KR20160092387A - Terminal and communication method of the same - Google Patents

Abstract

According to an embodiment of the present invention, a terminal comprises: a communications unit for receiving master information block (MIB) including cell configuration information from a base station; and a control unit for controlling power transmission of a physical random access channel (PRACH) based on the cell configuration information. Therefore, according to an embodiment of the present invention, the terminal and a communications method thereof can reduce interference, crosstalk, and/or an impact among a macro cell, a small cell, and a terminal which can be generated when the terminal is positioned in an area where the macro cell and the small cell are overlapped.

Description

[0001] TERMINAL AND COMMUNICATION METHOD OF THE SAME [0002]

The present invention relates to a terminal and a communication method thereof.

In a wireless communication network environment, a terminal communicates with another terminal through one or more base stations. The base stations may be classified based on coverage (service provision area). The macro cell base station means a general base station of a wireless communication system and has a wide coverage and a high transmission power. The macro cell base station is also referred to as a macro cell. The small cell base station is a small version of a macro cell base station and can operate independently while performing most of functions of a macro cell base station and can be installed in a region covered by a macro cell base station or installed in a shadow area not covered by a macro cell base station . The small cell base station may be referred to as a small cell and may be used as a concept including, for example, a pico cell, a femto cell, a metro cell, a micro cell, do.

On the other hand, since the coverage of the macro cell and the small cell may overlap, the terminal may be located in a region where the cells overlap. In such an environment, interference and collision, which are caused by the mixture of a macro cell having a high transmission power and a small cell having a low transmission power, may be an important problem.

It is an object of the present invention to provide a terminal capable of reducing interference, confusion, and / or collision between a macro cell, a small cell, and a terminal, which may occur when a terminal is located in a region where a macro cell and a small cell overlap, .

The technical problems of the present invention are not limited to the above-mentioned technical problems, and other technical problems which are not mentioned can be understood by those skilled in the art from the following description.

A terminal according to an embodiment of the present invention includes a communication unit for receiving a master information block (MIB) including cell configuration information from a base station, and a control unit for controlling transmission power of a physical random access channel (PRACH) And a control unit.

In one embodiment, the cell configuration information may be defined using the spare bits of the master information block (MIB).

In one embodiment, the extra bit is 10 bits and the cell configuration information may be defined using 1 of the extra bits.

In one embodiment, the cell configuration information may include macro cell information indicating that the cell to which the terminal belongs is a macro cell or small cell information indicating that the cell to which the terminal belongs is a small cell .

In one embodiment, the control unit may decrease the transmission power when the cell configuration information includes the small cell information.

In one embodiment, the cell configuration information includes macro cell information indicating that a cell to which the terminal belongs is a macro cell, femtocell information indicating that a cell to which the terminal belongs is a femto cell, Picocell information indicating that the cell is a pico cell or metro-microcell information indicating that the cell to which the terminal belongs is a metro cell or a micro cell.

In one embodiment, the controller may decrease the transmission power when the cell configuration information includes the femtocell information, the picocell information, or the metro-microcell information.

In one embodiment, the cell configuration information is defined using the spare bits of the master information block (MIB), the spare bits are 10 bits, and the cell configuration information is defined using 2 of the spare bits .

A method for communicating a terminal according to an embodiment of the present invention includes receiving a master information block (MIB) including cell configuration information from a base station, and transmitting a transmission power of a physical random access channel (PRACH) And the like.

In one embodiment, the cell configuration information may include macro cell information indicating that the cell to which the terminal belongs is a macro cell or small cell information indicating that the cell to which the terminal belongs is a small cell .

In one embodiment, controlling the physical random access channel (PRACH) transmission power based on the cell configuration information may reduce the transmission power when the cell configuration information includes the small cell information.

In one embodiment, the cell configuration information is defined using the spare bits of the master information block (MIB), the spare bits are 10 bits, and the cell configuration information is defined using 1 of the spare bits .

In one embodiment, the cell configuration information includes macro cell information indicating that a cell to which the terminal belongs is a macro cell, femtocell information indicating that a cell to which the terminal belongs is a femto cell, Picocell information indicating that the cell is a pico cell or metro-microcell information indicating that the cell to which the terminal belongs is a metro cell or a micro cell.

In one embodiment, the step of controlling the physical random access channel (PRACH) transmission power based on the cell configuration information may include: determining whether the cell configuration information includes the femtocell information, the picocell information or the metro- The transmission power can be reduced.

In one embodiment, the cell configuration information is defined using the spare bits of the master information block (MIB), the spare bits are 10 bits, and the cell configuration information is defined using 2 of the spare bits .

A terminal and a communication method thereof according to an embodiment of the present invention can prevent interference, confusion, and / or collision between a macro cell, a small cell, and a terminal, which may occur when a terminal is located in a region where a macro cell and a small cell overlap, Can be reduced.

1 is a block diagram illustrating a UE according to an embodiment of the present invention.
2 and 3 are views for explaining cell configuration information according to an embodiment of the present invention.
4 is a flowchart illustrating a communication method of a terminal according to an embodiment of the present invention.
5 is a flowchart illustrating a communication method of a terminal according to an exemplary embodiment of the present invention.
6 illustrates a communication connection method between a terminal and a base station including a communication method of a terminal according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals whenever possible, even if they are shown in different drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the difference that the embodiments of the present invention are not conclusive.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. Also, unless otherwise defined, 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.

In the following description, it is assumed that the terminal collectively refers to a mobile or fixed type user terminal device such as a UE (User Equipment) or an MS (Mobile Station). The terminal includes a mobile terminal, a tablet PC A smart phone, a digital camera, a portable multimedia player (PMP), a media player, a portable game terminal, and a PDA (Personal Digital Assistant). It is assumed that the base station collectively refers to any node of a network end that communicates with a terminal such as a Node B, an eNode B, and a base station.

Also, in a mobile communication system, a user equipment can receive information from a base station through a downlink, and a terminal can also transmit information through an uplink. The information transmitted or received by the terminal includes data and various control information, and various physical channels exist depending on the type of information transmitted or received by the terminal.

It is to be understood that the following embodiments assume communication between a terminal and a base station in an LTE (Long Term Evolution) system, but this is merely exemplary and the embodiments of the present invention are limited to LTE systems It is not.

1 is a block diagram illustrating a UE according to an embodiment of the present invention. 2 and 3 are views for explaining cell configuration information according to an embodiment of the present invention.

Referring first to FIG. 1, it is assumed that a terminal 100 according to an embodiment of the present invention communicates with a base station (not shown) in a heterogeneous network environment. For example, a heterogeneous network environment may mean a network environment in which a macro cell and a small cell coexist, and a cell may mean a communication range of a base station. It is assumed that the terminal 100 is located in a region where the macro cell and the small cell overlap.

The terminal 100 may include a communication unit 110 and a control unit 120.

The communication unit 110 may receive a master information block (MIB) including cell configuration information from the base station. For example, the cell configuration information may be information on a cell provided by the base station. In addition, in one aspect, the cell configuration information may be information on a cell to which the UE 100 belongs.

Referring to FIG. 2, the cell configuration information I1 can be defined using the spare bits of the master information block (MIB) (B1).

The master information block (MIB) may include a 24-bit field. The 24-bit field of the master information block (MIB) contains 14 bits of information and may have 10 bits of spare bits. The 14 bits of information may be used to transmit 3 bits of downlink bandwidth (dl-Bandwidth), 3 bits of PHICH (Physical Conjugator Channel) related information (PhicConfig), and 8 bits of SFN (SystemFrameNumber). For more details, refer to 3GPP TS 36.331 V11.7.0.

The cell configuration information may be defined using one of the spare bits of the master information block (MIB). In this case, for example, the cell configuration information includes macrocell information (macrocell) indicating that the cell to which the UE 100 belongs is a macro cell, or small cell information (smallcell) indicating that the cell to which the UE 100 belongs is a small cell . For example, the macro cell information may be set to have a bit value of '0' and the small cell information may have a bit value of '1', but the present invention is not limited thereto. For example, the macro cell information may be set to have a bit value of '1', and the small cell information may have a bit value of '0'.

Referring to FIG. 3, the cell configuration information 12 can be defined using 2 of the spare bits of the master information block (MIB) (B2). In this case, for example, the cell configuration information includes macrocell information (macrocell) indicating that the cell to which the UE 100 belongs is a macro cell, femtocell information indicating that the cell to which the UE 100 belongs is a femtocell, Picocell information indicating that the cell to which the terminal 100 belongs is a picocell or metro-microcell information indicating that the cell to which the terminal 100 belongs is a metro cell or a micro cell. For example, each of the macro cell information, the femtocell information, the pico cell information, and the metro-micro cell information may be appropriately set to have one of the bit values of '11', '10', '01', and '00' Can be set.

Referring back to FIG. 1, the controller 120 may control a transmission power of a Physical Random Access Channel (PRACH) based on the cell configuration information.

For example, the control unit 120 may decrease the transmission power of the physical random access channel (PRACH) when the cell configuration information includes small cell information. Also, for example, the controller 120 may decrease the transmission power of the physical random access channel (PRACH) when the cell configuration information includes femtocell information, picocell information, or metro-microcell information.

As described above, the UE 100 according to an embodiment of the present invention receives a master information block (MIB) including cell configuration information received from a base station, and generates a small cell (PRACH) is transmitted with a lower transmission power for a cell, a pico cell, a metocell, a micro cell, or the like, which occurs when the terminal 100 is located in a region where macro cells and small cells overlap Interference, crosstalk, and / or collision between the macro cell, the small cell, and the terminal 100 that can be performed.

4 is a flowchart illustrating a communication method of a terminal according to an embodiment of the present invention. 5 is a flowchart illustrating a communication method of a terminal according to an exemplary embodiment of the present invention.

4, a method for communicating a terminal according to an embodiment of the present invention includes receiving (S110) a master information block (MIB) including cell configuration information from a base station (S110) And controlling transmission power of the physical random access channel (PRACH) (S120).

Hereinafter, steps S110 and S120 described above will be described in more detail with reference to Figs.

In step S110, the communication unit 110 may receive a master information block (MIB) including cell configuration information from the base station. The cell configuration information may be defined using 1 bit or 2 bits of the 10-bit spare bits of the master information block (MIB). For example, when the cell configuration information is defined using one of the spare bits of the master information block (MIB), the cell configuration information may include macro cell information or small cell information. Also, for example, when the cell configuration information is defined using 2 bits of the spare bits of the master information block (MIB), the cell configuration information includes macrocell information, femtocell information, picocell information, Information.

In step S120, the controller 120 may control the transmission power of the physical random access channel (PRACH) based on the cell configuration information included in the master information block (MIB).

5, in operation S120, it is determined whether small cell information is included in the cell configuration information (S121). When small cell information is included in the cell configuration information, (S122) of the transmission power of the PRACH.

On the other hand, if the cell configuration information is defined by using 2 bits of the spare bits of the master information block (MIB), the small cell information of step S121 and step S122 may include femtocell information, picocell information, and metro- Can be understood as including the concept.

6 illustrates a communication connection method between a terminal and a base station including a communication method of a terminal according to an embodiment of the present invention.

6 illustrates a radio resource control connection procedure between the AT 100 and the BS 200 in order to facilitate understanding of the communication method of the AT according to an embodiment of the present invention.

The RRC connection process between the UE 100 and the BS 200 in the LTE system proceeds as follows. When the synchronization signals PSS and SSS are transmitted from the base station 200 to the AT 100 in step S10, the AT 200 acquires a physical layer identity ( _NID2 ) value from the PSS, And acquires a physical layer cell identity group ( _NID1 ) value. The physical layer cell ID group ( _NID1 ) may have a value from 0 to 167, and the physical layer ID ( _NID2 ) may have a value from 0 to 2. The cell ID may have a value ranging from 0 to 503, and the UE 100 may acquire a cell ID through a cell search process.

The terminal 100 estimates a channel for the communication environment with the base station 100 using the cell-specific reference signal transmitted from the base station 200 and uses the channel for demodulation of the reception channel S11).

The terminal 100 receives system information (System Information) from the base station 200 (S12). In the LTE system, the system information may include a master information block and one or more system information blocks. The master information block (MIB) includes basic parameters for the terminal 100 to access the base station 200, i.e., a cell, and is repeatedly transmitted on a logical channel (BCH) at a period of 40 ms, Channel (BCH) into four equal parts and transmitted on a physical broadcast channel (PBCH) physical channel in units of 10 ms. Meanwhile, according to the embodiments of the present invention described above, the master information block (MIB) may include cell configuration information. The terminal 100 acquires cell synchronization for the base station 200 based on a system frame number of 10 ms.

The terminal 100 receives a control format indicator (CFI) from the base station 200 (S13). The control format indicator CFI informs the number of orthogonal frequency division multiplexing (OFDM) symbols of a physical downlink control channel (PDCCH) to be transmitted. The terminal 100 transmits an OFDM symbol of a PDCCH and a Physical Downlink Shared Channel (PDSCH) It is used for channel demodulation.

The terminal 100 that has acquired the cell synchronization using the parameters received from the master information block (MIB) receives the SIB1 message from the base station 200 (S50). The SIB1 includes information related to the cell connection, The remaining SIBs (SIB2 to SIBn) include scheduling information. Among SIBs other than SIB1, SIBs having the same transmission period are included in the same system information message and transmitted (S14).

The terminal 100 can control the transmission power of the physical random access channel (PRACH) based on the cell configuration information included in the master information block (MIB) (S15).

The terminal 100 that has acquired the necessary information for communicating with the base station 200 through steps S10 to S15 transmits a RA-RNTI (Radio Access Network Temporary (R-RNTI)) message to the base station 200 (PRACH) using a physical random access channel (ID) (S16).

The base station 200 decodes the preamble of the physical random access channel (PRACH) transmitted from the UE 100 and identifies the RA-RNTI used by the UE 100. The base station 200 transmits a random access response (RAR) message in which a Temporary C-RNTI (Cell Radio Network Temporary Identity) is allocated for use by the UE 100 using the RA-RNTI, RR message and acquires uplink resource allocation for transmitting an RRC connect request message (S17).

In order to inform the base station 200 of its own information, the UE 100 transmits an RRC connection request message to the base station 200 using the Temporary C-RNTI obtained from the RAR message (S18).

The base station 200 transmits related information to the terminal 100 so that the terminal 100 can communicate with the base station 200. The base station 200 transmits an RRC connection setup message to the terminal 100 in response to the RRC connection request, 100), and the terminal 100 acquires the C-RNTI from the RRC connection setup message (S19). When the terminal 100 is in the RRC Connected state, the base station 200 and the terminal 100 can exchange messages using the C-RNTI.

When the basic setup for communication between the BS 200 and the MS 100 is completed, the MS 100 transmits a NAS attach request message together with an RRC connection setup completion message using the C-RNTI in step S20. The NAS (Non Access Stratum) is a functional layer for transmitting and receiving signaling and traffic messages between the AT 100 and the core network.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100: terminal
110:
120:
200: base station

Claims (15)

A communication unit for receiving a master information block (MIB) including cell configuration information from a base station; And
And a control unit for controlling transmission power of a physical random access channel (PRACH) based on the cell configuration information. The method according to claim 1,
Wherein the cell configuration information is defined using a spare bit of the master information block (MIB). 3. The method of claim 2,
Wherein the spare bits are 10 bits and the cell configuration information is defined using 1 of the spare bits. The method according to claim 1,
Wherein the cell configuration information includes macro cell information indicating that a cell to which the terminal belongs is a macro cell or small cell information indicating that the cell to which the terminal belongs is a small cell. 5. The method of claim 4,
Wherein the controller decreases the transmission power when the cell configuration information includes the small cell information. The method according to claim 1,
The cell configuration information includes macro cell information indicating that a cell to which the terminal belongs is a macro cell, femtocell information indicating that a cell to which the terminal belongs is a femto cell, pico cell information indicating that the cell belonging to the terminal is a pico cell or metro-microcell information indicating that the cell to which the terminal belongs is a metro cell or a micro cell. The method according to claim 6,
Wherein the control unit decreases the transmission power when the cell configuration information includes the femtocell information, the picocell information, or the metro-microcell information. The method according to claim 6,
Wherein the cell configuration information is defined using a spare bit of the master information block (MIB), the spare bit is 10 bits, and the cell configuration information is defined using 2 of the spare bits. . Receiving a master information block (MIB) containing cell configuration information from a base station; And
And controlling transmission power of a physical random access channel (PRACH) based on the cell configuration information. 10. The method of claim 9,
Wherein the cell configuration information includes macro cell information indicating that the cell to which the terminal belongs is a macro cell or small cell information indicating that the cell to which the terminal belongs is a small cell. Way. 11. The method of claim 10,
Wherein the controlling of the physical random access channel (PRACH) transmission power based on the cell configuration information decreases the transmission power when the cell configuration information includes the small cell information. 10. The method of claim 9,
Wherein the cell configuration information is defined using a spare bit of the master information block (MIB), the spare bit is 10 bits, and the cell configuration information is defined using 1 bit of the spare bits. . 10. The method of claim 9,
The cell configuration information includes macro cell information indicating that a cell to which the terminal belongs is a macro cell, femtocell information indicating that a cell to which the terminal belongs is a femto cell, pico cell information indicating that the cell belonging to the terminal is a pico cell or metro-microcell information indicating that a cell to which the terminal belongs is a metro cell or a micro cell. 14. The method of claim 13,
Wherein the step of controlling the transmission power of the physical random access channel (PRACH) based on the cell configuration information comprises: if the cell configuration information includes the femtocell information, the picocell information or the metro-microcell information, When the number of times of communication is less than a predetermined value. 15. The method of claim 14,
Wherein the cell configuration information is defined using a spare bit of the master information block (MIB), the spare bit is 10 bits, and the cell configuration information is defined using 2 of the spare bits. .

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