KR20160005307A - Methods for measuring the channels and Apparatuses thereof - Google Patents

Abstract

The present invention relates to a channel measuring method used by a terminal and a method thereof. More specifically, the method and the device are used to detect and measure a channel through an unlicensed spectrum. The method includes the following steps: receiving measurement configuration information for searching and measuring cells from a base station; receiving a reference signal being transmitted from the cells based on the measurement configuration information; and using the measurement configuration information and the reference signal to search cells and measure a channel status. The cells use a frequency in the unlicensed spectrum shared by one or more communication systems.

Description

[0001] METHOD FOR MEASURING CHANNEL AND APPARATUS [0002]

The present invention relates to a channel measurement method and apparatus for a terminal. More particularly, the present invention provides a method and apparatus for detecting and measuring channels through an unlicensed spectrum.

As the communication system evolved, consumers such as businesses and individuals became using a wide variety of wireless terminals. The current mobile communication system such as LTE (Long Term Evolution) and LTE-Advanced of the 3GPP series is a high-speed and large-capacity communication system capable of transmitting and receiving various data such as video and wireless data beyond voice- It is required to develop a technique capable of transmitting large-capacity data in accordance with the above-described method. On the other hand, techniques are being discussed which allow carrier merging to be applied to various deployment scenarios as a result of the introduction of multiple cells or small cell deployments.

On the other hand, the carrier merging technique is a technique for merging one or more element carriers to transmit and receive data to improve the data transmission / reception ratio. In the terminal, the available frequency is increased and high-capacity data can be processed at a high speed.

However, the frequency for the mobile communication network is limited, and there is a limitation in providing a high-speed large-capacity data transmission / reception rate to a large number of users in a situation where the number of mobile communication subscribers is increased.

In addition, different frequency bands are used by different wireless communication systems depending on the policy, resulting in poor compatibility.

In order to solve the above-described problems, the present invention proposes a specific method for preventing interference of signals when different wireless communication systems transmit and receive data using the same frequency band.

Also, the present invention proposes a method and apparatus for providing a mobile communication service using a frequency band that can be shared by a plurality of users.

According to another aspect of the present invention, there is provided a method for measuring a channel, the method comprising: receiving measurement configuration information for cell search and measurement from a base station; receiving a reference signal transmitted from the cell based on measurement configuration information; And measuring a cell search or channel condition using the measurement configuration information and the reference signal, wherein the cell is a cell using a frequency of an unlicensed band shared by one or more communication systems.

The method includes the steps of generating measurement configuration information for cell search and measurement, transmitting measurement configuration information, and transmitting measurement configuration information and a reference signal transmitted from the cell, Wherein the cell is a cell using an unlicensed band frequency shared by one or more communication systems. ≪ RTI ID = 0.0 > A < / RTI >

The present invention also provides a terminal for measuring a channel, comprising: a receiving unit for receiving measurement configuration information for cell search and measurement from a base station, receiving a reference signal transmitted from a cell based on measurement configuration information, Wherein the cell is a cell using a frequency of an unlicensed band shared by one or more communication systems, and a controller for measuring a cell search or channel status using a signal.

According to another aspect of the present invention, there is provided a base station for controlling channel measurement of a terminal, the base station including a control unit for generating measurement configuration information for cell search and measurement, a transmitter for transmitting measurement configuration information, And a receiving unit receiving the measured channel state measurement information from the terminal, wherein the cell is a cell using an unlicensed band frequency shared by one or more communication systems.

As described above, the present invention provides an effect of preventing signal interference and transmitting a large amount of data at a high speed when different wireless communication systems transmit and receive data using the same frequency band.

In addition, the present invention provides an effect of preventing ambiguity of a terminal when carrier merging is performed using a license-exempt band frequency.

1 is an exemplary diagram illustrating a reference signal resource mapping in a conventional mobile communication system.
2 is a diagram illustrating an example of measurement configuration information for an LTE / LTE-Advanced cell.
3 is a diagram for explaining a terminal operation in which communication can be performed using the license-exempt band frequency resource of the present invention.
4 is a diagram illustrating a signal flow according to an embodiment of the present invention.
5 is a view for explaining a terminal operation according to another embodiment of the present invention.
6 is a diagram for explaining a terminal operation according to another embodiment of the present invention.
7 is a view for explaining a base station operation according to another embodiment of the present invention.
8 is a view for explaining a base station operation according to another embodiment of the present invention.
9 is a diagram illustrating a terminal configuration according to another embodiment of the present invention.
10 is a diagram illustrating a base station configuration according to another 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 present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

The wireless communication system in the present invention is widely deployed to provide various communication services such as voice, packet data and the like. A wireless communication system includes a user equipment (UE) and a base station (BS, or eNB). The user terminal in this specification is a comprehensive concept of a terminal in wireless communication. It is a comprehensive concept which means a mobile station (MS), a user terminal (UT), an SS (User Equipment) (Subscriber Station), a wireless device, and the like.

A base station or a cell generally refers to a station that communicates with a user terminal and includes a Node-B, an evolved Node-B (eNB), a sector, a Site, a BTS A base transceiver system, an access point, a relay node, a remote radio head (RRH), a radio unit (RU), and a small cell.

That is, in the present specification, a base station or a cell has a comprehensive meaning indicating a part or function covered by BSC (Base Station Controller) in CDMA, Node-B in WCDMA, eNB in LTE or sector (site) And covers various coverage areas such as megacell, macrocell, microcell, picocell, femtocell and relay node, RRH, RU, and small cell communication range.

Since the various cells listed above exist in the base station controlling each cell, the base station can be interpreted into two meanings. i) the device itself providing a megacell, macrocell, microcell, picocell, femtocell, small cell in relation to the wireless region, or ii) indicating the wireless region itself. i indicate to the base station all devices that are controlled by the same entity or that interact to configure the wireless region as a collaboration. An eNB, an RRH, an antenna, an RU, an LPN, a point, a transmission / reception point, a transmission point, a reception point, and the like are exemplary embodiments of a base station according to a configuration method of a radio area. ii) may indicate to the base station the wireless region itself that is to receive or transmit signals from the perspective of the user terminal or from a neighboring base station.

Therefore, a base station is collectively referred to as a base station, collectively referred to as a megacell, macrocell, microcell, picocell, femtocell, small cell, RRH, antenna, RU, low power node do.

Herein, the user terminal and the base station are used in a broad sense as the two transmitting and receiving subjects used to implement the technical or technical idea described in this specification, and are not limited by a specific term or word. The user terminal and the base station are used in a broad sense as two (uplink or downlink) transmitting and receiving subjects used to implement the technology or technical idea described in the present invention, and are not limited by a specific term or word. Here, an uplink (UL, or uplink) means a method of transmitting / receiving data to / from a base station by a user terminal, and a downlink (DL or downlink) .

There are no restrictions on multiple access schemes applied to wireless communication systems. Various multiple access schemes such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), OFDM-FDMA, Can be used. An embodiment of the present invention can be applied to asynchronous wireless communication that evolves into LTE and LTE-Advanced via GSM, WCDMA, and HSPA, and synchronous wireless communication that evolves into CDMA, CDMA-2000, and UMB. The present invention should not be construed as limited to or limited to a specific wireless communication field and should be construed as including all technical fields to which the idea of the present invention can be applied.

A TDD (Time Division Duplex) scheme in which uplink and downlink transmissions are transmitted using different time periods, or an FDD (Frequency Division Duplex) scheme in which they are transmitted using different frequencies can be used.

In systems such as LTE and LTE-Advanced, the uplink and downlink are configured on the basis of one carrier or carrier pair to form a standard. The uplink and the downlink are divided into a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator CHannel (PCFICH), a Physical Hybrid ARQ Indicator CHannel, a Physical Uplink Control CHannel (PUCCH), an Enhanced Physical Downlink Control Channel (EPDCCH) Transmits control information through the same control channel, and is configured with data channels such as PDSCH (Physical Downlink Shared CHannel) and PUSCH (Physical Uplink Shared CHannel), and transmits data.

On the other hand, control information can also be transmitted using EPDCCH (enhanced PDCCH or extended PDCCH).

In this specification, a cell refers to a component carrier having a coverage of a signal transmitted from a transmission point or a transmission point or transmission / reception point of a signal transmitted from a transmission / reception point, and a transmission / reception point itself .

The wireless communication system to which the embodiments are applied may be a coordinated multi-point transmission / reception system (CoMP system) or a coordinated multi-point transmission / reception system in which two or more transmission / reception points cooperatively transmit signals. antenna transmission system, or a cooperative multi-cell communication system. A CoMP system may include at least two multipoint transmit and receive points and terminals.

The multi-point transmission / reception point includes a base station or a macro cell (hereinafter referred to as 'eNB'), and at least one mobile station having a high transmission power or a low transmission power in a macro cell area, Lt; / RTI >

Hereinafter, a downlink refers to a communication or communication path from a multipoint transmission / reception point to a terminal, and an uplink refers to a communication or communication path from a terminal to a multiple transmission / reception point. In the downlink, a transmitter may be a part of a multipoint transmission / reception point, and a receiver may be a part of a terminal. In the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of multiple transmission / reception points.

Hereinafter, a situation in which a signal is transmitted / received through a channel such as PUCCH, PUSCH, PDCCH, EPDCCH, and PDSCH is expressed as 'PUCCH, PUSCH, PDCCH, EPDCCH and PDSCH are transmitted and received'.

In the following description, an indication that a PDCCH is transmitted or received or a signal is transmitted or received via a PDCCH may be used to mean transmitting or receiving an EPDCCH or transmitting or receiving a signal through an EPDCCH.

That is, the physical downlink control channel described below may mean a PDCCH, an EPDCCH, or a PDCCH and an EPDCCH.

Also, for convenience of description, EPDCCH, which is an embodiment of the present invention, may be applied to the portion described with PDCCH, and EPDCCH may be applied to the portion described with EPDCCH according to an embodiment of the present invention.

Meanwhile, the High Layer Signaling described below includes RRC signaling for transmitting RRC information including RRC parameters.

The eNB performs downlink transmission to the UEs. The eNB includes a physical downlink shared channel (PDSCH) as a main physical channel for unicast transmission, downlink control information such as scheduling required for reception of a PDSCH, A physical downlink control channel (PDCCH) for transmitting scheduling grant information for transmission in a Physical Uplink Shared Channel (PUSCH). Hereinafter, the transmission / reception of a signal through each channel will be described in a form in which the corresponding channel is transmitted / received.

The present invention relates to an operation method when a terminal performs carrier merging (or dual connectivity) of LTE or LTE-Advanced radio cells operating in a license band or cells in a license and a license-exempt band. In particular, the present invention relates to a specific method for performing discovery of an LTE / LTE-A radio cell formed in a license-exempt band in a terminal and performing cell measurement for downlink channel measurement for the cell.

The license-exempted bandwidth in this specification refers to a frequency band shared by a wireless communication system other than a frequency band used exclusively in a mobile communication system such as LTE / LTE-A. That is, a cell using a license-exempt band frequency means a cell using a frequency band that can be used by one or more communication systems. Therefore, the license-exempt band is not a frequency band that is exclusively used by a specific communication system or a specific network operator but refers to a frequency band shared by a plurality of communication systems or a plurality of operators.

1 is an exemplary diagram illustrating a reference signal resource mapping in a conventional mobile communication system.

In the LTE / LTE-A Release-10, the carrier merging technique for improving the data rate of the UE has been introduced, so that procedures related to the mobility management of the UE, such as handover and cell selection / reselection procedure, as well as a downlink reference signal measurement operation for performing various operations. For example, the UE may perform cell search / measurement (cell search or measurement) necessary to support carrier merging procedures such as Scell (secondary serving cell) addition / release, Scell activation / deactivation, Measurement) is also performed based on the RRM measurement result of the UE based on the downlink reference signal. Accordingly, all the LTE / LTE-Advanced Release-10 or higher base stations forming a plurality of cells through a plurality of frequency bands have to transmit downlink reference signals in all the cells configured through respective frequency bands. For example, the BS measures one or two CRS (Cell Specific Reference Signal) in all downlink subframes according to the number of downlink transmission antenna ports supported by the corresponding cell for RRM measurement of the UE, as shown in FIG. 1 I had to transfer. However, in a downlink subframe set with a MBSFN (Multicast-broadcast single-frequency network) subframe, the corresponding CRS is transmitted only through the first OFDM symbol or the second OFDM symbol of the first slot.

Accordingly, the UE receives the CRS transmitted through each downlink subframe for a predetermined time, measures RSRP (Reference Signal Received Power) / RSRQ (Reference Signal Received Quality), and reports it to the BS. Release / activation / deactivation (addition / deletion) of a secondary serving cell for carrier merging as well as whether a mobility management procedure such as handover is performed based on reporting information received from a network side activation / deactivation).

Specifically, the UE acquires downlink synchronization using a PSS / SSS-based downlink signal transmitted through a downlink subframe in each cell for searching / measuring for neighboring cells. Also, when the downlink synchronization is obtained, the UE receives the CRS and performs RSRP or RSRQ measurement. The BS receives the measurement result measured by the UE using the CRS and determines whether the UE merges the carriers.

Meanwhile, the base station can transmit the measurement configuration information on the SCell configured in the corresponding base station to the mobile station through the upper layer signaling (e.g., RRC signal) to assist the SCELL search / measurement, which is the basis of performing the carrier merging .

2 is a diagram illustrating an example of measurement configuration information for an LTE / LTE-Advanced cell.

Referring to FIG. 2, when a BS transmits measurement configuration information for SCell search or measurement of a UE, information elements included in the measurement configuration information can be identified. For example, the measurement configuration information may be transmitted in an RRCConnectionReconfiguration message, and the information is measurement configuration information for an LTE / LTE-Advanced (E-UTRA) cell.

Meanwhile, in the case of the LTE-A Rel-12 system, a small cell on / off operation is newly introduced. In addition, a new type of Discovery Reference Signal (DRS) has been introduced for small cell measurements to support small cell on / off operation. That is, CRS is transmitted in all downlink subframes for RRM measurement of a certain cell up to the existing LTE Rel-11 system, and the UE performs CRS-based RRM measurement. However, in the case of Rel-12, when there is no terminal connected to any small cell or there is no data traffic, a semi-static or dynamic small cell on / Off operation. That is, research is underway on cells that perform on / off mode switching dynamically at a subframe level or a radio frame level for an arbitrary cell, or switching on / off modes semi-staticly. In particular, there is a need for a small cell on / off operation that supports off-mode operation that does not perform existing downlink PSS / SSS, CRS or other downlink signals and channel transmissions in order to prevent signal interference and overall system power consumption Was raised. When an on / off mode conversion operation is supported in an arbitrary small cell BS, the CRS for downlink channel measurement is not transmitted in all downlink subframes when the corresponding small cell is in an off state. Therefore, there is a need to define new DRS and search / measurement procedures to ensure discovery performance of the terminal for the corresponding small cell. Accordingly, in the case of a base station supporting cell on / off, DRS configured with PSS / SSS and CRS is set to support the search / measurement of a terminal for a cell formed by the corresponding base station, or PSS / SSS, DRS configured with CSI-RS can be configured.

The DRS can be defined to be able to transmit DRS occasion and DRS opportunity cycle through the DRS Measurement Timing Configuration (DMTC) to the UE through RRC signaling. For example, the DRS described above refers to N consecutive subframes in which DRS transmission is performed.

< In the license-exempt zone LTE  Connection using communication technology ( Licensed Assisted Access  using LTE in unlicensed spectrum )>

Mobile telecommunication carriers in each country constitute a wireless cell by exclusively using licensed spectrum frequencies licensed from the government, and provide wireless communication services to the user terminals based on the constitution. Therefore, it is desired to provide high spectral efficiency through technologies such as MIMO, ICIC and CoMP with a radio access technology (RAT) for efficiently using a limited frequency band. In addition, Carrier Aggregation (CA) technology capable of supporting a higher data rate by merging a plurality of carriers existing in a continuous or non-continuous frequency band has been studied.

However, with the recent introduction of mobile devices with high processing power, including smartphones and tablets, mobile traffic of users is rapidly increasing. Therefore, each wireless communication service provider needs a plurality of frequency resources in order to cover the improved mobile traffic. However, licensed band frequency resources are limited or there is a limit depending on the policy situation of each country.

In this situation, there is a growing need to provide LTE / LTE-Advanced services through an unlicensed spectrum, which is used for providing short-range wireless communication services such as WiFi and Bluetooth.

However, in the case of license-exempt bands, unlike licensed bands, many users, including individuals within the regulations of each country, are freely available for the provision of wireless telecommunication services, rather than wireless channels exclusively available to arbitrary operators .

Therefore, signal interference and coexistence with other communication systems may occur when LTE / LTE-Advanced services are provided through the license-exempt band. For example, when a mobile communication service such as LTE is to be provided using a license-exempt band, co-existence with various short-range wireless communication protocols such as WiFi, Bluetooth, NFC, Problems can arise. In addition, co-existence problems may occur with each LTE provider. Therefore, a method for solving such a problem is needed.

For example, when providing an LTE / LTE-Advanced service through a license-exempt band, a wireless channel or a power level of a carrier to be used before transmitting a radio signal to avoid interference or collision between the respective wireless communication services ) To support a radio channel access method based on LBT (Listen Before Talk) for determining whether the corresponding radio channel or carrier can be used. In this case, if the specific radio channel or carrier of the unlicensed band is in use by another wireless communication protocol or another service provider, there is a possibility that the LTE / LTE-Advanced service through the corresponding bandwidth may be restricted. Therefore, unlike the LTE / LTE-Advanced service through the licensed band, the user can not guarantee the desired QoS in the LTE / LTE-Advanced service through the license-exempt band.

3 is a diagram for explaining a terminal operation in which communication can be performed using the license-exempt band frequency resource of the present invention.

Referring to FIG. 3, in the case of LTE / LTE-Advanced service through the license-exempted band, a licensed-assisted access method LTE (Carrier Aggregation) Service provision may be considered. In this case, the primary carrier supports the FDD or TDD frame structure through the license band, and the secondary carrier configured through the license-exempt band is used for the downlink only Lt; / RTI &gt; Or a secondary carrier configured through a license-exempt band, it may be a form supporting both the uplink and the downlink. That is, the terminal 300 performs a carrier merge to perform communication, and the primary carrier can process both the uplink and the downlink using the license band that the mobile communication system exclusively uses. Meanwhile, the terminal 300 may process only the downlink dedicated data using the frequency using the license-exempt band as the secondary carrier. Alternatively, the terminal 300 may process both the uplink and downlink data through the secondary carrier.

Hereinafter, for convenience of explanation, a cell configured through the license-exempt band in FIG. 3 is referred to as a license-exclusion band cell. However, this is for convenience of explanation, has no limitation on the name, and should be understood to include all the cells of the mobile communication system using the frequency of the license-exempt band. That is, a license-exempt band cell means a cell that uses the frequency of the license-exempt band shared by one or more communication systems.

The present invention relates to a specific method for a terminal to search for a license-unlicensed band cell and perform channel measurement when the base station uses an unlicensed band cell. This is an operation required for improving the communication efficiency since the license-exempt band cell is shared by a plurality of communication systems.

Specifically, in order to support the search or measurement of a terminal for a license-exempt band cell, the corresponding license-exempt band cell must also transmit a downlink reference signal through the downlink sub-frame. However, unlike a cell using a licensed band, a license-exempted band cell has a problem in supporting a fixed type of frame structure due to interference or collision problems with other wireless access technologies or license-unlicensed band cells of other mobile communication providers .

That is, in the case of the licensed band, since the frequency band can be exclusively used by the service provider allocated to the corresponding band, a frame structure (for example, FDD or TDD) Accordingly, it is possible to transmit PSS / SSS and CRS for cell search or measurement of UE through all downlink subframes. Also, in the case of a Rel-12 or higher cell supporting dynamic small cell on / off, a periodic DRS transmission subframe through the DMTC can be ensured.

On the other hand, in the case of the license-exempt band cell, since the frequency of the unlicensed spectrum is shared with other carriers or other communication systems, the downlink sub-frame for transmitting the reference signal for searching or measuring the license- It is difficult to set. In the present invention, the DL reference signal for searching or measuring the license-exempt band is referred to as U-DRS or reference signal.

Therefore, in order to search or measure the license-exempt band cell, a CRS-based search or measurement procedure transmitted through PSS / SSS periodically transmitted and all downlink subframes such as Rel-11 cell search or measurement procedure described above Or a semi-static DMTC based cell search or measurement procedure set through RRC signaling defined in Rel-12 is difficult to apply.

That is, when a license-exempted band cell using an unlicensed spectrum is formed by any of the above-mentioned businesses, it is possible to transmit U-DRS which is a reference signal for searching or measuring a license- It is difficult to secure downlink subframes periodically. Accordingly, cell search or measurement based on measurement configuration information through higher layer signaling applied in existing systems is difficult to apply. That is, a PSS / SSS with a period of 5 ms defined in the existing Rel-11 or lower system and a CRS-based cell search or measurement method transmitted through all downlink subframes or a periodic DRS opportunity newly defined in Rel-12 In the case of a DRS occasion based cell search or measurement method, it is possible to guarantee reception of CRS or DRS for cell search or measurement according to measurement configuration information through a corresponding RRC signal, , The frequency band can not be exclusively used, and thus it is impossible to guarantee a fixed frame structure for fixed CRS transmission or a periodical DRS opportunity by the DMTC.

Accordingly, the present invention proposes a procedure for searching or measuring a license-exempted band cell dynamically based on a control signal of a primary cell configured through a license band as a method for solving the above-mentioned problem.

4 is a diagram illustrating a signal flow according to an embodiment of the present invention.

In the case of the license-exempt band cell, it is necessary to dynamically instruct the terminal supporting the connection to the license-exempted band cell to perform cell search or measurement based on the reference signal at a time when the reference signal transmission is possible. Accordingly, the present invention provides a dynamic measurement configuration method through a control channel as a license-exiting band cell search or measurement method, and a dynamic reference signal transmission method therefor.

Referring to FIG. 4, the terminal 401 of the present invention receives measurement configuration information for searching or measuring the license-exempted bandwidth cell 409 from the base station 402 (S410). The measurement configuration information identifies the reference signal transmitted through the license-exempt band cell 409 and includes information necessary for measuring the channel condition based on the reference signal.

The terminal 401 receives the reference signal through the license-exempt band cell (S420). For example, the terminal 401 can receive the reference signal using the reference signal reception timing information included in the measurement configuration information.

The terminal 401 searches for a cell provided through the license-exempt band using the received reference signal and measurement configuration information, and measures the channel state (S430). For example, the channel state can be performed through RSRP or RSRQ measurements using a reference signal.

The terminal 401 transmits the channel measurement result including the measured channel state result information to the base station 402 (S440). The base station receives the information on the channel status of the license-exempt band cell 409 using the received channel measurement result, and determines whether the frequency band of the license-exempt band cell 409 is occupied or used by another communication system or another mobile communication carrier . The base station 402 determines whether to configure the license-exempted band cell 409 as a secondary cell of the terminal 401 or whether to activate the configured license-exempted band cell 409 and determines whether to use the license-exempted band cell 409 .

Through this, the UE can normally receive the reference signal at an aperiodic time point by acquiring information related to the reception timing and reception of the reference signal transmitted by the license-exempt band cell through the RRC-connected base station. Also, the base station can determine the merging of carriers or data transmission / reception using the corresponding license-exempt band cell to the terminal using the channel state information of the license-exempt band cell measured by the terminal. Therefore, it is possible to prevent interference or collision with other mobile communication carriers or other communication systems, and increase the data transmission rate by using the license-exempt band cell.

Hereinafter, each embodiment of the present invention will be specifically described with reference to the drawings.

1st Example . PDCCH CSS To Configure Dynamic Reference Signal Measurements Through

5 is a view for explaining a terminal operation according to another embodiment of the present invention.

A method for measuring a channel of a terminal of the present invention, the method comprising: receiving measurement configuration information for cell search and measurement from a base station; receiving a reference signal transmitted from the cell based on measurement configuration information; And measuring the cell search or channel state using the reference signal. Here, a cell refers to a cell that uses the frequency of an unlicensed band shared by one or more communication systems.

Referring to FIG. 5, the terminal of the present invention receives measurement configuration information from a base station (S510). The measurement configuration information includes information necessary for the terminal to search for and measure the license-exempt band cell. In one example, the measurement configuration information includes configuration information for measuring a reference signal transmitted in each of one or more cells using an exemption band frequency. Specifically, the measurement configuration information may include at least one of physical cell identifier information of each of one or more cells, carrier frequency information, bandwidth information for measurement, subframe-related information in which a reference signal is received, and type information of a reference signal have.

Also, the measurement configuration information may be received through the control channel common search space of the primary cell. That is, the BS may transmit information necessary for searching or measuring the license-exempted bandwidth cell through the primary cell of the MS, in the measurement configuration information. In this case, the measurement configuration information is transmitted on the control channel, and can be allocated and transmitted to the common search space.

The terminal includes receiving a reference signal transmitted from the cell based on the measurement configuration information (S520). That is, the terminal can receive the reference signal transmitted by the license-exempt band cell using the measurement configuration information received from the base station. Specifically, the reference signal can be received by using the information on the starting point at which the reference signal included in the measurement configuration information is transmitted. Alternatively, the reference signal may be received using information on the length of consecutive sub-frames in which the reference signal included in the measurement configuration information is transmitted. Alternatively, the reference signal may be received using information on the type of signal constituting the reference signal. The specific operation in which the UE receives the reference signal using the measurement configuration information will be described in detail below.

The UE includes a step of measuring a cell search or a channel state using measurement configuration information and a reference signal (S530). The terminal can search the channel of the license-exempt band cell and measure the channel state using the received measurement configuration information and the reference signal received through the license-exempt band. For example, a conventional RSRP or RSRQ measurement method can be used for channel measurement.

Hereinafter, this will be described in detail, for example.

As described above, in the case of a UE supporting a cell configured through a license band and a cell configured through a license-exempt band through a carrier merging, the reference of the license-exempted band cell through the control channel common search space of the primary cell configured through the license band Signal measurement configuration information.

For example, the reference signal measurement configuration information signaled through the primary cell's control channel (e.g., the PDCCH) common search space may include reference signal measurement configuration information of one or more license-exempt band cells. The measurement configuration information includes at least one of a physical cell identifier (PCID) of each license-exempt band cell, carrier frequency-related information in which the license-exempt band cell is configured, measurement bandwidth-related information, a relative subframe offset value at which reference signal transmission starts, The length of the reference signal occasion, and the like. Here, the relative sub-frame offset value at which the reference signal transmission starts is a relative sub-frame offset value based on the downlink sub-frame of the primary cell to which the measurement configuration information is transmitted. In addition, the length of the reference signal opportunity means a corresponding N value when a reference signal is transmitted through N consecutive subframes.

In addition, the measurement configuration information includes information for indicating a type of a signal constituting the reference signal or a signal constituting the reference signal when a CSI-RS is used, a scrambling ID (scrambling ID ), CSI-RS RE configuration information, cover code information, and the like. For example, the reference signal may be composed of PSS / SSS and CRS, or may be composed of PSS / SSS, CRS and CSI-RS. Or the reference signal may be configured as a combination of other types of downlink reference signals.

6 is a diagram for explaining a terminal operation according to another embodiment of the present invention.

Referring to FIG. 6, a UE according to another exemplary embodiment of the present invention may receive measurement configuration information including one or more reference signal format information through higher layer signaling (S610). The UE may store the received measurement configuration information, and may then indicate some of the reference signal format information included in the measurement configuration information or receive indication information indicating a reference signal transmission (S620). The indication information may be received through the control channel common search space of the primary cell described above. Or the indication information may be received through the control channel terminal specific search space of the primary cell described above.

Specifically, a physical cell identifier (PCID) for each license-exempt band cell, carrier frequency-related information composed of the license-exempt band cell, measurement bandwidth-related information, information indicating the type of signal constituting the reference signal, RS, a scrambling ID for generating a corresponding CSI-RS, a CSI-RS RE configuration information, and a cover code information, The reference signal format transmitted from the license-exempted band cell can be preset and transmitted to the terminal through higher layer signaling (for example, RRC signaling). Thereafter, only the dynamic (or non-periodic) reference signal transmission indication information indicating the reference signal transmission in each of the license-exempt band cells through the primary cell control channel common search space is transmitted through the corresponding control channel common search space . That is, the dynamic (or non-periodic) reference signal format for each license-exempted band cell is informed to the terminal in advance as measurement configuration information through higher-layer signaling, and when the corresponding reference signal is transmitted in an unlicensed band cell, Information such as a physical cell identifier (PCID) of a license-exempt band cell in which a reference signal is transmitted using the configuration information, a related sub-frame offset value, and a length of a reference signal opportunity may be transmitted to the terminal through the corresponding indication information.

Then, the UE can receive the reference signal using the measurement configuration information and the instruction information (S630). Also, as described in step S530, the license-exempt band cell can be searched and the channel state can be measured (S640).

On the other hand, the measurement configuration signal for the reference signal through the control channel common search space or the indication information for the reference signal may include only some of the information described above. For example, in generating the measurement configuration information, the relative sub-frame offset value at which the reference signal transmission starts, the length of the reference signal opportunity, and the like may be defined to have any fixed value instead of being included in the measurement configuration information. It is also possible to transmit the reference signal through all N subframes corresponding to the length of the reference signal opportunity or to transmit the reference signal through some of the subframes.

A new RNTI value may be defined as an RNTI dedicated to the measurement configuration information or an indication information dedicated RNTI for the reference signal for defining the reference signal measurement configuration information or the indication information through the control channel common search space. The UE can define blind decoding of measurement configuration information or indication information based on the RNTI.

Second Example . Transmit measurement configuration information through the UE-specific search space of the control channel

A UE according to another embodiment of the present invention can receive measurement configuration information through a control channel of a primary cell. In particular, the measurement configuration information may be received through the UE specific search space of the control channel.

For example, it may be defined to receive the measurement configuration information of the license-exempt band cell through the PDCCH of the primary band of the license band or the UE-specific Search Space of the EPDCCH. At this time, the measurement configuration information signaled through the control channel USS of the primary cell may include measurement configuration information of one or more license-exempt band cells. In one example, the measurement configuration information includes a physical cell identifier (PCID) of each license-exempt band cell, carrier frequency-related information comprising the license-exempt band cell, measurement band-width-related information, And length information of the signal opportunity. In addition, information indicating the type of a signal constituting the reference signal, a scrambling ID for generating a corresponding CSI-RS when the CSI-RS is used as a signal constituting the reference signal, CSI-RS resource element configuration information, Cover code information, and the like. In this case, the DCI format for transmitting the measurement configuration information is newly defined, and the UE-specific measurement configuration information can be transmitted by scrambling and transmitting the UE-specific measurement configuration information to the C-RNTI of the corresponding UE.

As another method, as described in the first embodiment, the measurement configuration information includes a physical cell identifier (PCID) for each license-exempt band cell, carrier frequency-related information composed of the license-exempt band cell, measurement band width-related information, A scrambling ID for generating a corresponding CSI-RS when the CSI-RS is used as a signal constituting the reference signal, a CSI-RS resource element configuration information, a cover code Information of at least one of information in the unlicensed band cell, and transmits the reference signal format to the terminal in advance through higher layer signaling. Then, when transmitting a reference signal in each of the license-exempt band cells through the control channel USS of the primary cell, only the indication information indicating the reference signal can be transmitted through the corresponding control channel USS. In other words, the reference signal format for each unlicensed band cell is included in the measurement configuration information and is transmitted to the terminal in advance in the upper layer signaling, and when the reference signal is actually transmitted in the license-exempt band cell, At least one of a physical cell identifier of a band cell, a relative sub-frame offset value at which transmission of a reference signal starts, and a length of a reference signal opportunity can be transmitted to the terminal via the indication information. The UE can receive the reference signal by checking the reference signal format of the cell having the corresponding physical cell identifier in the previously stored measurement configuration information using the received indication information.

Meanwhile, a separate DCI format for transmitting the instruction information may be newly defined, scrambled and transmitted in the C-RNTI of the corresponding terminal, or the corresponding information region may be additionally defined in the existing DL assignment DCI format or UL grant DCI format You may. Alternatively, in the case of the corresponding direction information, a bitmap indication bit is assigned for each carrier frequency of the license-exempt DCM format or UL grant DCI format, And may be defined to indicate whether the reference signal transmission is performed in the license-exempt band cell configured through the corresponding band. In this case, the relative sub-frame offset value at which the reference signal transmission starts, the length of the reference signal opportunity, etc. may have any fixed value as in the first embodiment described above or may be set quasi-statically through higher layer signaling .

The base station capable of performing the operations of the present invention described above will be described with reference to the drawings.

7 is a view for explaining a base station operation according to another embodiment of the present invention.

A method of controlling a channel measurement of a terminal according to another embodiment of the present invention includes the steps of generating measurement configuration information for cell search and measurement, transmitting measurement configuration information, And receiving measured channel state measurement information from the terminal based on the transmitted reference signal. A cell also refers to a cell using an unlicensed band frequency shared by one or more communication systems.

Referring to FIG. 7, the base station of the present invention includes a step of generating measurement configuration information for cell search and measurement (S710). The measurement configuration information may include configuration information for measuring a reference signal transmitted in each of the one or more cells using the license-exempt band frequency. For example, the measurement configuration information may include at least one of physical cell identifier information of each of one or more cells, carrier frequency information, bandwidth information for measurement, subframe-related information in which a reference signal is received, and type information of a reference signal . In addition, the measurement configuration information may include various kinds of information described in each of the above embodiments.

The base station includes transmitting measurement configuration information (S720). For example, the BS may transmit the measurement configuration information through the control channel of the primary cell configured in the MS. Or the base station may transmit measurement configuration information via higher layer signaling.

Specifically, the base station can transmit the measurement configuration information through the common search space of the control channel as in the first embodiment. Alternatively, the base station may transmit the measurement configuration information through the UE-specific search space of the PDCCH or EPDCCH as in the second embodiment. In this case, the BS scrambles using the C-RNTI of the UE to transmit UE measurement configuration information.

The base station includes receiving the measured channel state measurement information from the UE based on the measurement configuration information and the reference signal transmitted from the cell (S730).

8 is a view for explaining a base station operation according to another embodiment of the present invention.

A base station according to another embodiment of the present invention can transmit measurement configuration information through upper layer signaling. In this case, the measurement configuration information includes reference signal format information of each of the one or more license-exempt band cells. The terminal stores the received reference signal format information and receives the reference signal using the reference signal format information for the license-exempted band cell when the instruction information for instructing the reference signal transmission of the specific license-exempt band cell is received from the base station have. The indication information may further include information (for example, a related sub-frame offset value, reference signal opportunity length information, and the like) for the reception timing of the reference signal.

Referring to FIG. 8, the base station includes a step of generating measurement configuration information for reference signal search and measurement of a license-exempt band cell (S810). As described above, the measurement configuration information includes a physical cell identifier (PCID) for each license-exempt band cell, carrier frequency-related information composed of the license-exempt band cell, measurement band width-related information, information indicating the type of signal constituting the reference signal , A reference including at least one of a scrambling ID for generating a corresponding CSI-RS, a CSI-RS resource element configuration information, and a cover code information when the CSI-RS is used as a signal constituting the reference signal And signal format information.

The base station transmits the generated measurement configuration information to the terminal through higher layer signaling (S820). For example, the base station may transmit measurement configuration information through higher-layer signaling through a primary cell that has established an RRC connection to the terminal.

Thereafter, the base station may transmit the indication information when the reference signal is transmitted in the license-exempt band cell (S830). The indication information may include information indicating that the reference signal is to be transmitted. In addition, the instruction information may include information indicating the specific reference signal format of the measurement configuration information or information related to the reception time of the reference signal, as described above.

The base station can receive channel state measurement information from the terminal (S840). The channel state measurement information may include state information on the channel measured using the reference signal of the license-exempted band cell received by the terminal using the measurement configuration information and the instruction information. Through this, the base station can determine whether to add a secondary cell of the license-exempt band cell or activate the license-exempt band cell added to the secondary cell.

As described above, the present invention provides an effect of preventing signal interference and transmitting a large amount of data at a high speed when different wireless communication systems transmit and receive data using the same frequency band. In addition, the present invention provides an effect of preventing ambiguity of a terminal when carrier merging is performed using a license-exempt band frequency.

Hereinafter, a configuration of a terminal and a base station to which all of the embodiments of the present invention can be practiced will be described again.

9 is a diagram illustrating a terminal configuration according to another embodiment of the present invention.

9, a user terminal 900 according to another embodiment of the present invention includes a receiver 930, a controller 910, and a transmitter 920.

The terminal 900 of the present invention includes a receiving unit 930 that receives measurement configuration information for cell search and measurement from a base station and receives a reference signal transmitted from the cell based on measurement configuration information, And a controller 910 for measuring a cell search or a channel state using the received signal. Here, a cell refers to a cell that uses the frequency of an unlicensed band shared by one or more communication systems.

The receiver 930 receives downlink control information, data, messages, and measurement configuration information from the base station. As an example, the measurement configuration information may be received through the control channel common search space of the primary cell. As another example, the measurement configuration information may be received through the control channel terminal specific search space of the primary cell. As another example, measurement configuration information may be received via higher layer signaling.

The receiving unit 930 can further receive the receiving timing of the reference signal of the license-exempt band cell or the instruction information indicating the reference signal format included in the measurement configuration information.

The control unit 910 controls the overall operation of the terminal for receiving the measurement configuration information or the indication information necessary for performing the above-described present invention, and in measuring the channel status using the reference signal of the license- And controls the operation.

In addition, the controller 910 controls the overall operation of the terminal according to the terminal operation of the present invention described with reference to FIGS.

The transmitter 920 transmits uplink control information, data, and a message to the base station through a corresponding channel, and transmits a channel state measurement result.

10 is a diagram illustrating a base station configuration according to another embodiment of the present invention.

10, a base station 1000 according to another embodiment includes a control unit 1010, a transmission unit 1020, and a reception unit 1030.

A base station according to another exemplary embodiment of the present invention includes a controller 1010 for generating measurement configuration information for cell search and measurement, a transmitter 1020 for transmitting measurement configuration information, And a reception unit 1030 that receives measured channel state measurement information from a terminal. A cell is a cell that uses an unlicensed band frequency shared by one or more communication systems.

The control unit 1010 generates measurement configuration information. For example, the measurement configuration information includes information necessary for a terminal to receive a reference signal transmitted in a license-exempt band cell.

In addition, the control unit 1010 carries out merging of the licensed band and the license-exempted cell, which are necessary for carrying out the present invention, to the terminal, and controls the overall operation of the base station in order to generate and transmit measurement configuration information can do.

The transmitting unit 1020 transmits measurement configuration information. In one example, the measurement configuration information may be transmitted through the control channel common search space of the primary cell. As another example, the measurement configuration information may be transmitted through the control channel terminal specific search space of the primary cell. As another example, measurement configuration information may be transmitted via higher layer signaling.

The transmitting unit 1020 may further transmit indication information indicating a reference signal reception timing of the license-exempt band cell or a reference signal format included in the measurement configuration information.

The receiving unit 1030 can receive channel state measurement result information transmitted from the UE.

In addition, the transmitting unit 1020 and the receiving unit 1030 are used for transmitting / receiving signals, messages, and data necessary for performing the above-described present invention to / from the terminal.

The standard content or standard documents referred to in the above-mentioned embodiments constitute a part of this specification, for the sake of simplicity of description of the specification. Therefore, it is to be understood that the content of the above standard content and portions of the standard documents are added to or contained in the scope of the present invention.

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.

Claims (20)

A method for a terminal to measure a channel,
Receiving measurement configuration information for cell search and measurement from a base station;
Receiving a reference signal transmitted in the cell based on the measurement configuration information; And
Measuring the cell search or channel state using the measurement configuration information and the reference signal,
Wherein the cell is a cell using a frequency of an unlicensed band shared by one or more communication systems. The method according to claim 1,
Wherein the measurement configuration information comprises:
The control channel common search space of the primary cell. The method according to claim 1,
Wherein the measurement configuration information comprises:
Wherein the control channel is received through a control channel terminal specific search space of the primary cell. The method according to claim 1,
The measurement configuration information including one or more reference signal format information is received via higher layer signaling,
Further comprising receiving instruction information indicating at least one of the reference signal format information,
Wherein the indication information is received in a control channel terminal common search space of a primary cell or a control channel terminal specific search space of the primary cell. The method according to claim 1,
Wherein the measurement configuration information comprises:
And configuration information for measuring a reference signal transmitted in each of the one or more cells using the license-exempt band frequency,
Wherein the at least one cell comprises at least one of physical cell identifier information, carrier frequency information, bandwidth information for measurement, subframe-related information in which the reference signal is received, and type information of the reference signal. A method for a base station to control channel measurement of a terminal,
Generating measurement configuration information for cell search and measurement;
Transmitting the measurement configuration information; And
And receiving from the terminal channel measurement information measured based on the measurement configuration information and the reference signal transmitted from the cell,
Wherein the cell is a cell using an unlicensed band frequency shared by one or more communication systems. The method according to claim 6,
Wherein the measurement configuration information comprises:
And the control channel is transmitted through the common search space of the control channel. The method according to claim 6,
Wherein the transmitting the measurement configuration information comprises:
Wherein the downlink control information format defined for transmission of the measurement configuration information is scrambled with a Cell-Radio Network Temporary Identifier (C-RNTI) of the UE. The method according to claim 6,
Wherein the transmitting the measurement configuration information comprises:
Transmitting the measurement configuration information including one or more reference signal format information through higher layer signaling,
And transmitting indication information indicating at least one of the reference signal format information,
Wherein the indication information is transmitted in a control channel terminal common search space of a primary cell or a control channel terminal specific search space of the primary cell. The method according to claim 6,
Wherein the measurement configuration information comprises:
And configuration information for measuring a reference signal transmitted in each of the one or more cells using the license-exempt band frequency,
Wherein the at least one cell comprises at least one of physical cell identifier information, carrier frequency information, bandwidth information for measurement, subframe-related information in which the reference signal is received, and type information of the reference signal. A terminal for measuring a channel,
A receiving unit receiving measurement configuration information for cell search and measurement from a base station and receiving a reference signal transmitted from the cell based on the measurement configuration information; And
And a controller for measuring the cell search or channel state using the measurement configuration information and the reference signal,
Wherein the cell is a cell using a frequency of an unlicensed band shared by one or more communication systems. 12. The method of claim 11,
Wherein the measurement configuration information comprises:
And a control channel common search space of a primary cell. 12. The method of claim 11,
Wherein the measurement configuration information comprises:
And the control channel is received through a control channel terminal specific search space of a primary cell. 12. The method of claim 11,
The receiver may further comprise:
Receiving the measurement configuration information including one or more reference signal format information through higher layer signaling,
Further receiving instruction information indicating at least one of the reference signal format information,
Wherein the indication information is received in a control channel terminal common search space of a primary cell or a control channel terminal specific search space of the primary cell. 12. The method of claim 11,
Wherein the measurement configuration information comprises:
And configuration information for measuring a reference signal transmitted in each of the one or more cells using the license-exempt band frequency,
Wherein the at least one cell includes at least one of physical cell identifier information, carrier frequency information, bandwidth information for measurement, subframe related information at which the reference signal is received, and type information of the reference signal. A base station for controlling channel measurement of a terminal,
A controller for generating measurement configuration information for cell search and measurement;
A transmitter configured to transmit the measurement configuration information; And
And a receiving unit for receiving the measurement configuration information and channel state measurement information measured based on the reference signal transmitted from the cell, from the terminal,
Wherein the cell is a cell using an unlicensed band frequency shared by one or more communication systems. 17. The method of claim 16,
Wherein the measurement configuration information comprises:
Wherein the control channel is transmitted through a common search space of the control channel. 17. The method of claim 16,
The transmitter may further comprise:
Wherein the base station scrambles the downlink control information format defined for transmission of the measurement configuration information to a Cell-Radio Network Temporary Identifier (C-RNTI) of the UE, and transmits the scrambled downlink control information format. 17. The method of claim 16,
The transmitter may further comprise:
Transmitting the measurement configuration information including one or more reference signal format information through higher layer signaling,
Further transmitting indication information indicating at least one of the reference signal format information,
Wherein the indication information is transmitted in a control channel terminal common search space of a primary cell or a control channel terminal specific search space of the primary cell. 17. The method of claim 16,
Wherein the measurement configuration information comprises:
And configuration information for measuring a reference signal transmitted in each of the one or more cells using the license-exempt band frequency,
Wherein the at least one cell includes at least one of physical cell identifier information, carrier frequency information, bandwidth information for measurement, subframe-related information in which the reference signal is received, and type information of the reference signal.

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