KR20150095010A - Method of communicating for moving objects with high speed and apparatus for performing thereof - Google Patents

Abstract

Disclosed are a communications method for a high-speed moving object and a communications device for performing the same. The method, performed in a terminal, includes the steps of: forming a wireless communications link with a first relaying device; measuring the quality of a signal received from other relaying devices if the channel quality of the first relaying device is same with a reference value or lower; and correcting the beam generation direction of an antenna if a relay device, having the signal quality same with a threshold value or higher, does not exist after comparing the measured signal quality with the predetermined threshold value. Therefore, service quality can be ensured in an environment where the terminal moves at a high speed; and a large-scale data service can be provided.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication method for a high-speed moving object,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication technology, and more particularly, to a communication method for a high-speed mobile body capable of providing a large-capacity communication service to a mobile body in an environment in which the mobile body moves at high speed, and a communication device performing the same.

A cellular-based mobile communication system such as Long Term Evolution (LTE), LTE-Advanced or Worldwide Interoperability for Microwave Access (WiMAX) is not a system designed considering a high-speed mobile object. It is difficult to guarantee the quality of service and it is difficult to provide a large capacity data service. For example, in a conventional cellular-based communication system, when a communication device is located in a moving object moving at a speed of 400 km / h or more like a high-speed train, the wireless transmission speed is remarkably reduced, so that it is difficult to provide a stable data service.

Accordingly, a high-speed wireless transmission system different from a conventional cellular-based mobile communication system is needed to provide a stable and large-capacity data service to a communication apparatus located in a high-speed mobile station such as a high-speed train, a high-speed bus or a subway.

On the other hand, it is difficult to provide a data rate of Gbps or higher using the frequency band used in the conventional cellular mobile communication system. Accordingly, a high-speed wireless transmission technology using a millimeter wave (mmWave) frequency band corresponding to 10 GHz to 300 GHz has been actively developed.

When the millimeter-wave frequency band is used in the radio transmission technology, a wide bandwidth can be obtained, and radio resources and space resources such as time, frequency, and codes can be utilized.

However, the wireless communication using the millimeter wave frequency band has a drawback in that the communication distance is short due to various factors such as rainfall and gas molecules attenuating signals in the atmosphere. In addition, there is a restriction that the line-of-sight (LOS) must be secured due to the intrinsic characteristics of the millimeter-wave frequency band in the wireless communication using the millimeter-wave frequency band.

Therefore, in order to extend the communication distance in the radio communication using the millimeter-wave band, the signal output must be increased or a directional antenna having a high gain must be used. However, in a general wireless communication system, since the maximum output of a signal transmitted from a transmitting apparatus such as a base station is limited, there is a limit to increase the signal output in order to extend the communication distance. As a result, in order to extend the communication distance to a long distance in the radio communication using the millimeter wave band, a directional antenna that can guarantee the gain can be used. That is, in the wireless communication using the millimeter wave frequency band, in order for the base station and the mobile terminal to perform normal communication even at a long distance, the width of the beam radiated from the antenna of each communication device must be narrow.

However, when a directional antenna with a narrow beam width is applied to a base station or a terminal, the communication range of the base station or the terminal is limited to a range within the directional angle of the directional antenna, have.

In addition, when the mobile terminal does not normally receive the beam in the handoff interval, a handoff operation may unnecessarily increase, or communication between the base station and the mobile terminal may be disconnected.

An object of the present invention to solve the above problems is to provide a communication method for a high-speed mobile body that can guarantee a service quality in an environment where a mobile body moves at high speed and can provide a large-capacity data service.

It is another object of the present invention to provide a communication device capable of ensuring service quality in an environment where a moving object moves at high speed and capable of providing a large-capacity data service.

Other objects and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which: FIG.

According to another aspect of the present invention, there is provided a communication method for a high-speed mobile station, the method comprising: forming a wireless communication link with a first relay apparatus; Measuring a quality of a signal received from other relay apparatuses when the channel quality of the first relay apparatus is equal to or less than a preset reference value, comparing the measured signal quality with a preset threshold value, And correcting the beam forming direction of the antenna when the apparatus is not present.

Here, the wireless communication method may further include receiving beam forming direction information of the first relay device from the first relay device after the step of forming a wireless communication link with the first relay device.

Here, the step of receiving the beam forming direction information of the first repeater may include: receiving position information of the first repeater, axis information of the antenna provided in the first repeater, Direction information and at least one beam forming direction information of the direction angle information.

Here, the step of receiving the beam forming direction information of the first relay apparatus may acquire the beam forming direction information of the first relay apparatus through the system information broadcast from the first relay apparatus.

Here, the wireless communication method may further include acquiring at least one beam forming direction information of an axis and direction angle information of an antenna provided in the terminal, from a sensor unit provided in the terminal.

The step of correcting the beam forming direction of the antenna may include the steps of: comparing the beam forming direction information of the first relay apparatus with beam forming direction information of the terminal; and correcting the antenna of the terminal according to the comparison result Calculating a correction value, and correcting an antenna provided in the terminal based on the calculated correction value.

According to another aspect of the present invention, there is provided a communication apparatus for a high-speed mobile communication system including a plurality of antenna units, a plurality of antenna units connected to the plurality of antenna units, And a first relay device connected to the RF processor and configured to form a radio link based on the quality of signals received from the plurality of relay devices, A physical layer processing unit for providing the antenna control signal based on information and a direction of an antenna provided in the first relay apparatus, and a controller for measuring a moving direction of the radio communication apparatus and providing the moving direction information to the physical layer processing unit And a sensor unit.

Here, the plurality of antenna units may include a first antenna unit that transmits and receives a signal using one of polarized waves of vertical and horizontal polarizations, and a second antenna unit that transmits and receives signals using polarized waves different from the polarized waves used by the first antenna unit can do.

The radio communication apparatus may further include a satellite navigation information receiving unit that receives the satellite navigation signal and provides the received satellite navigation signal to the physical layer processing unit, wherein the physical layer processing unit, based on the satellite navigation signal, Time synchronization with one repeater can be performed.

Here, the physical layer processor may receive, from the first relay apparatus, the beam forming direction information of the first relay apparatus, the axis information of the antenna provided in the first relay apparatus, and the direction angle information of the antenna provided in the first relay apparatus At least one beam forming direction information may be provided.

Here, the physical layer processing unit receives at least one direction information of the axis and direction information of the plurality of antenna units from the sensor unit, compares the beam forming direction information of the first repeater and the direction information The antenna control unit may generate the antenna control signals based on the calculated correction values after calculating correction values for correcting the beam forming directions of the plurality of antenna units.

According to the communication method for a high-speed mobile body and the communication device for performing the above-mentioned operations, the mobile station moving at a high speed in a wireless communication environment in which a visible distance is secured can select beams having high signal quality among a plurality of signals received from the high- And corrects the directivity direction of the antenna according to the movement of the terminal so that the directivity direction of the relay device and the directivity direction of the terminal always coincide with each other.

Therefore, it is possible to guarantee the service quality even in an environment where the terminal (or moving body) moves at a high speed, and to provide a large-capacity data service.

1 is a conceptual diagram illustrating a configuration of a wireless communication system using millimeter waves according to an embodiment of the present invention.
2 is a conceptual diagram illustrating an antenna configuration of a relay apparatus according to an embodiment of the present invention.
3 is a conceptual diagram illustrating an antenna configuration of a UE according to an embodiment of the present invention.
4 is a block diagram illustrating a configuration of a terminal according to an embodiment of the present invention.
5 is a block diagram showing the configuration of the physical layer processing unit shown in FIG. 4 in more detail.
6 is a flowchart illustrating an antenna control method of a terminal according to an embodiment of the present invention.
7 is a flowchart illustrating a wireless communication method according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the present invention, the same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

The term 'terminal' used in the present application includes a mobile station (MS), a user equipment (UE), a machine type communication (MTC) device, a mobile terminal (MT) A wireless terminal, an access terminal (AT), a subscriber unit, a subscriber station (SS), a wireless device, a wireless communication device, a wireless transmit / receive unit (WTRU) Receive Unit), mobile node, mobile, or some other terminology.

In particular, the term 'terminal' in the present application may mean a user terminal moving at a high speed or a communication device mounted in a high-speed mobile body moving at high speed such as an automobile, a bus, a train, It can mean a variety of means of transport aboard one user. In the following description, the term " terminal " may be used in combination with the term " mobile body ", and in this case, the term " mobile body " should be understood to mean a communication device or terminal mounted on a mobile body.

The term 'base station' used in the present application is used to mean a control device for controlling one cell. However, in an actual wireless communication system, a physical base station can control a plurality of cells, in which case the physical base station can be regarded as including at least one base station used in the present application.

The 'base station' may be a digital unit, a base station, a node-B, an eNode-B, a base transceiver system (BTS), an access point Point, a transmission point, a relay, a relay node, a femtocell, and the like.

The 'relay device' used in the present application means a device connected to a base station and performing radio transmission / reception of signals, and it may be a radio unit, a remote radio head (RRH) or a remote radio equipment (RRE) Can be referred to as terminology.

A communication method for a high-speed moving object and a communication device performing the same according to embodiments of the present invention will be described below. A terminal (or a moving object) receives directional beams of a relay apparatus and selects an optimal beam to perform communication ≪ / RTI > In particular, when a terminal switches direction or a difference in altitude occurs during a process of selecting an optimal beam among received beams, the terminal automatically corrects the corresponding antenna, thereby providing high-quality two-way communication and seamless wireless Communication is enabled.

1 is a conceptual diagram illustrating a configuration of a wireless communication system using millimeter waves according to an embodiment of the present invention.

1, a wireless communication system according to an embodiment of the present invention includes a gateway 110, a plurality of base stations 120 and 130, and a plurality of relay devices 121, 123, 125, 131, 133, and 135 .

The gateway 110 may be connected to the plurality of base stations 120 and 130 through a physical communication medium and may transmit data transmitted from the base stations 120 and 130 to a wired communication network such as the Internet, To the target BS among the plurality of BSs 120 and 130. Here, the gateway 110 and the plurality of base stations 120 and 130 may be connected to each other through an optical cable.

Each of the plurality of base stations 120 and 130 can perform a base station function of a general mobile system and can communicate with a plurality of relay devices 121 and 123 and a plurality of relay devices 131, And can manage the terminals 150 and 160 (or moving objects).

Each of the base stations 120 and 130 may be configured to be connected to another base station through a specific interface, or may be configured to be fixedly connected to a plurality of relay devices managed by the base stations 120 and 130, The data or control signal provided from the base station may be transmitted to at least one of the plurality of relay apparatuses managed by the relay apparatus or may be transmitted to the other base station or the gateway 110 from the at least one relay apparatus.

The plurality of relay apparatuses 121, 123, 125, 131, 133, and 135 transmit and receive control signals or data to and from the terminals 150 and 160, respectively, In the case where the relay apparatuses 121, 123 and 125 transmit data to the terminal 150, the relay apparatuses 121, 123 and 125 convert the data received from the base station 120, which manages it, into RF signals, When the relay apparatuses 121, 123 and 125 receive data from the terminal 150 via the uplink, the base station 120 that manages the received signal transmits the received signal to the terminal 150, Through an interface configured in advance.

Each of the relay apparatuses 121, 123, 125, 131, 133, and 135 may be installed at a position capable of forming a beam on a moving path of the moving object along a path (for example, a highway or a railroad track) .

An antenna provided in each of the repeaters 121, 123, 125, 131, 133 and 135 forms a beam in a specific direction in consideration of the moving directions 171 and 181 of the terminals 150 and 160 And the like.

For example, as shown in FIG. 1, the relay apparatuses 121, 123, and 125 are installed on one side of the movement path so as to be able to communicate with the moving body 150 moving in the leftward direction 171 of the movement path, The antenna provided in each of the repeaters 121, 123, and 125 may be installed to form a beam in a direction opposite to the moving direction 171 of the moving body 150.

The relay apparatuses 131, 133 and 135 are installed on the other side of the movement path so as to be able to communicate with the mobile body 160 moving in the right direction 181 of the movement path, May be provided so as to form a beam in a direction opposite to the moving direction 181 of the moving body 160.

An antenna installed in each of the repeaters 121, 123, 125, 131, 133, and 135 may be a predetermined range (for example, a horizontal angle of the beam and / or a number of beams) in consideration of the height of the moving object and interference with other relay devices At right angles).

A communication device (or terminal) capable of performing communication with the relay devices may be mounted on the mobile bodies 150 and 160 and may be configured to communicate with the relay devices 121, 123, 125, 131, 133, and 135 At least two antennas may be installed.

Here, the antennas installed on the moving object or the terminal mounted on the moving object can be installed in the direction in which the moving object moves and in the direction opposite to the direction, respectively. For example, when the moving body is an automobile, the antennas can be installed at appropriate positions in the front and rear portions of the automobile.

As described above, according to the embodiment of the present invention, the mobile body moving at a high speed by installing a plurality of antennas in consideration of the moving direction of the mobile body (or terminal) can be moved from the relay devices Signal, thereby improving the data rate or receiving performance.

2 is a conceptual diagram illustrating an antenna configuration of a relay apparatus according to an embodiment of the present invention.

Referring to FIG. 2, the antennas installed in the repeaters 221, 222, 231, and 232 according to the embodiment of the present invention are arranged in a direction opposite to the moving direction of the moving bodies 241 and 242 moving at high speed The direction in which the moving body moves), and may be fixedly installed to have a predetermined beam forming direction and a beam forming angle.

Each of the relay devices 221, 222, 231, and 232 may be installed around the movement path of the moving objects 241 and 242 such as roads and railroad tracks. Since the relay apparatuses 221, 222, 231 and 232 are installed around the moving path of the moving bodies 241 and 242 and are provided so as to form a beam on the moving path, The inter-beam interference transmitted from the plurality of relay devices 221, 222, 231,

In an embodiment of the present invention, the relay apparatuses 221 and 222 provided on one side in the direction crossing the movement path and the relay apparatuses 231 and 232 provided on the other side in order to avoid the inter- So as to form a beam having another polarized wave.

For example, when the relay devices 221 and 222 provided on the left side of the first direction 201 of the movement path shown in FIG. 2 are configured to form beams using vertical polarized waves, The relay devices 231 and 232 provided on the right side of the antenna 211 can be configured to form a beam using horizontal polarization.

Alternatively, when the relay devices 221 and 222 provided on the left side of the first direction 201 form a beam using horizontal polarized waves, the relay devices 231 and 232 provided on the right side of the second direction 211 ) Can be configured to form a beam using vertical polarization.

3 is a conceptual diagram illustrating an antenna configuration of a UE according to an embodiment of the present invention.

Referring to FIG. 3, a terminal (or a moving body) according to an embodiment of the present invention includes an antenna installed at a position capable of efficiently receiving signals transmitted from forward and backward relay devices in a moving direction . That is, the antenna installed in the terminal can be installed at an appropriate position on the outside or inside of the mobile body depending on the type of the mobile body on which the terminal is mounted, the traveling condition, or the situation of the mobile body.

For example, when the moving object is composed of a vehicle, a first antenna 301 may be installed at a front portion of the vehicle, and a second antenna 302 may be installed at a rear portion of the vehicle.

In addition, the plurality of antennas 301 and 302 installed in the terminal can be configured such that each antenna receives signals using different polarizations. For example, if the first antenna 301 is configured to use vertical polarization, the second antenna 302 may be configured to use horizontal polarization, and the first antenna 301 may be configured to use horizontal polarization The second antenna 302 may be configured to use vertical polarization. As described above, in the embodiment of the present invention, the plurality of antennas 301 and 302 provided in the terminal are configured to use different polarizations, so that interference between beams received in different directions can be avoided, The reception performance of the terminal can be improved.

In addition, each of the antennas 301 and 302 installed in the terminal can be configured to radiate the directional beams 311 and 312 in a specific direction. Here, the direction of the directional beams 311 and 312 emitted from the respective antennas can be changed dynamically according to the movement state of the terminal (or moving body) as described later.

Meanwhile, each antenna provided in the terminal may be configured in the form of a phased array antenna to form a beam in a specific direction as described above, and dynamically change the beam forming direction and polarization according to the mobile environment of the terminal. That is, the antenna provided in the terminal can change polarization in accordance with the direction of movement of the terminal, and even when the terminal moves in a curved path or in a section in which a difference in level occurs, The beam forming direction can be dynamically adjusted so as not to cause communication disconnection.

4 is a block diagram illustrating a configuration of a terminal according to an embodiment of the present invention. 5 is a block diagram showing the configuration of the physical layer processing unit shown in FIG. 4 in more detail.

Hereinafter, the configuration of a terminal according to an embodiment of the present invention will be described in detail with reference to FIGs. 4 and 5. FIG.

4, a terminal according to an embodiment of the present invention includes a satellite navigation information receiving unit 410, a sensor unit 420, a plurality of antenna units 430, a plurality of RF processing units 440, A physical layer processing unit 450 and a protocol processing unit 470.

The satellite navigation information receiving unit 410 receives the navigation signals transmitted from the GPS system such as Global Positioning System (GPS), Global Navigation Satellite System (GLONASS), or Galileo, and transmits the received navigation signals to the physical layer processing unit 450 so that the time synchronization between the terminal and the relay apparatus can be performed and position information can be obtained.

When a mobile station moves in a service area (or a serving cell) of a specific relay apparatus while moving on a movement path, the mobile station leaves the serving cell and enters a service area (target cell) of a new relay apparatus , The target cell must be in a state capable of receiving a signal transmitted from a terminal that has newly entered the service area of the target cell. At this time, since the target cell can not know the information on the delay time of the signal transmitted from the mobile station, it measures the reception timing of the serving cell and the target cell, calculates the delay time based on the received timing, Thereby enabling the handover of the terminal while ensuring the service without the service.

Absolute time information is required for time synchronization between the terminal and the relay device as described above. For this purpose, in the present invention, time synchronization is performed using the satellite navigation signal received by the satellite navigation information receiver 410.

The sensor unit 420 may include a gyro sensor and / or a geomagnetic sensor. The sensor unit 420 may detect movement direction (or a change amount of the movement direction) of the terminal or the moving object, and provide the detected orientation information to the physical layer processing unit 450 do. When the terminal (or moving body) moves in a curved section or a ramp during the movement path, the moving direction or altitude of the terminal can be changed. In such a case, the terminal deviates from the directional beam forming range of the relay apparatus, There may be a problem of being disconnected.

In the present invention, in order to prevent the above-described problems, the sensor unit 420 provides the physical layer processing unit 450 with the axis and / or direction angle information changed according to the direction change of the terminal (or the moving object) The direction of the antenna unit 430 is always aligned with the beam forming direction of the relay apparatus by controlling the antenna unit 430 installed in the terminal based on the axis and / or direction angle information provided by the physical layer processing unit 450 .

The plurality of antenna units 430 may be composed of two antenna units, and each antenna unit 430 can dynamically change the direction of the beam based on the control signal of the RF processing unit 440 Phased array antenna.

In addition, each of the antenna units 430 may be configured to transmit and receive signals using different polarizations based on control signals provided from the RF processor 440.

4, each of the antenna units 430 changes the direction and polarization characteristics based on the control signal provided from the RF processor 440. However, the main body that performs the control of each antenna unit 430 The present invention is not limited to the RF processing unit 440 and other components other than the RF processing unit 440 may be configured to perform the control of each antenna unit 430 as described above. For example, in another embodiment of the present invention, the control of each antenna unit 430 may be performed by the physical layer processing unit 450 instead of the RF processing unit 440.

The plurality of RF processing units 440 may have the same number as the number of the antenna units 430 and may be configured to connect one antenna unit 430 and one RF processing unit 440. In FIG. 4, since the antenna unit 430 is illustrated as having two antennas, the RF processor 440 may be formed of two antennas.

Each RF processor 440 can perform a function of processing a signal transmitted or received through a corresponding antenna unit 430 in an RF processor 440 of a general mobile communication device. For example, RF processing converts a digital signal provided from the physical layer processing unit 450 into an analog signal, amplifies the analog signal into a signal with power that can be transmitted through the antenna unit 430, And performs low noise amplification (LNA) on the signal received through the antenna unit 430, converts the signal into digital data, and provides the digital signal to the physical layer processing unit 450 .

The RF processor 440 may perform processing for adjusting the polarization direction or the direction of the antenna unit 430 in accordance with the control signal provided from the physical layer processor 450. [

The physical layer processor 450 can be divided into a physical layer transmitter, a physical layer receiver, and a controller.

The physical layer receiver may include a demodulator 510, a decoder 520, a DOA (Direction of Arrival) measurer 530 and a cell searcher 540. The demodulator 510 may include an OFDM (Orthogonal Frequency Division Multiplexing) A channel estimator 511, a channel estimator 512, a channel corrector 513, and a channel demodulator 514.

The physical layer reception unit processes the signal received from the relay apparatus and transmits the processed signal to the protocol processing unit 470.

A plurality of relay apparatuses may exist in the movement path of the terminal, and the terminal may receive a signal from the plurality of relay apparatuses while moving along the movement path. In an embodiment of the present invention, the physical layer receiver searches an excellent signal whose quality is equal to or higher than a predetermined threshold value among the signals received from the plurality of relay apparatuses as described above, and forms a link with the relay apparatus that transmits the searched signal .

Specifically, the OFDM demodulator 511 of the physical layer receiver performs OFDM demodulation on the signals received from the plurality of relay apparatuses and provides them to the channel measurer 512 and the channel corrector 513, Measures the channel quality of a plurality of OFDM demodulated signals provided from the OFDM demodulator 511 and then provides the measurement results to the channel corrector 513 and the physical layer controller 570. [

The physical layer controller 570 compares the channel measurement information provided from the channel measurer 512 with a preset threshold value, selects a signal having a signal quality of a threshold value or more among the signals received from the plurality of relay devices, (For example, a cell ID) of the relay apparatus corresponding to the relay apparatus, and performs processing for configuring a radio link with the relay apparatus using the acquired unique identification apparatus.

System information may be included in a signal broadcasted from each of a plurality of relay apparatuses (for example, a broadcast channel (BCH)). The system information includes a time (e.g., GPS time) Axis direction angle information of the center of the antenna provided in the relay apparatus, and the time information of the relay apparatus is used for synchronization between the relay apparatus and the terminal and handover without interruption. In addition, the three-axis direction angle information of the antenna center included in the relay apparatus is used to correct the direction of the antenna of the terminal when the terminal (or moving body) moves in a curve section or a slope section and a change occurs in the traveling direction. Here, a signal broadcast from a plurality of relay apparatuses can be received by the cell searcher 540 and provided to the physical layer controller 570.

The physical layer controller 570 compares the direction angle information corresponding to the change in the direction of movement provided from the sensor unit 420 and the direction angle information provided from the relay apparatus to calculate an antenna correction value corresponding to the difference in direction angle, To the RF processor 440, correction information for antenna beamforming so that the beam directing direction of the antenna unit 430 provided in the RF unit 440 coincides with the antenna directing direction of the relay apparatus. Here, the three-axis direction angle information of the antenna included in the relay apparatus may be extracted from the broadcasting signal broadcasted from the relay apparatus or may be calculated based on the radio wave arrival direction measured by the DOA measuring apparatus 530. [

The physical layer receiver demodulates and decodes the received signals provided from the RF processor 440, and provides the demodulated and decoded signals to the protocol processor 470. In particular, the channel corrector 513 of the demodulator 510 performs channel correction on the OFDM demodulated data provided from the OFDM demodulator 511 using the channel measurement information provided from the channel measurer 512, The channel demodulator 514 performs channel demodulation on the data provided from the channel corrector 513 and provides the channel demodulator 514 to the decoder 520.

The decoder 520 decodes the demodulated data provided from the demodulator 510 and provides the demodulated data to the protocol processing unit 470.

The DOA measurer 530 estimates the propagation direction of the received signal based on the signal provided from the RF processor 440, and provides the estimated propagation direction information to the physical layer controller 570. Here, the radio wave arrival direction information may be used to control the beam formation of the antenna unit 430 of the physical layer controller 570, or may be used to calculate the direction difference between the current position of the terminal and the relay apparatus.

The cell searcher 540 continuously acquires synchronization information for cells neighboring a cell (or a serving cell) currently receiving a service based on a signal provided from the RF processor 440, To the controller 570. Here, the cell searcher 540 can acquire frequency and symbol synchronization information for neighboring cells, frame synchronization information of neighboring cells, and physical layer identification information of neighboring cells. Here, the synchronization information provided to the physical layer controller 570 by the cell searcher 540 may be used by the terminal in searching for a new relay apparatus and in linking with a specific relay apparatus.

The physical layer transmission unit encodes and modulates data provided from the protocol processing unit 470, and provides the data to the RF processing unit 440. Specifically, the encoder 550 of the physical layer transmitter encodes the data provided from the protocol processor 470 and provides the encoded data to the modulator 560. The modulator 560 encodes the encoded data supplied from the encoder 550 Lt; / RTI >

On the other hand, since the relay apparatus can receive the signal transmitted from the terminal within the range corresponding to the beam width of the antenna provided in the relay apparatus, the terminal must concentrate the beam in the range of the beam width formed by the antenna of the relay apparatus . In response to the control of the physical layer controller 570, the physical layer transmitter transmits an RF signal to the RF processor 440 in order to transmit a signal to a relay apparatus that transmits a signal of superior quality on the movement path of the mobile station in the signal transmission process on the uplink Lt; / RTI >

Here, the estimation of the relay apparatus for transmitting a signal with a good quality is performed by measuring the signal quality of signals received by the demodulation unit of the physical layer receiver, selecting a channel having the highest quality by the demodulator or the physical layer controller 570, And estimating a relay apparatus corresponding to the selected channel. In addition, the physical layer transmission unit may configure a communication channel by transmitting / receiving a control signal for configuring a link with a relay apparatus having the best channel according to the control of the physical layer controller 570.

Thereafter, the terminal continuously monitors the quality of the channel between the plurality of relay apparatuses, and when the channel quality changes (for example, when the channel quality deteriorates), the terminal continuously monitors the quality of the channel with respect to the other relay apparatuses And prepares handover to another relay apparatus when the channel quality of the other relay apparatus is equal to or greater than the threshold value.

Alternatively, if it is difficult to perform handover to another relay apparatus, the terminal controls the direction of the antenna based on the information provided from the sensor unit 420 in order to perform beam forming in the antenna directing direction of the relay apparatus to which the current link is connected .

FIG. 6 is a flowchart illustrating a method of controlling an antenna of a terminal according to an embodiment of the present invention, and may be performed in a terminal having a configuration as shown in FIG.

Referring to FIG. 6, the terminal measures current position, axis and / or direction information of the terminal through the satellite navigation information receiving unit 410 and the sensor unit 420 (S601).

Also, the terminal acquires the position, axis and / or direction information of the relay device based on the signal transmitted from the relay device (S603). Here, the terminal may acquire the position, axis and direction angle information from the system information included in the broadcast signal transmitted from the relay apparatus, and may estimate the arrival direction of the signal transmitted from the relay apparatus to obtain the information It is possible.

Although it is exemplified in FIG. 6 that S603 is executed after step S601 is executed for convenience of explanation, the order of execution of steps S601 and S603 is not limited to that shown in FIG. 6, and the steps may be executed simultaneously, Step S601 may be executed after S603 is executed first. In addition, steps S601 and S603 may be continuously performed while the wireless communication of the terminal is activated.

Axis, and / or direction angle information of each of the terminal and the relay apparatus through the execution of steps S601 and S603, and compares the obtained information with each other to determine whether the direction of the antenna provided in the terminal matches the direction of the antenna (S605).

Thereafter, if the direction of the antenna of the terminal is not coincident with the direction of the antenna of the repeater, the terminal calculates a correction value for correcting the direction of the antenna of the terminal (S607), and based on the calculated correction value, And controls the antenna unit 430 to correct the direction of the antenna 430 (S609).

7 is a flowchart illustrating a wireless communication method according to an embodiment of the present invention.

First, the terminal periodically searches the relay apparatuses at predetermined time intervals based on the signals received from the plurality of relay apparatuses (S701).

Then, the terminal determines whether there are signals having a magnitude equal to or greater than a preset reference signal level among the signals transmitted from the plurality of relay apparatuses (S703). If it is determined that there is a signal above the reference signal level, And transmits the measurement information to the relay apparatus that has transmitted the signal (S705).

Upon receiving the measurement information from the terminal, the corresponding relay apparatus prepares to form a link with the terminal, and transmits a control signal for link configuration of the relay apparatus to the terminal (S707).

After completing the synchronization, the terminal transmits a control signal indicating that the radio link configuration is completed with the relay device to the relay device (S711) after completing the synchronization process for the radio link connection with the relay device. Here, the relay apparatus having the wireless link with the terminal can be a serving relay apparatus (or serving cell) of the terminal. When a wireless link is established with the relay apparatus, the terminal continuously receives beam forming direction information such as the position of the relay apparatus, the axis of the antenna of the relay apparatus, and / or the direction angle information from the relay apparatus.

Thereafter, the UE continuously monitors the channel quality with the serving repeater and, if the channel quality falls below a predetermined reference quality value, measures the channel quality of the new repeater (S713).

In step S715, the terminal determines whether the channel quality of the new relay apparatus is equal to or greater than a predetermined threshold value. If the channel signal quality of the new relay apparatus is equal to or greater than the threshold value, the terminal performs handover to the new relay apparatus in step S717.

Alternatively, if it is determined in step S715 that the quality of the channel signal of the new relay apparatus is less than or equal to the threshold value, or the new relay apparatus does not exist, the terminal transmits the received signal to the existing relay apparatus (E.g., a serving relay apparatus) in a direction toward the antenna (S719). Herein, the terminal compares the beam forming direction information provided from the existing relay apparatus (i.e., the serving relay apparatus) with the measured axis direction and / or direction angle information, and corrects the beam forming direction of the antenna according to the comparison result After generating the correction value, the beam forming direction can be corrected based on the generated correction value.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It will be possible.

110: gateway 120: base station
121, 123, 125: Relay device 130: Base station
131, 133, 135: Relay device 150, 160: Terminal,
171, 181: moving direction 201: first direction
211: second direction 221, 222, 231, 232: relay device
241, 242: Moving body 302: First antenna
302: second antenna 311, 312: directional beam
410: satellite navigation information receiving unit 420:
430: Antenna unit 440: RF processor
450: physical layer processor 470: protocol processor
510 demodulator 511 OFDM demodulator
512: channel meter 513: channel corrector
514: Channel demodulator 520: Decoder
530: DOA Meter 540: Cell Explorer
550: encoder 560: modulator
570: Physical layer controller

Claims (11)

A method of wireless communication performed in a terminal,
Forming a wireless communication link with the first relay device;
Measuring a quality of a signal received from other relay apparatuses when the channel quality of the first relay apparatus is less than a predetermined reference value; And
And comparing the measured signal quality with a preset threshold value to correct a beam forming direction of the antenna if there is no repeater having a signal quality higher than a threshold value. The method according to claim 1,
The wireless communication method may further include, after the step of forming a wireless communication link with the first relay device,
Further comprising receiving beam forming direction information of the first relay apparatus from the first relay apparatus. The method of claim 2,
Wherein the step of receiving the beam forming direction information of the first relay device comprises:
Wherein the first relay device receives at least one beam forming direction information among position information of the first relay device, axis information of an antenna provided in the first relay device, and direction angle information of an antenna provided in the first relay device Wireless communication method. The method of claim 2,
Wherein the step of receiving the beam forming direction information of the first relay device comprises:
And acquires beam forming direction information of the first relay apparatus through the system information broadcasted from the first relay apparatus. The method of claim 2,
The wireless communication method includes:
Further comprising the step of acquiring at least one beam forming direction information of the axis and direction angle information of the antenna provided in the terminal from the sensor unit provided in the terminal. The method of claim 5,
Wherein the step of correcting the beam forming direction of the antenna comprises:
Comparing the beam forming direction information of the first relay device with the beam forming direction information of the terminal;
Calculating a correction value for correcting the antenna of the terminal according to the comparison result; And
And correcting the antenna provided in the terminal based on the calculated correction value. A wireless communication apparatus comprising:
A plurality of antenna units;
An RF processor connected to the plurality of antenna units and controlling a beam forming direction of the plurality of antenna units according to an antenna control signal;
And determines a first relay apparatus connected to the RF processor and to form a radio link based on the quality of signals received from the plurality of relay apparatuses, A physical layer processing unit for providing the antenna control signal based on a direction of the antenna; And
And a sensor section for measuring the moving direction of the radio communication apparatus and providing the moving direction information to the physical layer processing section. The method of claim 7,
The plurality of antenna units
A first antenna unit for transmitting and receiving signals by using any one of polarizations of vertical and horizontal polarizations; And
And a second antenna unit that transmits and receives a signal using a polarization different from the polarization used by the first antenna unit. The method of claim 7,
The wireless communication device
And a satellite navigation information receiving unit for receiving the satellite navigation signal and providing the received satellite navigation signal to the physical layer processing unit,
Wherein the physical layer processing unit performs time synchronization with the first relay apparatus based on the satellite navigation signal. The method of claim 7,
The physical layer processing unit
The beam forming direction information of the first relay device is transmitted from the first relay device to at least one of a beam forming direction of at least one of axis information of an antenna provided to the first relay device and directional angle information of an antenna provided to the first relay device And the wireless communication device receives the information. The method of claim 7,
The physical layer processing unit
And a controller for receiving the direction information of at least one of the axis and direction angle information of the plurality of antenna units from the sensor unit and comparing the beam forming direction information of the first relay apparatus with the moving direction information, Calculates a correction value for correcting the direction, and generates the antenna control signal based on the calculated correction value.

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