenna 22 and the third antenna 23, and S3,1 is the isolation curve of the first antenna 21 and the third antenna 23. It is known that the operating frequency of the first antenna 21 is about 2.6GHz, the operating frequency of the second antenna 22 is about 3.5GHz, and the operating frequency of the third antenna 23 is about 2.3GHz. As can be seen from the three isolation curves, when the three antennas work in the respective frequency bands, the isolation is below-12 dB, so that the three-wire common antenna device in the embodiment of the application has high isolation, and the antennas hardly interfere with each other when working.

Further, as shown in fig. 24, S1 is the operation efficiency curve of the first antenna 21, S2 is the operation efficiency curve of the second antenna 22, and S3 is the operation efficiency curve of the third antenna 23. It can be seen that when the three antennas operate in respective frequency bands, the efficiency can reach about 100%, i.e. the operating efficiency is about 0dB. Therefore, the three-wire integrated antenna device provided by the embodiment of the application can ensure that the three antennas can still achieve higher radiation efficiency in respective working frequency bands.

As can be seen from the above illustration and analysis, the three-wire co-body antenna device provided by the embodiment of the present application can work at three different communication frequency bands because the first antenna, the second antenna and the third antenna can work at different frequencies, for example, the antenna device can work together at different communication frequency bands of LTE/NR/GPS. The three-wire integrated antenna device not only saves the stacking space of the antenna and makes the structure of the antenna more compact, but also reduces the cost and manufacturing difficulty of the antenna device. Meanwhile, when the three antennas work in different modes, the isolation degree is very high, and the phenomenon of excessive coupling can not be generated. In addition, the antenna device with three antenna bodies can still keep higher working efficiency on the basis of realizing miniaturization.

Two more specific examples of the antenna device provided in the embodiment of the present application are given below with reference to fig. 25 and 26. It should be noted that the examples shown in fig. 25 and 26 are merely to aid one skilled in the art in understanding the embodiments of the present application, and are not intended to limit the embodiments of the present application to the specific values or specific scenarios illustrated. Various equivalent modifications or variations will be apparent to those skilled in the art from the examples given below, and such modifications or variations are intended to be within the scope of embodiments of the present application.

Referring to fig. 25, the antenna device includes a circuit board 20, a first antenna 21, a second antenna 22, and a third antenna 23. Wherein the circuit board 20 is a printed circuit board. From left to right, the first antenna 21, the second antenna 22 and the third antenna 23, respectively, as seen in fig. 25, the first antenna 21 includes a feed end 212, a feed point 211 and a ground end 214 extending outwardly from the circuit board 20, and an antenna conductor 213 connected to the feed end 212 and the ground end 214, the second antenna 22 includes a first branch 221, a second branch 222, a third branch 223 and a fourth branch 224, the first branch 221 and the second branch 222 extend outwardly from the circuit board 20, a gap between the third branch 223 and the fourth branch 224 forms an opening portion of the split ring resonator, the feed point 225 provides feed excitation to the second antenna 22 through a recess 226 in the circuit board 20, and the third antenna 23 includes a feed end 232, a feed point 231 and a ground end 234 extending outwardly from the circuit board 20, and an antenna conductor 233 connected to the feed end 232 of the third antenna 23 and the ground end 234 of the third antenna 23. It can be seen that the ground 214 of the first antenna 21 and the first branch 221 of the second antenna 22 are the same radiator, and the ground 234 of the third antenna 23 and the second branch 222 of the second antenna 22 are the same radiator.

Further, the open end of the second antenna 23 is loaded with a capacitive-inductive parallel circuit. The frequency of the second antenna can be changed by adjusting the capacitor C6 in the circuit, and the isolation of the antenna device can be further improved by increasing the inductor L6, so that the antenna device works more stably. Since the second antenna 22 can change the operating frequency of the second antenna 22 by changing the magnitude of the open end capacitance. Therefore, the second antenna 22 is not limited to the size of the antenna, and a state in which the antenna operates at a low frequency can be realized by controlling the operating frequency of the antenna with a large capacitance in a case where the size is small. It can be seen that the antenna device shown in fig. 25 can achieve miniaturization of the antenna device structure by operating the second antenna in a small size.

Meanwhile, the first antenna 21 and the third antenna 23 may change the efficiency of operation by changing their lengths.

Because the three antennas can respectively work in different frequency bands, the working high isolation can be realized, the influence of other antennas can not be received during the working, and the working efficiency of each antenna is ensured.

Fig. 26 is a substantially similar structure to the antenna arrangement of fig. 25, with the main difference being the different tuning of the three antennas. In fig. 26, the first antenna 21 and the third antenna 23 can adjust the operating frequency by loading the switching devices 215 and 235 at the ends 213 and 233, and the second antenna 22 can adjust the operating frequency by loading the variable capacitor C4 at the open end. Fig. 26 is substantially identical to the other structure and operation of the antenna assembly of fig. 25 and will not be described in detail herein for the sake of brevity.

Fig. 27 is a schematic structural diagram of an electronic device according to an embodiment of the present application, where an electronic device 400 shown in the drawing may include an antenna apparatus provided in any of the foregoing embodiments. The electronic device mentioned in the embodiment of the present application may be any type of electronic device having a wireless communication function. For example, the electronic device may be a portable mobile terminal or a handheld mobile terminal. The electronic device 400 provided by the embodiment of the application can realize the function of wireless communication through the antenna device.

It should be understood that in embodiments of the present application, "B corresponding to a" means that B is associated with a, from which B may be determined. It should also be understood that determining B from a does not mean determining B from a alone, but may also determine B from a and/or other information.

It should be understood that the term "and/or" is merely an association relationship describing the associated object, and means that three relationships may exist, for example, a and/or B, and that three cases, a alone, a and B together, and B alone, may exist. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

It should be understood that, in various embodiments of the present application, the sequence numbers of the foregoing processes do not mean the order of execution, and the order of execution of the processes should be determined by the functions and internal logic thereof, and should not constitute any limitation on the implementation process of the embodiments of the present application.

In the several embodiments provided in the present application, it should be understood that the disclosed system and apparatus may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

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

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

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, fiber optic, digital subscriber line (digital subscriber Line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be read by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., digital versatile disk (digital video disc, DVD)), or a semiconductor medium (e.g., solid State Disk (SSD)), etc.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An antenna device, comprising:

circuit boards;

a first antenna, the first antenna being an inverted-F antenna, the first antenna comprising a feeding end and a grounding end extending outward from the circuit board, and an antenna conductor connected to the feeding end and the grounding end;

a second antenna, the second antenna being an antenna based on a split ring resonator, the second antenna comprising a first branch, a second branch, a third branch, and a fourth branch, the first branch and the second branch extending outward from the circuit board, and a gap between the third branch and the fourth branch forming an opening portion of the split ring resonator;

The ground end of the first antenna and the first branch are the same radiator.

2. The antenna device according to claim 1, further comprising:

A first capacitor, one end of the first capacitor is connected to the third branch, and the other end of the first capacitor is connected to the fourth branch.

The antenna device according to claim 2 , wherein the first capacitor is a variable capacitor.

4. The antenna device according to claim 3, further comprising:

A tuning device, one end of which is connected to the end of the antenna conductor, and the other end of which is connected to the circuit board, and the tuning device is used to tune the first antenna.

5. The antenna device according to claim 2, further comprising:

A first inductor is connected in parallel with the first capacitor.

6. The antenna device according to claim 1, further comprising:

a third antenna, the third antenna being an inverted-F antenna, the third antenna comprising a feeding end and a grounding end extending outward from the circuit board, and an antenna conductor connected to the feeding end of the third antenna and the grounding end of the third antenna;

The ground end of the third antenna and the second branch are the same radiator.

7 . The antenna device according to claim 6 , wherein the antenna conductor of the first antenna and the antenna conductor of the third antenna have different lengths.

8. The antenna device according to claim 1, wherein the circuit board comprises:

A first groove is located between the first branch and the second branch, and the circuit board provides feed source excitation to the second antenna through the first groove.

9 . The antenna device according to claim 1 , wherein the first antenna and the second antenna have different operating frequencies.

10. An electronic device, comprising:

The antenna device according to any one of claims 1 to 9.