KR20140080280A - Method and apparatus of drx reconfiguration considering nct in mulitple component carrier sysyem - Google Patents

Abstract

The present invention relates to a method and an apparatus for discontinuous reception (DRX) reconfiguration in consideration of a new carrier type (NCT) in a multiple component carrier system. The method comprises the steps of: receiving a radio resource control (RRC) connection reconfiguration message including NCT secondary serving cell configuration information and reduced CRC information from a base station; configuring the NCT secondary serving cell based on the NCT secondary serving cell configuration information; generating an RRC connection reconfiguration completion message indicating that a user equipment (UE) has completed RRC connection reconfiguration based on the RRC connection reconfiguration message; transmitting the generated RRC connection reconfiguration completion message to the base station; and performing DRX reconfiguration in the UE based on DRX related parameters provided in the UE and the reduced CRS information. According to the present invention, when the NCT secondary serving cell is configured in the UE, the UE can implicitly conduct the DRX reconfiguration in consideration of the reduced CRS information, which is periodically transmitted, to measure a channel state on the NCT secondary serving cell, based on information on the reduced CRS. As a result, the accuracy of the channel state measurement can be guaranteed.

Description

METHOD AND APPARATUS OF DRX RECONFIGURATION CONSIDERING NCT IN MULTIPLE COMPONENT CARRIER SYSYEM USING THE NCT IN A MULTI-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wireless communication, and more particularly, to a method and apparatus for DRX (Discontinuous Reception) reconfiguration considering a NCT (New Carrier Type) in a multi-element carrier system.

In a typical wireless communication system, although a bandwidth between an uplink and a downlink is set to be different from each other, only one carrier is mainly considered. In the 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution), the number of carriers constituting the uplink and the downlink is 1 based on a single carrier, and the bandwidths of the UL and the DL are generally symmetrical to be. In this single carrier system, random access performs wireless communication using one carrier. However, recently, as a multiple carrier system has been introduced, wireless communication can be implemented through a plurality of component carriers.

A multi-element carrier system refers to a wireless communication system capable of supporting carrier aggregation (CA). Carrier aggregation is a technique for efficiently using fragmented small bands. It has the same effect as using a logically large bands by bundling a plurality of physically continuous or non-continuous bands in the frequency domain. In order to make it possible.

However, the component carrier (CC) used in the existing LTE system emphasizes the general purpose of the physical layer, and there is still a control area overlap and a common signal overhead, so that the data area to be transmitted is reduced and spectral efficiency and there is an unnecessary loss in terms of efficiency. Accordingly, the introduction of a new carrier type (NCT) constituting a multi-carrier system has been under discussion in order to efficiently operate the multi-carrier system. In the NCT, signaling for control signaling or channel estimation can be eliminated or reduced within a range where performance is not deteriorated or minimized as compared with the legacy carrier type. Thus, the maximum data transmission efficiency can be obtained.

The NCT cell may be included as a secondary serving cell (Scell) when the primary serving cell (Pcell) is a legacy carrier type at the time of carrier aggregation. At this time, the cell of the NCT can not exist in a single cell form and can be a non-stand alone cell existing as a secondary serving cell only when the main serving cell exists. On the other hand, the cell of the NCT can be used not only as a secondary serving cell but also as a main serving cell. At this time, the cell of the NCT may be a stand alone cell which may exist in a single cell form.

On the other hand, in a wireless communication system, packet data traffic is often bursty, such as when a lot of transmission activity occurs during a transient period of time and there is no transmission for a long time or a sudden large amount of traffic occurs. From the viewpoint of delay, it is preferable to observe the downlink control signaling every subframe in order to receive the uplink scheduling grant or the downlink data transmission and react immediately according to the change of the traffic operation. However, since power consumption by a receiving circuit of a general terminal is also an amount of consumption that can not be ignored, continuous operation of the receiving circuit increases power consumption of the terminal. In order to reduce the power consumption of the UE, the LTE system supports discontinuous reception (DRX). When the DRX scheme is used, the UE can alternately operate in non-active time and active time. Through this, the terminal can reduce power consumption.

However, unlike the existing legacy carrier type, in the NCT, since transmission of a reference signal (RE) for channel estimation such as a CRS (Cell-specific Reference Signal) can be performed more rarely, , The UE may not smoothly perform the downlink channel estimation. That is, when the UE is connected to the cell of the NCT, unlike the case where the UE is connected to a cell of a legacy carrier type used in the past, a problem may arise in the measurement accuracy according to the DRX setting, This may cause problems such as wireless communication failure between the terminal and the base station in some cases. Therefore, it is required to construct or reconfigure the DRX considering the NCT in the terminal and the base station.

SUMMARY OF THE INVENTION The present invention provides a DRX reconstruction method and apparatus considering a NCT in a multi-element carrier system.

It is another object of the present invention to provide a method and apparatus for providing reduced CRS information of a NCT to a terminal.

Another technical problem of the present invention is to perform DRX reconstruction considering the reduced CRS information in the NCT.

Another technical problem of the present invention is to perform DRX reconstruction considering the reduced CRS period in the NCT.

Another aspect of the present invention is to implicitly perform DRX reconfiguration by an agreement between a terminal and a base station.

Another aspect of the present invention is to provide a method and apparatus for performing DRX reconfiguration between a terminal and a base station when a secondary serving cell of an NCT is added to the terminal.

According to an aspect of the present invention, there is provided a UE performing a DRX (Discontinuous Reception) operation considering a NCT (New Carrier Type) in a Multiple Complement Carrier System. The UE includes a receiver for receiving a Radio Resource Control (RRC) connection reconfiguration message including NCT secondary serving cell configuration information and reduced CRS information from a base station (eNB), an NCT secondary serving cell configuration information A message processor for configuring the NCT secondary serving cell based on the RRC connection reconfiguration completion message and generating an RRC connection reconfiguration complete message, a transmitter for transmitting the generated RRC connection reconfiguration complete message to the base station, And a DRX operation controller for performing DRX reconfiguration at the UE based on the reduced CRS information.

According to another aspect of the present invention, there is provided a base station for performing a DRX operation considering NCT in a multi-element carrier system, comprising: a message processor for generating an RRC connection reconfiguration message including NCT secondary serving cell configuration information and reduced CRS information; Based on the DRX-related parameters and the reduced CRS information currently configured for the UE, a DRX connection reconfiguration message for the RRC connection reconfiguration message to the UE, And a DRX operation control unit for performing reconfiguration.

According to another aspect of the present invention, there is provided a DRX reconstruction method considering a NCT performed by a UE in a multi-element carrier system. The method includes receiving an RRC connection reconfiguration message including a NCT secondary serving cell configuration information and a reduced CRS information from a base station, configuring the NCT secondary serving cell based on the NCT secondary serving cell configuration information, Generating an RRC connection reconfiguration completion message indicating that the UE has completed RRC connection reconfiguration based on the reconfiguration message, transmitting the generated RRC connection reconfiguration complete message to the base station, And performing DRX reconstruction at the terminal based on the reduced CRS information and the reduced CRS information.

According to another aspect of the present invention, there is provided a DRX reconstruction method considering a NCT performed by a base station in a multi-element carrier system. The method includes: generating an RRC connection reconfiguration message including NCT secondary serving cell configuration information and reduced CRS information; transmitting the generated RRC connection reconfiguration message to a terminal; receiving an RRC connection reconfiguration completion message from the terminal; And DRX reconfiguration at the base station based on the DRX-related parameters and the reduced CRS information currently configured for the UE.

According to the present invention, when the NCT sub-serving cell is configured in the UE, the UE calculates DRX reconstruction considering the reduced CRS transmitted periodically for channel state measurement on the NCT secondary serving cell based on the information on the reduced CRS Can be performed. This ensures the accuracy of channel state measurement.

Also, according to the present invention, the UE and the BS can implicitly perform DRX reconfiguration when a specific situation occurs, so that the BS does not have to transmit an RRC connection reconfiguration message to the UE, and can reduce network traffic burden.

1 shows a wireless communication system to which the present invention is applied.
FIG. 2 shows an example of a protocol structure for supporting a multi-element carrier wave to which the present invention is applied.
FIG. 3 shows an example of a frame structure for a multi-component carrier wave operation to which the present invention is applied.
FIG. 4 illustrates a linkage between a downlink component carrier and an uplink component carrier in a multi-component carrier system to which the present invention is applied.
FIG. 5 shows a structure of a subframe of a physical layer used in a wireless communication system to which the present invention is applied.
6 is a conceptual diagram showing a DRX operation applied to the present invention.
7 shows an example of a CRS transmission in a DL sub-frame and a DRX operation of a UE in case of a legacy carrier type.
FIG. 8 shows an example of a reduced CRS transmission and a DRX operation of a UE in a downlink subframe in the case of an NCT.
FIG. 9 shows an example of a CRS transmission and a DRX operation of a terminal when a terminal uses a legacy carrier type and an NCT simultaneously in a multi-carrier system.
10 illustrates a DRX operation considering an NCT in a multi-carrier system according to an exemplary embodiment of the present invention.
11 illustrates a DRX operation considering an NCT in a multi-carrier system according to another example of the present invention.
FIG. 12 shows reduced CRS information transmission through a broadcast control channel (BCCH) according to an exemplary embodiment of the present invention.
FIG. 13 shows reduced CRS information transmission over a dedicated control channel (DCCH) according to another example of the present invention.
FIG. 14 shows a configuration of an NCT secondary serving cell and DRX reconstruction according to an exemplary embodiment of the present invention.
15 shows a configuration of an NCT secondary serving cell and a DRX reconstruction according to another example of the present invention.
16 shows a structure of a MAC message to which the present invention is applied.
17 is a block diagram illustrating the structure of a MAC control element according to an exemplary embodiment of the present invention. This represents the MAC control element for activation / deactivation.
18 shows an example of a MAC control element for instructing activation of an NCT secondary serving cell according to an example of the present invention.
FIG. 19 shows a DRX reconstruction method considering an NCT performed in a terminal according to an exemplary embodiment of the present invention.
20 shows a DRX reconstruction method considering NCT performed in a base station according to an example of the present invention.
FIG. 21 is a block diagram illustrating a terminal and a base station performing DRX reconfiguration considering an NCT according to an exemplary embodiment of the present invention. Referring to FIG.

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 symbols as 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 configurations or functions will be omitted if it is determined that the gist of the present specification may be obscured.

In addition, the present invention will be described with respect to a wireless communication network. The work performed in the wireless communication network may be performed in a process of controlling a network and transmitting data by a system (e.g., a base station) Work can be done at a terminal connected to the network.

1 shows a wireless communication system to which the present invention is applied.

Referring to FIG. 1, a wireless communication system 10 is widely deployed to provide various communication services such as voice, packet data, and the like. The wireless communication system 10 includes at least one base station 11 (BS). Each base station 11 provides communication services to specific cells (15a, 15b, 15c). The cell may again be divided into multiple regions (referred to as sectors).

A user equipment (UE) 12 may be fixed or mobile and may be a mobile station (MS), a mobile terminal (UT), a subscriber station (SS), a wireless device, (personal digital assistant), a wireless modem, a handheld device, and the like. The base station 11 may be called by other terms such as an evolved-NodeB (eNB), a base transceiver system (BTS), an access point, a femto base station, a home node B, . The cell should be interpreted in a generic sense to indicate a partial area covered by the base station 11 and is meant to cover various coverage areas such as a megacell, a macro cell, a microcell, a picocell, and a femtocell.

Hereinafter, downlink refers to communication from the base station 11 to the terminal 12, and uplink refers to communication from the terminal 12 to the base station 11. In the downlink, the transmitter may be part of the base station 11, and the receiver may be part of the terminal 12. In the uplink, the transmitter may be part of the terminal 12, and the receiver may be part of the base station 11. There are no restrictions on multiple access schemes applied to wireless communication systems. (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier-FDMA , OFDM-CDMA, and the like. 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.

A Carrier Aggregation (CA) supports a plurality of carriers and is also referred to as spectrum aggregation or bandwidth aggregation. Carrier aggregation is a technique for efficiently using a fragmented small band. It is a technique in which a plurality of physically continuous or non-continuous bands in the frequency domain are combined to use a logically large band, . An individual unit carrier tied by carrier aggregation is referred to as a component carrier (CC). Each element carrier is defined as the bandwidth and center frequency. Carrier aggregation is introduced to support increased throughput, prevent cost increase due to the introduction of wideband radio frequency (RF) devices, and ensure compatibility with existing systems. For example, if five elementary carriers are allocated as the granularity of a carrier unit having a bandwidth of 20 MHz, it can support a bandwidth of up to 100 MHz.

Carrier aggregation can be divided into contiguous carrier aggregation between successive element carriers in the frequency domain and non-contiguous carrier aggregation between discontinuous element carriers. The number of carriers aggregated between the downlink and the uplink may be set differently. The case where the number of downlink element carriers is equal to the number of uplink element carriers is referred to as symmetric aggregation and the case where the number of downlink element carriers is different is referred to as asymmetric aggregation.

The size (i.e. bandwidth) of the element carriers may be different. For example, if five element carriers are used for a 70 MHz band configuration, then 5 MHz element carrier (carrier # 0) + 20 MHz element carrier (carrier # 1) + 20 MHz element carrier (carrier # 2) + 20 MHz element carrier (carrier # 3) + 5 MHz element carrier (carrier # 4).

Hereinafter, a multiple component carrier system refers to a system including a terminal supporting a carrier aggregation and a base station. In a multi-element carrier system, adjacent carrier aggregation and / or non-adjacent carrier aggregation may be used, and either symmetric aggregation or asymmetric aggregation may be used.

FIG. 2 shows an example of a protocol structure for supporting a multi-element carrier wave to which the present invention is applied.

Referring to FIG. 2, a common medium access control (MAC) entity 210 manages a physical layer 220 using a plurality of carriers. The MAC management message transmitted on a specific carrier may be applied to other carriers. That is, the MAC management message is a message capable of controlling other carriers including the specific carrier. The physical layer 220 may operate as a time division duplex (TDD) and / or a frequency division duplex (FDD).

There are some physical channels used in the physical layer 220.

First, as a downlink physical channel, a physical downlink control channel (PDCCH) transmits a paging channel (PCH), a resource allocation of a downlink shared channel (DL-SCH), and Hybrid Automatic Repeat Request (HARQ) It informs. The PDCCH may carry an uplink grant informing the UE of the resource allocation of the uplink transmission. A DL-SCH is mapped to a physical downlink shared channel (PDSCH). The Physical Control Format Indicator Channel (PCFICH) informs the UE of the number of OFDM symbols used for PDCCHs and is transmitted every subframe. The Physical Hybrid ARQ Indicator Channel (PHICH) is a downlink channel, and carries an HARQ ACK / NACK signal which is a response of an uplink transmission.

Next, as an uplink physical channel, a Physical Uplink Control Channel (PUCCH) carries uplink control information such as a HARQ ACK / NACK signal for downlink transmission, a scheduling request, and a CQI. The Physical Uplink Shared Channel (PUSCH) carries an Uplink Shared Channel (UL-SCH). A Physical Random Access Channel (PRACH) carries a random access preamble.

FIG. 3 shows an example of a frame structure for a multi-component carrier wave operation to which the present invention is applied.

Referring to FIG. 3, one frame is composed of 10 subframes. The subframe may be composed of a plurality of OFDM symbols on the time axis and at least one element carrier in the frequency axis. Each element carrier may have its own control channel (e.g., PDCCH). The multi-element carriers may or may not be adjacent to each other. The terminal may support one or more element carriers according to its capabilities.

The element carrier may be divided into a primary component carrier (PCC) and a secondary component carrier (SCC). The terminal may use only one major carrier or use one or more sub-carrier with carrier. A terminal may be allocated a primary carrier and / or secondary carrier from a base station. The element carrier may be represented by a cell or a serving cell. An element carrier not explicitly expressed as a downlink CC or an uplink CC may be configured to include both a downlink component carrier and an uplink component carrier or may include only a downlink component carrier, .

FIG. 4 illustrates a linkage between a downlink component carrier and an uplink component carrier in a multi-component carrier system to which the present invention is applied.

Referring to FIG. 4, the downlink component carriers D1, D2, and D3 are aggregated in the downlink, and the uplink component carriers U1, U2, and U3 are aggregated in the uplink. Where Di is the index of the downlink component carrier and Ui is the index of the uplink component carrier (i = 1, 2, 3). At least one downlink element carrier is a dominant carrier and the remainder is a subordinate element carrier. Similarly, at least one uplink component carrier is a dominant carrier and the remainder is a subindent carrier. For example, D1, U1 are the dominant carriers, and D2, U2, D3, U3 are the subelement carriers. Where the index of the dominant carrier may be set to zero and one of the other natural numbers may be the index of the subindent carrier. The index of the downlink / uplink component carrier may be set equal to the index of an element carrier (or serving cell) including the downlink / uplink component carrier. As another example, only the elementary carrier index or the sub-element carrier index may be set and the uplink / uplink element carrier index included in the corresponding element carrier may not exist.

In the FDD system, the downlink component carrier and the uplink component carrier can be set to be 1: 1. For example, D1 may be set to U1, D2 to U2, and D3 to 1: 1. The UE establishes a connection between the downlink component carriers and the uplink component carriers through the system information transmitted by the logical channel BCCH or the terminal dedicated RRC message transmitted by the DCCH. This connection is referred to as SIB1 (system information block 1) connection or SIB2 (system information block 2) connection. Each connection setting may be cell specific or UE specific. In one example, the primary carrier may be set to cell specific and the secondary carrier may be set to be UE specific.

4 illustrates only a 1: 1 connection setup between the downlink component carrier and the uplink component carrier, but it is needless to say that a 1: n or n: 1 connection setup can also be established. The index of the element carrier does not match the order of the element carriers or the position of the frequency band of the corresponding element carrier.

A primary serving cell is a serving cell that provides security input and NAS mobility information in the RRC establishment or re-establishment state. Depending on the capabilities of the terminal, at least one cell may be configured to form a set of serving cells together with a main serving cell, said at least one cell being referred to as a secondary serving cell.

Therefore, the set of serving cells set for one UE may consist of only one main serving cell, or may consist of one main serving cell and at least one secondary serving cell.

The downlink component carrier corresponding to the main serving cell is referred to as a downlink principal carrier (DL PCC), and the uplink component carrier corresponding to the main serving cell is referred to as an uplink principal carrier (UL PCC). In the downlink, the element carrier corresponding to the secondary serving cell is referred to as a downlink sub-element carrier (DL SCC), and in the uplink, an elementary carrier corresponding to the secondary serving cell is referred to as an uplink sub-element carrier (UL SCC) do. Only one DL serving carrier may correspond to one serving cell, and DL CC and UL CC may correspond to each other.

Therefore, the communication between the terminal and the base station in the carrier system is performed through the DL CC or the UL CC, which is equivalent to the communication between the terminal and the base station through the serving cell. For example, in the method of performing random access according to the present invention, the UE transmits a preamble on the UL CC, which is equivalent to transmitting a preamble on a main serving cell or a secondary serving cell. In addition, receiving the downlink information on the DL CC by the UE can be regarded as equivalent to receiving the downlink information on the main serving cell or the secondary serving cell.

FIG. 5 shows a structure of a subframe of a physical layer used in a wireless communication system to which the present invention is applied.

Referring to FIG. 5, one radio frame includes ten subframes, and one subframe includes two consecutive slots. In the case of downlink, 1, 2, 3, or 4 OFDM symbols preceding the first slot in the subframe are control channel regions to which the PDCCH is mapped, and the remaining OFDM symbols are physical downlink shared channel: PDSCH) is mapped to a data channel region. The control channel region may be referred to as a control region, and the data channel region may be referred to as a data region. In addition to the PDCCH, a control channel such as a PCFICH or a PHICH may be allocated to the control channel region. The UE can decode the PDCCH and read the data information transmitted on the PDSCH. The number of OFDM symbols that constitute the control channel region in the subframe can be known through the PCFICH. For example, when the system bandwidth is N ^DL _RB > 10, the PCFICH indicates the first one, two or three OFDM symbols as the control channel region, and when N ^DL _{RB ≤} 10, 3, or 4 OFDM symbols into the control channel region.

The UE generates PDCCHs based on a cell-radio network temporary identifier (C-RNTI), transmission power control (PPC) -PUCCH-RNTI, TPC-PUSCH-RNTI and semi persistent scheduling (SPS) Monitoring can be performed. The monitoring of the PDCCH can be controlled by the DRX operation, and the parameter related to the DRX is transmitted to the mobile station by the RRC message. The UE must always receive SI (system information) -RNTI, P (paging) -RNTI, etc. other than the RNTIs regardless of the DRX operation configured by the RRC message. Here, the remaining PDCCHs other than the PDCCH scrambled with the C-RNTI are always received through the common search space of the main serving cell.

If the DRX parameter is configured in the RRC connected state, the UE performs discontinuous monitoring on the PDCCH based on the DRX operation. On the other hand, if the DRX parameter is not configured, the UE performs continuous PDCCH monitoring. Discontinuous PDCCH monitoring means that the UE monitors the PDCCH only in a specific subframe, and continuous PDCCH monitoring means that the UE monitors the PDCCH in all subframes. On the other hand, when PDCCH monitoring is required in a DRX-independent operation such as a random access procedure, the UE monitors the PDCCH according to the requirements of the corresponding operation.

In other words, DRX refers to a function that allows the UE to stop monitoring the PDCCH for a predetermined period (i.e., a sleep period or a non-active time) (Wake up or active) and sleep (sleep or non-active) periods. Wake-up (or activity) means monitoring the packet data control channel (PDCCH). The sleep (or inactivity) means stop monitoring the packet data control channel (PDCCH).

The DRX may be configured by radio resource control / media access control (RRC / MAC). Related DRX parameters may include a long DRX cycle, a DRX inactivity timer, and a DRX retransmission timer. Also optionally, DRX includes a short DRX cycle and a DRX short cycle timer (drxShortCycleTimer). The long DRX cycle provides a longer sleep period for the UE than the short DRX cycle.

6 is a conceptual diagram showing a DRX operation applied to the present invention.

Referring to FIG. 6, the DRX operation is repeated in a DRX cycle (600). The DRX cycle 600 is a periodic repetition of a DRX opportunity (DRX) 610 and an On Duration (605) Is defined. That is, a DRX cycle 600 of one cycle includes a duration 605 and a DRX opportunity 610. [ The DRX cycle 600 is, for example, a long DRX cycle that is applied in a range between 10 subframes and 2560 subframes. In another example, a short DRX cycle (a short DRX cycle) applied in the range of 2 subframes to 640 subframes DRX cycle). At this time, the short DRX cycle is applied only while the DRX short cycle timer (drxShortCycleTimer) is operating, and the long DRX cycle is applied in the range outside the DRX short cycle timer. Here, the DRX short-cycle timer is one basic DRX cycle. At this time, the length of the short-term DRX cycle timer may be 1 to 16, for example. Term DRX mode when the terminal is operating in the short-term DRX cycle, or a long-term DRX mode when operating in the long-term DRX cycle.

The RRC layer manages several timers to control the DRX operation. The timer for controlling the DRX operation includes a duration timer (onDurationTimer), a DRX Inactivity Timer (DRX Inactivity Timer), and a DRX Retransmission Timer (DRX Retransmission Timer).

The duration timer is started by the start of the DRX cycle. That is, the start time of the sustain interval timer coincides with the start time of the DRX cycle. The duration timer increases by 1 for every PDCCH subframe. And the duration timer expires when the duration timer value equals a preconfigured expiration value. The sustain interval timer is valid until the sustain interval timer value becomes equal to the expiration value.

The DRX inactivity timer may be defined as the number of consecutive PDCCH subframes from the point in time at which the PDCCH for uplink or downlink user data transmission is successfully decoded. It is time for the UE to continuously monitor the PDCCH since continuous data reception may occur. The DRX inactivity timer is started or restarted when the UE successfully decodes the PDCCH for the HARQ initial transmission in the PDCCH subframe.

The DRX Retransmission Timer is a timer that operates based on the maximum number of consecutive numbers of PDCCH subframes expected to be DL retransmitted by the UE. The DRX retransmission timer is a timer that is started when the HARQ RTT timer has expired but fails to receive the retransmission data. The UE can monitor reception of data retransmitted in the HARQ process while the DRX retransmission timer is in progress. The configuration of the DRX Retransmission Timer is defined by the MAC-MainConfig message of the RRC layer.

The duration of the duration timer, DRX inactivity timer, or DRX retransmission timer is referred to as active time. Or the activity time may refer to all the intervals that the terminal is awake. The non-active time in the DRX cycle 600 may be referred to as a non-active time. The activity time may be referred to as a wake up period, and the inactivity time may be referred to as a sleep period. The terminal monitors the PDCCH for the PDCCH subframe (PDCCH subframe) during the active time. Here, the PDCCH subframe means a subframe including a PDCCH. For example, in a TDD configuration, downlink subframes and downlink pilot time slot (DwPTS) subframes correspond to a PDCCH subframe. A timer unit of a DRX timer such as a duration timer, a DRX inactivity timer, or a DRX retransmission timer is a PDCCH subframe (psf). That is, the DRX timers are counted based on the number of PDCCH subframes.

In addition, there are a long DRX cycle (longDRX-Cycle) and a DRX start offset (drxStartOffset) as parameters for controlling the DRX operation. The base station optionally sets a DRX short cycle timer (drxShortCycleTimer) and a short DRX- . In addition, a HARQ round trip time (RTT) timer is defined for each downlink HARQ process.

The DRX start offset is a value defining the subframe in which the DRX cycle 500 begins. The DRX short cycle timer is a timer that defines the number of consecutive subframes for which the UE must follow a short DRX cycle. The HARQ RTT timer is a timer that defines the minimum number of subframes prior to an interval in which a UE is expected to receive a downlink HARQ retransmission.

Meanwhile, the DRX configuration information may be received in a MAC-MainConfig message, which is an RRC message used to specify a main configuration of a MAC layer for a signaling radio bearer (SRB) and a data radio bearer (DRB). The DRX configuration information can be configured, for example, as shown in the following table.

DRX-Config :: = CHOICE {
release NULL,
setup SEQUENCE {
onDurationTimer ENUMERATED {
pSF1, pSF2, pSF3, pSF4, pSF5, pSF6,
psf8, psf10, psf20, psf30, psf40,
psf50, psf60, psf80, psf100, psf200},
DRx-InactivityTimer ENUMERATED {
pSF1, pSF2, pSF3, pSF4, pSF5, pSF6,
psf8, psf10, psf20, psf30, psf40,
psf50, psf60, psf80, psf100,
psf200, psf300, psf500, psf750,
psf1280, psf1920, psf2560, psf0-v1020,
spare9, spare8, spare7, spare6,
spare5, spare4, spare3, spare2,
spare1},
DRx-RetransmissionTimer ENUMERATED {
psf1, psf2, psf4, psf6, psf8, psf16,
psf24, psf33},
longDRX-CycleStartOffset CHOICE {
sf10 INTEGER (0..9),
sf20 INTEGER (0..19),
sf32 INTEGER (0..31),
sf40 INTEGER (0..39),
sf64 INTEGER (0..63),
sf80 INTEGER (0..79),
sf128 INTEGER (0..127),
sf160 INTEGER (0..159),
sf256 INTEGER (0..255),
sf320 INTEGER (0..319),
sf512 INTEGER (0..511),
sf640 INTEGER (0..639),
sf1024 INTEGER (0..1023),
sf1280 INTEGER (0..1279),
sf2048 INTEGER (0..2047),
sf2560 INTEGER (0..2559)
},
shortDRX SEQUENCE {
shortDRX-Cycle ENUMERATED {
sf2, sf5, sf8, sf10, sf16, sf20,
sf32, sf40, sf64, sf80, sf128, sf160,
sf256, sf320, sf512, sf640},
drxShortCycleTimer INTEGER (1..16)
} OPTIONAL - Need OR
}
}

Referring to Table 1, the DRX configuration information includes an onDurationTimer field for defining a value of a duration timer, a drx-InactivityTimer field indicating a value of the DRX inactivity timer, and a drx-RetransmissionTimer field indicating a value of the DRX retransmission timer do. The DRX configuration information also includes a longDRX-CycleStartOffset field indicating the length of the long DRX cycle and a starting subframe, and a shortDRX field related to the short-term DRX that can be optionally configured. The short DRX field specifically includes a short DRX-Cycle subfield indicating the length of the short DRX cycle and a drxShortCycleTimer subfield indicating the value of the successive short DRX cycle timer.

The onDurationTimer field may be set to any one of the values of {psf1, psf2, psf3, ... psf200}. psf denotes a PDCCH subframe, and the number after psf denotes the number of PDCCH subframes. That is, psf represents the expiration value of the timer as the number of PDCCH subframes. For example, if the onDurationTimer field = psf1, the duration timer expires after progressing cumulatively to one PDCCH subframe including the subframe where the DRX cycle started. Or the onDurationTimer field = psf4, the duration timer expires after progressing from the beginning of the DRX cycle cumulatively to the four PDCCH subframes. The drx-InactivityTimer field may be set to any one of the values of {psf1, psf2, psf3, ... psf2560}. For example, if the drx-InactivityTimer field = psf3, the DRX inactivity timer expires after progressing up to three PDCCH subframes cumulatively, including the subframe at the time of driving. The drx-RetransmissionTimer field may be set to one of the values of {psf1, psf2, psf4, ... psf33}. For example, if the drx-RetransmissionTimer field = psf4, the DRX Retransmission Timer expires after progressing up to four PDCCH subframes cumulatively including the subframe at the time of being driven.

The longDRX-CycleStartOffset field may be set to one of the values of {sf10, sf20, sf32, sf40, ... sf2560} as the length of the long DRX cycle, and the subframe at which the long DRX cycle starts is the length of the long DRX cycle INTEGER (0..39), ... INTEGER (0..2559)} values corresponding to the values of the values of [ For example, if the longDRX-CycleStartOffset field = sf20, INTEGER (0..19), then one long DRX cycle includes 20 subframes, and the long DRX cycle may be any subframe Can be selected as the long-term DRX cycle start sub-frame. The shortDRX-Cycle subfield constituting the shortDRX field may be set to any one of the values of {sf2, sf5, sf8, ... sf640}. For example, if the shortDRX-Cycle subfield = sf5, then one short DRX cycle includes five subframes. In addition, the drxShortCycleTimer subfield constituting the shortDRX field may represent any one of the integers 1 to 16. For example, if the drxShortCycleTimer subfield = 3, the short DRX cycle expires three times.

Meanwhile, in a wireless communication system, it is necessary to estimate an uplink channel or a downlink channel for data transmission / reception, system synchronization acquisition, channel information feedback, etc., and compensates for signal distortion caused by a sudden change in environment. The process of restoring the signal is called channel estimation. It is also necessary to measure the channel state of the cell or other cell to which the terminal belongs. Generally, a transceiver uses a reference signal (RS) known to each other for channel estimation or channel state measurement.

The downlink reference signal includes a cell-specific RS (CRS), a mobile broadcast single frequency network (MBSFN) reference signal, a UE-specific RS, a positioning RS (PRS) And a CSI (Channel State Information) reference signal (CSI-RS).

Among them, the CRS is used as a reference signal transmitted to all terminals in a cell for channel estimation. In the case of the legacy carrier type, the CRS is transmitted in all downlink subframes in the cell supporting PDSCH transmission.

7 shows an example of a CRS transmission in a DL sub-frame and a DRX operation of a UE in case of a legacy carrier type. The hatched portion indicates the subframe in which the CRS is transmitted. The same shall apply hereinafter. In this example, the on duration timer is psf (PDCCH subframe) 3, the long DRX cycle is sf (subframe) 10, and the DRX offset is sf2 in the DRX operation. Hereinafter, it is assumed that the PDCCH is included in all downlink subframes for convenience of understanding.

Referring to FIG. 7, in the case of the legacy carrier type, the CRS is transmitted in all the downlink subframes in the serving cell. In the case of DRX, the DRX periodicity starts from the second subframe, and the UE operates at the active time during three subframes from the beginning of the DRX cycle, with 10 subframes being a long DRX cycle. In this case, the terminal can smoothly receive the CRS.

However, in a multi-carrier system, all element carriers transmit and receive reference signals such as CRS in the physical layer, thereby reducing the data area to be transmitted, which is inefficient. Therefore, in the case of the NCT, it is possible to use the TRS (Trace Reference Signal) or the reduced CRS in which the CRS is transmitted with a certain period, Signal can be transmitted.

FIG. 8 shows an example of a reduced CRS transmission and a DRX operation of a UE in a downlink subframe in the case of an NCT. In this example, the duration timer in the DRX operation is psf3, the long DRX cycle is sf10, and the DRX offset is sf2.

Referring to FIG. 8, the NCT may include a reduced CRS transmitted with a period of sf5 (or 5 ms period). For example, the reduced CRS may be transmitted to the mobile station in the 0th subframe, the 5th subframe, the 10th subframe, and so on. Meanwhile, when the DRX cycle starts from the 2nd subframe in the DRX operation of the UE, The UE can not receive the reduced CRS since the UE does not transmit the reduced CRS during the subframe in the persistent interval time, i.e., the active time.

FIG. 9 shows an example of a CRS transmission and a DRX operation of a terminal when a terminal uses a legacy carrier type and an NCT simultaneously in a multi-carrier system. In this example, the primary serving cell (Pcell) is a legacy carrier type and the secondary serving cell (Scell) is an NCT. That is, this example uses a carrier aggregation (CA) scheme in which a legacy carrier is used as a main serving cell (Pcell) and an NCT is used as a secondary serving cell (Scell). In this example, the duration timer in the DRX operation is psf3, the long DRX cycle is sf10, and the DRX offset is sf2.

Referring to FIG. 9, in the case where only the main serving cell of the legacy carrier type is used, the UE can receive the CRS and measure the channel state even in the DRX operation. However, if the terminal uses the secondary serving cell of the NCT, it is difficult to accurately measure the secondary serving cell of the NCT with the existing DRX setting. Specifically, the cell measurement of the UE is basically a process of receiving the CRS and measuring the channel state. However, in FIG. 9, when the UE proceeds with the DRX operation in accordance with the DRX setting, the UE can not receive the CRS because the period during which the CRS is transmitted in the NCT inactive serving cell is always a non-active period. If the terminal wakes up and becomes active in an inactive period in order to receive the CRS in the serving cell of the NCT, the UE will not meet the DRX objective of reducing the battery consumption of the terminal.

Therefore, even if the UE has a DRX configuration considering only the existing main carrier cell of the legacy carrier type, if the UE additionally uses the auxiliary serving cell of the NCT, DRX reconfiguration is preferably performed considering the characteristics of the NCT .

In order to solve the above-mentioned problems, a method of performing DRX reconfiguration considering a NCT is proposed by a terminal and a base station.

10 illustrates a DRX operation considering an NCT in a multi-carrier system according to an exemplary embodiment of the present invention. In this example, the DRX cycle starts from the second subframe in the DRX operation (i.e., the DRX offset is sf2), the sustain interval timer is psf5, and the long DRX cycle is sf10.

If the UE uses the NCT sub-serving cell, the BS may reconfigure the DRX duration timer and the like considering the reduced CRS mapping in the NCT secondary serving cell, unlike the CRS mapping in the main serving cell do.

Referring to FIG. 10, if the transmission period of the reduced CRS of the NCT is sf5 (or 5 ms), the UE and the BS can reconstruct the existing duration time from sf3 to sf5 so that the UE can receive the reduced CRS at the active time have.

11 illustrates a DRX operation considering an NCT in a multi-carrier system according to another example of the present invention. In this example, the DRX cycle starts from the 0th subframe in the DRX operation (i.e., the DRX offset is sf0), the sustain interval timer is psf5, and the long DRX cycle is sf10.

Referring to FIG. 11, in this example, the duration time is reconstructed to sf5 according to the transmission period sf5 (or 5 ms) of the reduced CRS of the NCT. In addition, the beginning of the first reduced CRS transmission of the NCT secondary serving cell and the duration of the duration (i.e., activity time) were reconfigured to align.

In general, the DRX configuration is performed on a per-terminal basis. That is, the DRX configuration is configured based on one terminal. In particular, even in the case of a carrier aggregation, even when considering a plurality of serving cells distinguished as a primary serving cell or a secondary serving cell, it is difficult to perform multiple DRX configurations per UE because of complexity and efficiency, One DRX configuration per terminal is performed. Therefore, when the main serving cell and the NCT secondary serving cell of the legacy carrier type are used, it is necessary to reconstruct the DRX considering the situation such as the reduced CRS (or TRS) for the measurement of the NCT secondary serving cell . At this time, the DRX reconfiguration can be performed through the RRC connection reconfiguration message. However, if the UE receives the information about the reduced CRS (or TRS), and the reduced CRS information (Reduced RS Info), even if the DRX reconstruction is not explicitly performed through the RRC connection reconfiguration message, Configuration and, if necessary, implicitly perform DRX reconstruction. That is, the base station may inform the terminal of the reduced CRS information of the NCT, for example, the offset of the period of the reduced CRS and the starting (or changing) point of the reduced CRS. The cycle and offset of the reduced CRS can be viewed as a constant value that is maintained once until it is determined once in the NCT and before it is again reconstructed. Therefore, the reduced CRS information including the period and the offset of the reduced RS is a static or semi-static value, and is transmitted from the base station to the base station through the system information of the broadcast channel. Or may be transmitted from the base station to the mobile station through dedicated signaling of a dedicated channel.

FIG. 12 shows reduced CRS information transmission through a broadcast control channel (BCCH) according to an exemplary embodiment of the present invention.

Referring to FIG. 12, the reduced CRS information may be included in the system information. That is, the BS can broadcast the reduced CRS information to the MS through a broadcast control channel (S1200). The reduced CRS information may include at least one of a period and an offset value of the reduced CRS.

In one example, the reduced CRS information may include both a period and an offset value of the reduced CRS. Here, the period value of the reduced CRS may be set to sf5 in units of subframes or 5 ms in units of time, or may be indicated as an explicitly different value. The offset value indicates a starting point of the reduced CRS in the subframe of the radio frame.

As another example, the reduced CRS information may include an offset value. The period of the reduced CRS may be predetermined to sf5 (or 5 ms), and in this case, the reduced CRS information may be transmitted to the UE including the offset value excluding the period value of the reduced CRS.

FIG. 13 shows reduced CRS information transmission over a dedicated control channel (DCCH) according to another example of the present invention.

Referring to FIG. 13, the reduced CRS information may be transmitted specifically to the UE, and thus may be transmitted from the BS to the UE through a dedicated control channel (DCCH) as a logical channel (S1300). For example, the reduced CRS information may be transmitted via an RRC Connection Reconfiguration message. Specifically, the RRC connection reconfiguration message conveys information for measurement configuration, mobility control, and radio resource configuration. For example, the reduced CRS information may include RRC reconfiguration The message may be included as information for radio resource configuration.

The reduced CRS information may include at least one of a period and an offset value of the reduced CRS.

In one example, the reduced CRS information may include both a period and an offset value of the reduced CRS. Here, the period value of the reduced CRS may be set to sf5 in units of subframes or 5 ms in units of time, or may be indicated as an explicitly different value. The offset value indicates a starting point of the reduced CRS in the subframes of the radio frame.

As another example, the reduced CRS information may include an offset value. The period of the reduced CRS may be predetermined to sf5 (or 5 ms), and in this case, the reduced CRS information may be transmitted to the UE including the offset value excluding the period value of the reduced CRS.

Specifically, the reduced CRS information may be configured as follows in an RRC connection reconfiguration message.

SCellToAddModList-r10 :: = SEQUENCE (SIZE (1..maxSCell-r10)) OF SCellToAddMod-r10

SCellToAddMod-r10 :: = SEQUENCE {
sCellIndex-r10 SCellIndex-r10,
cellIdentification-r10 SEQUENCE {
physCellId-r10 PhysCellId,
dl-CarrierFreq-r10 ARFCN-ValueEUTRA
trsPeriod TRS-Period
trsOffset TRS-Offset
} OPTIONAL, - Cond SCellAdd
radioResourceConfigCommonSCell-r10 RadioResourceConfigCommonSCell-r10 OPTIONAL, - Cond SCellAdd
radioResourceConfigDedicatedSCell-r10 RadioResourceConfigDedicatedSCell-r10 OPTIONAL, - Cond SCellAdd2
...
}

Referring to Table 2, the RRC connection reconfiguration message includes a SCellToAddModList which is an information element (IE) for adding a serving cell. The size of SCellToAddModList can be set from 1 to the maximum number of sub-serving cells (maxScell). SCellToAddMod may further include a serving cell index and a cell ID to be added, as well as a TRS-Period and a TRS-Offset. The TRS-Period indicates the period in which the reduced CRS (or TRS) is transmitted. The TRS-Offset indicates the first starting point of the reduced CRS (or TRS). That is, the TRS-Offset may indicate from which subframe the first CRS (or TRS) is transmitted in the first starting subframe of the radio frame. The TRS-Period may be referred to as a Reduced CRS-Period, and the TRS-Offset may be referred to as a Reduced CRS-Offset. On the other hand, if the TRS-Period is fixed to sf5 (or 5ms), the TRS-Period may be omitted.

FIG. 14 shows a configuration of an NCT secondary serving cell and DRX reconstruction according to an exemplary embodiment of the present invention.

Referring to FIG. 14, the base station performs an RRC connection reconfiguration procedure to further configure one or more NCT secondary serving cells to the terminal (S1400). At this time, the NCT secondary serving cell configuration information may be included in the RRC connection reconfiguration message and transmitted to the UE. The addition of the NCT secondary serving cell can be performed, for example, in a case where a more requesting radio resource needs to be allocated to the terminal by the request of the terminal, the request of the network, or the self-determination of the base station. Adding an NCT secondary serving cell to a terminal or removing an NCT secondary serving cell configured in the terminal may be indicated by an RRC connection reconfiguration message. The RRC connection reconfiguration message includes reduced CRS information of the NCT secondary serving cell. The reduced CRS information includes at least one of a reduced CRS period and reduced CRS offset information. For example, if the reduced CRS period is predefined such as sf5 (5 ms), the reduced CRS period information may be omitted. The RRC connection reconfiguration procedure may include a step in which the Node B transmits an RRC connection reconfiguration message to the UE, the UE configures the NCT secondary serving cell at the UE, and the UE transmits an RRC connection reconfiguration completion message to the Node B.

The RRC connection reconfiguration procedure includes a base station transmitting an RRC connection reconfiguration message to the UE, and a UE transmitting an RRC connection reconfiguration completion message to the base station.

The base station transmits an NCT secondary serving cell activation indicator for activating the configured NCT secondary serving cell to the terminal (S1410). For example, when the BS desires to schedule the NCT secondary serving cell, the BS can transmit the NCT secondary serving cell activation indicator for activating the NCT secondary serving cell to the MS. The NCT secondary serving cell activation indicator may be transmitted to the UE through a MAC message.

The MS performs an RRC connection reconfiguration procedure for DRX reconfiguration (S1420). When the base station and the UE judge that the DRX reconfiguration is necessary by adding the NCT secondary serving cell to the DRX configuration that was already set up when only the main serving cell exists or when the secondary serving cell of the legacy carrier type is additionally configured, The RRC connection reconfiguration procedure for the DRX reconfiguration can be performed. The RRC connection reconfiguration procedure for the DRX reconfiguration may be performed considering at least one of the period and the offset of the reduced CRS of the NCT secondary serving cell. The RRC connection reconfiguration procedure for the DRX reconfiguration is a procedure in which the base station performs DRX reconfiguration and transmits related DRX parameters to the UE through an RRC connection reconfiguration message and the UE performs DRX reconfiguration at the UE based on the DRX parameters And transmitting the RRC connection reconfiguration completion message to the base station.

Although FIG. 14 shows that S1420 is performed after S1410, this is only an example, and may be performed before S1410.

15 shows a configuration of an NCT secondary serving cell and a DRX reconstruction according to another example of the present invention. FIG. 15 shows a process of implicitly performing DRX reconstruction in the UE and the BS through the NCT secondary serving cell configuration information or the NCT secondary serving cell indicator.

Referring to FIG. 15, the BS and the UE perform an RRC connection reconfiguration procedure to configure one or more NCT secondary serving cells to the UE (S1500). At this time, the NCT secondary serving cell configuration information may be included in the RRC connection reconfiguration message and transmitted to the UE. The RRC connection reconfiguration message includes reduced CRS information of the NCT secondary serving cell. The reduced CRS information includes at least one of a reduced CRS period and reduced CRS offset information. For example, if the reduced CRS period is predefined such as sf5 (5 ms), the reduced CRS period information may be omitted. The RRC connection reconfiguration procedure may include a step in which the Node B transmits an RRC connection reconfiguration message to the UE, the UE configures the NCT secondary serving cell at the UE, and the UE transmits an RRC connection reconfiguration completion message to the Node B.

The base station transmits an NCT secondary serving cell activation indicator for activating the added NCT secondary serving cell to the terminal (S1510). The NCT secondary serving cell activation indicator may be transmitted to the UE through a MAC message. The MAC message including the NCT secondary serving cell activation indicator may be configured as follows, for example.

16 shows a structure of a MAC message to which the present invention is applied.

16, a MAC message 1600 includes a MAC header 1610, at least one MAC control element 1620, ..., 1625, at least one MAC Service Data Unit (SDU) (1630-1, ..., 1630-m) and padding (1640).

The MAC header 1610 includes at least one sub-header 1610-1, 1610-2, ..., 1610-k, and each sub-header 1610-1, 1610-2, ..., ., 1610-k correspond to one MAC SDU or one MAC control element 1620, ..., 1625 or padding 1640. The order of the subheaders 1610-1, 1610-2, ..., 1610-k is the same as the corresponding MAC SDU, MAC control element 1620, ..., 1625 or padding 1640 ).

Each of the subheaders 1610-1, 1610-2, ..., and 1610-k includes four fields such as R, R, E, and LCID, or R, R, E, LCID, Field. The subheader including the four fields is a subheader corresponding to the MAC control element 1620, ..., 1625 or the padding 1640, and the subheader including the six fields is a subheader corresponding to the MAC SDU .

The Logical Channel ID (LCID) field is an identification field that identifies a logical channel corresponding to a MAC SDU or identifies a MAC control element 1620, ..., 1625 or a type of padding, When the subheaders 1610-1, 1610-2, ..., 1610-k have an octet structure, the LCID field may be 5 bits.

For example, the LCID field includes a MAC control element (hereinafter referred to as an Activation MAC CE) for instructing activation / deactivation of a serving cell, as shown in Table 3, Quot;).

Index (Index) LCID value (value) 00000 CCCH 00001-01010 Identity of the logical channel < RTI ID = 0.0 > 01011-11010 Reserved 11011 Activation / Deactivation 11100 A UE Contention Resolution Identity (UE Contention Resolution Identity) 11101 Timing Advance Command 11110 The DRX command (DRX command) 11111 Padding

Referring to Table 3, if the value of the LCID field is 11011, the corresponding MAC control element is the MAC control element for activation / deactivation.

MAC control elements 1620, ..., and 1625 are control messages generated by the MAC layer. A padding 1640 is a predetermined number of bits added to make the size of the MAC message constant. MAC control elements 1620 ... 1625, MAC SDUs 1630-1 through 1630-m, and padding 1640 are collectively referred to as a MAC payload. An example of a MAC control element for activation is disclosed below.

17 is a block diagram illustrating the structure of a MAC control element according to an exemplary embodiment of the present invention. This represents the MAC control element for activation / deactivation. 18 shows an example of a MAC control element for instructing activation of an NCT secondary serving cell according to an example of the present invention.

Referring to FIG. 17, the MAC CE 1750 for activation / deactivation includes octet 1 (OCT 1). One octet is 8 bits, which includes information about the activation / deactivation of the serving cell and the carrier type. The MAC CE 1750 for activation / deactivation specifically includes seven C _i fields 1755 and an R field 1760. The C _i field 1755 includes C ₇ , C ₆ , C ₅ , C ₄ , C ₃ , C ₂ , and C ₁ fields. C _i Field 1755 indicates the activation / deactivation state for the secondary serving cell of index i. For example, C ₁ If the field is 0, it may indicate the deactivation of the first-part serving cell, and if it is equal to 1, it may indicate the activation of the first-part serving cell. R field 1760 may be used as a distinguisher to distinguish legacy carrier type from NCT. For example, if the R field 1760 is 0, the secondary serving cell indicates a legacy carrier type, and if the R field 1760 is 1, the secondary serving cell indicates an NCT have. The R field 1760 may be referred to as an F field or the like depending on agreement between the UE and the BS.

For example, as shown in FIG. 18, when the R field is set to 1 and the C ₂ field is set to 1, it is possible to indicate that the second sub-serving cell with the carrier type of NCT is activated. Through this, the UE can activate the NCT secondary serving cell. Although FIGS. 17 and 18 illustrate the case where the MAC CE for activating / deactivating simultaneously indicates whether the serving cell is activated / deactivated and whether the serving cell is NCT, the MAC CE for activation / It is of course also possible to indicate only whether to activate / deactivate, and whether the carrier type of the secondary serving cell to be activated / deactivated is NCT may be indicated through a separate indicator.

Referring again to FIG. 15, when the UE receives an activation indicator for activating the NCT secondary serving cell, the UE activates the NCT secondary serving cell and performs wireless communication through the activated NCT secondary serving cell . On the other hand, when the UE operates based on the DRX configuration that is configured (or reconstructed) based on the main serving cell of the legacy carrier type, the reference signal such as the reduced CRS may not be received as described above. Accordingly, when the BS and the UE transmit / receive the activation indicator for activating the NCT secondary serving cell, the DRX reconfiguration can be performed considering the current DRX configuration and the reduced CRS information. In this case, the terminal can perform DRX reconfiguration itself on the basis of the current DRX configuration and the reduced CRS information without receiving the RRC connection reconfiguration message including DRX parameters from the base station (S1520). In this case, it is natural that the base station can perform the DRX reconfiguration corresponding to the DRX reconfiguration at the terminal at the base station. In this case, DRX reconfiguration based on the current DRX configuration and the reduced CRS information may be predefined (or promised) between the UE and the BS. For example, the UE can perform DRX reconfiguration at the UE if the duration of the DRX operation is smaller than the decremented CRS period (in terms of time). Here, if the sustain period timer value is smaller than the decremented CRS period (in terms of time), the time value is calculated assuming that the sustain period timer unit psf is expressed in units of sf, or the PDCCH is transmitted in all downlink subframes , It may mean that the sustain period timer value is smaller than the decrease CRS period value when compared with a time value calculated based on the minimum possible time. The same shall apply hereinafter.

For example, the UE can adjust the size of the duration timer of the DRX operation to be equal to or longer than the period of the reduced CRS considering the period of the reduced CRS. That is, if the duration timer is less than the duration of the reduced CRS, the UE may replace the value of the duration timer with a value equal to or somewhat larger than the periodicity of the reduced CRS. Meanwhile, if the duration timer is equal to or shorter than the period of the reduced CRS, the UE can maintain the value of the duration timer. By configuring the persistent interval timer to be at least equal to or longer than the period of the reduced CRS, the UE receives the reduced CRS in the interval in which the UE has a reduced CRS of the NCT secondary serving cell at least once during the active period, Can be performed. Specifically, for example, in the DRX operation as described above, the duration timer is psf3, the long DRX cycle is sf10, the DRX offset is sf2, the reduced CRS cycle is sf5, and the reduced CRS offset is sf0 have. At this time, the UE can perform the DRX reconstruction with the DRX sustain interval timer psf5 as in the example of FIG. 10 described above so that the UE can smoothly receive the reduced CRS at the active time. Also, at this time, since the base station knows the existing DRX configuration of the UE and knows the period of the reduced CRS, the changed DRX configuration is known, and DRX reconfiguration can be performed at the base station based on the changed DRX configuration. In this case, the BS may not transmit the RRC connection reconfiguration message including the reconfigured DRX parameter to the UE for DRX reconfiguration of the UE.

As another example, the terminal may adjust the DRX offset value by considering the offset value of the reduced CRS. Through this, the UE can match the start of the DRX duration (or activity time) with the subframe in which the reduced CRS is provided. Specifically, for example, in the DRX operation as described above, the duration timer is psf3, the long DRX cycle is sf10, the DRX offset is sf2, the reduced CRS cycle is sf5, and the reduced CRS offset is sf0 have. At this time, since the DRX offset is sf2, it can be seen that the DRX duration (or activity time) starts at a difference of two subframes at the beginning of the radio frame. On the other hand, since the reduced CRS offset is 0, the terminal can change the DRX offset in this case to the same value as the reduced CRS offset. That is, if the DRX offset is different from the reduced CRS offset, the UE can perform the DRX reconstruction with a value equal to the reduced CRS offset. Also, at this time, since the base station knows the existing DRX configuration of the UE and knows the offset of the reduced CRS, it can know the changed DRX configuration and perform DRX reconfiguration at the base station based on the changed DRX configuration. In this case, the BS may not transmit the RRC connection reconfiguration message including the reconfigured DRX parameter to the UE for DRX reconfiguration of the UE.

As another example, the UE may adjust the DRX offset value in consideration of the offset value of the reduced CRS as well as the DRX duration timer in consideration of the period of the reduced CRS. That is, if the DRX duration timer is smaller than the period of the reduced CRS, the UE sets the DRX duration timer to a value equal to or greater than the period of the reduced CRS, and if the DRX offset value is different from the reduced CRS offset value , The DRX offset value may be set to the reduced CRS offset value. In this case, the UE shall allow the UE to receive the reduced CRS in the interval in which there is a reduced CRS of the NCT secondary serving cell at least once during the duration of the active period, Activity time) can be matched. Specifically, for example, in the DRX operation as described above, the duration timer is psf3, the long DRX cycle is sf10, the DRX offset is sf2, the reduced CRS cycle is sf5, and the reduced CRS offset is sf0 have. At this time, the UE (and the base station) can perform the DRX reconstruction with the DRX sustain interval timer as psf5 and the DRX offset as sf0 as shown in FIG. 14, thereby allowing the UE to smoothly receive the reduced CRS at the active time . Also, at this time, since the base station knows the existing DRX configuration of the UE and knows the period and offset of the reduced CRS, the changed DRX configuration is also known, and DRX reconfiguration can be performed at the base station based on the changed DRX configuration. In this case, the BS may not transmit the RRC connection reconfiguration message including the reconfigured DRX parameter to the UE for DRX reconfiguration of the UE.

In the example of FIG. 15, DRX reconfiguration is performed when the UE receives the NCT secondary serving cell activation indicator, but this is merely an example. The RRC DRX reconfiguration is performed without waiting for reception of the NCT secondary serving cell activation indicator when the NCT secondary serving cell is configured in the terminal or when the terminal transmits the RRC connection reconfiguration completion message to the base station by performing the connection reconfiguration procedure It is possible. In this case, since the UE can acquire the reduced CRS information of the NCT secondary serving cell through the RRC connection reconfiguration procedure, the UE can perform the DRX reconfiguration at the UE based on the DRX configuration information of the UE itself and the reduced CRS information have. In addition, since the base station knows the DRX configuration information of the UE and the reduced CRS information of the NCT secondary serving cell, the base station can perform DRX reconfiguration at the base station. In such a case, the UE and the BS can change the DRX configuration without transmitting / receiving a separate RRC connection reconfiguration message for the DRX reconfiguration procedure, so that the UE can smoothly receive the reduced CRS of the NCT secondary serving cell .

FIG. 19 shows a DRX reconstruction method considering an NCT performed in a terminal according to an exemplary embodiment of the present invention.

Referring to FIG. 19, the UE performs an RRC connection reconfiguration procedure to further configure one or more NCT secondary serving cells to the UE (S1900). Adding an NCT secondary serving cell to a terminal or removing an NCT secondary serving cell configured in the terminal may be indicated by an RRC connection reconfiguration message. That is, the NCT secondary serving cell configuration information is included in the RRC connection reconfiguration message and can be received by the UE. The RRC connection reconfiguration message includes reduced CRS information of the NCT secondary serving cell. The reduced CRS information includes at least one of a reduced CRS period and reduced CRS offset information. For example, if the reduced CRS period is predefined such as sf5 (5 ms), the reduced CRS period information may be omitted. The RRC connection reconfiguration procedure may include the step of the terminal receiving the RRC connection reconfiguration message from the base station, the terminal configuring the NCT secondary serving cell at the terminal end, and the terminal transmitting the RRC connection reconfiguration completion message to the base station. In this case, the BS and the UE can know that the NCT secondary serving cell is configured. For example, the base station can explicitly inform the terminal that the newly configured cell is an NCT secondary serving cell. Alternatively, the UE may know whether the NCT sub-serving cell is configured based on whether information included only in the setting of the NCT secondary serving cell (for example, reduced CRS information or the like) is included.

The MS receives from the BS an NCT secondary serving cell activation indicator for activating the added NCT secondary serving cell (S1910). The NCT secondary serving cell activation indicator may be received at the terminal through a MAC message. The MAC message may include the MAC CE of FIG. 21 described above. When the UE receives an activation indicator for activating the NCT secondary serving cell, the UE activates the NCT secondary serving cell.

In step S1920, the UE determines whether the value of the DRX configuration duration timer is smaller than the reduced CRS period. The UE can compare the value of the persistent interval timer with the decrease CRS period value based on the reduced CRS information included in the RRC connection reconfiguration message received from the base station in step S2200. Alternatively, the UE may compare the duration timer value with the decreased CRS period value based on the predefined reduced CRS period information.

If the value of the sustain interval timer is smaller than the decrease CRS period in step S1920, DRX reconfiguration is performed according to a predefined criterion between the UE and the BS in step S1930.

For example, the UE can adjust the size of the duration timer of the DRX operation to be equal to or longer than the period of the reduced CRS considering the period of the reduced CRS. That is, if the duration timer is less than the duration of the reduced CRS, the UE may replace the value of the duration timer with a value equal to or somewhat larger than the periodicity of the reduced CRS. By configuring the duration timer at least equal to or longer than the period of the reduced CRS as described above, the UE receives the reduced CRS in a period in which the UE has a reduced CRS of the NCT secondary serving cell at least once during the duration of the active period Measurement can be performed.

As another example, the terminal may adjust the DRX offset value by considering the offset value of the reduced CRS. Through this, the UE can match the start of the DRX duration (or activity time) with the subframe in which the reduced CRS is provided. That is, if the DRX offset is different from the reduced CRS offset, the UE can perform the DRX reconstruction with a value equal to the reduced CRS offset.

As another example, the UE may adjust the DRX offset value in consideration of the offset value of the reduced CRS as well as the DRX duration timer in consideration of the period of the reduced CRS. That is, if the DRX duration timer is smaller than the period of the reduced CRS, the UE sets the DRX duration timer to a value equal to or greater than the period of the reduced CRS, and if the DRX offset value is different from the reduced CRS offset value , The DRX offset value may be set to the reduced CRS offset value. In this case, the UE shall allow the UE to receive the reduced CRS in the interval in which there is a reduced CRS of the NCT secondary serving cell at least once during the duration of the active period, Activity time) can be matched.

In this case, the UE can implicitly perform the DRX reconfiguration without receiving the RRC connection reconfiguration message including the DRX-related parameter explicitly from the base station.

If it is determined in step S1920 that the value of the persistent interval timer is equal to or less than the decrease CRS period, the UE keeps the value of the persistent interval timer as it is. In this case, the RRC connection reconfiguration DRX reconfiguration may not be performed until a message is received.

19, steps S1920 and S1930 are performed after step S1910, but steps S1920 and S1930 may be performed when the UE configures the NCT secondary serving cell at the terminal end in step S1900, or when the UE transmits the RRC connection reconfiguration completion message To the base station. In other words, when the UE configures the NCT secondary serving cell or transmits the RRC connection reconfiguration complete message to the BS through the RRC connection reconfiguration procedure in step S1900, the Node B does not yet activate the serving cell, The serving cell is recognized as a usable spare cell, and the DRX reconfiguration described above can be performed according to a predefined criterion between the UE and the BS. Accordingly, after step S1900, step S1920 may be performed without step S1910.

20 shows a DRX reconstruction method considering NCT performed in a base station according to an example of the present invention.

Referring to FIG. 20, a base station performs an RRC connection reconfiguration procedure to further configure one or more NCT secondary serving cells to a terminal (S2000). Adding an NCT secondary serving cell to a terminal or removing an NCT secondary serving cell configured in the terminal may be indicated by an RRC connection reconfiguration message. That is, the NCT secondary serving cell configuration information may be included in the RRC connection reconfiguration message and transmitted to the UE. The RRC connection reconfiguration message includes reduced CRS information of the NCT secondary serving cell. The reduced CRS information includes at least one of a reduced CRS period and reduced CRS offset information. For example, if the reduced CRS period is predefined such as sf5 (5 ms), the reduced CRS period information may be omitted. The RRC connection reconfiguration procedure may include a step in which the base station transmits an RRC connection reconfiguration message to the terminal, the terminal configures the NCT secondary serving cell at the terminal, and the base station receives the RRC connection reconfiguration completion message from the terminal. In this case, the BS and the UE can know that the NCT secondary serving cell is configured. For example, the base station may explicitly inform that the newly configured cell is an NCT secondary serving cell. Alternatively, the UE can determine whether the NCT sub-serving cell is configured based on whether information included only in setting the NCT secondary serving cell (for example, reduced CRS information, etc.) is included.

The base station transmits an NCT secondary serving cell activation indicator for activating the added NCT secondary serving cell to the terminal (S2010). The NCT secondary serving cell activation indicator may be transmitted to the UE through a MAC message. The MAC message may include the MAC CE of FIG. 21 described above.

The BS determines whether the value of the DRX configuration duration timer is smaller than the reduced CRS period (S2020). The BS can know the DRX configuration configured in the UE and can know the reduced CRS information of the NCT subserving cell. The base station may compare the duration value of the DRX configuration with the decrease CRS period value. This is true even if the reduced CRS period information is predefined between the UE and the BS with sf5 (5ms).

If the value of the persistent interval timer is smaller than the decrease CRS period in step S2020, DRX reconfiguration is performed according to a predefined criterion between the UE and the BS, and an RRC connection reconfiguration message including the reconfigured DRX- (S2030). Since the base station knows the DRX configuration information of the UE and the reduced CRS information of the NCT secondary serving cell, it can perform DRX reconfiguration at the base station based on the CRS information. In such a case, the BS may not transmit a separate RRC connection reconfiguration message for the DRX reconfiguration procedure to the UE. The DRX reconfiguration at the base station performed at the base station corresponds to the DRX reconfiguration at the terminal at the terminal. That is, the operation of the base station performing the DRX reconfiguration may be performed in the same manner as the operation of performing the DRX reconfiguration in step S1930. For example, the BS may adjust the size of the duration timer of the DRX operation to be equal to or longer than the period of the reduced CRS considering the period of the reduced CRS. That is, if the duration timer is less than the duration of the reduced CRS, the base station may replace the duration timer with a value that is equal to or somewhat larger than the period of the reduced CRS. As another example, the base station may adjust the DRX offset value in consideration of the offset value of the reduced CRS. That is, if the DRX offset is different from the reduced CRS offset, the base station may perform the DRX reconstruction with a value equal to the reduced CRS offset. As another example, the base station may adjust the DRX offset value in consideration of the offset value of the reduced CRS as well as adjust the DRX duration timer in consideration of the period of the reduced CRS. That is, if the DRX duration timer is smaller than the period of the reduced CRS, the base station sets the DRX duration timer to a value equal to or greater than the period of the reduced CRS, and if the DRX offset value is different from the reduced CRS offset value , The DRX offset value may be set to the reduced CRS offset value.

If the value of the persistent interval timer is equal to or less than the decrease CRS period at S2020, the base station may not perform implicit DRX reconfiguration between the UE and the BS.

Although it is shown in FIG. 20 that S2020 and S2030 are performed after S2010, S2020 and S2030 may be performed when the base station receives the RRC connection reconfiguration completion message from the terminal in S2000. In other words, S2020 may be performed regardless of S2010. In this case, when the base station receives the RRC connection reconfiguration complete message from the UE, the BS recognizes that the NCT secondary serving cell is not yet activated but is a spare cell configured and usable in the UE, Lt; RTI ID = 0.0 > DRX < / RTI > reconstruction.

FIG. 21 is a block diagram illustrating a terminal and a base station performing DRX reconfiguration considering an NCT according to an exemplary embodiment of the present invention. Referring to FIG.

21, a terminal 2100 includes a terminal receiving unit 2105, a terminal processor 2110, and a terminal transmitting unit 2120. The terminal processor 2110 includes a message processing unit 2111 and a DRX operation control unit 2112.

 The terminal reception unit 2105 receives the RRC connection reconfiguration message from the base station 2150. The RRC connection reconfiguration message includes the NCT secondary serving cell configuration information and the reduced CRS information of the NCT secondary serving cell. In addition, the terminal receiving unit 2105 receives an NCT secondary serving cell activation indicator from the base station 2150. The UE receiving unit 2105 may receive the NCT secondary serving cell activation indicator through a MAC message.

The message processing unit 2111 analyzes or analyzes the syntax of the information or message received from the terminal receiving unit 2105.

The message processor 2111 may interpret the received RRC connection reconfiguration message and obtain the NCT secondary serving cell configuration information and the reduced CRS information included in the message. For example, the message processing unit 2111 can interpret the syntax of Table 2 described above. The reduced CRS information may include at least one of a reduced CRS period and reduced CRS offset information. For example, if the reduced CRS period is predefined such as sf5 (5ms), the reduced CRS period information may be omitted.

Also, the message processor 2111 can configure the NCT secondary serving cell in the UE based on the NCT secondary serving cell configuration information. The message processor 2111 may generate an RRC connection reconfiguration complete message and transmit the message to the base station 2150 through the terminal transmitter 2120.

Also, the message processor 2111 can interpret the received NCT secondary serving cell activation indicator. For example, the message processing unit 2111 can interpret the LCID of Table 3 and the MAC CE of FIG. 21 described above. Specifically, the message processor 2111 may interpret the MAC message and activate the NCT secondary serving cell indicated by the NCT secondary serving cell activation indicator included in the MAC message.

The DRX operation control unit 2112 configures / reconfigures DRX-related parameters at the terminal 2100. For example, the DRX operation control unit 2112 may configure / reconfigure parameters related to the persistent interval timer and the DRX offset.

The DRX operation control unit 2112 can determine DRX reconfiguration at the terminal 2100 based on the DRX-related parameters configured in the terminal 2100 and the reduced CRS period. The DRX operation controller 2112 can determine DRX reconfiguration at the UE 2100 based on the DRX duration timer value and the reduced CRS period value configured in the UE 2100. [ For example, the DRX operation control unit 2112 can start DRX reconfiguration at the terminal 2100 when the terminal receiving unit 2105 receives the NCT secondary serving cell activation indicator from the BS 2150. In another example, the DRX operation control unit 2112 can start DRX reconfiguration at the terminal 2100 when the message processing unit 2111 configures the NCT secondary serving cell in the terminal. In another example, the DRX operation control unit 2112 can start DRX reconfiguration at the terminal 2100 when the terminal transmission unit 2120 transmits the RRC connection reconfiguration completion message to the base station 2150.

Specifically, the DRX operation controller 2112 can perform DRX reconstruction according to a predefined criterion when the value of the DRX duration timer is smaller (in terms of time) than the reduced CRS period value. For example, the DRX operation controller 2112 may adjust the duration of the DRX operation duration timer to be equal to or longer than the period of the reduced CRS in consideration of the period of the reduced CRS. That is, if the duration timer is less than the period of the reduced CRS, the DRX operation controller 2112 may replace the duration timer with a value that is equal to or somewhat larger than the period of the reduced CRS. As another example, the DRX operation controller 2112 may adjust the DRX offset value in consideration of the reduced CRS offset value. That is, if the DRX offset is different from the reduced CRS offset, the DRX operation controller 2112 can perform the DRX reconstruction with a value equal to the reduced CRS offset. As another example, the DRX operation control unit 2112 may adjust the DRX offset value in consideration of the offset value of the reduced CRS as well as adjust the DRX duration timer in consideration of the period of the reduced CRS. That is, if the DRX duration timer is smaller than the period of the reduced CRS, the DRX operation controller 2112 sets the DRX duration timer to a value equal to or greater than the period of the reduced CRS, If the CRS offset value is different from the CRS offset value, the DRX offset value may be set to the reduced CRS offset value.

The UE transmitter 2120 can transmit the generated RRC connection reconfiguration complete message to the BS 2150.

The base station 2150 includes a base station transmitting unit 2155, a base station receiving unit 2170, and a base station processor 2160. The base station processor 2160 includes a message processing unit 2161 and a DRX operation control unit 2162.

The base station transmitting unit 2155 transmits an RRC connection reconfiguration message to the terminal 2100. The RRC connection reconfiguration message includes at least one NCT partial serving cell configuration information and a reduced CRS information of the NCT secondary serving cell. In addition, the base station transmitting unit 2155 transmits the NCT secondary serving cell activation indicator to the terminal 2100. The base station transmitting unit 2155 may transmit the NCT secondary serving cell activation indicator through a MAC message.

The base station receiving unit 2170 receives the RRC connection reconfiguration completion message from the UE 2100.

The message processor 2161 generates an RRC message or a MAC message. The message processing unit 2161 may generate the RRC connection reconfiguration message including the NCT secondary serving cell configuration information and the reduced CRS information of the NCT secondary serving cell. In this case, the message processing unit 2161 may generate the RRC connection reconfiguration message including, for example, the syntax of Table 2 described above. The reduced CRS information may include at least one of a reduced CRS period and reduced CRS offset information. For example, if the reduced CRS period is predefined such as sf5 (5ms), the reduced CRS period information may be omitted.

In addition, the message processor 2161 may generate a MAC message including the NCT secondary serving cell activation indicator. In this case, the message processor 2161 may generate the MAC message including the MAC CEs of FIGS. 21 and 22, for example.

The DRX operation control unit 2162 configures / reconfigures DRX-related parameters at the base station 2150.

DRX operation controller 2162 can determine DRX reconfiguration at the base station 2150 based on the DRX-related parameters configured in terminal 2100 and the reduced CRS period. The DRX operation control unit 2162 can determine DRX reconfiguration at the UE 2100 based on the DRX duration timer value and the reduced CRS period value configured in the UE 2100. [ For example, the DRX operation control unit 2162 can start DRX reconfiguration at the base station 2150 when the base station transmitting unit 2155 transmits the NCT secondary serving cell activation indicator to the terminal 2100. In another example, the DRX operation control unit 2162 may initiate DRX reconfiguration at the base station 2150 when the base station receiving unit 2470 receives the RRC connection reconfiguration completion message from the terminal 2100.

DRX reconfiguration performed in the DRX operation control unit 2162 corresponds to DRX reconfiguration performed in the DRX operation control unit 2112 of the UE 2100. [ Specifically, the DRX operation control unit 2162 may perform DRX reconstruction according to a predefined criterion when the value of the DRX duration timer is smaller than the reduced CRS period value. For example, the DRX operation controller 2162 may adjust the duration of the DRX operation duration timer to be equal to or longer than the period of the reduced CRS in consideration of the period of the reduced CRS. That is, if the duration timer is less than the duration of the reduced CRS, the DRX operation controller 2162 may replace the duration timer with a value that is equal to or somewhat larger than the period of the reduced CRS. As another example, the DRX operation control unit 2162 may adjust the DRX offset value in consideration of the reduced CRS offset value. That is, if the DRX offset is different from the reduced CRS offset, the DRX operation control unit 2162 can perform the DRX reconstruction with a value equal to the reduced CRS offset. As another example, the DRX operation control unit 2112 may adjust the DRX offset value in consideration of the offset value of the reduced CRS as well as adjust the DRX duration timer in consideration of the period of the reduced CRS. That is, if the DRX duration timer is smaller than the period of the reduced CRS, the DRX operation controller 2112 sets the DRX duration timer to a value equal to or greater than the period of the reduced CRS, If the CRS offset value is different from the CRS offset value, the DRX offset value may be set to the reduced CRS offset value.

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 falling within the scope of the same shall be construed as falling within the scope of the present invention.

Claims (21)

A UE (UE) that performs DRX (Discontinuous Reception) operation considering a NCT (New Carrier Type) in a Multiple Complement Carrier System,
A receiving unit for receiving a Radio Resource Control (RRC) Connection Reconfiguration message including NCT secondary serving cell configuration information and reduced CRS (Reduced CRS) information from a base station (eNB);
A message processor for constructing the NCT secondary serving cell based on the NCT secondary serving cell configuration information and generating an RRC connection reconfiguration complete message;
A transmitting unit for transmitting the generated RRC connection reconfiguration complete message to the base station; And
And a DRX operation controller for performing DRX reconfiguration at the terminal based on the DRX related parameter and the reduced CRS information currently configured in the terminal. The method according to claim 1,
Wherein the reduced CRS information comprises reduced CRS period information and reduced CRS offset information,
Wherein the DRX operation controller performs the DRX reconstruction when a duration timer value of the DRX-related parameters is smaller than a value of the reduced CRS period in terms of time. The method according to claim 1,
Wherein the reduced CRS information includes reduced CRS offset information,
Wherein the DRX operation controller performs the DRX reconfiguration when a duration timer value of the DRX-related parameters is temporally smaller than a predefined reduced CRS period value between the UE and the base station. Terminal. 3. The method of claim 2,
Wherein the DRX operation controller performs the DRX reconfiguration when the message processor configures the NCT secondary serving cell. 3. The method of claim 2,
Wherein the DRX operation controller performs the DRX reconfiguration when the transmitter transmits the RRC connection reconfiguration completion message to the base station. 3. The method of claim 2,
Wherein the receiving unit receives an activation indicator for the NCT secondary serving cell from the base station,
Wherein the DRX operation controller performs the DRX reconfiguration when the receiver receives an activation indicator for the NCT secondary serving cell from the base station. 6. The method of claim 5,
Wherein the DRX operation controller performs the DRX reconfiguration such that at least one of the DRX-related parameters and the DRX offset value matches the reduced CRS period or the reduced CRS offset value. In a multi-element carrier system, a base station that performs DRX operation considering NCT,
A message processing unit for generating an RRC connection reconfiguration message including NCT secondary serving cell configuration information and reduced CRS information;
A transmitting unit for transmitting the generated RRC connection reconfiguration message to a terminal;
A receiver for receiving an RRC connection reconfiguration completion message from the terminal; And
And a DRX operation controller for performing DRX reconfiguration at the base station based on a DRX-related parameter currently configured for the UE and the reduced CRS information. 9. The method of claim 8,
Wherein the reduced CRS information comprises reduced CRS period information and reduced CRS offset information,
Wherein the DRX operation controller performs the DRX reconfiguration when the duration timer value of the DRX-related parameters is smaller than the decrease CRS period value in terms of time. 9. The method of claim 8,
Wherein the reduced CRS information includes reduced CRS offset information,
Wherein the DRX operation controller performs the DRX reconfiguration when a duration timer value of the DRX-related parameters is temporally smaller than a predefined reduced CRS period value between the UE and the base station. 10. The method of claim 9,
Wherein the DRX operation controller performs the DRX reconfiguration when the receiver receives the RRC connection reconfiguration completion message from the UE. 10. The method of claim 9,
The message processing unit generates an activation indicator for the NCT secondary serving cell,
The transmitting unit transmits an activation indicator for the generated NCT secondary serving cell to the terminal,
Wherein the DRX operation controller performs the DRX reconfiguration when the transmitter transmits an activation indicator for the NCT secondary serving cell to the UE. 12. The method of claim 11,
Wherein the DRX operation controller performs the DRX reconstruction so that at least one of the DRX-related parameter and the DRX offset value matches the reduced CRS period or the reduced CRS offset value. In the DRX reconstruction method considering the NCT performed by the UE in the multi-element carrier system,
Receiving from the base station an RRC connection reconfiguration message including NCT secondary serving cell configuration information and reduced CRS information;
Constructing the NCT secondary serving cell based on the NCT secondary serving cell configuration information;
Generating an RRC connection reconfiguration completion message indicating that the UE has completed RRC connection reconfiguration based on the RRC connection reconfiguration message;
Transmitting the generated RRC connection reconfiguration complete message to the BS; And
And performing DRX reconfiguration at the terminal based on the DRX-related parameter and the reduced CRS information currently configured in the terminal. 15. The method of claim 14,
Wherein the reduced CRS information comprises reduced CRS period information and reduced CRS offset information,
Wherein the DRX reconfiguration is performed when a duration timer value of the DRX-related parameters is temporally smaller than the reduced CRS period value. 16. The method of claim 15,
Wherein the DRX reconfiguration is performed when the transmitting unit transmits the RRC connection reconfiguration completion message to the BS. 17. The method of claim 16,
Wherein the DRX reconstruction is performed such that at least one of the DRX-related parameter and the DRX offset value matches the reduced CRS period or the reduced CRS offset value. In the DRX reconstruction method considering the NCT performed by the base station in the multi-element carrier system,
Generating an RRC connection reconfiguration message including NCT secondary serving cell configuration information and reduced CRS information;
Transmitting the generated RRC connection reconfiguration message to a terminal;
Receiving an RRC connection reconfiguration completion message from the terminal; And
And performing DRX reconfiguration at the base station based on the DRX-related parameters currently configured for the UE and the reduced CRS information. 19. The method of claim 18,
Wherein the reduced CRS information comprises reduced CRS period information and reduced CRS offset information,
Wherein the DRX reconfiguration is performed when a DRX-related parameter of the DRX-related parameters is temporally smaller than the reduced CRS period value. 20. The method of claim 19,
Wherein the DRX reconfiguration is performed when the receiving unit receives the RRC connection reconfiguration completion message from the UE. 21. The method of claim 20,
Wherein the DRX reconstruction is performed such that at least one of the DRX-related parameter and the DRX-related parameter satisfies the reduced CRS period or the reduced CRS offset value.

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