KR101952173B1 - Mobile terminal - Google Patents

Abstract

A mobile terminal according to an embodiment of the present invention includes a first member and a second member that are plate-shaped and face each other with an isolating member having a certain permittivity or more interposed therebetween, a first antenna element that is grounded to the first member, By including the second antenna element spaced from the first antenna element and grounded to the second member, the antenna can be more efficiently implemented in a small space and the performance of the antenna can be maintained, thereby making the mobile terminal more compact .

Description

[0001] MOBILE TERMINAL [0002]

One embodiment of the present invention relates to a mobile terminal having an antenna device for transmitting and receiving radio signals.

Mobile communication services continue to evolve with the development of mobile communication technology and the demand of consumers who want more diverse services. Early mobile communication has been focused on simple voice communication. In recent years, however, various mobile communication services such as multimedia services such as music and movies, wireless portable Internet services capable of using the Internet at high speed on the move, and satellite communication services providing mobile communication across borders have appeared.

Meanwhile, in a general mobile communication terminal, the radiation efficiency of the antenna is lowered, the frequency band is narrowed, and the antenna gain is reduced while miniaturizing the antenna of the mobile communication terminal. However, in spite of this performance deterioration, mobile communication terminals are continuously required to be miniaturized, multifunctional, and high performance. Therefore, the antenna used in the mobile communication system is required to be miniaturized and high in performance.

In addition, since the terminal design is important and the size and weight of the antenna are reduced, the performance of the built-in antenna degrades compared to the long antenna. In order to improve the performance and smooth data communication, the mobile terminal has a main antenna for transmitting / And a separate diversity antenna is provided to prevent interference.

Such a diversity antenna has a planar inverted-F antenna (PIFA), a meander antenna having a bent pattern, a loop antenna Loop Antenna, Inverted F-Antenna, and Wire Type Antenna have been developed as antennas that are easy to mount even in a narrow space inside the terminal body.

However, when the conventional external antenna is used, there is no phenomenon of deterioration of the antenna performance due to a sufficient distance from the diversity antenna. However, when the built-in main antenna occupying a certain area or more is located in the internal space of the terminal, The isolation is less than 5 dB and the main antenna performance is degraded due to mutual interference.

In addition to the conventional single frequency transmission / reception function, a dual mode or triple mode terminal has been introduced as a communication technology applicable to a mobile terminal has been developed. CDMA, PCS, WCDMA, GSM, GPS, WIFI, A variety of applications such as Bluetooth, Long Term Evolution (LTE) and Winmax functions are implemented in one terminal and the terminal size is miniaturized so that many antennas are located in a narrow space.

In addition, in a terminal to which diversity antennas of applications having different frequency bands are applied, it is difficult to secure a mounting space and a separation distance of diversity antennas, and problems due to antenna mutual interference are further exacerbated.

Accordingly, a mounting space and a separation distance can be ensured, and an antenna device having higher efficiency can be considered.

It is an object of the present invention to provide a mobile terminal having an improved antenna device.

It is another object of the present invention to provide an antenna device having a good radio performance in a smaller space and a mobile terminal having the antenna device.

According to an aspect of the present invention, there is provided a mobile terminal comprising: a plate-like first member and a second member facing each other with an isolating member having a constant dielectric constant greater than a predetermined value; And a second antenna element spaced apart from the first antenna element and grounded to the second member.

According to an example of the present invention, the first and second members may be formed as a part of a frame to which a display module and a printed circuit board embedded in a terminal are coupled.

According to an example of the present invention, a printed circuit board is coupled to one surface of the first member, and a display module is coupled to one surface of the second member.

According to an embodiment of the present invention, at least a part of the frame may be exposed to the outside to form an appearance of the terminal.

According to an example of the present invention, the first antenna element may be disposed at one end of the terminal body, and the second antenna element may be disposed at the other end of the terminal body.

According to an example of the present invention, the first and second antenna elements may be configured to operate as multiple input multiple output (MIMO).

According to an example of the present invention, an antenna gain difference between the first antenna element and the second antenna element may be 3 dB to 6 dB.

According to an example of the present invention, an antenna to antenna isolation between the first antenna element and the second antenna element may be formed to be at least 8 dB.

According to an example of the present invention, an envelope correlation coefficient (ECC) between the first antenna element and the second antenna element may be within 0.5.

According to another aspect of the present invention, there is provided a mobile communication terminal including a terminal body having a frame formed to support the inside thereof, a first antenna element and a second antenna element spaced apart from each other at both sides of the frame, Wherein the frame includes a first conductive member to which the first antenna element is grounded, a second conductive member to which the second antenna element is grounded, and a second conductive member that spatially separates the first antenna element and the second antenna element. And a separator formed between the first conductive member and the second conductive member to separate the first conductive member and the second conductive member.

The mobile terminal according to at least one embodiment of the present invention configured as described above can realize a more efficient antenna in a small space and can maintain the performance of the antenna, thereby making the mobile terminal more compact.

Further, by providing a plurality of grounds and forming the grounds so as to be spatially separated from each other, the degree of isolation between the first antenna and the second antenna can be improved, and even if the distance between the first antenna element and the second antenna element is within a certain distance, The MIMO ECC is within a certain level and can exhibit satisfactory performance.

1 is a block diagram of a mobile terminal according to an embodiment of the present invention;
2A is a front perspective view of a mobile terminal according to the present invention;
Figure 2b is a rear perspective view of the mobile terminal of Figure 2a.
3 is an exploded view of the mobile terminal of FIG.
4 is a diagram showing a configuration of a general multi-antenna system;
FIG. 5 illustrates a Multiple Input Multiple Output (MIMO) communication system. FIG.
6 is a conceptual diagram showing an example of mounting a frame and an antenna mounted on a main body according to embodiments of the present invention;
7 is a conceptual diagram illustrating a connection relationship between a frame and an antenna according to an embodiment of the present invention;

Hereinafter, a mobile terminal related to the present invention will be described in detail with reference to the drawings. In the present specification, the same or similar reference numerals are given to different embodiments in the same or similar configurations. As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

The mobile terminal described in this specification may include a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a PDA (Personal Digital Assistants), a PMP (Portable Multimedia Player), navigation and the like. However, it will be understood by those skilled in the art that the configuration according to the embodiments described herein may be applied to a fixed terminal such as a digital TV, a desktop computer, and the like, unless the configuration is applicable only to a mobile terminal.

The mobile terminal 100 includes a wireless communication unit 110, an audio / video input unit 120, a user input unit 130, a sensing unit 140, an output unit 150, a memory 160, A controller 170, a controller 180, a power supply 190, and the like. The components shown in FIG. 1 are not essential, and a mobile terminal having more or fewer components may be implemented. Hereinafter, the components will be described in order.

The wireless communication unit 110 may include one or more modules for enabling wireless communication between the mobile terminal 100 and the wireless communication system or between the mobile terminal 100 and the network in which the mobile terminal 100 is located. For example, the wireless communication unit 110 may include a broadcast receiving module 111, a mobile communication module 112, a wireless Internet module 113, a short range communication module 114, and a location information module 115 .

The broadcast receiving module 111 receives broadcast signals and / or broadcast-related information from an external broadcast management server through a broadcast channel.

The broadcast channel may include a satellite channel and a terrestrial channel. The broadcast management server may refer to a server for generating and transmitting broadcast signals and / or broadcast related information, or a server for receiving broadcast signals and / or broadcast related information generated by the broadcast management server and transmitting the generated broadcast signals and / or broadcast related information. The broadcast signal may include a TV broadcast signal, a radio broadcast signal, a data broadcast signal, and a broadcast signal in which a data broadcast signal is combined with a TV broadcast signal or a radio broadcast signal.

The broadcast-related information may refer to a broadcast channel, a broadcast program, or information related to a broadcast service provider. The broadcast-related information may also be provided through a mobile communication network. In this case, it may be received by the mobile communication module 112.

The broadcast-related information may exist in various forms. For example, an EPG (Electronic Program Guide) of DMB (Digital Multimedia Broadcasting) or an ESG (Electronic Service Guide) of Digital Video Broadcast-Handheld (DVB-H).

For example, the broadcast receiving module 111 may be a Digital Multimedia Broadcasting-Terrestrial (DMB-T), a Digital Multimedia Broadcasting-Satellite (DMB-S), a Media Forward Link Only Broadcast-Handheld (ISDB-T), Integrated Services Digital Broadcast-Terrestrial (ISDB-T), and the like. Of course, the broadcast receiving module 111 may be adapted to other broadcasting systems as well as the digital broadcasting system described above.

The broadcast signal and / or broadcast related information received through the broadcast receiving module 111 may be stored in the memory 160.

The mobile communication module 112 transmits and receives radio signals to at least one of a base station, an external terminal, and a server on a mobile communication network. The wireless signal may include various types of data depending on a voice call signal, a video call signal or a text / multimedia message transmission / reception.

The wireless Internet module 113 is a module for wireless Internet access, and may be built in or externally attached to the mobile terminal 100. WLAN (Wi-Fi), Wibro (Wireless broadband), Wimax (World Interoperability for Microwave Access), HSDPA (High Speed Downlink Packet Access) and the like can be used as wireless Internet technologies.

The short-range communication module 114 refers to a module for short-range communication. Bluetooth, Radio Frequency Identification (RFID), infrared data association (IrDA), Ultra Wideband (UWB), ZigBee, and the like can be used as a short range communication technology.

The position information module 115 is a module for obtaining the position of the mobile terminal, and a representative example thereof is a Global Position System (GPS) module.

Referring to FIG. 1, an A / V (Audio / Video) input unit 120 is for inputting an audio signal or a video signal, and may include a camera 121 and a microphone 122. The camera 121 processes image frames such as still images or moving images obtained by the image sensor in the video communication mode or the photographing mode. The processed image frame can be displayed on the display unit 151. [

The image frame processed by the camera 121 may be stored in the memory 160 or transmitted to the outside through the wireless communication unit 110. [ Two or more cameras 121 may be provided depending on the use environment.

The microphone 122 receives an external sound signal through a microphone in a communication mode, a recording mode, a voice recognition mode, or the like, and processes it as electrical voice data. The processed voice data can be converted into a form that can be transmitted to the mobile communication base station through the mobile communication module 112 when the voice data is in the call mode, and output. Various noise reduction algorithms may be implemented in the microphone 122 to remove noise generated in receiving an external sound signal.

The user input unit 130 generates input data for a user to control the operation of the terminal. The user input unit 130 may include a key pad dome switch, a touch pad (static / static), a jog wheel, a jog switch, and the like.

The sensing unit 140 senses the current state of the mobile terminal 100 such as the open / close state of the mobile terminal 100, the position of the mobile terminal 100, the presence or absence of user contact, the orientation of the mobile terminal, And generates a sensing signal for controlling the operation of the mobile terminal 100. For example, when the mobile terminal 100 is in the form of a slide phone, it is possible to sense whether the slide phone is opened or closed. It is also possible to sense whether the power supply unit 190 is powered on, whether the interface unit 170 is connected to an external device, and the like. Meanwhile, the sensing unit 140 may include a proximity sensor 141.

The output unit 150 is for generating output related to the visual, auditory or tactile sense and includes a display unit 151, an audio output module 152, an alarm unit 153, and a haptic module 154 .

The display unit 151 displays (outputs) information processed by the mobile terminal 100. For example, when the mobile terminal is in the call mode, a UI (User Interface) or a GUI (Graphic User Interface) associated with a call is displayed. When the mobile terminal 100 is in the video communication mode or the photographing mode, the photographed and / or received video or UI and GUI are displayed.

The display unit 151 may be a liquid crystal display (LCD), a thin film transistor-liquid crystal display (TFT LCD), an organic light-emitting diode (OLED), a flexible display display, and a 3D display.

Some of these displays may be transparent or light transmissive so that they can be seen through. This can be referred to as a transparent display, and a typical example of the transparent display is TOLED (Transparent OLED) and the like. The rear structure of the display unit 151 may also be of a light transmission type. With this structure, the user can see an object located behind the terminal body through the area occupied by the display unit 151 of the terminal body.

There may be two or more display units 151 according to the embodiment of the mobile terminal 100. For example, in the mobile terminal 100, a plurality of display portions may be spaced apart from one another or may be disposed integrally with each other, or may be disposed on different surfaces.

(Hereinafter, referred to as a 'touch screen') in which a display unit 151 and a sensor for sensing a touch operation (hereinafter, referred to as 'touch sensor') form a mutual layer structure, It can also be used as an input device. The touch sensor may have the form of, for example, a touch film, a touch sheet, a touch pad, or the like.

The touch sensor may be configured to convert a change in a pressure applied to a specific portion of the display unit 151 or a capacitance generated in a specific portion of the display unit 151 into an electrical input signal. The touch sensor can be configured to detect not only the position and area to be touched but also the pressure at the time of touch.

If there is a touch input to the touch sensor, the corresponding signal (s) is sent to the touch controller. The touch controller processes the signal (s) and transmits the corresponding data to the controller 180. Thus, the control unit 180 can know which area of the display unit 151 is touched or the like.

Referring to FIG. 1, a proximity sensor 141 may be disposed in an inner region of the mobile terminal or in the vicinity of the touch screen, which is surrounded by the touch screen. The proximity sensor refers to a sensor that detects the presence or absence of an object approaching a predetermined detection surface or a nearby object without mechanical contact using the force of an electromagnetic field or infrared rays. The proximity sensor has a longer life span than the contact sensor and its utilization is also high.

Examples of the proximity sensor include a transmission type photoelectric sensor, a direct reflection type photoelectric sensor, a mirror reflection type photoelectric sensor, a high frequency oscillation type proximity sensor, a capacitive proximity sensor, a magnetic proximity sensor, and an infrared proximity sensor. And to detect the proximity of the pointer by the change of the electric field along the proximity of the pointer when the touch screen is electrostatic. In this case, the touch screen (touch sensor) may be classified as a proximity sensor.

Hereinafter, for convenience of explanation, the act of recognizing that the pointer is positioned on the touch screen while the pointer is not in contact with the touch screen is referred to as "proximity touch & The act of actually touching the pointer on the screen is called "contact touch. &Quot; The position where the pointer is proximately touched on the touch screen means a position where the pointer is vertically corresponding to the touch screen when the pointer is touched.

The proximity sensor detects a proximity touch and a proximity touch pattern (e.g., a proximity touch distance, a proximity touch direction, a proximity touch speed, a proximity touch time, a proximity touch position, a proximity touch movement state, and the like). Information corresponding to the detected proximity touch operation and the proximity touch pattern may be output on the touch screen.

The audio output module 152 may output audio data received from the wireless communication unit 110 or stored in the memory 160 in a call signal reception mode, a call mode or a recording mode, a voice recognition mode, a broadcast reception mode, The sound output module 152 also outputs sound signals related to functions (e.g., call signal reception sound, message reception sound, etc.) performed in the mobile terminal 100. [ The audio output module 152 may include a receiver, a speaker, a buzzer, and the like.

The alarm unit 153 outputs a signal for notifying the occurrence of an event of the mobile terminal 100. Examples of events that occur in the mobile terminal include call signal reception, message reception, key signal input, touch input, and the like. The alarm unit 153 may output a signal for notifying the occurrence of an event in a form other than the video signal or the audio signal, for example, vibration. The video signal or the audio signal may be output through the display unit 151 or the audio output module 152 so that they may be classified as a part of the alarm unit 153.

The haptic module 154 generates various tactile effects that the user can feel. A typical example of the haptic effect generated by the haptic module 154 is vibration. The intensity and pattern of the vibration generated by the hit module 154 can be controlled. For example, different vibrations may be synthesized and output or sequentially output.

In addition to the vibration, the haptic module 154 may include a pin arrangement vertically moving with respect to the contact skin surface, a spraying force or suction force of the air through the injection port or the suction port, a touch on the skin surface, contact of an electrode, And various tactile effects such as an effect of reproducing a cold sensation using an endothermic or exothermic element can be generated.

The haptic module 154 can be implemented not only to transmit the tactile effect through the direct contact but also to allow the user to feel the tactile effect through the muscular sensation of the finger or arm. The haptic module 154 may include two or more haptic modules 154 according to the configuration of the portable terminal 100.

The memory 160 may store a program for the operation of the controller 180 and temporarily store input / output data (e.g., a phone book, a message, a still image, a moving picture, etc.). The memory 160 may store data on vibration and sound of various patterns outputted when a touch is input on the touch screen.

The memory 160 may be a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (for example, SD or XD memory), a RAM (Random Access Memory), SRAM (Static Random Access Memory), ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), PROM A disk, and / or an optical disk. The mobile terminal 100 may operate in association with a web storage that performs a storage function of the memory 160 on the Internet.

The interface unit 170 serves as a path for communication with all external devices connected to the mobile terminal 100. The interface unit 170 receives data from an external device or supplies power to each component in the mobile terminal 100 or transmits data to the external device. For example, a wired / wireless headset port, an external charger port, a wired / wireless data port, a memory card port, a port for connecting a device having an identification module, an audio I / O port, A video input / output (I / O) port, an earphone port, and the like may be included in the interface unit 170.

The identification module is a chip for storing various information for authenticating the use right of the mobile terminal 100 and includes a user identification module (UIM), a subscriber identity module (SIM), a general user authentication module A Universal Subscriber Identity Module (USIM), and the like. Devices with identification modules (hereinafter referred to as "identification devices") can be manufactured in a smart card format. Accordingly, the identification device can be connected to the terminal 100 through the port.

When the mobile terminal 100 is connected to an external cradle, the interface unit 170 may be a path through which power from the cradle is supplied to the mobile terminal 100, or various commands A signal may be a path through which the signal is transmitted to the mobile terminal. The various command signals or the power source input from the cradle may be operated as a signal for recognizing that the mobile terminal is correctly mounted on the cradle.

The controller 180 typically controls the overall operation of the mobile terminal. For example, voice communication, data communication, video communication, and the like. The control unit 180 may include a multimedia module 181 for multimedia playback. The multimedia module 181 may be implemented in the control unit 180 or may be implemented separately from the control unit 180. [

The controller 180 may perform a pattern recognition process for recognizing handwriting input or drawing input performed on the touch screen as characters and images, respectively.

The power supply unit 190 receives external power and internal power under the control of the controller 180 and supplies power necessary for operation of the respective components.

The various embodiments described herein may be embodied in a recording medium readable by a computer or similar device using, for example, software, hardware, or a combination thereof.

According to a hardware implementation, the embodiments described herein may be implemented as application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays May be implemented using at least one of a processor, controllers, micro-controllers, microprocessors, and other electronic units for performing other functions. In some cases, The embodiments described may be implemented by the control unit 180 itself.

According to a software implementation, embodiments such as the procedures and functions described herein may be implemented with separate software modules. Each of the software modules may perform one or more of the functions and operations described herein. Software code can be implemented in a software application written in a suitable programming language. The software code is stored in the memory 160 and can be executed by the control unit 180. [

The portable terminal according to the present invention may include at least two cameras to capture a stereoscopic image. Further, the portable terminal according to the present invention may include a display unit capable of displaying a stereoscopic image.

The stereoscopic image that can be implemented on the display unit 151 of the portable terminal according to the present invention may be a monoscopic image in which the same image is provided in both eyes and a different image in both eyes (Streo scopic).

The monoscopic method in which the same image is provided in both eyes has an advantage that it can be implemented as a general display unit. More specifically, the control unit 180 arranges a polyhedron generated through one or more points, lines, faces, or a combination thereof on an imaginary three-dimensional space, and displays the image viewed from a specific point on the display unit 151 . Therefore, the substantial part of such a stereoscopic image can be referred to as a planar image.

The way in which different images are provided in both eyes (streo scopic) is a method using the principle of feeling a three-dimensional feeling when a person looks at an object with the naked eye. That is, two eyes of a person can see different planar images when they see the same object by the distance between them. These different planar images are transmitted to the brain through the retina, and the brain fuses them to feel the depth and reality of the stereoscopic image. Therefore, though there is some difference in each person, the binocular disparity due to the distance between the two eyes becomes three-dimensional.

The present invention includes two cameras for capturing a left eye image and a right eye image, respectively, which are photographed using binocular disparity, respectively, to form a three-dimensional sensation.

FIG. 2 is a perspective view of a mobile terminal according to an embodiment of the present invention, and FIG. 3 is a rear perspective view of the mobile terminal shown in FIG. 2. Referring to FIG.

1, 2A and 2B, the mobile terminal 200 includes a bar-shaped terminal body. However, the present invention is not limited thereto, and can be applied to various structures such as a slide type, a folder type, and a swing type in which two or more bodies are coupled to be movable relative to each other. Further, the mobile terminal described herein may be any portable electronic device having a camera and flash, such as a mobile phone, a smart phone, a notebook computer, a digital broadcast terminal, a Personal Digital Assistants ), A PMO (Portable Multimedia Player), and the like.

The terminal body includes a case (which may be referred to as a casing, a housing, a cover, and the like) that forms an appearance. The case may be divided into a front case 201, a rear case 202 covering a surface opposite to the front case, and a battery cover 203 coupled with the rear case 202. Various electronic components are embedded in the space formed between the front case 201 and the rear case 202. The cases may be formed by injection molding a synthetic resin, or may be formed to have a metal material such as stainless steel (STS) or titanium (Ti) or the like.

The terminal body includes a display unit 210, a first sound output unit 211, an input operation unit 217, and a front camera unit 216.

The display unit 210 includes an LCD (Liquid Crystal Display) module, an OLED (Organic Light Emitting Diodes) module, and an e-paper for visually expressing information. The display unit 210 may include touch sensing means for inputting data by a touch method. Hereinafter, the display unit 210 including the touch sensing unit will be referred to as a 'touch screen'. If any one of the touches on the touch screen 210 is touched, the contents corresponding to the touched position are input. The content input by the touch method may be a letter or a number, an instruction in various modes, a menu item which can be designated, and the like. The touch sensing means is formed in a translucent manner so that the display portion can be seen, and a structure for enhancing the visibility of the touch screen in a bright place may be included. Referring to FIG. 2, the touch screen 210 occupies most of the front surface of the front case 201.

The first sound output unit 211 may be implemented as a receiver for delivering a call sound to a user's ear or a loud speaker for outputting various alarm sounds or multimedia playback sounds.

The input operation unit 217 is operated to receive a command for controlling the operation of the mobile terminal 200, and may include a plurality of operation units. The operating units may also be referred to as manipulating portions, and any manner may be employed provided that the user has a tactile sense and operates in a tactile manner.

For example, a dome switch or touch screen capable of receiving a command or information by a push or touch operation of a user, a touch pad, or a wheel, a jog type or a joystick for rotating a key .

The contents input by the input operation unit 217 can be variously set. For example, to enter start, end, scroll, and the like.

The front camera unit 216 processes an image frame such as a still image or a moving image obtained by the image sensor in the video communication mode or the photographing mode. The processed image frame can be displayed on the display unit 210. [

The image frame processed by the front camera 216 can be stored in the memory 160 or transmitted to the outside through the wireless communication unit 110. [ The front camera 216 may be provided in two or more depending on the use environment.

The rear case 202 is provided with a side key 214, an interface unit 215, and an acoustic input unit 213.

The side key 214 may be collectively referred to as an operation unit and is capable of receiving a command for controlling the operation of the mobile terminal 200. The side key 214 may be employed in any manner as long as the user is operating in a tactile manner with a tactile impression. The content input by the side key 214 can be variously set. For example, by the side key 214, a command such as control of the image input units 216 and 221, size adjustment of the sound output from the sound output unit 211, or switching to the touch recognition mode of the display unit 210, Input can be received.

The sound input unit 213 may be implemented, for example, in the form of a microphone to receive a user's voice, other sounds, and the like.

The interface unit 215 is a channel through which the mobile terminal 200 related to the present invention can exchange data with an external device. For example, the interface unit 215 may be a wired or wireless connection terminal for connecting to an earphone, a port for short-range communication (for example, an IrDA port, a Bluetooth port, a wireless LAN port A wireless LAN port) or the like, or power supply terminals for supplying power to the mobile terminal 200. The interface unit 215 may be implemented as a socket for receiving an external card such as a SIM (Subscriber Identification Module) or a UIM (User Identity Module) or a memory card for storing information.

A power supply unit 240 and a rear camera unit 221 are disposed on the rear surface of the terminal body.

The power supply unit 240 supplies power to the mobile terminal 200. The power supply unit 240 may be built in the terminal body or may be detachable from the outside of the terminal body.

A flash (not shown) and a mirror (not shown) may be disposed adjacent to the rear camera unit 221. The flash illuminates the subject toward the subject when the subject is photographed by the rear camera unit 221.

A mirror (not shown) may be disposed adjacent to the flash. The mirror allows the user to illuminate the user's own face or the like in the case where the user intends to photograph (self-photograph) himself / herself by using the rear camera unit 221. [

The rear camera unit 221 may have a photographing direction substantially opposite to that of the front camera unit 216 and may be a camera having different pixels from the front camera unit 216. [

For example, the front camera unit 216 has low pixels so that it is easy to capture a face of a user in the case of a video call or the like and transmit the face to the other party. The rear camera unit 221 photographs a general subject and immediately transmits It is preferable to have a high pixel. The front and rear camera units 216 and 221 may be installed in the terminal body so as to be rotatable or pop-upable.

FIG. 3 is an exploded view of the mobile terminal of FIG.

2A and FIG. 3, the mobile terminal includes a window 210a and a display module 210b, which are coupled to one surface of the front case 201 and constitute the display unit 210. FIG.

The main circuit board 205 is mounted on the display module 210b. The main circuit board 205 may be configured as an example of a controller 180 (see FIG. 1) for operating various functions of the mobile terminal 200. The main circuit board 205 is formed to process an input signal.

In other words. The main circuit board 205 is electrically connected to the sound output module 211, the display module 210b, the battery 240 and the front and rear camera units 216 and 221.

The battery 240 may be detachably attached to the terminal body.

The window 210a is coupled to one surface of the front case 201. [ A touch sensor (not shown) may be mounted on the window 210a. The touch sensor is formed to sense a touch input and is made of light transmissive. The touch sensor may be mounted on the front surface of the window 210a and may be configured to convert a change in voltage or the like occurring in a specific portion of the window 210a into an electrical input signal.

The display module 210b is mounted on the rear surface of the window 210a. In this embodiment, a thin film transistor-liquid crystal display (TFT LCD) is disclosed as an example of the display module 210a, but the present invention is not limited thereto. For example, the display module 210a may be a liquid crystal display (LCD), an organic light-emitting diode (OLED), a flexible display, a 3D display .

Hereinafter, the MIMO antenna technology related to the present invention will be described with reference to FIGS. 4 to 5. FIG.

MIMO is an abbreviation of "Multiple Input Multiple Output". It is a way to improve transmission / reception data efficiency by adopting multiple transmit antennas and multiple receive antennas by avoiding using one transmit antenna and one receive antenna so far It says. That is, the present invention is applied to a technique of collecting pieces of fragmentary data received from various antennas without relying on a single antenna path in order to receive one entire message.

Such a MIMO technique can improve the data transmission speed in a specific range or increase the system range for a specific data transmission speed. That is, the MIMO technology is a next-generation mobile communication technology widely used in user equipments (UEs) and repeaters of mobile communication. The above technology is attracting attention as a technology capable of overcoming the limitation of the transmission capacity of mobile communication due to the expansion of data communication and the like.

4 is a diagram showing a configuration of a general multi-antenna system.

As shown in FIG. 4, if the number of antennas is simultaneously increased at the transmitting / receiving end, the theoretical channel transmission capacity increases in proportion to the number of antennas, unlike the case where a plurality of antennas are used only at the transmitter and the receiver. .

5 is a diagram illustrating a multiple-input multiple-output (MIMO) communication system. As described above, the MIMO technique refers to a technique for performing communication using multiple transmit antennas and / or multiple receive antennas. The technology of multiple antennas is divided into a spatial diversity scheme for improving transmission reliability using symbols that have passed through various channel paths and a spatial diversity scheme for simultaneously transmitting a plurality of data symbols using a plurality of transmission antennas (spatial multiplexing) method. In addition, studies to appropriately combine the two methods and obtain the merits of the respective methods have been recently studied. Each method will be described in more detail as follows.

First, the space diversity scheme is divided into a space time block code sequence scheme, a space time trellis code scheme scheme using both diversity gain and coding gain, . In general, the bit error rate improvement performance and the code generation freedom are excellent in the trellis code scheme, but the computation complexity is simple in the space-time block code. The spatial diversity gain can be obtained by multiplying the number of transmitting antennas by the number of receiving antennas.

Second, the spatial multiplexing scheme transmits different data streams through each transmission antenna. At this time, since mutual interference occurs between the data transmitted simultaneously from the transmitter, the receiver detects the signal after eliminating mutual interference using an appropriate signal processing technique. Examples of the interference cancellation scheme include a maximum likelihood (ML) scheme, a ZF (zero forcing) scheme, a minimum mean square error (MMSE) scheme, a diagonal Bell Laboratories Layered Space- Vertical Bell Labs Layered Space-Time) method. When the transmitter can know the channel information, a singular value decomposition (SVD) method or the like can be used.

Third, a hybrid scheme combining spatial diversity and spatial multiplexing can be used. If only the spatial diversity gain is obtained, the performance gain is gradually saturated as the diversity order increases. If only the spatial multiplexing gain is used, the transmission reliability in the wireless channel is lowered. Such a hybrid scheme includes a double-space time diversity (D-STTD) scheme, a space time bit-interleaved coded modulation scheme (STBICM) scheme, and the like.

FIG. 6 is a conceptual diagram illustrating an example of mounting a frame and an antenna mounted on a main body according to embodiments of the present invention, and FIG. 7 is a conceptual diagram showing a connection relationship between a frame and an antenna according to an embodiment of the present invention .

Hereinafter, a MIMO or diversity antenna according to a first embodiment of the present invention will be described with reference to FIGS. 6 and 7. FIG.

In order to smoothly transmit and receive signals in a system equipped with an MIMO or diversity antenna, a first antenna (main antenna at the transmitting or receiving end) and a second antenna (diversity Or the receive-side sub-antenna of the MIMO system), the value of the mutual coupling and the related coefficient (Envelope Correlation Coefficient) must be low.

For example, as a required reception condition, the main antenna operates in the same way as a single receiver, the difference in gain between the two antennas is less than 6 dB, the Envelope Correlation Coefficient (ECC) is 0.5 The use of the main antenna always at the transmitting side, and the antenna to antenna isolation greater than 8 dB are satisfied, it can operate well as a MIMO antenna at the frequency of the LTE band.

Among the above requirements, it is most difficult to implement a MIMO antenna in a mobile terminal by implementing an ECC of 0.5 or less expressing a correlation between two antennas, except for antenna basic performance such as gain (gain) and bandwidth It is a point.

In order to satisfy such a condition, it is necessary that the two antennas are spaced apart by a distance equal to or longer than half a wavelength or that the polarization directions of the two antennas are orthogonal to each other as much as possible. However, for example, in the case of LTE, which is a fourth generation mobile communication, a 700 MHz band is used. In this case, the half-wave length exceeds 400 mm, which may make it difficult to actually divide the two antennas by half a wavelength or more .

Accordingly, in the present invention, a plurality of grounds are formed in a multi-layered frame so that the first antenna and the second antenna are grounded and connected to different grounds, respectively.

Referring to FIGS. 7 and 8, the frame 250 includes a first member 251 and a second member 252 in a plate form. The members constituting the frame 250 may be at least partially formed of a conductive material such as stainless steel (SUS) or a magnesium alloy.

An isolation member 253 for spatially separating the first member 251 and the second member 252 is formed between the first member 251 and the second member 252. The isolation member 253 may be formed of a dielectric material, and may further include an insulator or an electromagnetic wave absorber. The dielectric material can be formed of a dielectric material having a high dielectric constant coefficient of 37 (Q * f 35000), a dielectric constant of 45 (Q * f 40000), a dielectric constant of 60 (Q * f 6000) or a dielectric ceramic having a similar dielectric constant .

The frame 250 may be an intermediate case capable of supporting the inside of the terminal. In this case, a part of the frame 250 may be exposed to the outside. When exposed to the outside, the static electricity inside the terminal may be discharged to the outside.

When the frame 250 is exposed to the outside, it can constitute a ground, and can operate effectively as a part of the ground.

Referring to FIG. 3, a display module 210b may be disposed on a top surface of the frame 250, and a printed circuit board 205 may be disposed on a bottom surface thereof. Various types of electrical elements may be disposed on the printed circuit board 205 as described above.

Since the frame 250 includes the first member 251 and the second member 252, the upper surface of the frame 250 corresponds to one surface of the second member 252, And corresponds to one surface of the member 251. The display module 210b is coupled to one surface of the first member 251 and the printed circuit board 205 is coupled to one surface of the second member 252. [

An antenna element may be disposed on both ends of the frame 250 in the longitudinal direction. The first antenna element 261 may be disposed at one end of the frame 250 and the second antenna element 262 may be disposed at the other end of the frame 250. [ That is, the first antenna is disposed at one end of the terminal body and the second antenna element 262 is disposed at the other end.

The first antenna element 261 is grounded to the first member 251 and the second antenna element 262 is grounded to the second member 252. The first member 251 and the second member 252 are spatially separated from each other by the isolating member 253 and the first member 251 and the second member 252 are connected to the first ground and the second ground The first ground and the second ground are spatially separated to improve the isolation between the first antenna and the second antenna.

Therefore, even if the distance between the first antenna element 261 and the second antenna element 262 is less than 150 mm, the MIMO ECC can be made within 0.5.

For example, even when the distance between the first antenna element 261 and the second antenna element 262 is 100 mm, it is confirmed that the isolation degree is 10.5 dB and the MIMO ECC is 0.48.

The electrical connection between the antenna elements and the respective members can be made by a ground connection. The ground connection portion may include at least two paths having different lengths, and may be formed with a switch corresponding to each path. Also, through a switch for selecting each path, each pass selectively connects the electrical ground and the radiators of each antenna element with different lengths. Here, the path is an electrical path connecting the ground and the radiator, and may include a ground plate, a grounding clip, and a grounding line. Further, the lengths of the paths can be formed differently by forming the ground wires to have different lengths.

The antenna elements and the printed circuit board 205 may be power-connected by a power supply connection. The feed connection unit feeds the respective radiators of the antenna elements to an electric connection (or EM (Electro-Magnetic) feeding method). That is, the radiator is electrically connected to the radiating device formed on the printed circuit board 205.

For this connection, the feed connection portion may be formed including a feed plate, a power supply clip, and a feeder line. Here, the feed plate, the feed clip, and the feeder line are electrically connected to each other to transmit the current (or voltage) fed through the feeder to the conductor of the radiator. Here, the feeder line may include a microstrip printed on the printed circuit board 205.

The spacing between the feed connection and the ground connection can be adjusted for impedance matching, as the bandwidth of the feed connection and the ground connection decreases as they approach each other and the impedance tends to increase as the distance increases.

The first antenna element 261 and the second antenna element 262 may include a plurality of resonant members for operation in a plurality of frequency bands and each resonant member may be formed in the form of IFA, Monopole, dipole, or the like . For example, one may be in the form of a folded dipole and the other in the form of a PIPA. The first antenna element 261 and the second antenna element 262 may be connected to the multilayer circuit board by feed connection or grounding, respectively, according to the respective antenna types.

The first antenna element 261 is preferably formed to have a difference of 3 dB to 6 dB in antenna gain difference compared to the second antenna element 262. Therefore, in an antenna system operating in MIMO or diversity, It can smoothly transmit and receive.

Here, the first antenna element 261 may be a main antenna, and the second antenna element 262 may be a receiving side sub-antenna in a diversity or MIMO system. Alternatively, the second antenna element 262 may be a main antenna, and the first antenna element 261 may be a receiving side sub-antenna in a diversity or MIMO system.

The mobile terminal described above can be applied to not only the configuration and method of the embodiments described above but also all or some of the embodiments may be selectively combined so that various modifications may be made to the embodiments It is possible.

Claims (10)

A plate-like first member and a second member facing each other with an insulating member having a dielectric constant higher than a predetermined value therebetween;
A first antenna element grounded to the first member; And
A second antenna element spaced from the first antenna element and grounded to the second member,
Wherein the first and second antenna elements are configured to operate as multiple input multiple output (MIMO). The method according to claim 1,
Wherein the first and second members are part of a frame to which the display module and the printed circuit board embedded in the terminal are coupled. The method according to claim 1,
A printed circuit board is coupled to one surface of the first member,
And a display module is coupled to one surface of the second member. 3. The method of claim 2,
Wherein at least a part of the frame is exposed to the outside to form an appearance of the terminal. The method according to claim 1,
Wherein the first antenna element is disposed at one end of the terminal body,
And the second antenna element is disposed at the other end of the terminal main body. delete The method according to claim 1,
Wherein an antenna gain difference between the first antenna element and the second antenna element is 3 dB to 6 dB. The method according to claim 1,
Wherein an antenna to antenna isolation between the first antenna element and the second antenna element is at least 8 dB. The method according to claim 1,
Wherein an envelope correlation coefficient (ECC) between the first antenna element and the second antenna element is within 0.5. A terminal body having a frame formed to support the inside thereof; And
A first antenna element and a second antenna element disposed at opposite ends of the frame and spaced apart from each other,
The frame includes:
A first conductive member to which the first antenna element is grounded;
A second conductive member to which the second antenna element is grounded; And
And an isolation member formed between the first conductive member and the second conductive member to spatially separate the first antenna element and the second antenna element.

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