CN110649373A - An antenna structure and terminal - Google Patents

Abstract

The invention provides an antenna structure and a terminal. The antenna structure includes: a first radiating arm, the first radiating arm is electrically connected to a first ground terminal; a first feed source, a first antenna matching circuit and a first inductance, a first The first end of the inductor is electrically connected to the first radiation arm, the second end of the first inductor is electrically connected to the first antenna matching circuit, and the first antenna matching circuit is electrically connected to the first feed; the second radiation arm and the second antenna a matching circuit, the second antenna matching circuit is connected between the second radiation arm and the second ground terminal, the second radiation arm is electrically connected with the first transmission line, and the first transmission line is a transmission line connecting the first inductor and the first antenna matching circuit; Wherein, the length of the first radiation arm is greater than the length of the second radiation arm. Therefore, the solution of the present invention solves the problems of poor efficiency and bandwidth of the antenna expanded by adding a switching circuit on the basis of the original antenna.

Description

An antenna structure and terminal

technical field

The present invention relates to the field of communication technologies, and in particular, to an antenna structure and a terminal.

Background technique

At present, the metal texture of the terminal has become the mainstream, and the proportion of the display screen has gradually increased, and the design space of the antenna resonator arm is not getting smaller and smaller. Especially for metal-shaped terminals, the shape of the antenna resonating arm is extremely simple. Unlike FPC (flexible printed circuit board) or LDS (laser forming technology) antennas, the radiating arm can have many variations.

Among them, the metal-shaped mobile terminal antenna is designed under the circumstance of limited space and simple-shaped resonant arm. By adding a tuning switch, it can switch out low frequency (700MHz, 850MHz, 900MHz) and high frequency (1710MHz-2690MHz), but In the existing limited environment of the whole machine, I want to widen the antenna bandwidth to support the 5G frequency band N78 (3300MHz-3800MHz)/N79 (4400MHz-5000MHz). Both the efficiency and bandwidth are poor and cannot meet the needs of users.

For example, increasing the 5G frequency band in the medium and high frequency radiation arm can only be solved by increasing the number of switching channels, but limited by the length of the medium and high frequency radiation arm itself, when it is adjusted to 3.5GHz or even 4.7GHz through matching, the antenna radiation efficiency and The bandwidth is poor, and also affects the performance of the existing IF. At the same time, the frequency doubling of the low frequency will also fall in the range of 3GHz-5GHz, and the isolation between the low frequency antenna and the medium and high frequency antenna will be very poor, which will also lead to poor performance in the 5G frequency band.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide an antenna structure and a terminal to solve the problems of poor antenna efficiency and bandwidth expanded by adding a switch circuit on the basis of the original antenna.

In a first aspect, an embodiment of the present invention provides an antenna structure, including:

a first radiation arm, the first radiation arm is electrically connected to the first ground terminal;

a first feed source, a first antenna matching circuit and a first inductor, the first end of the first inductor is electrically connected to the first radiation arm, and the second end of the first inductor is matched with the first antenna a circuit is electrically connected, and the first antenna matching circuit is electrically connected to the first feed;

A second radiating arm and a second antenna matching circuit, the second antenna matching circuit is connected between the second radiating arm and the second ground terminal, the second radiating arm is electrically connected to the first transmission line, the first A transmission line is a transmission line connecting the first inductor and the first antenna matching circuit;

Wherein, the length of the first radiation arm is greater than the length of the second radiation arm.

In a second aspect, an embodiment of the present invention provides a terminal, including the above-mentioned antenna structure.

The beneficial effects of the embodiments of the present invention are:

In the embodiment of the present invention, a first inductance is set between the first radiating arm and the first antenna matching circuit, the second radiating arm is connected on the transmission line between the first inductance and the first antenna matching circuit, and the second radiating arm is connected to the transmission line between the first inductance and the first antenna matching circuit. A second antenna matching circuit is set between the arm and the ground terminal, so that the first radiating arm and the second radiating arm share a feed source, which not only realizes the expansion of the working frequency band of the second radiating arm from the original working frequency band of the first radiating arm , and the signal coupled to the first radiation arm is blocked from entering the second radiation arm through the first inductance, thereby blocking the influence of the signal coupled to the first radiation arm on the working frequency band of the extended second radiation arm, The problem of poor efficiency and bandwidth of the antenna expanded by adding a switching circuit on the basis of the original antenna is solved.

Description of drawings

FIG. 1 shows one of the schematic circuit diagrams of the antenna structure according to the embodiment of the present invention;

FIG. 2 shows the second schematic diagram of the circuit principle of the antenna structure according to the embodiment of the present invention;

FIG. 3 shows the third schematic diagram of the circuit principle of the antenna structure according to the embodiment of the present invention;

In the figure: 1, the first feed source; 2, the first radiation arm; 7, the first inductor; 9, the first antenna matching circuit; 8, the second radiation arm; 10, the second antenna matching circuit; 5, the first three radiating arms; 4. the second feed; 3. the third antenna matching circuit; 11, the fourth antenna matching circuit; 12, the fifth antenna matching circuit; 6, the sixth antenna matching circuit; K1, the first switch; K2, the second switch; K3, the third switch; K4, the fourth switch.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

An embodiment of the present invention provides an antenna structure, as shown in FIGS. 1 to 3 , including:

a first radiation arm 2, the first radiation arm 2 is electrically connected to the first ground terminal;

The first feed source 1 , the first antenna matching circuit 9 and the first inductor 7 , the first end of the first inductor 7 is electrically connected to the first radiation arm 2 , and the second end of the first inductor 7 is electrically connected to the first radiating arm 2 . The first antenna matching circuit 9 is electrically connected, and the first antenna matching circuit 9 is electrically connected to the first feed 1;

The second radiating arm 8 and the second antenna matching circuit 10, the second antenna matching circuit 10 is connected between the second radiating arm 8 and the second ground terminal, the second radiating arm 8 is electrically connected to the first transmission line connection, the first transmission line is the transmission line connecting the first inductor 7 and the first antenna matching circuit 9;

Wherein, the length of the first radiation arm 2 is greater than the length of the second radiation arm 8 .

In addition, the first radiating arm 2 works in a first preset frequency band, the second radiating arm 8 works in a second preset frequency band, and the first feed 1 includes a signal of the first preset frequency band and the signal of the second preset frequency band. The length of the first radiation arm 2 is set according to the signal wavelength of the first preset frequency band, and the second radiation arm 8 is set according to the signal wavelength of the second preset frequency band. For example, the length of the first radiation arm 2 may be 60 mm.

It can be seen from the above that in the embodiment of the present invention, the first inductance 7 is arranged between the first radiating arm 2 and the first antenna matching circuit 9 and is connected on the transmission line between the first inductance 7 and the first antenna matching circuit 9 For the second radiation arm 8, a second antenna matching circuit 10 is arranged between the second radiation arm 8 and the ground terminal, so that the first radiation arm 2 and the second radiation arm 8 share a feed source, which not only realizes the original first radiation The working frequency band of the second radiating arm 8 is extended from the working frequency band of the arm 2, and the signal coupled to the first radiating arm 2 is blocked from entering the second radiating arm 8 through the first inductance 7, thereby blocking the coupling to the second radiating arm 8. The influence of the signal on the first radiating arm 2 on the operating frequency band of the extended second radiating arm 8 solves the problem of poor efficiency and bandwidth of the antenna expanded by adding a switch circuit on the basis of the original antenna.

That is, in the embodiment of the present invention, on the basis of the first preset frequency band in which the first radiating arm 2 works, the second preset frequency band in which the second radiating arm 8 works is expanded, and the coupling to the first radiating arm 2 is blocked. The signal on the second preset frequency band interferes with the signal of the second preset frequency band.

In addition, the antenna bandwidth and efficiency can also be improved by increasing the distance between the second radiation arm 8 and the second ground terminal, that is, by increasing the antenna clearance of the second radiation arm 8 .

Optionally, the first preset frequency band is a low frequency band (700MHz-800MHz, 824MHz-894MHz, 880MHz-960MHz), and the second preset frequency band is a 5G frequency band (N78, that is, 3300MHz-3800MHz)/N79, that is, 4400MHz-5000MHz). In this case, in the embodiment of the present invention, a second antenna radiating arm is added between the low-frequency feed source (ie, the first feed source 1 ) and the first inductance 7 to adjust the resonance of the 5G frequency band, and by connecting the first radiating arm 2 and A first inductance 7 is added between the first antenna matching circuits 9, so that when the signal of the high-frequency antenna is coupled from the first radiating arm 2 to the first inductance 7, the first inductance 7 blocks the high-frequency signal and prevents the high-frequency signal from entering The second radiation arm 8 . In a limited environment, the antenna efficiency bandwidth is expanded, and the 4G frequency band and 5G frequency band common antenna design is realized, which improves the isolation between the antennas.

Optionally, the inductance value of the first inductance 7 is greater than or equal to 10nH.

Optionally, the second radiation arm 8 is electrically connected to the first transmission line through elastic sheets or conductive foam. Wherein, it can be understood that the connection manner between the second radiation arm 8 and the first transmission line is not limited to this.

Optionally, the second radiating arm 8 is a planar F antenna, or a planar inverted-F antenna, or a loop antenna, or a flexible printed circuit board antenna, or a laser formed antenna, or is formed of a metal piece. Wherein, it can be understood that the specific arrangement form of the second radiation arm 8 is not limited to this.

Optionally, as shown in Figure 1, it also includes:

at least one third antenna matching circuit 3, the at least one third antenna matching circuit 3 is electrically connected to the first radiating arm 2 respectively;

a first switch K1, the first switch K1 is connected between the at least one third antenna matching circuit 3 and the third ground terminal;

A path between the third antenna matching circuit 3 and the third ground terminal is turned on through the first switch K1.

The first switch K1 conducts the paths between different third antenna matching circuits 3 and the third ground terminal, and the inductive or capacitive change of the first antenna radiating arm through the third antenna matching circuit 3 to the third ground terminal changes , so that the antenna resonance of the first preset frequency band can be adjusted.

Specifically, if the first preset frequency band is a low frequency frequency band, if the first antenna matching circuit 9 matches the 700MHz-800MHz frequency band, then the first switch K1 can be used to turn on different third antenna matching circuits 3 to resonate The working frequency band is increased to 824MHz-894MHZ or 880MHz-960MHz; if the first antenna matching circuit 9 matches the 880MHz-960MHz frequency band, then the different third antenna matching circuits 3 can be turned on through the first switch K1 to resonate The working frequency band is pulled down to 824MHz-894MHZ or 700MHz-800MHz. Wherein, when the third antenna matching circuit 3 is a capacitor, the resonant operating frequency band can be pulled down, and when the third antenna matching circuit 3 is an inductor, the resonant operating frequency band can be increased.

Optionally, as shown in Figure 2, it also includes:

At least one fourth antenna matching circuit 11, the target circuit is electrically connected to the second transmission line, and other antenna matching circuits other than the target circuit in the at least one fourth antenna matching circuit 11 are electrically connected to the first radiating arm 2. connection, the target circuit is one of the at least one fourth antenna matching circuit 11, and the second transmission line is the transmission line connecting the second radiating arm 8 and the second antenna matching circuit 10;

a second switch K2, the second switch K2 is connected between the at least one channel of the fourth antenna matching circuit 11 and the fourth ground terminal;

The second switch K2 is used to switch on a path between the fourth antenna matching circuit 11 and the fourth ground terminal.

That is, among the plurality of fourth antenna matching circuits 11 connected to the second switch K2, one channel (ie, the target circuit) may be connected to the transmission line between the second radiating arm 8 and the second antenna matching circuit 10, so that the first When the switch K2 turns on or off the path between the target circuit and the fourth ground terminal, the resonant frequency band of the second radiating arm 8 can be adjusted. For example, when the second preset frequency band of the second radiating arm 8 is the 5G frequency band, switching between the N78 frequency band and the N78 frequency band can be realized by turning on or off the path between the target circuit and the fourth ground terminal.

In addition, if other antenna matching circuits except the target circuit among the plurality of fourth antenna matching circuits 11 are electrically connected to the first radiating arm 2, any one of these antenna matching circuits can be turned on through the second switch K2, The adjustment of the resonance frequency band of the first radiation arm 2 is realized.

In addition, the antenna matching circuit for adjusting the resonance frequency band of the first radiation arm 2 and the antenna matching circuit for adjusting the resonance frequency band of the second radiation arm 8 are connected to a switch, that is, a switch is shared, which can save components and reduce the Circuit layout space. That is, by multiplexing the tuning switches of the first radiating arm 2, the frequency band that can be covered by the antenna is increased, and the bandwidth of the antenna is further expanded without increasing the cost.

Optionally, as shown in Figure 3, it also includes:

a fifth antenna matching circuit 12, the fifth antenna matching circuit 12 is electrically connected with a second transmission line, and the second transmission line is a transmission line connecting the second radiating arm 8 and the second antenna matching circuit 10;

a third switch K3, the third switch K3 is connected between the fifth antenna matching circuit 12 and the fifth ground terminal;

The path between the fifth antenna matching circuit 12 and the fifth ground terminal is switched on or off through the second switch K2.

That is, an antenna matching circuit and a switch can be provided separately for the second radiating arm 8 . Wherein, when the third switch K3 turns on or off the path between the fifth antenna matching circuit 12 and the fifth ground terminal, the resonant frequency band of the second radiating arm 8 can be adjusted. For example, when the second preset frequency band of the second radiation arm 8 is the 5G frequency band, the connection between the N78 frequency band and the N78 frequency band can be realized by turning on or off the path between the fifth antenna matching circuit 12 and the fifth ground terminal. switch.

Optionally, as shown in Figures 1-3, it also includes:

the third radiation arm 5, the third radiation arm 5 is electrically connected to the sixth ground terminal;

The second feed source 4, the second feed source 4 is electrically connected to the third radiation arm 5;

at least one sixth antenna matching circuit 6, the at least one sixth antenna matching circuit 6 is respectively electrically connected to the third radiating arm 5;

a fourth switch K4, the fourth switch K4 is connected between the at least one sixth antenna matching circuit 6 and the sixth ground terminal;

The resonant frequency band of the third radiating arm 5 can be adjusted by turning on a path between the sixth antenna matching circuit 6 and the sixth ground terminal through the third switch K3.

In addition, the third radiation arm 5 operates in a third preset frequency band. The length of the third radiation arm 5 is set according to the signal wavelength of the third preset frequency band. For example, the length of the third radiating arm 5 may be 22 mm. Optionally, the length of the third radiation arm 5 is smaller than the length of the first radiation arm 2 and greater than the length of the second radiation arm 8 .

Optionally, the third preset frequency band is a high frequency band (1710MHz-2690MHz).

Optionally, the first radiation arm 2 is composed of a first metal part, and the third radiation arm 5 is composed of a second metal part; wherein, an opening is formed on a metal part to form the first metal part and the the second metal part. For example, as shown in FIG. 1 to FIG. 3 , the first radiation arm 2 and the third radiation arm 5 are formed by a metal piece with a non-metallic material filling the gap.

Optionally, the distance between the first feed source 1 and the grounded connection end of the first radiation arm 2 is less than a first preset value, and the distance between the first feed source 1 and the opening is The distance is greater than the second preset value. That is, the first feed source 1 is close to the ground end of the first resonant arm and is far from the open end, thereby further improving the performance of the antenna.

Optionally, the distance between the connection end of the third antenna matching circuit 3 and the first radiation arm 2 and the switch end is less than a third preset value, and the distance between the third antenna matching circuit 3 and the first feed source 1 The distance is greater than the fourth preset value. That is, the third antenna matching circuit 3 is arranged close to the open end and is far away from the first feed source 1, thereby further improving the antenna performance.

Optionally, the distance between the second feed source 4 and the opening is less than the fifth preset value, and the distance between the sixth antenna matching circuit 6 and the second feed source 4 is less than the sixth preset value, that is, the second The feed source 4 is close to the open end, and the sixth antenna matching circuit 6 is arranged at the feed position, thereby further improving the performance of the antenna.

An embodiment of the present invention further provides a terminal including the above-mentioned antenna structure.

In the above-mentioned antenna structure, a first inductance 7 is arranged between the first radiating arm 2 and the first antenna matching circuit 9 , and a second inductance is connected on the transmission line between the first inductance 7 and the first antenna matching circuit 9 . For the radiation arm 8, a second antenna matching circuit 10 is arranged between the second radiation arm 8 and the ground terminal, so that the first radiation arm 2 and the second radiation arm 8 share a feed source, which not only realizes the original first radiation arm 2 The working frequency band of the second radiating arm 8 is expanded from the working frequency band of the first radiating arm 8, and the signal coupled to the first radiating arm 2 is blocked from entering the second radiating arm 8 through the first inductance 7, thereby blocking the coupling to the first radiation arm 8. The influence of the signal on the arm 2 on the working frequency band of the expanded second radiating arm 8 solves the problem of poor efficiency and bandwidth of the antenna expanded by adding a switching circuit on the basis of the original antenna. Therefore, the embodiment of the present invention terminal, it can work on more frequency bands.

The above are the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. It should be regarded as the protection scope of the present invention.

Claims (10)

1. an antenna structure, is characterized in that, comprises: a first radiation arm, the first radiation arm is electrically connected to the first ground terminal; a first feed source, a first antenna matching circuit and a first inductor, the first end of the first inductor is electrically connected to the first radiation arm, and the second end of the first inductor is matched with the first antenna a circuit is electrically connected, and the first antenna matching circuit is electrically connected to the first feed; A second radiating arm and a second antenna matching circuit, the second antenna matching circuit is connected between the second radiating arm and the second ground terminal, the second radiating arm is electrically connected to the first transmission line, the first A transmission line is a transmission line connecting the first inductor and the first antenna matching circuit; Wherein, the length of the first radiation arm is greater than the length of the second radiation arm. 2. The antenna structure according to claim 1, further comprising: at least one third antenna matching circuit, the at least one third antenna matching circuit is respectively electrically connected to the first radiation arm; a first switch, the first switch is connected between the at least one channel of the third antenna matching circuit and the third ground terminal; Wherein, a path between the third antenna matching circuit and the third ground terminal is turned on through the first switch switch. 3. The antenna structure according to claim 1, further comprising: At least one fourth antenna matching circuit, the target circuit is electrically connected to the second transmission line, and other antenna matching circuits except the target circuit in the at least one fourth antenna matching circuit are electrically connected to the first radiating arm, so The target circuit is one of the at least one fourth antenna matching circuit, and the second transmission line is a transmission line connecting the second radiation arm and the second antenna matching circuit; a second switch, the second switch is connected between the at least one channel of the fourth antenna matching circuit and the fourth ground terminal; Wherein, a path between the fourth antenna matching circuit and the fourth ground terminal is turned on through the second switch switch. 4. The antenna structure of claim 1, further comprising: a fifth antenna matching circuit, the fifth antenna matching circuit is electrically connected with a second transmission line, and the second transmission line is a transmission line connecting the second radiating arm and the second antenna matching circuit; a third switch, the third switch is connected between the fifth antenna matching circuit and a fifth ground terminal; Wherein, the path between the fifth antenna matching circuit and the fifth ground terminal is turned on or off through the second switch switch. 5. The antenna structure of claim 1, further comprising: a third radiation arm, the third radiation arm is electrically connected to the sixth ground terminal; a second feed source, the second feed source is electrically connected to the third radiation arm; at least one sixth antenna matching circuit, the at least one sixth antenna matching circuit is respectively electrically connected to the third radiating arm; a fourth switch, the fourth switch is connected between the at least one sixth antenna matching circuit and the sixth ground terminal; Wherein, a path between the sixth antenna matching circuit and the sixth ground terminal is turned on through the third switch switch. 6. The antenna structure according to claim 5, wherein the first radiating arm is composed of a first metal part, and the third radiating arm is composed of a second metal part; Wherein, an opening is formed on a metal part to form the first metal part and the second metal part. 7 . The antenna structure according to claim 1 , wherein the inductance value of the first inductor is greater than or equal to 10 nH. 8 . 8 . The antenna structure according to claim 1 , wherein the second radiating arm is electrically connected to the first transmission line through an elastic sheet or conductive foam. 9 . 9 . The antenna structure according to claim 1 , wherein the second radiating arm is a planar F antenna, or a planar inverted-F antenna, or a loop antenna, or a flexible printed circuit board antenna, or a laser formed antenna, or Consists of metal parts. 10. A terminal, comprising the antenna structure according to any one of claims 1 to 9.

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