WO2019084837A1

WO2019084837A1 - Antenna for mobile terminal, and mobile terminal having same

Info

Publication number: WO2019084837A1
Application number: PCT/CN2017/108904
Authority: WO
Inventors: 吕伟; 阮勇; 胡澈; 章富洪
Original assignee: 深圳传音制造有限公司
Priority date: 2017-11-01
Filing date: 2017-11-01
Publication date: 2019-05-09
Also published as: CN111295799B; CN111295799A

Abstract

The present invention provides an antenna for a mobile terminal, and a mobile terminal having the same. The antenna comprises a radiator, a feed terminal, and a feed circuit connected to the radiator and the feed terminal. The antenna further comprises a switch comprising a fixed terminal connected to the radiator, a ground terminal, and at least two free terminals, the switch switching the connection of the fixed terminal to any one the free terminals; one or more matching units, each of the matching units having a first end connected to one of the free terminals, and all of the matching units having a second end connected in parallel and then connected to the feed circuit; and a ground matching unit connected in series between the radiator and the ground terminal. The technical solution of the present invention reduces loss of signal reception to improve antenna performance. The shared components of the feed circuit are placed at a front end of the switch in order to reduce costs of the components, and to enhance antenna capabilities by optimizing performance within a single frequency band.

Description

Antenna for mobile terminal and mobile terminal having the same

Technical field

The present invention relates to the field of antennas, and in particular, to an antenna for a mobile terminal and a mobile terminal having the same.

Background technique

Nowadays, with the development of communication technology, 2G, 3G, 4G, WIFI, and GPS networks coexist. In order to be compatible with different networks, the antenna of mobile devices needs to be able to work in multiple frequency bands. In the field of mobile terminal devices, the design environment of the antenna is very complicated, the space is limited, and it is necessary to consider sharing the spatial structure with other functional components. One of the limitations is that simply designing any of the described antennas does not cover all of the required frequency bands. In order to meet the needs of working in multiple frequency bands, it is necessary to design multiple antenna elements and perform full frequency band on the antennas. test. The antenna comprises a feeding circuit, and the feeding circuit is composed of components such as a resistor, a capacitor and an inductor. During the testing process, it is necessary to find a parameter of the feeding circuit with the best performance, that is, find a set of resistors, capacitors and inductors. The parameters match the operating frequency band of the antenna. The method adopted by the prior art is to use a switch to select different feed circuits to work together, and select corresponding signal channels according to different frequency bands of the received wireless signals to achieve optimal antenna performance. However, using the switch to improve the antenna performance still has the following problems:

1. The received signal passes through the feeding circuit after the switching switch, and the signal loss is large;

2. Need to design multiple sets of feeding circuits, occupying more space and increasing costs.

Therefore, it is necessary to design an antenna suitable for a mobile terminal, which can reduce the loss of the received signal and reduce the component cost.

Summary of the invention

In order to overcome the above technical deficiencies, an object of the present invention is to provide an antenna for a mobile terminal and a mobile terminal having the same, which can reduce signal loss by arranging a ground matching unit between the grounding end of the switch and the radiator. Technical effect.

In a first aspect of the present application, an antenna for a mobile terminal is disclosed, including a radiator, a feed end, and a connection a feeding circuit of the radiator and the feeding end, the antenna further comprising: a switching switch comprising a fixed end connected to the radiator, a ground end and at least two free ends, wherein the switching switch switches the fixed end Connected to any free end; at least one matching unit, the first end of each matching unit is connected to a free end, and the second ends of all matching units are connected to the feeding circuit after being connected; the ground matching unit, Connected between the radiator and the ground.

Preferably, the switch is a single-pole double-throw switch, including a first free end and a second free end; the matching unit is one, connected in series between the first free end and the feeding circuit; The second free end is coupled to the feed circuit.

Preferably, the matching unit is a 0 ohm resistor.

Preferably, the ground matching unit is a first inductor, and the inductance of the first inductor is 4 nanohenries to 6 nanohenries.

Preferably, the feeding circuit includes: a first capacitor, a first end of the first capacitor is connected to the feeding end; a second inductor, a first end of the second inductor and the first capacitor The second end is connected, the second end of the second inductor is grounded; the third inductor, the first end of the third inductor is connected to the second end of the first capacitor; the second capacitor, the second The first end of the capacitor is connected to the second end of the third inductor, the second end of the second capacitor is grounded, and the matching unit is connected to the first end of the second capacitor.

Preferably, the capacitance of the first capacitor is 6 picofarads to 8 picofarads; the inductance of the second inductor is 10 nanohenries to 20 nanohenries; and the inductance of the third inductors is 1 nanohenry to 3 Naheng; the capacitance of the second capacitor is 1 picofarad to 3 picofarads.

Preferably, the antenna is a slot type antenna, the radiator is disposed on a slot side, and the switch, the feeding circuit, the matching unit, and the feeding end are disposed on the other side of the slot; the slot width It is from 1 mm to 3 mm.

Preferably, when the fixed end is connected to the first free end, the antenna operates at 790 MHz to 2170 MHz; when the fixed end is connected to the second free end, the antenna operates at 2300 MHz to 2700 MHz .

Preferably, the switch is embedded with control logic, and the preset free end is connected to the fixed end according to the frequency band of the wireless signal received by the radiator.

In a second aspect of the present application, a mobile terminal is disclosed, including the antenna described above.

After adopting the above technical solution, compared with the prior art, the following beneficial effects are obtained:

1. Reduce the loss of the received signal and improve the performance of the antenna;

2. placing components common in the feeding circuit at the front end of the switch, saving component costs;

3. It can optimize the performance of a single frequency band and improve the performance of the sky.

DRAWINGS

1 is a schematic structural diagram of an antenna for a mobile terminal in accordance with a preferred embodiment of the present invention;

2 is a schematic structural diagram of an antenna for a mobile terminal according to another preferred embodiment of the present invention;

3 is a schematic structural view of a feeding circuit in accordance with a preferred embodiment of the present invention;

4 is an experimental effect diagram of an antenna for a mobile terminal in accordance with a preferred embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an antenna for a mobile terminal in the prior art; FIG.

FIG. 6 is an experimental effect diagram of an antenna for a mobile terminal in the prior art.

Reference mark:

1-radiator, 2-feeder, 3-switch, 31-fixed, 32-free, 33-ground, 34-first free, 35-second free, 4-feed circuit , 5-matching unit, 6-ground matching unit, 7-first capacitor, 8-second inductor, 9-third inductor, 10-second capacitor.

Detailed ways

Advantages of the present invention are further explained below in conjunction with the accompanying drawings and specific embodiments.

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. The following description refers to the same or similar elements in the different figures unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with aspects of the present disclosure as detailed in the appended claims.

The terms used in the present disclosure are for the purpose of describing particular embodiments only, and are not intended to limit the disclosure. The singular forms "a", "the" and "the" It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, the first information may also be referred to as second information without departing from the scope of the present disclosure. Similarly, the second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "when" or "in response to a determination."

In the description of the present invention, it is to be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", The orientation or positional relationship of the indications of "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the present invention and simplifying the description, rather than Indicating or dark The device or component referred to as having a particular orientation, constructed and operated in a particular orientation is not to be construed as limiting the invention.

In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "mounted", "connected", and "connected" are to be understood broadly, and may be, for example, mechanical or electrical, or both. The internal communication of the components may be directly connected or indirectly connected through an intermediate medium. For those skilled in the art, the specific meanings of the above terms may be understood according to specific circumstances.

In the following description, the use of suffixes such as "module", "component" or "unit" for indicating an element is merely an explanation for facilitating the present invention, and does not have a specific meaning per se. Therefore, "module" and "component" can be used in combination.

1 is a schematic structural diagram of an antenna for a mobile terminal according to a preferred embodiment of the present invention, where the antenna includes:

- radiator 1

The radiator 1 is used to transmit or receive a radio signal, and the antenna is supported to operate on a plurality of frequency bands. The radiator 1 is an antenna in a narrow sense, which is a transducer that converts a signal propagating on a wired medium into an electromagnetic wave propagating in an unbounded medium (usually free space), or vice versa; A component used in a radio device to transmit or receive electromagnetic waves. Radio communication, broadcasting, television, radar, navigation, electronic countermeasures, remote sensing, radio astronomy and other engineering systems, all using electromagnetic waves to transmit information, rely on antennas to work. Generally, the antennas are reversible, that is, the same antenna can be used as both a transmitting antenna and a receiving antenna; the same characteristic parameters of the same antenna as transmitting or receiving are the same; that is, the reciprocity theorem of the antenna. In this embodiment, the antenna has a richer content than a narrow antenna, and further includes a feeding circuit and a feeding end 2 that cooperate with the radiator 1 . The antenna works in a frequency band of a mobile communication network, and includes multiple network standards such as 2G, 3G, and 4G, and supports the mobile terminal to perform information interaction with the outside. Depending on the operating frequency band and the application, the radiator 1 is designed in a different configuration. For example, the radiator 1 in the mobile terminal must be designed according to the structural characteristics of the mobile terminal, for example, using a mobile terminal. The metal casing and the gap on the casing realize electromagnetic vibration to realize miniaturization of the radiator 1. For example, the radiator 1 is also used for laboratory testing of the antenna, which must be designed according to the laboratory environment, can cover various frequency bands required for the experiment, and has less restrictions on the size.

-feed terminal 2

The feeding end 2 is a signal input end or an output end of the antenna. When the antenna transmits a signal, the feeding end 2 receives an electrical signal sent by a signal source and passes through the feeding circuit 4 and the radiation. The body 1 forms a radio signal for transmitting; when the antenna receives the signal, the wireless signal received by the radiator 1 is converted into an electrical signal by the feeding circuit 4, and then transmitted by the feeding end 2 to other components. deal with. The feed end 2 is often associated with a radio frequency chip or base With a chip connection, the received RF signal is processed to convert the RF signal into a digital signal.

-feed circuit 4

The feed circuit 4 is composed of components such as a resistor, a capacitor, an inductor, etc., and can be oscillated with the radiator 1 and transmitted as electromagnetic waves through the radiator 1 , or can be received by the radiator 1 . The wireless signal is converted into an electrical signal. The role of the feed circuit 4 in the antenna is critical. Without the feed circuit 4, the antenna cannot oscillate and cannot transmit or receive electromagnetic wave signals. The structure and electrical parameters of the feed circuit 4 will affect the working frequency band and affect the performance of the antenna. Therefore, the performance of the antenna can be optimally adjusted by changing the parameters of the components of the feed circuit. The feed circuit often employs an L-type circuit, a π-type circuit, a combination of an L-type circuit and a π-type circuit, a combination of two L-type circuits, or a combination of two π-type circuits.

-Switch 3

The changeover switch 3 includes a fixed end 31 connected to the radiator 1 , a ground end 33 , and at least two free ends 32 . The changeover switch 3 switches the fixed end 31 to be connected to any free end 32 . The switch 3 can control the fixed end 31 to be connected to one of the free ends 32 to realize the communication between the two sides of the circuit, and the unconnected free end 32 is in a floating state. The changeover switch 3 may be a single-pole double-throw switch, a single-pole three-throw switch, or the like having a switching function. The switch 3 also has a grounding end 33 connectable to ground to ground the switch 3 to provide a ground reference point. The fixed end 31 is directly connected to the radiator 1 .

- matching unit 5

The matching unit 5 is at least one, the first end of each matching unit 5 is connected to a free end 32, and the second ends of all matching units 5 are connected in parallel to the feeding circuit 4. Each matching unit 5 can use different types of components or select the same components with different parameters. The changeover switch 3 selects a different free end 32 to be connected to the fixed end 31, that is, a different matching unit 5 is selected to be connected to the fixed end. The matching unit 5 can select components suitable for matching different frequency bands, and form a signal path together with the feeding circuit 4, so that the switching switch 3 can select and adapt to signal paths of different frequency bands to achieve optimal frequency in different frequency bands. Antenna performance.

- Ground matching unit 5

The ground matching unit 5 is connected in series between the radiator 1 and the ground terminal 33. The grounding matching unit 5 is an important technical feature that is different from the prior art. In the prior art, the grounding end 33 is directly connected to the radiator 1 (see FIG. 5), and provides grounding impedance for the switching switch 3 and the antenna. . In the present invention, the ground matching unit 5 is connected in series between the radiator 1 and the grounding end 33, and the grounding matching unit is connected to the grounding unit before the signal generated by the radiator 1 enters the switching switch 3. 5 matching, reducing signal loss.

Referring to FIG. 2, which is a schematic structural diagram of an antenna for a mobile terminal according to another preferred embodiment of the present invention, The changeover switch 3 is a single pole double throw switch including a first free end 34 and a second free end 35. In the embodiment, the free end 32 of the changeover switch 3 is two, and the changeover switch 3 is a single-pole double-throw switch. The common models are RF1119ATR7 or ADRF5024. The matching unit 5 is one connected in series between the first free end 34 and the feeding circuit 4; the second free end 35 is connected to the feeding circuit 4. In this embodiment, there is only one matching unit 5, and the first free end 34 is connected to the feeding circuit 4, and the second free end 35 has no corresponding matching unit 5. In the embodiment, the switch 3 can select the first free end 34 or the second free end 35 to form different signal paths, and implement two frequency band matching modes.

As a further improvement of the above antenna, the matching unit 5 is a 0 ohm resistor. Although the resistance of 0 ohm is approximately 0 ohm, it still plays a role of signal matching in the field of antennas, and there is still a performance difference compared with the way in which the wires are directly connected. In addition, in the circuit board design, the replacement of components is often considered. Each matching unit 5 has a corresponding solder joint. The use of a 0 ohm resistor is also an optional connection method, and it is not necessary to re-create a new circuit board. cut costs.

As a further improvement of the above antenna, the ground matching unit 6 is a first inductance, and the inductance of the first inductance is 4 nanohenries to 6 nanohenries. The improved embodiment further preferably has the ground matching unit 6 as a first inductor whose inductance value is preferably 5.1 nanohenry. The Nahan is nH.

As a further improvement of the antenna, when the fixed end 31 is connected to the first free end 34, the antenna operates at 790 MHz to 2170 MHz; when the fixed end 31 is connected to the second free end 34 The antenna operates from 2300 MHz to 2700 MHz. The improved embodiment further clarifies the optimal operating frequency range of the antenna when the switch 3 is switched to different free ends on the basis of FIG. 2 .

In this embodiment, the matching component of the matching unit 5 or the feeding circuit 4 in the prior art is disposed between the radiator 1 and the switching switch 3, so that the received signal passes by. The switch 3 is matched before the switch 3 is reduced, reducing signal loss.

Referring to FIG. 3, which is a schematic structural diagram of a feeding circuit 4 according to a preferred embodiment of the present invention, the feeding circuit 4 includes:

- first capacitor 7

The first end of the first capacitor 7 is connected to the feed end 2, and the capacitance of the first capacitor 7 is 6 picofarads to 8 picofarads, and the skin method is pF.

- second inductance 8

The first end of the second inductor 8 is connected to the second end of the first capacitor 7, and the second end of the second inductor 8 is grounded. The inductance of the second inductor 8 is 10 nanohenry to 20 nanohenry.

- third inductance 9

The first end of the third inductor 9 is connected to the second end of the first capacitor 7. The inductance of the third inductor 9 is 1 nanohenry to 3 nanohenry.

- second capacitor 10

The first end of the second capacitor 10 is connected to the second end of the third inductor 9, and the second end of the second capacitor 10 is grounded. The capacitance of the second capacitor 10 is from 1 picofarad to 3 picofarads.

The matching unit 5 is connected to the first end of the second capacitor 10. That is to say, the second ends of all the matching units 5 are connected to one point and then connected to the first end of the second capacitor 10, which is also the connection point of the matching unit 5 and the feeding circuit 4. The connection point of the feeding circuit 4 and the feeding end 2 is at the first end of the first capacitor 7.

As a further improvement of the antenna, the antenna is a U-shaped antenna. The U-shaped antenna strip is a design of the back of the fuselage commonly used by the mobile terminal, and the antenna strip is named after a curved shape similar to the letter "U". The mobile terminal to which the U-shaped antenna is applied is generally designed as a metal casing, and the U-shaped antenna is disposed at the top or bottom of the mobile terminal, and may also adopt a dual antenna design, and is provided at the top and bottom of the mobile terminal. U-shaped antenna.

As a further improvement of the antenna, the antenna is any one of a slit type, a unipolar type, or an inverted F type. The preferred embodiment is preferred for the type of antenna. A slot antenna is a common antenna for a mobile terminal, and a gap needs to be formed on the mobile terminal. The slot itself is insulated, and the two sides of the slot are metal regions, and the feeding circuit is bridged. On the slit, a radiator 1 is disposed on one side of the slit, and a feeding end 2 is disposed on the other side. The monopole antenna, that is, the radiator 1 of the antenna has a unipolar extension, and has no physical structure extending left and right, and the working frequency band of the monopole antenna is relatively concentrated. The radiating body 1 of the inverted F-type antenna is generally in a lying F shape, wherein two laterally extending ends of the "F" are respectively connected to the feeding circuit, and the inverted F-type antenna can be adapted to a plurality of frequency ranges, if matched with the switch 3 , can switch a variety of frequency bands.

As a further improvement of the antenna, the antenna is a slot type antenna, the radiator 1 is disposed on a slot side, and the switch 3, the feeding circuit 4, the matching unit 5, and the feeding end 2 are disposed at the slot The other side of the slit; the slit has a width of from 1 mm to 3 mm, preferably 2 mm. A slot type antenna is increasingly applied to the mobile terminal, in particular, a mobile terminal having a metal casing, the gap being an insulator, and the metal casing is divided into two independent parts as induction of the antenna Part of the work with the radiator. The radiator 1 is connected to the circuit on the other side of the slit by one or more positions. The position of each component in the antenna also affects the performance of the antenna. In the embodiment, the switch 3 is spaced apart from the feed end 2 by 26 mm.

As a further improvement of the antenna, the changeover switch 3 is a single-pole multi-throw switch of a microelectromechanical process. Microcomputer Electrical technology is a hot spot in the development of manufacturing technology in recent years. The equipment or components manufactured are also called MEMS, MEMS for short, and Micro-Electro-Mechanical System. The microelectromechanical system is also called microelectromechanical system, microsystem, micromachined, etc., and refers to a high-tech device with a size of a few millimeters or even smaller. The internal structure of the microelectromechanical system is generally on the order of micrometers or even nanometers, and is an independent smart system. Microelectromechanical systems are developed on the basis of microelectronics technology (semiconductor manufacturing technology), combining high-tech electronic machinery made by lithography, etching, thin film, LIGA, silicon micromachining, non-silicon micromachining and precision machining. Device. Since the available space resources in the mobile terminal are tight, the components produced by the microelectromechanical process have the advantage of being small in size, and the switch 3 is also referred to as a MEMS switch. The concept of MEMS switches was introduced in the late 1980s and early 1990s and is of great appeal to RF engineers. Their potential includes reducing the total area of chips, power consumption and device cost. Common MEMS switches are single-pole four-throw (SP4T) MEMS switches of the ADGM1304. They also feature electrostatic protection. Compared to RF relays, MEMS switches are up to 95% smaller, 10 times more reliable, and 30 times faster. The power consumption is reduced by 10 times. The switch 3 is a single-pole multi-throw switch, wherein the single-pole is connected to the fixed end 31, and different free ends 32 can be selected for the throwing connection, and finally a one-to-many selection mode can be realized, according to the feeding circuit. The number of switches 3 has a number of corresponding free ends 32.

As a further improvement of the antenna, the switch 3 embeds control logic, and the preset free end 32 is connected to the fixed end 31 according to the radio signal band received by the radiator 1 . The switch 3 is a programmable logic control device and has the capability of identifying the frequency band of the signal received by the fixed terminal 31. When the switch 3 is used, the control logic can be written in the switch 3 in advance, and the free end 32 corresponding to the different matching unit 5 is connected to the fixed end 31 according to the received signal band. The selection of the feeding circuit corresponding to different frequency bands achieves optimal matching of the antenna performance in the frequency band.

As a further improvement of the antenna, between the feeding circuit 4 and the switching switch 3, the feeding circuit 4 and the feeding end 2 are respectively connected by an impedance cable with a resistance value of 50 ohms. . The improvement further defines the connection manner between the components in the antenna. In the antenna, the impedance of the signal line plays a vital role in signal transmission and anti-interference. In this embodiment, a 50 ohm impedance line is selected. The cable is connected to the feed circuit 4 and the changeover switch 3, and the feed circuit 4 and the feed terminal 2 are connected, which can reduce signal crosstalk on the transmission line and reduce the distortion of the signal.

Referring to FIG. 4, an experimental effect diagram of an antenna for a mobile terminal in accordance with a preferred embodiment of the present invention is obtained based on the antenna described in FIG. 2. When the working frequency band of the antenna is 790 MHz to 2170 MHz, the switch 3 selects the first free end 34 to be connected; when the working frequency band of the antenna is The switch 3 selects the second free end 35 to be connected at 2300 MHz to 2700 MHz. The abscissa of the experimental effect diagram is a frequency band, and the unit is MHz, that is, megahertz; the ordinate of the experimental effect diagram is a signal gain, and the unit is dB, that is, decibel.

Referring to FIG. 5 , which is a schematic structural diagram of an antenna for a mobile terminal in the prior art, the grounding matching unit 6 is not disposed in the antenna of the prior art, and the radiator 1 is directly connected to the grounding end 33 . The first free end 34 is connected to the feed circuit 4 via the matching unit 5, and the matching unit 5 is an inductance of 5.1 nanohenry. The second free end 35 is directly connected to the feed circuit 4. The difference between the prior art and FIG. 2 in the present invention is that the 5.1 nanohenry inductance of the matching unit 5 in the prior art is moved between the radiator 1 and the grounding end 33, and the matching unit is originally The position of 5 is replaced by a 0 ohm resistor.

Referring to FIG. 6 , which is an experimental effect diagram of an antenna for a mobile terminal in the prior art, the experimental effect diagram is obtained based on the experiment of FIG. 5 . When the antenna operating frequency band is 790 MHz to 2170 MHz, the switch 3 selects the first free end 34 to be connected; when the antenna operating frequency band is 2300 MHz to 2700 MHz, the switch 3 selects the second free Terminal 35 is connected.

Comparing the experimental results in FIG. 4 and FIG. 6, it can be seen that in FIG. 4, that is, the efficiency of the antenna in the present invention is higher than that in the prior art, especially in the frequency range of 2110 MHz to 2170 MHz, that is, in the range of 2100 MHz of WCDMA. The antenna of the present invention has less loss and higher efficiency.

In a second aspect of the present application, a mobile terminal is disclosed, including the antenna described above. The mobile terminal includes a radio frequency chip, and the radio frequency chip is responsible for radio frequency transceiver, frequency synthesis, and power amplification. The radio frequency chip is simply a receiving signal and a transmitting signal, and is a component that communicates with the base station when the mobile terminal picks up a call and receives a short message. The radio frequency chip has a radio frequency signal interface and is connected to the feeding end 2 . With the development of integrated circuit technology, many manufacturers integrate the radio frequency chip into the communication baseband chip, and integrate the signal transmission and processing and processing.

The mobile terminal can be implemented in various forms. For example, the terminal described in the present invention may include a mobile terminal such as a mobile phone, a smart phone, a notebook computer, a PDA (Personal Digital Assistant), a PAD (Tablet), a PMP (Portable Multimedia Player), a navigation device, and the like, and such as Fixed terminal for digital TV, desktop computer, etc. In the following, it is assumed that the terminal is a mobile terminal. However, those skilled in the art will appreciate that configurations in accordance with embodiments of the present invention can be applied to fixed type terminals in addition to components that are specifically for mobile purposes.

It should be noted that the embodiments of the present invention are preferred embodiments, and are not intended to limit the scope of the present invention. Any one skilled in the art may use the above-disclosed technical contents to change or modify the equivalent embodiments. Any modification or equivalent changes and modifications of the above embodiments in accordance with the technical spirit of the present invention are still within the scope of the technical solutions of the present invention.

Claims

An antenna for a mobile terminal, comprising: a radiator, a feeding end, and a feeding circuit connecting the radiator and the feeding end, wherein the antenna further comprises:

The switch includes a fixed end connected to the radiator, a ground end, and at least two free ends, and the switch switch switches the fixed end to be connected to any free end;

At least one matching unit, the first end of each matching unit is connected to a free end, and the second ends of all matching units are connected to the feeding circuit after being connected;

The ground matching unit is connected in series between the radiator and the ground.
The antenna of claim 1 wherein:

The switch is a single pole double throw switch, including a first free end and a second free end;

The matching unit is one, connected in series between the first free end and the feeding circuit;

The second free end is coupled to the feed circuit.
The antenna according to claim 2, wherein

The matching unit is a 0 ohm resistor.
The antenna according to any one of claims 1 to 3, wherein

The ground matching unit is a first inductor, and the first inductor has an inductance value of 4 nanohenries to 6 nanohenries.
The antenna according to any one of claims 1 to 3, wherein

The feed circuit includes:

a first capacitor, the first end of the first capacitor is connected to the feed end;

a second inductor, a first end of the second inductor is connected to a second end of the first capacitor, and a second end of the second inductor is grounded;

a third inductor, the first end of the third inductor being connected to the second end of the first capacitor;

a second capacitor, a first end of the second capacitor is connected to a second end of the third inductor, and a second end of the second capacitor is grounded;

The matching unit is connected to the first end of the second capacitor.
The antenna according to claim 5, wherein

The capacitance of the first capacitor is 6 picofarads to 8 picofarads;

The inductance of the second inductor is 10 nanohenry to 20 nanohenry;

The inductance of the third inductor is 1 nanohenry to 3 nanohenry;

The capacitance of the second capacitor is from 1 picofarad to 3 picofarads.
The antenna according to any one of claims 1 to 3, wherein

The antenna is a slot type antenna, the radiator is disposed on a slot side, and the switch, the feeding circuit, the matching unit, and the feeding end are disposed on the other side of the slot;

The slit has a width of from 1 mm to 3 mm.
The antenna according to claim 2 or 3, wherein

When the fixed end is connected to the first free end, the antenna operates at 790 MHz to 2170 MHz;

When the fixed end is connected to the second free end, the antenna operates at 2300 MHz to 2700 MHz.
The antenna according to any one of claims 1 to 3, wherein

The switch is embedded with control logic, and the preset free end is connected to the fixed end according to the frequency band of the wireless signal received by the radiator.
A mobile terminal characterized by comprising the antenna of claim 1.