WO2016045459A1

WO2016045459A1 - Antenna device for mobile terminal, and mobile terminal

Info

Publication number: WO2016045459A1
Application number: PCT/CN2015/086499
Authority: WO
Inventors: 陈玉稳
Original assignee: 维沃移动通信有限公司
Priority date: 2014-09-22
Filing date: 2015-08-10
Publication date: 2016-03-31
Also published as: CN105281020B; CN105281020A

Abstract

This disclosure provides is an antenna device for a mobile terminal, comprising: a metal frame on one side of which at least one breaking point is disposed, and an excitation sheet connected to a radio frequency front end, wherein the breaking point partitions the metal frame into a first metal arm and a second metal arm, the first metal arm is shorter than the second metal arm, the excitation sheet is coupled with the first metal arm, and the second metal arm is coupled with the excitation sheet through the first metal arm. Meanwhile, a mobile terminal using the antenna device is provided.

Description

Mobile terminal antenna device and mobile terminal

Cross-reference to related applications

The present application claims priority to Chinese Patent Application No. 201410487769.0, filed on Sep. 22, 2014, the entire content of

Technical field

The present disclosure relates to the field of electronic technologies, and in particular, to a metal frame antenna device.

Background technique

Compared with mobile terminals with ordinary plastic casings, users tend to prefer metal-like mobile terminals, and the resulting antenna signal problem has always been a problem that plagues the industry.

At present, there are three effective solutions: the direct-feed side-break multi-point method, the direct-feed bottom-break multi-point method, and the coupled bottom-side multi-point method. Each of these solutions has several specific implementations.

An existing coupled feed antenna device for a mobile terminal adopts an antenna coupling metal frame bottom edge breakpoint mode; the antenna branch 1 is coupled with a longer first metal arm to generate a low frequency resonance, and the antenna branch is second and The two metal arms generate high frequency resonance. If the breakpoint position is shifted to the right such that the first metal arm is shorter than the second metal arm (as shown in Figure 1B), the low frequency bandwidth of the antenna is very narrow. As shown in Figure 1B, the breakpoint is shifted to the right. As shown in FIG. 1C, when the breakpoint is on the right side, the low frequency bandwidth is much narrower than the original bandwidth, and the high frequency bandwidth becomes better. In addition, the coupling of the existing USB module and the metal arm can enhance the communication performance of the mobile terminal at high frequencies when using USB charging. According to the experiment, the performance of the low frequency band is degraded when using USB charging.

Summary of the invention

In an aspect of the present disclosure, a mobile terminal antenna device includes: a metal frame, one side of the metal frame is provided with at least one break point; and is connected to An excitation piece of the RF front end, the break point separating the metal frame into a first metal arm and a second metal arm, the first metal arm being shorter than the second metal arm, the excitation piece and the first gold The arm is coupled, and the second metal arm is coupled to the excitation piece by a first metal arm.

Another aspect of the embodiments of the present disclosure provides a mobile terminal, including a display screen, a main board, a USB module, a speaker, an antenna, and an excitation piece connected to the RF front end, and at least one side of the metal frame of the antenna is provided a breakpoint separating the metal frame into a first metal arm and a second metal arm, the first metal arm being shorter than the second metal arm, the excitation piece being coupled to the first metal arm, A second metal arm is coupled to the energizing plate by a first metal arm.

The mobile terminal antenna device and the mobile terminal provided by the embodiments of the present disclosure have the following advantages compared with the prior art:

1. The low frequency resonance generated by the second metal arm is coupled to the excitation piece through the first metal arm. Although the first metal arm mainly generates high frequency resonance, it also contributes to the low frequency resonance, and is only coupled to the long metal arm compared to the excitation piece. Scheme with better low frequency bandwidth;

2. The second metal arm generates both low frequency resonance and high frequency secondary resonance, which contributes to the low frequency bandwidth and contributes to the high frequency bandwidth.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present disclosure. Other drawings may also be obtained from those of ordinary skill in the art in light of the inventive work.

1A and 1B are schematic structural views of a prior art;

1C is a measured S parameter diagram of a prior art antenna;

2 is a schematic structural diagram of Embodiment 1 of a mobile terminal antenna device according to the present disclosure;

3 is a low frequency impedance chart of Embodiment 1 of the mobile terminal antenna device according to the present disclosure;

4 is a high frequency impedance chart of the first embodiment of the mobile terminal antenna device according to the present disclosure;

5 is an equivalent capacitance parameter diagram of the L string C of the mobile terminal antenna device in different frequency bands according to the present disclosure;

6 is an antenna measured S parameter diagram of the first embodiment of the mobile terminal antenna device according to the present disclosure;

FIG. 7 is a schematic structural diagram of Embodiment 2 of a mobile terminal antenna device according to the present disclosure;

FIG. 8 is a schematic structural diagram of Embodiment 3 of a mobile terminal antenna device according to the present disclosure;

FIG. 9 is a parameter diagram of an antenna efficiency improvement of a mobile terminal according to the present disclosure when using USB charging.

detailed description

The present disclosure will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the disclosure and are not intended to limit the disclosure.

In the description of the present disclosure, it is to be understood that the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", The orientation or positional relationship of the indications "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings. The present disclosure and the simplifications of the disclosure are merely intended to be illustrative, and not to be construed as limiting the scope of the disclosure. In the description of the present disclosure, "a plurality of" means two or more unless otherwise stated.

In the description of the present disclosure, it should be noted that the terms "installation", "connected", and "connected" are to be understood broadly, and may be fixed or detachable, for example, unless otherwise explicitly defined and defined. Connected, or integrally connected; can be mechanical or electrical; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of the two components. The specific meanings of the above terms in the present disclosure can be understood in the specific circumstances by those skilled in the art.

When the embodiments of the present disclosure refer to ordinal numbers such as "first", "second" and the like, unless it is intended to express the order of the context, it should be understood as merely distinguishing.

Example 1

Please refer to FIG. 2, which is a specific embodiment of an antenna device of a mobile terminal according to the present disclosure.

The mobile terminal antenna device of this embodiment includes: a main board or display metal bracket 11; a metal frame 12, one side of the metal frame 12 is provided with at least one break point; and an excitation piece connected to the RF front end.

The breakpoint divides the metal frame into a first metal arm 1 and a second metal arm 2; the first metal arm 1 is shorter than the second metal arm 2, and the excitation piece is coupled to the first metal arm 1 Second metal arm 2 is coupled to the excitation piece by a first metal arm 1.

The excitation piece comprises a feeding leg 8 connected to the front end of the radio frequency, an antenna piece 3, a plurality of lumped coupling elements 4, 5 between the antenna piece and the first metal arm, and a lumped between the antenna piece and the main board ground. Elements 6, 7. The antenna piece is located inside the first metal arm, between the metal arm and the main board.

The lumped coupling elements 4, 5 may be a capacitance of 0.2-3 pF, or a series of capacitors (inductance and capacitance) equivalent to a low frequency of 1-3 pF and a high frequency of 0.2-1.5 pF.

A matching network can be added at the feed pin 8 to further optimize the antenna impedance bandwidth. As shown in Figure 3, the low impedance of the original antenna and the impedance of the string 2pF capacitor are just right. As shown in Figure 4, the high-frequency impedance of the original antenna and the impedance after the string of 1 pF are just right.

The next step is to construct a series network that varies with frequency, so that it has a low-frequency equivalent capacitance of about 2pF and a high-frequency equivalent capacitance of about 1pF. The component values shown in Figure 5 just do this. The network topology can also be changed to a capacitor string (capacitor and inductor). For different antenna structure sizes, the required series network with frequency changes varies slightly and needs to be properly adjusted.

The first metal arm can generate high frequency resonance, and the second metal arm can generate low frequency resonance and high frequency secondary resonance.

The first metal arm can generate a high frequency resonant frequency coupled to the excitation sheet, and the second metal arm can generate a high frequency secondary resonance coupled to the first metal arm and then coupled to the excitation sheet.

The second metal arm may be coupled to the excitation piece by a first metal arm, the second metal arm may generate a low frequency resonance, coupled to the first metal arm, and the first metal arm is coupled to the excitation piece to cause the excitation piece to be generated Low frequency resonance.

In this embodiment, a lumped element can be disposed between the second metal arm and the main board to facilitate tuning of the high frequency secondary resonance frequency.

In this embodiment, the coupling is coupled by capacitive coupling or by mutual proximity between the antenna sheet and the metal arm.

FIG. 6 is a measured S parameter diagram of the antenna shown in FIG. 2, and it can be seen that the high and low frequency bandwidths of the antenna are good.

The advantages of this embodiment are:

Example 2

Please refer to FIG. 7 , which is a schematic structural diagram of another specific embodiment of an antenna apparatus of a mobile terminal according to the present disclosure.

Different from Embodiment 1, the antenna sheet is directly coupled to the first metal arm, and the antenna sheet is connected to the main board in an optimized shape without paralleling the lumped elements to the main board. The use of lumped elements can effectively simplify the antenna design, and has the beneficial effect of saving antenna layout space and reducing antenna manufacturing cost.

Example 3

Please refer to FIG. 8 , which is a schematic structural diagram of another embodiment of the antenna device according to the present disclosure.

Different from Embodiment 1 and Embodiment 2, the first metal arm can use the grounded second antenna sheet 10, and the second metal arm can be replaced with the grounded third antenna sheet 20. This embodiment can adopt the technology of the present disclosure. The advantage is applied to a non-metal frame mobile terminal, so that the mobile terminal antenna device according to the embodiment of the present disclosure has a wider application range.

Example 4

The embodiment of the present disclosure further provides a mobile terminal, including a display screen, a main board, a USB module, a speaker, an antenna, and an excitation piece connected to the RF front end, and at least one break point is disposed on one side of the metal frame of the antenna. Destroying the metal frame into a first metal arm and a second metal arm, the first metal arm being shorter than the second metal arm, the excitation piece being coupled to the first metal arm, the second The metal arm is coupled to the energizing plate by a first metal arm.

FIG. 9 illustrates a case where the antenna efficiency of the mobile terminal of the embodiment of the present disclosure is increased when using USB charging.

The embodiments of the present disclosure overcome the technical drawback that the communication performance of the mobile terminal at the low frequency is degraded when using USB charging, and can ensure that the call performance of the high and low frequency bands is in a better state when using USB charging.

The above is a further detailed description of the present disclosure in conjunction with the specific embodiments, and the specific embodiments are not limited to the description. For example, the position of each breakpoint of the metal frame, the position of the first ground point and the second connection point, and the length of each coupling branch can be freely adjusted to optimize the antenna under the premise of understanding the intention of the present disclosure. The specific embodiments of the present disclosure are not limited to the above examples, and the specific embodiments may be made in the specific implementation process of the present disclosure, without departing from the scope of the present disclosure. There are a number of deductions or optimizations that should be considered as falling within the scope of this disclosure.

Claims

A mobile terminal antenna device includes: a metal frame having at least one break point on one side of the metal frame; and an excitation piece connected to the RF front end, wherein the break point separates the metal frame into the first metal arm And a second metal arm, the first metal arm being shorter than the second metal arm, the excitation piece being coupled to the first metal arm, and the second metal arm being coupled to the excitation piece by a first metal arm.
The mobile terminal antenna device according to claim 1, wherein said first metal arm generates high frequency resonance, and said second metal arm generates low frequency resonance and high frequency secondary resonance.
The mobile terminal antenna device according to claim 1, wherein the excitation piece is coupled to the first metal arm, and the second metal arm is coupled to the excitation piece by a first metal arm, comprising:

The first metal arm produces a high frequency resonant frequency coupled to the excitation sheet, the second metal arm producing a high frequency secondary resonance coupled to the first metal arm and then coupled to the excitation sheet.
The mobile terminal antenna device according to claim 1, wherein the coupling of the second metal arm to the excitation piece by the first metal arm comprises:

The second metal arm produces a low frequency resonance coupled to the first metal arm, the first metal arm being coupled to the excitation plate to cause the excitation plate to produce a low frequency resonance.
The mobile terminal antenna device according to any one of claims 1 to 4, wherein the coupling is coupled close to each other or across a capacitive element.
The mobile terminal antenna device according to claim 1, wherein the first metal arm and the second metal arm are antenna sheets.
A mobile terminal includes a display screen, a main board, a USB module, a speaker, an antenna, and an excitation piece connected to the RF front end, wherein at least one break point is provided on one side of the metal frame of the antenna, the break point Separating the metal frame into a first metal arm and a second metal arm, the first metal arm being shorter than the second metal arm, the excitation piece being coupled to the first metal arm, and the second metal arm passing the first A metal arm is coupled to the excitation piece.