KR20140040544A - Method and apparatus of stopping and resuming uplink transmission in multiple component carrier system - Google Patents

Abstract

The present invention relates to a method and an apparatus for stopping and resuming uplink transmission in a multi-component carrier system, wherein the method comprises the steps of: receiving, from a base station, a medium access control (MAC) message including an uplink transmission stopping instructor for instructing a terminal to stop transmitting uplink; and setting a state of a serving cell as an uplink transmission stopping state based on the uplink transmission stopping instructor, wherein the serving cell is an instruction target of the uplink transmission stopping instructor, is included in a specific time alignment group or is included in all the terminals. According to the present invention, a base station can block unnecessary uplink transmission in a terminal, thereby reducing consumption of a battery in the terminal. [Reference numerals] (AA) Terminal; (BB) Base station; (S500) RRC connection setup procedure; (S505) Sub-serving cell configuration procedure (Performed in a main serving cell); (S510) Activation instructor; (S515) Uplink transmission stopping instructor; (S520) Uplink transmission resuming instructor

Description

METHOD AND APPARATUS OF STOPPING AND RESUMING UPLINK TRANSMISSION IN MULTIPLE COMPONENT CARRIER SYSTEM}

The present invention relates to wireless communication, and more particularly, to a method and apparatus for stopping and resuming uplink transmission in a multi-component 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 such a single carrier system, wireless communication is performed using one carrier. However, with the recent introduction of multiple component carrier systems, wireless communication can be implemented through multiple component carriers.

On the other hand, since the battery of the terminal is limited, power saving should be considered. Recently, due to the popularization of various mobile devices such as smartphones or tablets, the interest in power saving of the terminal is increasing. As a method for saving power of the terminal, there is a DRX (Discontinuous Reception) scheme in which power is saved by dividing the terminal into an active time and an inactive time. However, in the DRX method, only downlink reception of the UE is periodically controlled and performed on a per-unit basis. On the other hand, in the case of uplink, since the terminal directly generates and transmits a radio signal, power consumption is larger than that of receiving downlink signals. Therefore, power saving methods such as DRX are limited. Accordingly, there is a need for a method capable of adaptively controlling uplink transmission through a component carrier in a component carrier system using a plurality of component carriers for communication.

An object of the present invention is to provide a method and apparatus for adaptively controlling uplink transmission in a wireless communication system.

Another object of the present invention is to provide a method and apparatus for performing uplink transmission stop and resume.

Another technical problem of the present invention is to provide a method and apparatus for performing uplink transmission interruption and resumption without affecting downlink transmission performance.

Another technical problem of the present invention is to provide a method and apparatus for performing interruption and resumption of uplink transmission on a terminal, time alignment group, or serving cell basis.

Another technical problem of the present invention is to perform uplink transmission interruption and resumption based on a medium access control (MAC) message indicating the uplink transmission suspension and resumption.

According to an aspect of the present invention, a method for controlling uplink transmission by a terminal in a multi-component carrier system is provided. The method includes receiving a medium access control (MAC) message including an uplink transmission stop indicator indicating an uplink transmission stop indicator of a serving cell configured in the terminal from the base station, and instructing the uplink transmission stop indicator And setting a state of the serving cell configured in the terminal to an uplink transmission stop state.

According to another aspect of the present invention, there is provided a method for controlling uplink transmission by a base station in a multi-component carrier system. The method includes determining an uplink transmission stop of a serving cell configured in a terminal, generating a MAC message including an uplink transmission stop indicator indicating an uplink transmission stop of a serving cell configured in the terminal, and the MAC And transmitting the message to the terminal.

According to another aspect of the present invention, a terminal for controlling uplink transmission in a multi-component carrier system is provided. The terminal obtains a terminal RF unit for receiving a MAC message including an uplink transmission stop indicator indicating an uplink transmission stop of a serving cell configured in the terminal from a base station, and the uplink transmission stop indicator based on the MAC message. And an uplink transmission control unit configured to set a state of the serving cell configured in the terminal to an uplink transmission stop state based on the MAC message processing unit and the uplink transmission stop indicator.

According to another aspect of the present invention, there is provided a base station for performing uplink transmission control in a multi-component carrier system. The base station generates a MAC message including an uplink transmission determination unit for determining whether to stop the uplink transmission of the serving cell configured in the terminal, and an uplink transmission stop indicator for instructing the uplink transmission stop of the serving cell configured in the terminal. MAC message processing unit, and the base station RF unit for transmitting the MAC message to the terminal.

According to the present invention, it is possible to adaptively control uplink transmission through the component carrier in a multi-component carrier system.

According to the present invention, uplink transmission can be interrupted and resumed in units of terminals, in units of time alignment groups, or in units of serving cells.

According to the present invention, the base station can block unnecessary uplink transmission of the terminal and can reduce battery consumption of the terminal.

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.
5 is a flowchart illustrating a method of stopping and resuming uplink transmission according to an embodiment of the present invention.
6 shows a structure of a MAC message according to an embodiment of the present invention.
7 is a block diagram illustrating a structure of a MAC subheader according to an embodiment of the present invention.
8 is a block diagram illustrating a structure of a MAC subheader according to another embodiment of the present invention.
9 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.
10 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.
11 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.
12 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.
13 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.
14 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.
15 is a flowchart illustrating a method of interrupting and resuming uplink transmission of a terminal according to an embodiment of the present invention.
16 is a flowchart illustrating a method of interrupting and resuming uplink transmission of a base station according to an embodiment of the present invention.
FIG. 17 is a block diagram illustrating a terminal and a base station performing interruption and resumption of uplink transmission according to an example of the present invention.

Hereinafter, some embodiments 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 functions and configurations incorporated herein will be omitted when it may make the subject matter of the present disclosure rather unclear.

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 (BS) 11 and a repeater (not shown). 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 (MT), a user 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 must be interpreted in a comprehensive meaning to indicate a partial area covered by the base station 11 and includes all the coverage areas such as a megacell, a macrocell, a microcell, a picocell, a femtocell, and a small cell to be.

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.

Carrier aggregation (CA) supports a plurality of carriers, also referred to as spectrum aggregation or bandwidth aggregation. Individual unit carriers bound by carrier aggregation are called component carriers (CCs). Each element carrier is defined as the bandwidth and center frequency. Carrier aggregation is introduced to support increased throughput, prevent cost increases 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 supporting carrier aggregation. 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 several physical control channels used in the physical layer 220. The physical downlink control channel (PDCCH) informs the UE of resource allocation of a paging channel (PCH) and downlink shared channel (DL-SCH) and hybrid automatic repeat request (HARQ) information related to the DL-SCH. The PDCCH may carry an uplink grant informing the UE of the resource allocation of the uplink transmission. A physical control format indicator channel (PCFICH) informs the UE of the number of OFDM symbols used for PDCCHs and is transmitted every subframe. PHICH (physical Hybrid ARQ Indicator Channel) carries a HARQ ACK / NAK signal in response to uplink transmission. A physical uplink control channel (PUCCH) carries uplink control information such as HARQ ACK / NAK, scheduling request and CQI for downlink transmission. 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, a frame includes 10 subframes. The subframe includes a plurality of OFDM symbols. Each component carrier may have its own control channel (eg, PDCCH). The multi-element carriers may or may not be adjacent to each other. The terminal may support one or more carriers according to its capabilities.

The component carrier may be divided into a primary component carrier (PCC) and a secondary component carrier (SCC) according to activation. The major carriers are always active carriers, and the subcarrier carriers are carriers that are activated / deactivated according to specific conditions. Activation means that the transmission or reception of traffic data is performed or is in a ready state. Deactivation means that transmission or reception of traffic data is impossible and measurement or transmission / reception of minimum information is possible. 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.

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, in the downlink, for example, the downlink component carriers D1, D2, and D3 are aggregated 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). The indexes do not coincide with the order of the element carriers or the positions of the frequency bands of the corresponding element carriers.

On the other hand, at least one downlink component carrier may be a main carrier and the remainder may be a sub-carrier. Also, at least one uplink component carrier may be a dominant carrier and the remainder may be 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. The elementary carrier index can be expressed as a serving cell index and can be defined by dividing the serving cell index including the main serving cell and the secondary serving cell index for only the secondary serving cells.

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.

Here, the downlink component carrier and the uplink component carrier can be established in a 1: 1 connection as well as a 1: n or n: 1 connection.

A primary serving cell is a serving cell that provides security input and NAS mobility information in an 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, a UE transmits a preamble using UL CC is equivalent to transmitting a preamble using a main serving cell or a secondary serving cell. In addition, receiving a downlink information using a DL CC by a UE can be regarded as equivalent to receiving downlink information using a main serving cell or a secondary serving cell.

On the other hand, the main serving cell and the secondary serving cell have the following characteristics.

First, the main serving cell is used for transmission of the PUCCH. On the other hand, the secondary serving cell can not transmit the PUCCH but may transmit some of the information in the PUCCH through the PUSCH.

Second, the main serving cell is always activated, while the secondary serving cell is a carrier that is activated / deactivated according to a specific condition. The specific condition may be a case where the activation / deactivation MAC control element message of the base station is received or the deactivation timer configured for each secondary serving cell in the terminal expires.

Third, when the primary serving cell experiences RLF, RRC reconnection is triggered, but when the secondary serving cell experiences RLF, RRC reconnection is not triggered. Or, do not define RLF for secondary serving cell. The radio link failure occurs when downlink performance is maintained below a threshold for a predetermined time or when a random access procedure through the main serving cell fails more than a threshold. If the random access procedure through the secondary serving cell fails more than the threshold number of times, only the corresponding random access procedure is terminated.

Fourth, the main serving cell may be changed by a security key change or a handover procedure accompanying a random access procedure. However, in the case of a content resolution (CR) message, only a downlink control channel (hereinafter referred to as 'PDCCH') indicating a CR should be transmitted through the main serving cell, and the CR information may be transmitted through the main serving cell or the secondary serving cell. It can be transmitted through.

Fifth, non-access stratum (NAS) information is received through the main serving cell.

Sixth, the main serving cell always consists of DL PCC and UL PCC in pairs.

Seventh, a different CC may be set as a primary serving cell for each terminal.

Eighth, procedures such as reconfiguration, adding, and removal of the secondary serving cell may be performed by the radio resource control (RRC) layer. In addition to the new secondary serving cell, RRC signaling may be used to transmit the system information of the dedicated secondary serving cell.

Ninth, the main serving cell transmits PDCCH (e.g., downlink allocation information) assigned to a UE-specific search space set for transmitting control information for a specific UE in a region for transmitting control information Or PDCCH (e.g., system information (e.g., uplink information) allocated to a common search space set for transmitting control information to all terminals in the cell or to a plurality of terminals conforming to a specific condition, SI), a random access response (RAR), and transmit power control (TPC). On the other hand, only the UE-specific search space can be set as the serving cell. That is, since the UE can not confirm the common search space through the secondary serving cell, it can not receive the control information transmitted only through the common search space and the data information indicated by the control information.

The technical idea of the present invention regarding the characteristics of the main serving cell and the secondary serving cell is not necessarily limited to the above description, but is merely an example and may include more examples.

In a wireless communication system, synchronization between a base station and a terminal must be made in advance in order to receive an information signal regardless of downlink and uplink. Types of synchronization include frame synchronization, information symbol synchronization, and sampling period synchronization. Sampling period synchronization is the most basic motivation to distinguish physical signals.

Downlink synchronization acquisition is performed in the terminal based on the signal transmitted from the base station. The base station transmits a mutually agreed specific signal for facilitating downlink synchronization acquisition at the terminal. The terminal must be able to accurately identify the time at which a particular signal sent from the base station is transmitted. In case of downlink, since one base station simultaneously transmits the same synchronization signal to a plurality of terminals, each of the terminals can acquire synchronization independently of each other.

In case of uplink, the base station receives signals transmitted from a plurality of terminals. When the distance between each terminal and the base station is different, the signals received by the base station have a different transmission delay time. When transmitting uplink information based on downlink synchronization acquired by each terminal, the base station receives information of each terminal at different times. In this case, the base station can not acquire synchronization based on any one of the terminals. Therefore, uplink synchronization acquisition requires a procedure different from downlink.

A random access procedure may be performed for uplink synchronization acquisition. The random access procedure may be divided into a contention based random access procedure and a non-contention based random access procedure. The biggest difference between the contention-based random access procedure and the non- contention-based random access procedure is whether a random access preamble is designated as dedicated to one UE. In the non-contention based random access procedure, since the terminal uses a dedicated random access preamble designated only for itself, contention (or collision) with other terminals does not occur. Here, contention means that two or more terminals competitively use a time / frequency / sequence resource set to access a base station so that the base station can use the plurality of terminals without allocating them to each terminal. In the contention-based random access procedure, since a terminal uses a randomly selected time / frequency resource and a random access preamble, there is a possibility of contention with another terminal other than the terminal. The time-frequency resource at which the random access preamble is transmitted from the terminal to the base station is a PRACH. That is, the random access preamble is transmitted from the terminal to the base station through the PRACH. In the contention-based random access procedure, the UE randomly transmitting the random access preamble to the base station through the PRACH may be referred to as PRACH transmission by the UE's selection. In the non-contention based random access procedure, the UE may randomly access the random access procedure from the base station through the PDCCH. Receiving a PDCCH order indicating the start of the transmission and transmitting the dedicated random access preamble to the base station through the PRACH may be referred to as PRACH transmission according to the indication of the base station.

During the random access procedure, the UE adjusts uplink synchronization by adjusting an uplink time based on a value or a timing alignment value in a timing advance command field included in a random access response provided by the base station. Acquire. The time alignment value is information for quantitatively indicating a time to be adjusted for uplink synchronization in a specific secondary serving cell based on a downlink synchronization time of a timing reference cell when a random access attempt of a corresponding UE is performed. If a predetermined time elapses after acquiring uplink synchronization based on the time alignment value, the obtained uplink synchronization may not be valid due to a change in an external radio channel such as a movement of a terminal. Therefore, the UE is configurable by the base station to determine whether the obtained uplink synchronization is valid, and upon expiration, a time alignment timer (TAT) may be used to start a random access procedure by the terminal for obtaining uplink synchronization. ) Is configured. When the time alignment timer is in operation, the terminal determines that the terminal and the base station are in synchronization with each other. If the time alignment timer expires or does not operate, the terminal and the base station are not synchronized with each other, the terminal does not perform any uplink transmission other than the transmission of the random access preamble.

In a multi-component carrier system, one terminal communicates with a base station through a plurality of component carriers or a plurality of serving cells. If the signals transmitted from the terminal to the base station through the plurality of serving cells all have the same time delay, the terminal can obtain uplink synchronization for all the serving cells with one time alignment value. On the other hand, if the signals transmitted to the base station through the plurality of serving cells have different time delays, different time alignment values are required for each serving cell. That is, multiple timing alignment values are required. The multiple time alignment value may be referred to as a multiple timing advance value. If the UE performs a random access procedure for each serving cell in order to obtain multi-time alignment values, an overhead occurs in limited uplink and downlink resources since the number of random access procedures required for uplink synchronization is increased. In addition, the complexity of the synchronization tracking procedure for maintaining uplink synchronization may increase. A timing alignment group (TAG) is defined to reduce this overhead and complexity. The time alignment group may be referred to as a timing advance group.

The TAG is a group including serving cell (s) using the same time forward value and the same timing reference or the timing reference cell including the timing reference among the serving cells configured with the UL CC. Here, the timing reference is a DL CC which is a reference for calculating the time forward value. For example, when the first serving cell and the second serving cell belong to TAG1 and the second serving cell is a timing reference cell, the same time forward value TA1 is applied to the first serving cell and the second serving cell, and the first serving cell. The TA1 value is applied based on the downlink synchronization time of the DL CC of the second serving cell. On the other hand, when the first serving cell and the second serving cell belong to TAG1 and TAG2, respectively, the first serving cell and the second serving cell become timing reference cells in the corresponding TAG, respectively, and have different times for the first serving cell and the second serving cell. Forward values TA1 and TA2 apply respectively. The TAG may include a main serving cell, may include at least one secondary serving cell, and may include a primary serving cell and at least one secondary serving cell.

Each TAG includes at least one serving cell configured with a UL CC, and information on the serving cell mapped to each TAG is called TAG configuration information. The TAG is transmitted to the UE through RRC signaling when the initial group configuration and group reconfiguration are determined by the serving base station configuring the serving cell.

The main serving cell does not change the TAG. In addition, the terminal should be able to support at least two TAG when a multi-time forward value is required. For example, it should be able to support pTAG (primary TAG) including main serving cell and TAG separated by sTAG (secondary TAG) without main serving cell. Here, only one pTAG may exist at any time, and at least one sTAG may exist if a multi-time forward value is required. That is, if multiple time advance values are required, a plurality of TAGs may be set.

In order for the UE to transmit an uplink signal excluding the random access preamble, the UE must obtain a valid time alignment value for the UL CC corresponding to the corresponding serving cell. If a valid time alignment value for the UL CC is secured, the terminal may be configured with a sounding reference signal (SRS) or channel state information (CSI) previously configured by the base station on the UL CC. The uplink signal may be periodically transmitted without a special indication of the base station. In addition, a signal such as aperiodic SRS indicated by the base station and a data channel such as PUSCH may also be transmitted. Here, the SRS may be a basic reference signal for measuring uplink synchronization in order for the base station to update a time alignment value. Here, the SRS periodically transmitted without the special indication of the base station may be called a type-0 SRS, and the aperiodic SRS indicated by the base station may be called a type-1 SRS. Meanwhile, data or various uplink control information as well as sounding reference signals are transmitted through the uplink control channel. The uplink control signal includes an ACK (ACKnowledgement) / NACK (Not-ACKnowledgement) signal for performing HARQ (Hybrid Automatic Repeat reQuest), a channel quality indicator (CQI) indicating downlink channel quality, a precoding matrix index (PMI), There are various types such as RI (Rank Indicator).

In relation to activation of a serving cell configured in a terminal in a multi-component carrier system, only uplink or only downlink cannot be individually activated. That is, even when the serving cell is activated only for downlink transmission, uplink transmission may be performed unnecessarily. For example, the CSI and the type-0 SRS described above are periodically transmitted through the uplink only for the active serving cells without special indication when the uplink resource for periodic transmission is configured by the base station. This is true even if the serving cell is activated for uplink transmission and downlink transmission, and in some cases, uplink transmission is no longer necessary. Uplink transmission causes power consumption in a transmission circuit of the terminal, and the power consumption due to the unnecessary uplink transmission described above is not negligible, so that the uplink transmission can be adaptively controlled to reduce the power consumption of the terminal. How to do this is required.

In order to adaptively control the uplink transmission of the terminal, the base station may use a method of transmitting a signal for expiring or stopping the time alignment timer to the terminal. If the time alignment timer expires or does not operate, the terminal and the base station are not synchronized with each other, the terminal does not perform any uplink transmission other than the transmission of the random access preamble. However, in this case, uplink transmission can be interrupted only in a timing alignment group (TAG) unit having the same time alignment value. In addition, when the main serving cell is included in the time alignment group to which the secondary serving cells needing to be suspended, the corresponding TAG is a pTAG (Primary timing alignment group). It is not possible to stop the uplink transmission of the secondary serving cells that need to stop the link transmission. Because, when the time alignment timer of the pTAG expires or stops, the main serving cell that is not the target of uplink transmission is also stopped, and when at least one sTAG other than the pTAG is present, the time alignment timer in all sTAGs also expires or stops. In addition, when the time alignment timer expires or stops, since all uplink transmissions except the PRACH are stopped in the serving cell in the time alignment group, there is a problem that even type-1 SRS transmission indicated by the base station cannot be performed.

Hereinafter, the present invention proposes a method of stopping uplink transmission without having the above problems. To this end, a detailed definition of uplink transmission interruption and a signaling structure transmitted by the base station to the user equipment for interrupting and resuming uplink transmission will be described.

First, the definition of the uplink transmission stop is as follows.

1. When the target of the uplink transmission is the main serving cell (PCell), one of the following four cases includes the target to stop of the signaling or data channels that can be transmitted uplink.

(1) All uplink transmissions except PRACH transmissions according to the indication of the base station are stopped. That is, PRACH transmission by the selection of the UE is stopped, PUCCH and PUSCH transmission are stopped, and type-0 SRS and type-1 SRS transmission are stopped. In this case, however, the PRACH transmission under the indication of the base station is allowed because of high importance.

(2) Uplink transmission of data and control information with low importance is stopped. That is, transmission of PUSCH and transmission of low importance PUCCH are stopped, and type-0 SRS and type-1 SRS transmission of low importance are also stopped. In this case, however, the CSI information and the ACK / NACK signal transmission by the BS are exceptionally allowed.

(3) SRS transmission is stopped. That is, Type-0 SRS and Type-1 SRS transmissions are stopped.

(4) PUSCH transmission and transmission of low importance PUCCH are stopped and type-0 SRS transmission is stopped.

(5) Only type-0 SRS stops transmitting.

2. When the target of the uplink transmission stop is a secondary cell (SCell), one of the following six cases includes the target to be stopped among the signaling or data channels capable of uplink transmission.

(1) All uplink transmissions except PRACH transmissions according to the indication of the base station are stopped. That is, all PUSCH transmissions are stopped, and type-0 SRS and type-1 SRS transmissions are stopped. However, even in this case, PRACH transmission by the BS instruction is allowed. Since the PUCCH is transmitted through the main serving cell, it is not included in the uplink transmission stop target.

(2) All uplink transmissions except PRACH transmission and type-1 SRS transmission according to the indication of the base station are stopped. That is, all PUSCH transmissions are stopped and type-0 SRS transmissions are stopped. However, even in this case, PRACH transmission and Type-1 SRS transmission according to the indication of the base station are allowed.

(3) PUSCH transmission is stopped, and type-0 SRS transmission is stopped. However, when simultaneous transmission for PUCCH and PUSCH is configured in the UE, periodic CSI information transmission (periodic CSI reporting) may be performed through PUSCH, in which case PUSCH transmission is allowed. In addition, PRACH transmission and Type-1 SRS transmission by the indication of the base station are allowed, CSI information transmission (periodic CSI reporting) by the indication of the base station is allowed, and PUSCH transmission including the ACK / NACK signal is allowed.

(4) PUSCH transmission is stopped, and type-0 SRS and type-1 SRS transmission are stopped. However, when the UE is configured for simultaneous transmission for PUCCH and PUSCH, periodic CSI information transmission (periodic CSI reporting) may be performed through PUSCH, in which case PUSCH transmission is allowed. In addition, PRACH transmission by the indication of the base station is allowed, CSI information transmission (periodic CSI report) and PUSCH transmission including the ACK / NACK signal by the indication of the base station are allowed.

(5) SRS transmission is stopped. That is, Type-0 SRS and Type-1 SRS transmissions are stopped.

(6) Only type-0 SRS stops transmitting.

In order to stop the uplink transmission and resume the uplink transmission of the terminal defined as described above, the base station may signal the terminal based on a MAC message including at least one of an uplink transmission stop indicator and an uplink transmission resume indicator.

5 is a flowchart illustrating a method of stopping and resuming uplink transmission according to an embodiment of the present invention.

Referring to FIG. 5, the terminal performs an RRC connection establishment procedure with the base station (S500). The RRC connection setup procedure includes a terminal transmitting an RRC connection request message to a base station, a base station transmitting an RRC connection setup message to a terminal, and a terminal transmitting an RRC connection setup complete message to a base station. The purpose of the RRC connection establishment procedure is to establish an RRC connection. RRC connection setup includes setup of signaling radio bearer (SRB) 1.

The base station performs a secondary serving cell configuration procedure for additionally configuring at least one secondary serving cell to the terminal (S505). The secondary serving cell configuration procedure may be performed through an RRC connection reconfiguration procedure. The RRC connection reconfiguration procedure includes a base station transmitting an RRC connection reconfiguration message to a terminal and a terminal transmitting an RRC reconfiguration complete message to the base station. The RRC connection reconfiguration message may include a secondary serving cell configuration information field including information on the configuration of the secondary serving cell added to the terminal. Both the RRC connection reconfiguration message and the RRC connection reconfiguration complete message are transmitted and received on the main serving cell. The secondary serving cell configuration procedure may be performed when the base station receives a request for more radio resources from the terminal or the network, or when the base station itself determines that more radio resources are needed.

At least one secondary serving cell additionally configured in the terminal may be classified into the same time alignment group as the main serving cell or may be classified into an independent time alignment group. In the case of being classified as an independent time alignment group, the base station does not have clear information about which time alignment group including at least one secondary serving cell configured in the terminal belongs to the pTAG.

The base station transmits a MAC message including an activation indicator for activating some or all of the secondary serving cells configured in the terminal (S510). The MAC message may be called a MAC protocol data unit (PDU). The MAC message includes at least one medium access control element (MAC CE), and the MAC CE includes an activation indicator. As the base station activates some or all of the secondary serving cells, the base station may allocate resources for secondary serving cells configured in the terminal.

Thereafter, the terminal may configure a timing reference serving cell in each time alignment group. Here, the information about the timing reference cell may or may not be included in the time alignment group configuration information. The timing reference serving cell may be a component carrier unit rather than a serving cell unit. In this case, the downlink timing reference serving cell may be referred to as a downlink timing reference component carrier. In addition, the timing reference component carrier may be designated by being divided into a downlink component carrier or an uplink component carrier. Accordingly, the terminal may apply the time alignment value provided from the base station to each time alignment group. The timing reference serving cell may be used as a representative serving cell for performing a random access procedure between the terminal and the base station.

As an example, if information on a timing reference serving cell is not included in the time alignment group configuration information, the representative serving cell indicates a random access procedure for the base station to obtain an initial uplink time alignment value for the corresponding sTAG. It can also be defined as a cell. As another example, the UE may arbitrarily set and change a timing reference serving cell among serving cells in each sTAG. However, the timing reference serving cell configured by the terminal is not changed unless there is a special reason such as not being able to function as the timing reference serving cell. If the time alignment timer in any sTAG expires and the time alignment value becomes invalid, the representative serving cell setting may be released.

The timing reference serving cell may have the following characteristics. i) There is one timing reference serving cell for each time alignment group. ii) The timing reference serving cell in pTAG is the primary serving cell. iii) The timing reference serving cell in the sTAG may be set only in the serving cell in the corresponding sTAG. iv) In the case of sTAG, the timing reference serving cell may be changed.

In addition, the terminal may perform a random access procedure for obtaining a time alignment value. The UE may obtain a valid time alignment value through a random access procedure based on the downlink timing of the timing reference serving cell in each time alignment group. The random access procedure for acquiring the time alignment value of the sTAG for which a newly configured or valid time alignment value is not obtained is initiated by the command of the base station. That is, the random access procedure for securing the time alignment value of the sTAG for which a newly configured or valid time alignment value is not obtained is a contention-based random access procedure. Accordingly, in this case, the UE may receive a random access initiation indicator indicating a start of a random access procedure for a specific serving cell from the base station on the primary serving cell through a PDCCH order.

As another method for obtaining a time alignment value, the UE may receive a time advance command MAC CE for a sTAG from a base station that has not been newly configured or has a valid time alignment value. Here, the newly configured sTAG is set to a value of '0' as the initial time alignment value, and stores the most recently obtained time alignment value in the case of sTAG which does not have a valid time alignment value. When the terminal receives the time advance command MAC CE, the UE refers to the TAG information included in the time advance command MAC CE based on a timing reference cell and assigns a time alignment value to the corresponding TAG based on the time alignment value secured by each TAG. Apply. That is, the time alignment value received through the time advance command MAC CE is added to the time alignment value secured by each TAG.

The base station transmits an uplink transmission stop indicator indicating to stop the uplink transmission of some or all of the serving cells configured in the terminal, that is, the main serving cell and the secondary serving cells to the terminal (S515). The uplink transmission stop indicator may be included in the MAC message and transmitted to the terminal. Alternatively, the uplink transmission stop indicator may be included in the MAC CE in the MAC message and transmitted to the terminal. In this case, the MAC CE including the uplink transmission stop indicator may include a MAC CE for uplink interrupt, which will be described later, or a MAC CE for uplink transmission / disable. The terminal may reduce unnecessary power consumption by stopping uplink transmission of some or all of the serving cells (main serving cell and secondary serving cells) based on the uplink stop indicator. The uplink transmission interruption may be performed in a cell unit, a TAG unit, or a terminal unit.

If the terminal receives an uplink transmission stop indicator and uplink transmission stop of some or all of the serving cells is set, an operation related to a power headroom report (PHR) even if the serving cell is configured to stop uplink transmission May be the same as other activated serving cells. The surplus power (PH: power headroom) means power that can be additionally used in addition to the power currently used by the UE for uplink transmission, and the surplus power report reports the surplus power to the base station so that the base station is within the surplus power range. This means that scheduling is possible. Through the surplus power reporting procedure, 1) information on the difference between the maximum transmit power of the terminal and the estimated UL-SCH (PUSCH) transmit power for each activated serving cell, and 2) the scheduled serving cell. Information on the difference between the maximum transmission power of the terminal and the predicted PUCCH transmission power, or 3) information on the difference between the maximum transmission power scheduled in the main serving cell and the predicted UL-SCH (PUSCH) and PUCCH transmission power to the serving base station. Can be sent. The surplus power report is transmitted in a MAC message, specifically, included in the MAC CE, wherein the MAC CE includes a V field, where V is a surplus power report based on actual transmission or a surplus power report based on a reference (or virtual) format. To indicate. For example, for Type 1 surplus power, V = 0 indicates actual transmission on the PUSCH, and V = 1 indicates that a PUSCH reference format is used. When UL transmission is stopped and UL-SCH (PUSCH) is not transmitted in the serving cell, a virtual surplus power value that is reported by the corresponding serving cell can always be set. That is, V = 1 may be set. Alternatively, the serving cell may be excluded from the surplus power report. Specifically, in the 8-bit serving cell indicator included in the first octet in the surplus power report MAC CE, the bit corresponding to the position of the serving cell is set to '0' and includes the surplus power report value of the serving cell. I never do that.

In addition, even if the uplink transmission stop is set, the time alignment timer may not be stopped or expired and may be ongoing (ongoing). In addition, even if uplink transmission interruption is set, there is no SRS configuration release information for releasing type-0 SRS and type-1 SRS configuration. In addition, when uplink transmission interruption is configured, the UE may flush all data stored in an uplink hybrid automatic repeat request (HARQ) buffer for the serving cell in which the uplink interruption is configured. In addition, even if uplink transmission interruption is set, the PRACH transmission of the UE according to the indication of the base station is not affected. That is, even if uplink transmission stop is set, the terminal may perform PRACH transmission according to an indication of the base station, unlike deactivation of the serving cell. In addition, when the serving cell in which uplink transmission stop is set is a timing reference cell of the corresponding TAG, the UE may change the serving cell in which the uplink transmission stop is not configured among the serving cells configured in the corresponding TAG into a timing reference cell. In addition, when the target of the uplink transmission stop (stop) is a deactivated serving cell, the terminal may ignore the indication. In addition, when a transmission indicator of the base station is received for uplink signaling or a data channel for which transmission is not allowed by the uplink interrupt definition, the terminal may ignore the indication.

Although FIG. 5 shows that S515 is performed after S510, it may also be performed simultaneously with S510. That is, the uplink transmission stop indicator may be included in the MAC message including the activation indicator in S510 and transmitted to the terminal. In this case, the terminal may first perform an activation / deactivation operation for each secondary serving cell and then perform an operation for a target of uplink transmission stop.

The base station transmits an uplink transmission resumption indicator to the terminal indicating that the uplink transmission of some or all of the serving cells in which the uplink transmission is stopped (S520). Here, resuming uplink transmission means relieving the uplink transmission interruption described above and returning to a state capable of performing uplink transmission. In the present invention, the term "resume" may include restart. The uplink transmission resume indicator may be transmitted in a MAC message. Alternatively, the uplink transmission resume indicator may be included in the MAC CE in the MAC message and transmitted. In this case, the MAC CE including the uplink transmission stop indicator may include a MAC CE for resuming uplink or a MAC CE for uplink transmission / disable. The terminal may resume uplink transmission of some or all of the serving cells in which uplink transmission has been stopped based on the uplink resume indicator, and perform uplink transmission through the corresponding serving cell. Resuming uplink transmission may also be performed in units of cells, TAGs, and terminals as in the case of stopping uplink transmissions. However, if the target of the uplink transmission resume (resume) is a deactivated serving cell, the terminal may ignore the indication.

6 shows a structure of a MAC message according to an embodiment of the present invention.

6, a MAC message 600 includes a MAC header 610, at least one MAC CE 620, ..., 625, at least one MAC Service Data Unit (SDU) (630-1, ..., 630-m) and padding (640).

The MAC header 610 includes at least one subheader 610-1, 610-2,..., 610-k, each subheader 610-1, 610-2 ... .610-k corresponds to one MAC SDU or one MAC CE 620,... 625 or padding 640. The order of the subheaders 610-1, 610-2,..., 610-k may correspond to the corresponding MAC SDU, MAC CE 620,..., 625 or padding 640 in the MAC message 600. They are arranged in the same order.

Each subheader 610-1, 610-2, ..., 610-k includes four fields such as R, R, E, LCID, or three fields such as TAG ID, E, LCID, or It can include four fields: R, F, E, LCID. Alternatively, each subheader 610-1, 610-2,..., 610-k may include six fields such as R, R, E, LCID, F, and L. Subheaders containing three or four fields are subheaders corresponding to MAC control elements 620, ..., 625 or padding 640, and subheaders containing six fields correspond to MAC SDUs. Subheader.

The Logical Channel ID (LCID) field is an identification field for identifying a logical channel corresponding to a MAC SDU, or for identifying a MAC CE (620, ..., 625) or a type of padding. When the headers 610-1, 610-2,..., 610-k have an octet structure, the LCID field may be 5 bits.

For example, as shown in Table 1, the LCID field may identify whether the corresponding MAC CE (620, ..., 625) is a MAC CE (hereinafter referred to as MAC CE for downlink transmission interruption) for indicating an uplink transmission interruption. Can be.

Index (Index) LCID value (value) 00000 CCCH 00001-01010 Identity of the logical channel 01011-11001 Reserved 11010 UL transmission stop 11011 Activation / Deactivation 11100 UE Contention Resolution Identity 11101 Timing Advance Command 11110 The DRX command (DRX command) 11111 Padding

Referring to Table 1, if the index of the LCID field is 11010, the corresponding MAC CE is a MAC CE for stopping uplink transmission. For example, the MAC CE for stopping uplink transmission may have a size of 8 bits or more, or may have a size of zero bits. Based on the MAC CE regarding the uplink transmission interruption, the terminal may identify (or determine) a target of the uplink transmission interruption in a serving cell unit, a time alignment group unit, or a terminal unit. For example, if the MAC CE for the uplink transmission interruption has a zero bit size, the terminal may know that the target of the uplink transmission interruption is the terminal unit, and in this case, the uplink transmission for all secondary serving cells is stopped. . As another example, uplink transmission for the main serving cell may be stopped along with all secondary serving cells. The detailed definition of the uplink transmission interruption is as described above.

Or, as shown in Table 2, the LCID field indicates whether the corresponding MAC CE (620, ..., 625) is the MAC CE for stopping the uplink transmission, or MAC CE (hereinafter, uplink transmission) for indicating resumption of uplink transmission. It can be identified whether it is MAC CE on resume.

Index (Index) LCID value (value) 00000 CCCH 00001-01010 Identity of the logical channel 01011-11000 Reserved 11001 UL Transmission Resume 11010 UL Transmission Stop 11011 Activation / Deactivation 11100 UE Contention Resolution Identity 11101 Timing Advance Command 11110 The DRX command (DRX command) 11111 Padding

Referring to Table 2, if the index of the LCID field is 11010, the corresponding MAC CE is a MAC CE for stopping uplink transmission. If the index of the LCID field is 11001, the corresponding MAC CE is a MAC CE for resuming uplink transmission. For example, the MAC CE for stopping uplink transmission may have a size of 8 bits or more, or may have a zero bit size. Also, for example, the MAC CE for resuming uplink transmission may have a size of 8 bits or more, or may have a zero bit size. Based on the MAC CE for the uplink transmission interruption, the terminal may identify (or determine) a target of the uplink transmission interruption in a serving cell unit, a time alignment group unit, or a terminal unit. In addition, based on the MAC CE for resuming uplink transmission, the UE may identify (or determine) a target of resuming uplink transmission in units of a serving cell, a time alignment group, or a terminal.

Or, as shown in Table 3, the LCID field is a MAC CE (hereinafter, uplink transmission) for indicating that the corresponding MAC CE (620, ..., 625) can enable / disable uplink transmission (or resume / stop uplink transmission). MAC CE for Enable / Disable can be identified.

Index (Index) LCID value (value) 00000 CCCH 00001-01010 Identity of the logical channel 01011-11001 Reserved 11010 UL Transmission Enable / Disable 11011 Activation / Deactivation 11100 UE Contention Resolution Identity 11101 Timing Advance Command 11110 The DRX command (DRX command) 11111 Padding

Referring to Table 3, if the index of the LCID field is 11010, the corresponding MAC CE is a MAC CE for uplink transmission / disablement. Based on the MAC CE for uplink transmission / non-availability, the terminal may determine whether uplink transmission is enabled or disabled in a serving cell unit, a time alignment group unit, or a terminal unit. In this case, the uplink transmission disable may have the same meaning as the uplink transmission interruption described above, and the uplink transmission possible may have the same meaning as resuming the uplink transmission described above.

Interrupting uplink transmission or resuming uplink transmission may be performed through UE specific signaling by an appointment between a base station and a terminal, and may be performed through TAG specific signaling. It may be performed through cell specific signaling. In addition, uplink transmission interruption, uplink transmission resumption, or uplink transmission enable / disable may be performed through hybrid signaling that combines UE specification and cell specification, or combines UE specification and time alignment group specification. Hereinafter, the example will be described in detail.

1. When uplink transmission is suspended or uplink transmission is resumed through UE specific signaling

7 is a block diagram illustrating a structure of a MAC subheader according to an embodiment of the present invention.

Referring to FIG. 7, the subheader 700 includes two R fields 705, an E field 710, and an LCID field 715. The R field 705 is a reserved bit and may be set to zero. E field 710 is a flag indicating whether more fields are present in the MAC header. For example, if the E field 710 is set to 1, it indicates that there is at least one MAC subheader. If the E field 710_ is set to 0, the MAC SDU, MAC CE, or padding is the next byte. Instructs to begin at. The LCID field 715 indicates an LCID index as shown in Table 1 or Table 2 and may correspond to a MAC CE for stopping uplink transmission or an MCE CE for resuming uplink transmission.

For example, the LCID index is defined as shown in Table 1, and the LCID index is 11010. That is, it indicates that the uplink transmission of the terminal is stopped. In this case, the MAC CE for stopping uplink transmission corresponding to the LCID field 715 may have a zero bit size. In this case, it may indicate an uplink transmission stop for all secondary serving cells (SCell) of the terminal. Or in this case, it may indicate that uplink transmission is stopped for the main serving cell (Pcell) and all secondary serving cells of the terminal. The detailed definition of the uplink transmission interruption is as described above.

As another example, the terminal may be set to the uplink transmission possible state for all the serving cells in the terminal by default (default) setting, the terminal initially (or odd number) to receive the MAC CE for the uplink transmission interruption In this case, the MAC CE regarding the uplink transmission stop may indicate the uplink transmission stop. In this case, the MAC CE for stopping uplink transmission corresponding to the LCID field 715 may have a zero bit size. In this case, the MAC CE may indicate an uplink transmission stop for all secondary serving cells (SCell) of the terminal. Or in this case, it may indicate that uplink transmission is stopped for the main serving cell (Pcell) and all secondary serving cells of the terminal. The detailed definition of the uplink transmission interruption is as described above. The terminal sets the current state to the uplink transmission stop state. Subsequently, if the MAC CE regarding the uplink transmission interruption is received again (or an even number), the MAC CE regarding the uplink transmission interruption may indicate resumption of the uplink transmission. In this case, the MAC CE may indicate that uplink transmission is possible for all secondary serving cells (SCells) of the terminal. Or in this case, it may indicate that uplink transmission is possible for the primary serving cell (Pcell) and all secondary serving cells of the terminal. In this case, the terminal sets the current state to an uplink transmission possible state. That is, the MAC CE for stopping the uplink transmission may be used as an indicator to toggle (or disable or enable) the uplink transmission status of the terminal. That is, in this case, the MAC CE for stopping the uplink transmission may operate as an uplink transmission stop indicator or as an uplink transmission resume indicator. This is also the case for the MAC CE for resuming uplink transmission.

As another example, the LCID index is defined as shown in Table 2, and when the LCID index is 11010, it indicates that the uplink transmission of the UE is stopped, and if it is 11001, the UE indicates resuming uplink transmission. At this time, the MAC CE for stopping or resuming uplink transmission corresponding to the LCID field 715 may have a zero bit size. In this case, it may indicate that uplink transmission is stopped or resumed for all secondary serving cells of the terminal. Or in this case, it may indicate that the uplink transmission is stopped or resumed for the main serving cell and all secondary serving cells of the terminal.

2. When uplink transmission is interrupted or uplink transmission is resumed through time alignment group specific signaling

8 is a block diagram illustrating a structure of a MAC subheader according to another embodiment of the present invention.

Referring to FIG. 8, the subheader 800 includes a TAG ID field 805, an E field 810, and an LCID field 815. The LCID field 815 indicates an LCID index as shown in Table 1 or Table 2 and may correspond to a MAC CE for stopping uplink transmission or a MAC CE for resuming uplink transmission. The TAG ID field 805 may have a size of 2 bits and may indicate a target TAG ID. For example, the TAG ID field 805 may indicate any one of TAG1 to TAG4.

For example, the LCID index is defined as shown in Table 1, and the LCID index is 11010. At this time, the LCID field 815 corresponds to the MAC CE for stopping uplink transmission. The MAC CE for stopping the corresponding uplink transmission may have a zero bit size. In this case, the LCID field 815 may indicate the suspension of uplink transmission for all secondary serving cells (SCells) of the TAG indicated by the TAG ID field 805. For example, when the TAG indicated by the TAG ID field 805 is a pTAG, the LCID field 815 may indicate an interruption of uplink transmission for secondary serving cells other than the primary serving cell.

As another example, the LCID index is defined as shown in Table 2, and if the LCID index is 11010, the LCID field 815 corresponds to the MAC CE for stopping uplink transmission, and if the LCID index is 11001, the LCID field 815 transmits an uplink. Corresponds to MAC CE on resume. The MAC CE for stopping or resuming the uplink transmission may have a zero bit size. In this case, the LCID field 815 may indicate stopping or resuming uplink transmission for all secondary serving cells (SCells) of the TAG indicated by the TAG ID field 805. For example, when the TAG indicated by the TAG ID field 805 is a pTAG, the LCID field 815 may indicate resumption of uplink transmission for secondary serving cells other than the primary serving cell.

9 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.

Referring to FIG. 9, the subheader 900 includes two R fields 905, an E field 910, and an LCID field 915. The LCID field 915 may correspond to a MAC CE for interrupting uplink transmission or a MAC CE for resuming uplink transmission.

The MAC CE 950 includes six R fields 955 and a TAG ID field 960. The TAG ID field 960 may have a size of 2 bits and may indicate an ID of a TAG which is to be suspended or resumed from uplink transmission. For example, the TAG ID field 960 may indicate any one of TAG1 to TAG4.

For example, the LCID index is defined as shown in Table 1, and the LCID index is 11010. That is, it indicates that the uplink transmission is stopped. At this time, the LCID field 915 corresponds to the MAC CE for stopping the uplink transmission. The MAC CE for stopping the corresponding uplink transmission includes octet 1 (OCT 1). One octet is 8 bits and contains information on uplink transmission interruption. In this case, the LCID field 915 may indicate an interruption of uplink transmission for all secondary serving cells of a TAG indicated by the TAG ID field 960. For example, when the TAG indicated by the TAG ID field 960 is a pTAG, the LCID field 915 may indicate an interruption of uplink transmission for secondary serving cells except the main serving cell.

As another example, the LCID index is defined as shown in Table 2, and when the LCID index is 11010, the uplink transmission is suspended and the 11001 indicates the uplink transmission resume. At this time, the LCID field 915 corresponds to the MAC CE for stopping or resuming uplink transmission. The MAC CE for suspending or resuming the corresponding uplink transmission includes octet 1. One octet is 8 bits and contains information on stopping or resuming uplink transmission. In this case, the LCID field 915 may indicate stopping or resuming uplink transmission for all secondary serving cells of a TAG indicated by the TAG ID field 960.

10 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.

Referring to FIG. 10, the subheader 1000 includes two R fields 1005, an E field 1010, and an LCID field 1015. The LCID index indicated by the LCID field 1015 is defined as shown in Table 3. In this case, the LCID field 1015 may correspond to the uplink transmission / disable MAC CE 1050. For example, if the LCID index is 11010, it may correspond to the MAC CE 1050 regarding uplink transmission / disablement.

The uplink transmit / disable MAC CE 1050 includes octet 1 (OCT 1). One octet is 8 bits and includes information about uplink transmission (or uplink transmission resumed, equal to hereinafter) and uplink transmission disabled (uplink transmission interrupted, hereinafter) of a TAG. The uplink transmit / disable MAC CE 1050 specifically includes four R fields 1055 and four G _i fields 1060. G _i field 1060 is G ₀ , G ₁ , G ₂ , G ₃ Contains a field. G _i The field 1060 indicates an uplink transmission / disable state of a TAG having an ID of i. The uplink transmission possible state may mean an uplink transmission resume state, and the uplink transmission disabled state may mean an uplink transmission interrupted state.

For example, G ₀ field indicating uplink transmission enable / disable state of the TAG0, and G ₁ field uplink transmission available / indicate a disabled state, and G ₂ field of TAG1 can be sent uplink of TAG2 / Disable Status, and the G ₃ field may indicate the uplink transmission / disable state of TAG3. For example, when the G _i field is set to 0, it indicates that uplink transmission of the corresponding target TAG is possible, and when the G _i field 1060 is set to 1, it indicates that uplink transmission of the corresponding target TAG is not available. Can be. Specifically, for example, when the G ₀ field is set to 0, the G ₁ field is set to 0, the G ₂ field is set to 1, and the G ₃ field is set to 1, uplink transmission of pTAG is possible, sTAG1 It may mean that uplink transmission of sTAG2 is impossible, uplink transmission of sTAG2 is impossible, and uplink transmission of sTAG3 is impossible. In addition, for example, when the G ₀ field corresponding to the pTAG is set to 1, which means that uplink transmission of the pTAG is impossible, it may mean that only uplink transmission of secondary serving cells in the pTAG is impossible. G _i The field 1060 may be set to a value (for example, 0) indicating that uplink transmission is possible by default.

3. When uplink transmission is suspended or uplink transmission is resumed through cell specific signaling

11 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.

Referring to FIG. 11, the subheader 1100 includes two R fields 1105, an E field 1110, and an LCID field 1115. The LCID index indicated by the LCID field 1015 is shown in Table 3. In this case, the LCID field 1115 may correspond to the uplink transmission / deactivation MAC CE 1150. For example, if the LCID index is 11010, it may correspond to the MAC CE 1150 regarding uplink transmission / non-availability.

The uplink transmit / disable MAC CE 1150 includes octet 1 (OCT 1). One octet is 8 bits and includes information about uplink transmission and uplink transmission disable of the serving cell. The uplink transmit / disable MAC CE 1150 includes seven C _i fields 1155 and an R field 1160. Although the position of the R field 1160 is indicated as being located at the far right of the octet, this is merely an example, and the technical idea of the present invention includes an embodiment in which the R field 1160 is positioned at the far left of the octet.

The C _i field 1155 includes C ₇ , C ₆ , C ₅ , C ₄ , C ₃ , C ₂ , C ₁ fields. C _i The field 1155 indicates an uplink transmission / disable state for the secondary serving cell of the index i. For example, the C ₁ field indicates an uplink transmission / disable state of the secondary serving cell 1, the C ₂ field indicates an uplink transmission / disable state of the secondary serving cell 2, and the C ₃ field indicates a secondary serving Cell 3 indicates an uplink transmission / disable state, a C ₄ field indicates an uplink transmission / disable state of a secondary serving cell 4, and a C ₅ field indicates an uplink transmission / disable state of a secondary serving cell 5 In this case, the C ₆ field may indicate an uplink transmission / disable state of the secondary serving cell 6, and the C ₇ field may indicate an uplink transmission / disable state of the secondary serving cell 7. For example, when the C _i field 1155 is set to 0, it indicates that uplink transmission of the secondary serving cell i is possible, and when the C _i field is set to 1, it indicates that the uplink transmission of the secondary serving cell i is disabled. Can be. Specifically, for example, when the C ₁ , C ₃ , C ₅ fields are set to 0, and the C ₂ , C ₄ , C ₆ , C ₇ fields are set to 1, secondary serving cell 1, secondary serving cell 3, secondary serving The uplink transmission of the cell 5, the secondary serving cell 2, the secondary serving cell 4, the secondary serving cell 6, it may mean that the uplink transmission of the secondary serving cell 7. The C _i field 1155 may be set to, for example, a value indicating that uplink transmission is possible by default.

4. When uplink transmission is interrupted or uplink transmission is resumed through hybrid signaling

12 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.

Referring to FIG. 12, the subheader 1200 includes an R field 1205, an F field 1210, an E field 1215, and an LCID field 1220. The LCID field 1220 may correspond to a MAC CE for stopping uplink transmission or a MAC CE for resuming uplink transmission. The F field 1210 indicates the type of the corresponding MAC CE. For example, if the F field 1210 is set to 0, the MAC CE indicated by the LCID field 1220 may be a MAC bit 1230 of zero bit size, and the F field 1210 is set to one. If set, the MAC CE 1250 indicated (or corresponding) by the LCID field 1220 may include octet 1.

For example, the LCID index indicated by the LCID field 1220 is defined as shown in Table 1. If the LCID index is 11010, the LCID field 1220 corresponds to the MAC CE for stopping uplink transmission. In this case, if the F field 1210 is set to 0, the MAC CE for the corresponding uplink transmission interruption is the MAC CE 1230 of zero bit size and indicates the uplink transmission interruption for all secondary serving cells of the terminal. Can be. Also, if the F field 1210 is set to 1, the MAC CE for the corresponding uplink transmission interruption is the MAC CE 1250 including octet 1. In this case, the MAC CE 1250 may include six R fields 1255 and one TAG ID field 1260. The TAG ID field 1260 may indicate a TAG that is a target of uplink transmission suspension. In this case, this may mean stopping uplink transmission for all secondary serving cells of a target TAG.

As another example, the LCID index indicated by the LCID field 1220 is defined as shown in Table 2. If the LCID index is 11001, the LCID field 1220 corresponds to the MAC CE for resuming uplink transmission. In addition, if the LCID index is 11010, the LCID field 1220 corresponds to the MAC CE for stopping the uplink transmission. In this case, if the F field 1210 is set to 0, the MAC CE for stopping or resuming the corresponding uplink transmission is the MAC CE 1230 having a zero bit size and stopping uplink transmission for all secondary serving cells of the terminal. Or resume. Also, if the F field 1210 is set to 1, the MAC CE for stopping or resuming the corresponding uplink transmission is the MAC CE 1250 including octet 1. FIG. In this case, the MAC CE 1250 may include six R fields 1255 and one TAG ID field 1260. The TAG ID field 1260 may indicate a TAG which is to be suspended or resumed from uplink transmission. In this case, this may mean stopping or resuming uplink transmission for all secondary serving cells of a target TAG.

13 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.

Referring to FIG. 13, the subheader 1300 includes an R field 1305, an F field 1310, an E field 1315, and an LCID field 1320. The LCID field 1320 may correspond to a MAC CE for stopping uplink transmission or a MAC CE for resuming uplink transmission. The F field 1310 indicates the type of the corresponding MAC CE. For example, if the F field 1310 is set to 0, the MAC CE indicated by the LCID field 1320 may be a MAC bit 1330 of zero bit size, and the F field 1310 is set to 1. If set, the MAC CE 1350 indicated (or corresponding) by the LCID field 1320 may include octet 1.

For example, the LCID index indicated by the LCID field 1320 is defined as shown in Table 1. If the LCID index is 11010, it corresponds to the MAC CE for stopping uplink transmission. In this case, if the F field 1310 is set to 0, the MAC CE for the corresponding uplink transmission interruption is the MAC CE 1330 of zero bit size and indicates the uplink transmission interruption for all secondary serving cells of the terminal. Can be. In addition, if the F field 1310 is set to 1, the MAC CE for the corresponding uplink transmission interruption is the MAC CE 1250 including octet 1. In this case, the MAC CE 1350 may specifically include four R fields 1355 and four G _i fields 1360. G _i field 1360 is G ₀ , G ₁ , G ₂ , G ₃ Contains a field. G _i The field 1360 may indicate an uplink transmission / disable state of a TAG having an ID of i. As described above, the uplink transmission possible state may mean an uplink transmission resume state, and the uplink transmission stop state may mean an uplink transmission stop state. For example, G ₀ field indicating uplink transmission enable / disable state of the TAG0, and G ₁ field uplink transmission available / indicate a disabled state, and G ₂ field of TAG1 can be sent uplink of TAG2 / Disable Status, and the G ₃ field may indicate the uplink transmission / disable state of TAG3. For example, when the G _i field is set to 0, this indicates uplink transmission of the corresponding target TAG, and when the G _i field 1360 is set to 1, it indicates that the uplink transmission of the corresponding target TAG is disabled. Can be.

As another example, the LCID index indicated by the LCID field 1320 may be defined as shown in Table 2. If the LCID index is 11001, the LCID field 1320 corresponds to the MAC CE for resuming uplink transmission. If the LCID index is 11010, the LCID field 1320 corresponds to the MAC CE for stopping uplink transmission. In this case, if the F field 1310 is set to 0, the MAC CE for stopping or resuming the corresponding uplink transmission is the MAC CE 1330 having a zero bit size, and stopping uplink transmission for all secondary serving cells of the terminal. Or resume. Also, if the F field 1310 is set to 1, the MAC CE for resuming corresponding uplink transmission is the MAC CE 1350 including octet 1. In this case, the MAC CE 1350 may specifically include four R fields 1355 and four G _i fields 1360. G _i field 1360 is G ₀ , G ₁ , G ₂ , G ₃ Contains a field. G _i The field 1360 may indicate an uplink transmission / disable state of TAG i. For example, G ₀ field indicating uplink transmission enable / disable state of the TAG0, and G ₁ field uplink transmission available / indicate a disabled state, and G ₂ field of TAG1 can be sent uplink of TAG2 / Disable Status, and the G ₃ field may indicate the uplink transmission / disable state of TAG3. For example, when the G _i field is set to 0, it indicates that uplink transmission of the corresponding target TAG is possible, and when the G _i field 1360 is set to 1, it may indicate that uplink transmission of the TAG i is not possible. .

14 is a block diagram illustrating a structure of a MAC subheader and a corresponding MAC CE according to another embodiment of the present invention.

Referring to FIG. 14, the subheader 1400 includes an R field 1405, an F field 1410, an E field 1415, and an LCID field 1420. The LCID field 1420 may correspond to a MAC CE for interrupting uplink transmission or a MAC CE for resuming uplink transmission. The F field 1410 indicates the type of the corresponding MAC CE. For example, if the F field 1410 is set to zero, the MAC CE indicated by the LCID field 1420 may be a MAC CE 1430 of zero bit size, and the F field 1410 is set to one. If set, the MAC CE 1450 indicated (or corresponding) by the LCID field 1420 may include octet 1.

For example, as shown in Table 1, if the LCID index is 11010, it corresponds to the MAC CE for stopping uplink transmission. In this case, if the F field 1410 is set to 0, the MAC CE for the corresponding uplink transmission interruption is the MAC CE 1430 of zero bit size and indicates the uplink transmission interruption for all secondary serving cells of the terminal. Can be. Also, if the F field 1410 is set to 1, the MAC CE for stopping corresponding uplink transmission is the MAC CE 1450 including octet 1. FIG. In this case, the MAC CE 1450 may specifically include a C _i field 1455 and an R field 1460 of 7. The C _i field 1455 includes C ₇ , C ₆ , C ₅ , C ₄ , C ₃ , C ₂ , C ₁ fields. C _i The field 1455 may indicate an uplink transmission / disable state of each corresponding secondary serving cell. For example, the C ₁ field indicates an uplink transmission / disable state of the secondary serving cell 1, the C ₂ field indicates an uplink transmission / disable state of the secondary serving cell 2, and the C ₃ field indicates a secondary serving Cell 3 indicates an uplink transmission / disable state, a C ₄ field indicates an uplink transmission / disable state of a secondary serving cell 4, and a C ₅ field indicates an uplink transmission / disable state of a secondary serving cell 5 In this case, the C ₆ field may indicate an uplink transmission / disable state of the secondary serving cell 6, and the C ₇ field may indicate an uplink transmission / disable state of the secondary serving cell 7. For example, when the C _i field 1455 is set to 0, this indicates that uplink transmission of the corresponding target secondary serving cell is possible. When the C _i field is set to 1, the uplink of the corresponding target secondary serving cell is set. It may indicate a transmission failure.

As described above, according to the structure of the subheader according to the present invention and the structure of the MAC CE, the base station may transmit an indicator to the terminal for indicating uplink transmission stop and uplink transmission resume (or uplink transmission / non-availability). The uplink transmission stop indicator and the uplink transmission resume indicator may indicate an uplink transmission stop, resume or enable / disable target in a UE-specific, time-aligned group-specific, serving cell-specific, or a combination thereof. Through this, the base station can adaptively control uplink transmission through the component carrier in the component carrier system performing communication using a plurality of component carriers. Through this, the base station can block unnecessary uplink transmission of the terminal and at the same time reduce the battery consumption of the terminal.

15 is a flowchart illustrating a method of interrupting and resuming uplink transmission of a terminal according to an embodiment of the present invention.

Referring to FIG. 15, the terminal performs an RRC connection establishment procedure with the base station (S1500). The RRC connection setup procedure includes a terminal transmitting an RRC connection request message to a base station, a base station transmitting an RRC connection setup message to a terminal, and a terminal transmitting an RRC connection setup complete message to a base station. The purpose of the RRC connection establishment procedure is to establish an RRC connection. The RRC connection setup includes the setup of signaling radio bearer1.

The terminal performs a secondary serving cell configuration procedure for additionally configuring at least one secondary serving cell in the terminal (S1510). The secondary cell configuration procedure includes transmitting an RRC connection reconfiguration message and transmitting a RRC connection reconfiguration complete message to the base station by the terminal. The RRC connection reconfiguration message may include a secondary serving cell configuration information field including information on the configuration of the secondary serving cell added to the terminal.

The terminal receives an activation indicator for activating some or all of the secondary serving cells configured in the terminal from the base station (S1520). The activation indicator may be received in a MAC message. The MAC message may be called a MAC PDU. The MAC message includes at least one MAC CE. The terminal may activate some or all of the secondary serving cells configured in the terminal based on the secondary serving cell activation indicator.

In addition, the terminal may perform a timing reference serving cell configuration and a random access procedure. The UE may acquire a valid time alignment value based on a timing reference serving cell in each time alignment group through a random access procedure.

The terminal receives an uplink transmission stop indicator from the base station instructing to stop uplink transmission of some or all of the serving cells configured in the terminal (S1530). The uplink transmission stop indicator may be received in a MAC message. Or MAC message includes at least one MAC CE, the MAC CE includes an uplink transmission stop indicator. In this case, the MAC CE including the uplink transmission stop indicator may include the MAC CE for the uplink interrupt or the MAC CE for uplink transmission / disable. The uplink transmission stop indicator may indicate an uplink transmission stop (or disable) target in a terminal specific, a time alignment group specific, a serving cell specific, or a combination thereof. The MAC CE and the MAC subheader corresponding to the MAC CE include the structure of any one of FIGS. 7 to 14. As described above, the MAC CE may have a zero bit size in some cases.

Although FIG. 15 illustrates that S1530 is performed after S1520, S1530 may be performed simultaneously with S1520. That is, the uplink transmission stop indicator may be received in the MAC message including the activation indicator in S1520.

The terminal stops uplink transmission of some or all of the serving cells (including the primary serving cell and the secondary serving cells) based on the uplink transmission stop indicator (S1540). In this case, the terminal may stop the uplink transmission in the serving cell unit, the TAG unit, or the terminal unit based on the uplink transmission stop indicator.

The terminal receives from the base station an uplink transmission resume indicator indicating that the uplink transmission of some or all of the serving cells configured in the terminal is resumed (S1550). The uplink transmission resume indicator may be received in a MAC message. The MAC message includes at least one MAC CE, and the MAC CE includes an uplink transmission resume indicator. In this case, the MAC CE including the uplink transmission resumption indicator may include the above-described MAC CE for resuming uplink or MAC CE for uplink transmission / disable. In addition, when the MAC CE regarding the uplink transmission interruption is used as an indicator for toggling the uplink transmission state of the UE to the interruption or resumption as described above, the MAC CE regarding the uplink transmission interruption includes an uplink transmission resume indicator. The uplink transmission resumption indicator may indicate a user equipment specific, a time alignment group specific, a serving cell specific, or a combination thereof in order to resume uplink transmission (or possible). The MAC CE and the MAC subheader corresponding to the MAC CE include the structure of any one of FIGS. 7 to 14. As described above, the MAC CE may have a zero bit size in some cases.

Although FIG. 15 illustrates that S1550 is performed after S1530, S1550 may be performed simultaneously with S1530. That is, the uplink transmission resume indicator may be included in the MAC message together with the uplink transmission stop indicator in S1530.

The terminal resumes uplink transmission of some or all of the serving cells (including the primary serving cell and the secondary serving cells) based on the uplink transmission resume indicator (S1560). In this case, the terminal may resume uplink transmission on a serving cell basis, TAG basis, or terminal basis based on the uplink transmission stop indicator.

16 is a flowchart illustrating a method of interrupting and resuming uplink transmission of a base station according to an embodiment of the present invention.

Referring to FIG. 16, the base station performs an RRC connection establishment procedure with the terminal (S1600). The RRC connection setup procedure includes a terminal transmitting an RRC connection request message to a base station, a base station transmitting an RRC connection setup message to a terminal, and a terminal transmitting an RRC connection setup complete message to a base station. The purpose of the RRC connection establishment procedure is to establish an RRC connection. The RRC connection setup includes the setup of signaling radio bearer1.

The base station performs a secondary serving cell configuration procedure for additionally configuring at least one secondary serving cell in the terminal (S1610). The secondary cell configuration procedure includes transmitting an RRC connection reconfiguration message and transmitting a RRC connection reconfiguration complete message to the base station by the terminal. The RRC connection reconfiguration message may include a secondary serving cell configuration information field including the content of the secondary serving cell added to the terminal.

The base station transmits an activation indicator for activating some or all of the secondary serving cells configured in the terminal to the terminal (S1620). The activation indicator may be transmitted in a MAC message. The MAC message may be called a MAC PDU. The MAC message includes at least one MAC CE. As the base station activates some or all of the secondary serving cells, the base station may allocate resources for secondary serving cells configured in the terminal.

If necessary, the base station may inform the terminal of each time alignment value for at least one time alignment group configured in the terminal by performing a random access procedure with the terminal.

The base station identifies (or determines) a serving cell (or time alignment group) that is a target of uplink transmission interruption among serving cells (or time alignment group) configured in the terminal, and serves cells (or time alignment) configured in the terminal. In step S1630, an uplink transmission resume indicator indicating that the uplink transmission of some or all of the groups is resumed. The uplink transmission resume indicator may be transmitted in a MAC message. The MAC message includes at least one MAC CE, and the MAC CE includes an uplink transmission resume indicator. In this case, the MAC CE including the uplink transmission resumption indicator may include the above-described MAC CE for resuming uplink or MAC CE for uplink transmission / disable. The uplink transmission resumption indicator may indicate a user equipment specific, a time alignment group specific, a serving cell specific, or a combination thereof in order to resume uplink transmission (or possible). The MAC CE and the MAC subheader corresponding to the MAC CE include the structure of any one of FIGS. 7 to 14. As described above, the MAC CE may have a zero bit size in some cases.

Although FIG. 16 illustrates that S1630 is performed after S1620, S1630 may be performed simultaneously with S1620. That is, the uplink transmission stop indicator may be included in the MAC message including the activation indicator in S1620 and transmitted to the terminal.

The base station identifies (or determines) a serving cell (or time alignment group) that is a target of resuming uplink transmission among serving cells (or time alignment groups) configured in the terminal, and serves cells (or time alignment) configured in the terminal. The uplink transmission resume indicator indicating that the uplink transmission of some or all of the groups) is transmitted to the terminal (S1640). The uplink transmission resume indicator may be transmitted in a MAC message. The MAC message includes at least one MAC CE, and the MAC CE includes an uplink transmission resume indicator. In this case, the MAC CE including the uplink transmission resumption indicator may include the MAC CE for resuming uplink or the MAC CE for uplink transmission / disable. In addition, when the MAC CE regarding the uplink transmission interruption is used as an indicator for toggling the uplink transmission state of the UE to the interruption or resumption as described above, the MAC CE regarding the uplink transmission interruption includes an uplink transmission resume indicator. The uplink transmission resumption indicator may indicate a user equipment specific, a time alignment group specific, a serving cell specific, or a combination thereof in order to resume uplink transmission (or possible). The MAC CE and the MAC subheader corresponding to the MAC CE include the structure of any one of FIGS. 7 to 14. As described above, the MAC CE may have a zero bit size in some cases.

Although FIG. 16 illustrates that S1640 is performed after S1630, S1640 may be performed simultaneously with S1630. That is, the uplink transmission resume indicator may be included in the MAC message together with the uplink transmission stop indicator in S1630 and transmitted to the terminal.

FIG. 17 is a block diagram illustrating a terminal and a base station performing interruption and resumption of uplink transmission according to an example of the present invention.

Referring to FIG. 17, the terminal 1700 includes a terminal RF unit 1705 and a terminal processor 1710. The terminal processor 1710 includes a MAC message processor 1711 and an uplink transmission controller 1712.

The terminal RF unit 1705 receives at least one of an uplink transmission stop indicator and an uplink transmission resume indicator from the base station 1750. The uplink transmission stop indicator and the uplink transmission resume indicator may be received in a MAC message. The MAC message may include at least one MAC CE, and the MAC CE may include at least one of an uplink transmission stop indicator and an uplink transmission resume indicator. For example, the MAC CE may include the above-described MAC CE for uplink interruption, MAC CE for resuming uplink transmission, or MAC CE for uplink transmission / disable. The uplink transmission stop indicator and the uplink transmission resume indicator may be terminal-specific, time-aligned group-specific, serving cell-specifically, or a combination thereof, and / or resume uplink transmission (or disable) target or uplink transmission (or Can be indicated. The MAC CE and the MAC subheader corresponding to the MAC CE include the structure of any one of FIGS. 7 to 14. As described above, the MAC CE may have a zero bit size in some cases. In addition, the MAC CE for stopping (or resuming) uplink transmission indicates that the uplink transmission is interrupted when transmitted once (odd times) and instructed to resume uplink transmission when transmitted again (even times). You may. In this case, the MAC CE may operate as an indicator to toggle uplink transmission to stop or resume. In this case, the MAC CE for stopping (or resuming) the uplink transmission may mean an uplink transmission stop indicator indicating an uplink transmission stop, or an uplink transmission resume indicator indicating restart of uplink transmission. It may mean.

In addition, the terminal RF unit 1705 may receive an activation indicator from the base station 1750 through a MAC message as necessary.

The MAC message processing unit 1711 interprets the received MAC message by the terminal RF unit 1705 and transmits an uplink transmission instructing to stop uplink transmission of some or all of the serving cells configured in the terminal 1700. Obtain an abort indicator. In addition, the MAC message processing unit 1711 interprets the MAC message received by the terminal RF unit 1705 and indicates an uplink indicating resuming uplink transmission of some or all of the serving cells configured in the terminal 1700. Obtain the resume transmission indicator. Specifically, the MAC message processing unit 1711 analyzes the LCID of the MAC subheader included in the received MAC message to determine whether the MAC CE corresponding to the MAC subheader is the MAC CE for stopping the uplink transmission. Whether the MAC CE is related to the MAC CE for uplink transmission / disablement and whether the uplink transmission is stopped or resumed by interpreting the TAG ID field, the Gi field, or the Ci field of the MAC subheader or the corresponding MAC CE. It can be confirmed and the target can be confirmed by the terminal unit, time alignment group unit, or serving cell unit.

The uplink transmission control unit 1712 stops uplink transmission of some or all of the serving cells (including the main serving cell and the secondary serving cells) based on the uplink transmission stop indicator. In this case, the terminal 1700 may perform an uplink transmission interruption in a serving cell unit, a TAG unit, or a terminal unit based on the uplink transmission stop indicator. In addition, the uplink transmission control unit 1712 resumes uplink transmission of some or all of the serving cells (including the main serving cell and the secondary serving cells) based on the uplink transmission resume indicator. In this case, the terminal 1700 may resume uplink transmission in a serving cell unit, a TAG unit, or a terminal unit based on the uplink transmission stop indicator.

The base station 1750 includes a base station RF unit 1755 and a base station processor 1760. The base station processor 1760 includes a MAC message processor 1762 and an uplink transmission determiner 1762.

The uplink transmission determination unit 1762 identifies (or determines) a serving cell that is a target of downlink transmission from among the serving cells configured in the terminal. Alternatively, the uplink transmission determination unit 1762 checks (or determines) a time alignment group that is the target of downlink transmission among the time alignment groups configured in the terminal.

In addition, the uplink transmission determiner 1762 identifies (or determines) a serving cell that is a target of resuming uplink transmission among the serving cells configured in the terminal. Alternatively, the uplink transmission determination unit 1762 checks (or determines) a time alignment group that is a target of resuming uplink transmission among time alignment groups configured in the terminal.

The MAC message processor 1701 is an uplink transmission stop indicator for instructing to stop uplink transmission of some or all of the serving cells or time alignment groups configured in the terminal 1700 and uplink transmission for instructing to resume uplink transmission. At least one of the indicators is generated and sent to the base station RF unit 1755. In this case, the uplink transmission stop indicator and the uplink transmission resume indicator may be generated as a MAC message. In this case, the MAC message may include at least one MAC CE, and the MAC CE may include at least one of an uplink transmission stop indicator and an uplink transmission resume indicator. For example, the MAC CE may include the above-described MAC CE for uplink interruption, MAC CE for resuming uplink transmission, or MAC CE for uplink transmission / disable. Here, the MAC CE regarding uplink interruption (or resumption) may be an indicator that triggers a state of the UE to stop or resume uplink transmission as described above. In this case, the MAC CE for stopping (or resuming) the uplink transmission may in some cases mean an uplink transmission stop indicator or an uplink transmission resume indicator.

The uplink transmission stop indicator and the uplink transmission resume indicator may be terminal-specific, time-aligned group-specific, serving cell-specifically, or a combination thereof, and / or resume uplink transmission (or disable) target or uplink transmission (or Can be indicated. The MAC CE and the MAC subheader corresponding to the MAC CE include the structure of any one of FIGS. 7 to 14. As described above, the MAC CE may have a zero bit size in some cases.

The base station RF unit 1755 transmits the MAC message including at least one of the uplink transmission stop indicator and the uplink transmission resume indicator to the terminal 1700.

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 (20)

A method for controlling uplink transmission by a terminal in a multi-component carrier system,
Receiving a medium access control (MAC) message from a base station including an uplink transmission stop indicator indicating an uplink transmission stop of a serving cell configured in the terminal; And
And setting a state of the serving cell configured in the terminal to an uplink transmission stop state according to the indication of the uplink transmission stop indicator. The method according to claim 1,
The uplink transmission stop indicator is composed of a MAC subheader and a MAC control element (CE) corresponding to the MAC subheader,
And the MAC subheader includes a Logical Channel ID (LCID) field indicating that the MAC CE is about stopping the uplink transmission. 3. The method of claim 2,
The MAC CE is a MAC CE having a size of zero bits. 3. The method of claim 2,
The MAC CE includes a Gi field indicating whether to stop uplink transmission for a timing alignment group (TAG) including the serving cell. 3. The method of claim 2,
The MAC CE includes a Ci field indicating whether to stop uplink transmission for the serving cell. A method for controlling uplink transmission by a base station in a multi-component carrier system,
Determining an uplink transmission stop of a serving cell configured in a terminal;
Generating a MAC message including an uplink transmission stop indicator indicating an uplink transmission stop of a serving cell configured in the terminal; And
And transmitting the MAC message to a terminal. The method according to claim 6,
The uplink transmission stop indicator is composed of a MAC subheader and a MAC control element corresponding to the MAC subheader,
And the MAC subheader includes a logical channel identification field indicating that the MAC CE is related to the uplink transmission interruption. 8. The method of claim 7,
The MAC CE is a MAC CE having a zero bit size, uplink transmission control method. 8. The method of claim 7,
The MAC CE includes a Gi field indicating whether to stop uplink transmission for a time alignment group including the serving cell. 8. The method of claim 7,
The MAC CE, characterized in that it comprises a Ci field indicating whether the uplink for the secondary serving cell, uplink transmission control method. A terminal for controlling uplink transmission in a multi-component carrier system,
A terminal RF unit for receiving a MAC message including an uplink transmission stop indicator indicating an uplink transmission stop of a serving cell configured in the terminal from a base station;
A MAC message processing unit for obtaining the uplink transmission stop indicator based on the MAC message; And
And an uplink transmission control unit configured to set a state of the serving cell configured in the terminal to an uplink transmission stop state based on the uplink transmission stop indicator. 12. The method of claim 11,
The uplink transmission stop indicator is composed of a MAC subheader and a MAC CE corresponding to the MAC subheader,
And wherein the MAC subheader includes a logical channel identification field indicating that the MAC CE is related to stopping uplink transmission. 13. The method of claim 12,
The MAC CE is characterized in that the MAC CE having a zero bit size. 13. The method of claim 12,
The MAC CE is characterized in that it comprises a Gi field indicating whether or not to stop the uplink transmission for the time alignment group including the serving cell. 13. The method of claim 12,
The MAC CE, characterized in that it comprises a Ci field indicating whether or not to stop the uplink transmission for the serving cell. A base station for performing uplink transmission control in a multi-component carrier system.
An uplink transmission determining unit determining whether uplink transmission of the serving cell configured in the terminal is stopped;
A MAC message processor for generating a MAC message including an uplink transmission stop indicator indicating an uplink transmission stop of a serving cell configured in the terminal; And
And a base station RF unit for transmitting the MAC message to the terminal. 17. The method of claim 16,
The uplink transmission stop indicator is composed of a MAC subheader and a MAC CE corresponding to the MAC subheader,
And wherein the MAC subheader includes a logical channel identification field indicating that the MAC CE is about stopping the uplink transmission. 18. The method of claim 17,
And the MAC CE is a MAC CE having a zero bit size. 18. The method of claim 17,
The MAC CE includes a Gi field indicating whether to stop uplink transmission for a time alignment group including the serving cell. 18. The method of claim 17,
The MAC CE is characterized in that it comprises a Ci field indicating whether or not to transmit the uplink to the secondary serving cell.

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