KR102244326B1 - Method and apparatus for grouping serving cells - Google Patents

Abstract

The present specification relates to a method and apparatus for grouping serving cells in a multi-component carrier system. In this specification, in a method of grouping serving cells of a base station in a multi-component carrier system, grouping a plurality of component carriers configured in a terminal, and transmitting RRC signaling to the terminal Including the step of, Each group to be grouped provides a method for grouping a serving cell, characterized in that it includes a maximum of 8 component carriers.

Description

Method and apparatus for grouping serving cells in a multi-element carrier system {METHOD AND APPARATUS FOR GROUPING SERVING CELLS}

The present invention relates to wireless communication, and more particularly, to a method and apparatus for grouping serving cells in a multi-element carrier system.

In a general wireless communication system, only one carrier is mainly considered even though the bandwidths between the uplink and the downlink are set differently. In 3rd Generation Partnership Project (3GPP) long term evolution (LTE), based on a single carrier, the number of carriers constituting uplink and downlink is one, and the uplink and downlink bandwidths are generally symmetrical to each other. to be. In such a single carrier system, wireless communication was performed using one carrier.

However, with the recent introduction of a multiple component carrier system, a wireless communication system requires service support through multiple component carriers.

An object of the present invention is to provide a wireless communication method and apparatus capable of reducing overhead to a primary serving cell (Pcell) in a multi-carrier system.

Another technical problem of the present invention is to provide a wireless communication method and apparatus supporting a plurality of component carriers while minimizing changes to the existing physical layer structure.

According to an aspect of the present invention, a method of grouping serving cells of a base station in a multi-component carrier system is provided. The method of grouping the serving cells includes grouping a plurality of component carriers configured in a terminal, and transmitting RRC signaling to the terminal, wherein each grouped group is at most It is implemented including 8 component carriers.

According to another aspect of the present invention, a method of receiving a signal in a serving cell grouped by a terminal in a multi-component carrier system is provided. The signal reception method includes receiving RRC signaling from a base station, wherein each group to be grouped includes a maximum of 8 component carriers.

According to the present invention, by grouping serving cells in a multi-carrier system, an advantage of reducing overhead to a primary serving cell (Pcell) is provided. In addition, it provides an advantage of supporting a plurality of component carriers through the same physical layer structure.

1 shows an example of an LAA network environment to which the present invention is applied.
2 shows an example in which serving cells are grouped for signaling according to an embodiment of the present invention.
3 shows an example of an activation/deactivation MAC CE structure according to an embodiment of the present invention.
4 shows an example of an activation/deactivation MAC CE structure according to another embodiment of the present invention.
5 and 6 show an example of an activation/deactivation MAC CE structure in which four serving cell groups are grouped according to an embodiment of the present invention.
7 shows an example of a MAC CE structure according to another embodiment of the present invention.
8 shows a PHR MAC CE structure according to an embodiment of the present invention.
9 shows an example of a PHR MAC CE structure according to another embodiment of the present invention.
10 is a flowchart illustrating a method of transmitting an RRC signal by a base station according to an embodiment of the present invention.
11 is a flowchart illustrating a method of transmitting a CIF signal by a base station according to an embodiment of the present invention.
12 is a flowchart illustrating MAC CE transmission and reception between a base station and a terminal according to an embodiment of the present invention.
13 is a block diagram showing a wireless communication system in which an embodiment of the present invention is implemented.

Hereinafter, some embodiments will be described in detail through exemplary drawings in the present specification. In adding reference numerals to constituent elements in each drawing, it should be noted that the same constituent elements are given the same reference numerals as much as possible even if they are indicated on different drawings. In addition, in describing an embodiment of the present specification, if it is determined that a detailed description of a related known configuration or function may obscure the subject matter of the present specification, a detailed description thereof will be omitted.

This specification describes a communication network, and operations performed in the communication network are performed in the process of controlling the network and transmitting data in a system (for example, a base station) that governs the communication network, or a terminal linked to the corresponding network. Work can be done in

Terminal (User Equipment: UE) may be fixed or mobile, and may be referred to in other terms such as Mobile Station (MS), Advanced MS (AMS), User Terminal (UT), Subscriber Station (SS), and Wireless Device. Can be called.

A base station generally refers to a station to communicate with a terminal, eNodeB (evolved-NodeB), BTS (Base Transceiver System), access point (Access Point), femto base station (FemtoeNodeB), home base station (Home eNodeB: HeNodeB) , Relay, and remote radio head (RRH). A cell should be interpreted in a comprehensive meaning indicating a partial area covered by a base station, and is meant to encompass all of the various coverage areas such as megacells, macrocells, microcells, picocells, and femtocells.

Carrier aggregation (CA) supports a plurality of carriers, and is also referred to as spectrum aggregation or bandwidth aggregation. Individual unit carriers bound by carrier aggregation are referred to as component carriers (CC). Each component carrier is defined by a bandwidth and a center frequency. For example, if five component carriers are allocated as granularity of a carrier unit having a bandwidth of 20 MHz, a maximum bandwidth of 100 MHz can be supported.

Hereinafter, a multiple carrier system includes a system supporting carrier aggregation (CA). The serving cell may be defined as a component frequency band that can be aggregated by CA based on a multiple component carrier system. Serving cells include a primary serving cell (PCell) and a secondary serving cell (SCell). The primary serving cell is one that provides security input and non-access stratum (NAS) mobility information in the radio resource control (RRC) connection (establishment) or re-establishment state. It means a serving cell. Depending on the capabilities of the terminal, at least one cell may be configured to form a set of serving cells together with a primary serving cell, and the at least one cell is referred to as a secondary serving cell. The set of serving cells configured for one terminal may consist of only one primary serving cell, or may consist of one primary serving cell and at least one secondary serving cell.

When the terminal configures the CA, the terminal has one RRC connection with the network. When RRC connection is established (establishment), re-establishment (re-establishment), or handover is performed, a specific serving cell provides non-access stratum (NAS) mobility information (eg, TAI: Tracking Area ID). Hereinafter, the specific serving cell is referred to as a primary serving cell (PCell). The primary serving cell may be configured of a downlink primary component carrier (DL PCC) and an uplink primary component carrier (UL PCC) in pairs.

Meanwhile, secondary cells (SCells) may be configured in the form of a serving cell set together with a primary serving cell according to the UE's hardware capability. The secondary serving cell may be composed of only a DL SCC (Downlink Secondary Component Carrier), or may be configured in a pair with a UL SCC (Uplink Secondary Component Carrier).

The serving cell set consists of one primary serving cell and at least one secondary serving cell. The primary serving cell can be changed only through a handover procedure, and is used for PUCCH transmission. The primary serving cell cannot transition to an inactive state, but the secondary serving cell can transition to an inactive state.

Meanwhile, for carrier aggregation (CA) supporting multiple component carriers, a system supporting five or more component carriers (CC) may be considered in a system supporting a broadband. . In order to support these technologies, many detailed underlying technologies must be considered.

1 shows an example in which a plurality of UEs perform carrier aggregation on a plurality of component carriers (CCs) in a License Assisted Access (LAA) situation to which the present invention is applied.

In the present invention, LAA refers to a wireless communication technique that supports CA operation for one or more SCells operating in an unlicensed band or an unlicensed spectrum based on the assistance of a PCell operating in a licensed band or spectrum. In other words, LAA is a technology in which the LTE licensed band is an anchor, and the licensed band and the unlicensed band are combined into one using CA. In this case, the licensed band may be used as the primary serving cell and the secondary serving cell, and the unlicensed band may be used only as the secondary serving cell. In addition, the unlicensed band is activated only through CA and may not perform LTE communication alone. The terminal accesses the network through a licensed band to use the service, and the base station can offload the traffic of the licensed band to the unlicensed band by combining the licensed band and the unlicensed band with CA according to the situation.

Referring to FIG. 1, the UE1 may perform CA on five or more licensed carriers (LC) and unlicensed carriers, and the UE2 and the third The UE3 may perform CA in 5 licensed bands and unlicensed band carriers. For example, the first terminal may support up to 32 CCs and may be configured to support 16 CCs. The first to third terminals perform CA by setting the licensed band carrier as Pcell or Scell, and then setting the remaining unlicensed band carriers as Scell. In this situation, various configurations for downlink/uplink control signaling (DL/UL) control signaling) should be considered. For example, in order to support CAs for up to 32 CCs in the PHY and MAC layers, excessive signaling overhead may occur, and such overhead can be reduced through RRC signaling proposed below.

In the present invention, in order to more effectively perform addition or modification to the Scell in a situation in which up to 32 CCs are CA, a method of dividing the serving cells into a maximum of 4 groups and signaling RRC is proposed. Each group may consist of up to 8 CCs, and the base station may set the number of groups to the terminal in consideration of the total number of serving cells and efficiency of radio resource utilization.

Table 1 shows an example of a method in which 25 CCs are divided into 4 groups and configured.

RRC signaling 1st serving cell group (SGC#0 (supports up to 8 CCs)) Second serving cell group (SGC#1 (supports up to 8 CCs)) 3rd serving cell group (SGC#2 (supports up to 8 CCs)) 4th serving cell group (SGC#3 (supports up to 8 CCs)) PCell (self-scheduling) SCell#0 (Cross-carrier scheduling) SCell#0 (Cross-carrier scheduling) SCell#0 (self-scheduling) SCell#1 SCell#1 SCell#1 SCell#1 SCell#2 SCell#2 SCell#2 SCell#2 SCell#3 SCell#3 SCell#3 SCell#3 SCell#4 SCell#4 SCell#4 SCell#4 SCell#5 SCell#5 SCell#5 SCell#5 SCell#6

Referring to Table 1, the number of groups may be determined in consideration of the number of CCs configured in the terminal and the maximum number of CCs that can be set in one group. In the embodiment of Table 1, up to 8 CCs can be set in one serving cell group.

In the embodiment of Table 1, 25 CCs are divided into a total of 4 groups, and the first serving cell group (SCG#0) includes a total of 7 CCs including the PCell. Each of the six SCells has an index from 1 to 6, and the PCell and all SCells operate in self-scheduling. The second serving cell group (SGC#2) and the third serving cell group (SGC#3) include a total of 6 CCs, and cross-carrier scheduling is configured for one specific SCell in each group. The remaining serving cells have indices from 1 to 5. The fourth serving cell group (SCG#3) includes a total of 6 CCs and operates in self-scheduling for all SCells.

In another embodiment, the serving cell group is divided into two groups, and the first serving cell group (SCG#0) includes a PCell and may be composed of up to 16 serving cells, whereas the second serving cell group (SCG#0) includes a PCell. The serving cell group (SCG#1) always includes the SCell in which the PUCCH SCell is configured (if the terminal supports the PUCCH SCell and the base station is configured with the serving cell group configuration), it can be composed of up to 16 serving cells. .

Here, the PUCCH SCell means that the base station sets the PUCCH transmission in addition to the PUCCH transmission (default) of the PCell among SCells to the terminal supporting it. Through this, the UCI (Uplink Control Information) overhead transmitted through the uplink can be offloaded from the PCell to the SCell, thereby leading to system performance improvement.

Meanwhile, the relationship between the serving cell index and the serving cell group may be fixed. For example, in RRC, the index of the total serving cell is 0 to 31, and each serving cell may be allocated up to 8 serving cells per serving cell group within 4 serving cell groups. At this time, the first serving cell group is serving cell indexes 0-7, the second serving cell group is serving cell indexes 8-15, the third serving cell group is serving cell indexes 16-23, and the fourth serving cell group is serving cell indexes 24-31. It has a serving cell index of up to. Of course, this index is only valid at the Radio Resource Control (RRC) layer, and the MAC or PHY layer has a serving cell index in each group, that is, an index of 0 to 7. For example, in the MAC or PHY, the index value corresponding to the serving cell index 1 (SCell #1) in the serving cell group #1 in Table 1 indicates the serving cell index equal to the value of the serving cell index 9 in RRC. I can.

Adding, removing, or reconfiguring a secondary serving cell to a serving cell set is performed through an RRC reconfiguration procedure, which is dedicated signaling. When a new secondary serving cell is added to the serving cell set, the RRC reconfiguration message includes system information on the new secondary serving cell and is transmitted. Therefore, in the case of a secondary serving cell, a monitoring operation for system information change is not required.

According to an aspect of the present invention, the TAG configuration may be independently configured from the serving cell group configuration above. Depending on the deployment scenario and the frequency band, the serving cells belonging to one TAG and the group belonging to the serving cell group as in the embodiment illustrated in Table 1 may be the same or may be different from each other. In addition, the number of TAGs to be used and the number of groups to be served may be independently set and used.

2 shows an example of a structure in which serving cells are grouped for signaling according to an embodiment of the present invention.

Referring to FIG. 2, 32 CCs are divided into 4 serving cell groups, that is, SCG#0, SCG#1, SCG#2, and SCG#3. In FIG. 2, MAC signaling #0 and PHY signaling #0 represent MAC signaling and PHY signaling in SCG#0, and MAC signaling #1 and PHY signaling #1 represent MAC signaling and PHY signaling in SCG#1. Similarly, MAC signaling #2 and PHY signaling #2 represent MAC signaling and PHY signaling in SCG#2, and MAC signaling #3 and PHY signaling #3 represent MAC signaling and PHY signaling in SCG#3.

The method of serving cell grouping according to an embodiment of the present invention can support CA using five or more CCs while minimizing the influence on the PHY/MAC control information signaling format of a conventional wireless communication system using five CCs. have. For example, the present invention provides the following three effects.

1) A 3-bit CIF field size in the DCI format can be maintained.

2) 8-bit activation/deactivation MAC CE field structure can be maintained.

3) The field structure of the 8-bit PHR MAC CE can be maintained.

CIF (Carrier Indication Field) appears to a terminal in which crosscarrier scheduling is configured for a specific SCell through RRC signaling from a base station in a DCI format, and a serving cell for scheduling (E)PDCCH for downlink/uplink transmission of the SCell ( serving cell).

Assuming that serving cell grouping is not applied according to an embodiment of the present invention, when CA is performed, if the maximum number of concatenable CCs increases from 5 to 32, the Carrier Indication Field (CIF) in the DCI format is Cross-carrier scheduling for all CCs can be performed only when it is increased from 3 bits to 5 bits. However, if the size of the CIF increases, not only the PHY structure may be affected, but also the PDCCH (or EPDCCH) link performance may be adversely affected.

Therefore, if the concept of a serving cell group proposed in an embodiment of the present invention is applied, a 3-bit CIF field can be used because CIF is set within one serving cell group. Therefore, it may have less influence on the PHY structure change according to the CIF field and the number of serving cells.

According to an aspect of the present invention, a CIF in a DCI format according to each serving cell group may configure cross-carrier scheduling only within each serving cell group. If the CIF is not configured, it may be determined to perform self-scheduling. These prerequisites can be good prerequisites for UCI enhancement. For example, in a conventional system, the number of serving cells is considered in the size of the HARQ-ACK reporting bit, and the number of HARQ-ACK bits is divided by SCG to obtain a new UCI signaling format or PUCCH on the SCell. Can be transmitted through. In addition, PHY can be effectively designed for CSI, soft-buffer, rate-matching, and power control. In addition, according to the above configuration, it is possible to distribute the overhead of downlink control signaling to a specific serving cell such as a PCell. In addition, it is possible to limit the setting of the PDCCH/EPDCCH search space. In addition, a PHICH is transmitted to a serving cell through which an UL grant signal is transmitted.

According to another aspect of the present invention, when a PCell or a PUCCH SCell is included in one serving cell group, an 8-bit activation/deactivation MAC CE may be applied.

That is, when a CA is configured in the terminal, an activation/deactivation mechanism for the secondary serving cell is supported in order to optimize the battery consumption of the terminal. The activation/deactivation mechanism is based on a combination of a MAC control element (CE) and a deactivation timer. MAC CE represents whether to activate/deactivate each secondary serving cell as one bit, where '0' represents deactivation, and '1' represents activation. The MAC CE can independently indicate whether to activate/deactivate the secondary serving cells through a bit corresponding to each secondary serving cell, which can be configured in the form of a bitmap.

3 shows an example of an activation/deactivation MAC CE structure when a PCell or a PUCCH SCell is included in one serving cell group according to an embodiment of the present invention.

3, the structure of the activation/deactivation MAC CE has a fixed length of 8 bits. In FIG. 3, C ₁ is an indicator indicating activation/deactivation of the SCell having the index value '1' when the SCell having the index value '1' is configured. Similarly, C ₂ is an indicator indicating activation/deactivation of the SCell having the index value '2' when the SCell having the index value '2' is configured. In this case, the terminal may ignore a field for an SCell that is not configured in the terminal. 'R' is a reserved bit and is always set to '0'. It is assumed that the PCell included in the serving cell group is always activated. Likewise, even when a PUCCH SCell is included in a serving cell group, it is assumed that the PUCCH SCell is always activated.

Accordingly, the MAC CE signaling format of the structure shown in FIG. 3 is used for the serving cell group in which the PUCCH SCell is configured. If the PUCCH SCell and other SCells are included in one serving cell group, the index value of the PUCCH SCell is defined as '0'. According to an example of the present invention, when a PUCCH SCell exists in one SCG, this may correspond to the R field.

Regarding the operation of the terminal in the activation/deactivation state, if the secondary serving cell is in the deactivated state, the terminal does not need to receive the PDCCH or PDSCH corresponding to the secondary serving cell, and through the uplink corresponding to the secondary serving cell. No transmission can be made. In addition, CQI (Channel Quality Indicator) measurement should not be performed. Conversely, when the secondary serving cell is in an active state, the UE can receive the PDCCH and PDSCH. However, this is performed only when the corresponding terminal is configured to monitor the PDCCH for the secondary serving cell. In addition, it should be possible to perform CQI measurement operation.

According to another aspect of the present invention, if a PCell or a PUCCH SCell is not included in one serving cell group, and only the remaining SCells are included, a MAC CE having a modified structure may be used.

4 shows an example of an activation/deactivation MAC CE structure when a PCell or a PUCCH SCell is not included in one serving cell group according to another embodiment of the present invention.

4, the structure of the MAC CE has a fixed length of 8 bits. In FIG. 4, C ₁ is an indicator indicating activation/deactivation of the SCell having the index value '1' when the SCell having the index value '1' is configured. Similarly, C ₂ is an indicator indicating activation/deactivation of the SCell having the index value '2' when the SCell having the index value '2' is configured. In this case, the terminal may ignore a field for an SCell that is not configured in the terminal. C ₀ is an indicator indicating activation/deactivation of the SCell having the index value '0' when the SCell having the index value '0' is configured. The MAC CE structure of the format shown in FIG. 4 should be used only when the terminal is configured to support 5 or more CCs and serving cell grouping of the present invention is used. When the PCell or PUCCH SCell is not included in one serving cell group as in the embodiment of FIG. 4, activation/deactivation compared to the case where the PCell or PUCCH SCell is included in one serving cell group as in the embodiment of FIG. There is one more SCell to which is indicated. Therefore, instead of using the'R' field, it is used as an index field for indicating activation/deactivation of one additional SCell.

5 and 6 show an example of an activation/deactivation MAC CE structure in which four serving cell groups are grouped according to an embodiment of the present invention.

5 shows a PCell or a PUCCH SCell is included in a first serving cell group (SGC#0) and a second serving cell group (SGC#1), and a third serving cell group (SGC#2) and a fourth serving cell group ( SGC#3) shows an example of a grouped activation/deactivation MAC CE structure when a PCell or a PUCCH SCell is not included.

Meanwhile, FIG. 6 shows that a PCell or a PUCCH SCell is included in a first serving cell group (SGC#0), a second serving cell group (SGC#1), a third serving cell group (SGC#2), and a fourth serving cell. A group (SGC#3) shows an example of a grouped activation/deactivation MAC CE structure when a PCell or a PUCCH SCell is not included.

According to an aspect of the present invention, a modified MAC CE structure in which a 2-bit data field is added to the MAC CE type as shown in FIG. 3 or 4 may be used. This is as shown in FIG. 7. 7 shows an example of a MAC CE structure according to another embodiment of the present invention.

Referring to FIG. 7, the MAC CE structure may additionally include a 2-bit data field indicating the ID of the serving cell group. In addition, the position of the 2-bit data field may be before _{C 7} or after R, which is an indicator indicating activation/deactivation of an SCell having an index value of '7'. In addition, the data field may be displayed as'SGC id'. Since the number of serving cell groups is up to four, information can be displayed by 2-bit data.

According to an aspect of the present invention, signaling in the form of an extended PHR MAC Control Element (CE) for eight serving cells in one serving cell group may be used. 8 shows an example of an extended PHR MAC CE according to an embodiment of the present invention. The first extended PHR MAC CE structure of FIG. 8 is a structure when a PCell is included in a serving cell group.

Referring to FIG. 8, a first extended PHR MAC CE includes a plurality of octets, and the first octet is a field indicating whether to activate a serving cell corresponding to each of C1 to C7. After that, the second octet consists of a P field, a V field, and a field indicating the type 2 surplus power (PH) for the primary serving cell. After that, the third octet consists of two R fields and a field indicating _{P CMAX,c 1 related to the type 2 surplus power.} After that, the fourth octet consists of a P field, a V field, and a field indicating the type 1 surplus power (PH) for the primary serving cell. After that, the fifth octet consists of two R fields and a field indicating _{P CMAX,c 2 related to the type 1 surplus power.}

9 shows an example of an extended PHR MAC CE according to another embodiment of the present invention. The second extended PHR MAC CE structure of FIG. 9 is a structure when a PCell and a PUCCH SCell are included in a serving cell group.

Referring to FIG. 9, the first octet of the second extended PHR MAC CE is a field indicating whether or not a serving cell corresponding to each of C1 to C7 is activated. Thereafter, the terminal arranges the type 1 and type 2 surplus power and P _CMAX,c information for the PCell, and after that, the terminal is the type for the secondary serving cell in which the PUCCH is configured among serving cells in the serving cell group (SCG). Arrange 1 and type 2 surplus power and P _CMAX,c information, and after that, surplus power and P for the corresponding secondary serving cell in the order of serving cell indexes of the activated secondary serving cells (SCell1,..., SCell n). The second extended PHR MAC CE is configured by arranging _{CMAX information.}

According to an aspect of the present invention, when performing PHR, the terminal provides a value of the serving cell group ID (SCG ID) to the base station by using the reserved bits of the'R' field to indicate which SCG corresponds to the PHR. I can.

10 is a flowchart illustrating a method of transmitting an RRC signal by a base station according to an embodiment of the present invention.

Referring to FIG. 10, the base station first resets the RRC connection (S1010). Adding, removing, or reconfiguring a secondary serving cell to a serving cell set is performed through an RRC reconfiguration procedure, which is dedicated signaling. When a new secondary serving cell is added to the serving cell set, the RRC reconfiguration message includes system information on the new secondary serving cell and is transmitted. The secondary serving cell configuration information may include information on a frequency band and a center carrier to which an unlicensed carrier is allocated. Since this is derived through the EARFCN value, the EARFCN value is included in the secondary serving cell configuration information, so that it is possible to indicate which frequency band and which center carrier the corresponding secondary serving cell corresponds to. Therefore, in the case of the secondary serving cell, it may not be necessary to perform a monitoring operation for the change of system information.

Next, the base station transmits RRC signaling for the CC grouped to the terminal (S1030). Each group may consist of up to 8 CCs, and the number of groups may be determined in consideration of the total number of serving cells and efficiency of radio resource utilization.

The RRC signaling transmitted to the terminal may include an index of a serving cell group and an index of a serving cell within the serving cell group. For example, in RRC, the index of the total serving cell is 0 to 31, and each serving cell may be allocated up to 8 serving cells per serving cell group within 4 serving cell groups. At this time, the first serving cell group is serving cell indexes 0-7, the second serving cell group is serving cell indexes 8-15, the third serving cell group is serving cell indexes 16-23, and the fourth serving cell group is serving cell indexes 24-31. It can have a serving cell index of up to. As an example, the relationship between the serving cell index included in the serving cell group may be mapped (set) differently. Of course, this index is only valid only in Radio Resource Control (RRC), and MAC or PHY has a serving cell index in each group, that is, an index of 0 to 7. For example, in the MAC or PHY, the index value corresponding to the serving cell index 1 (SCell #1) in the serving cell group #1 in Table 1 indicates the serving cell index equal to the value of the serving cell index 9 in RRC. I can.

11 is a flowchart illustrating a method of transmitting a CIF signal by a base station according to an embodiment of the present invention.

Referring to FIG. 11, a base station configures (enabling) a 3-bit CIF in a DCI format for (E)PDCCH transmission for a serving cell in which cross-carrier scheduling is configured through RRC signaling (S1110), and transmits it to the terminal (S1110). S1110).

The serving cells in which the CIF is configured (ie, SCell) may be configured to perform cross-carrier scheduling only within each serving cell group. That is, it means that the serving cell performing scheduling and the serving cell receiving scheduling always belong to the same serving cell group. Here, in the case of a serving cell in which CIF is not configured, self-scheduling is performed.

12 is a flowchart illustrating MAC CE transmission/reception between a base station and a terminal according to an embodiment of the present invention.

Referring to FIG. 12, the base station configures an activation/deactivation MAC CE (S1210) and transmits it to the terminal (S1230). The structure of the activation/deactivation MAC CE has a fixed length of 8 bits. When the PCell and/or PUCCH SCell are included in the serving cell group, the structure of the activation/deactivation MAC CE may be configured as shown in FIG. 3. Meanwhile, when the PCell or PUCCH SCell is included in the serving cell group, the structure of the activation/deactivation MAC CE may be configured as shown in FIG. Meanwhile, as shown in FIG. 5 or 6, an activation/deactivation MAC CE in which four serving cell groups are grouped may be transmitted. Meanwhile, the activation/deactivation MAC CE may further include a 2-bit data field indicating the ID of the serving cell group. 7 shows an example of a MAC CE including a data field indicating an ID of a serving cell group.

Next, the terminal configures an extended PHR MAC Control Element (CE) (S1250) and transmits it to the base station (S1270). The structure of FIG. 8 or 9 may be used for the extended PHR MAC CE. The extended PHR MAC CE when the PCell is included in the serving cell group has a structure as shown in FIG. 8, and the extended PHR MAC CE when the PCell and PUCCH SCell are included in the serving cell group has the structure as shown in FIG. . 8 and 9 are a structure of an extended PHR MAC CE for all serving cells included in one serving cell group.

13 is a block diagram of a terminal and a base station supporting a serving cell group according to the present invention.

Referring to FIG. 13, a terminal 1300 includes an RF unit (radio frequency) unit 1305, a PHR MAC CE processor 1310, and a memory 1315. The memory 1315 is connected to the PHR MAC CE configuration unit 1310 and stores various information for driving the PHR MAC CE configuration unit 1310. The RF unit 1305 is connected to the PHR MAC CE configuration unit 1310 and transmits and/or receives a radio signal. For example, the RF unit 1305 may receive the RRC signaling, CIF, and activation/deactivation MAC CE published herein from the base station 1350.

The PHR MAC CE configuration unit 1310 implements the proposed function, process and/or method. Specifically, the PHR MAC CE configuration unit 1310 performs the steps included in FIG. 12, and the expanded PHR MAC CE configured through the PHR MAC CE configuration unit has a structure as shown in FIG. 8 or 9.

In all embodiments of the present specification, the operation of the terminal 1300 may be implemented by the PHR MAC CE configuration unit 1310.

The memory 1315 stores RRC signaling, CIF, and activation/deactivation MAC CE according to the present specification.

The base station 1350 includes a processor 1355, a memory 1360, and an RF unit 965 (a radio frequency (RF) unit). The memory 1360 is connected to the processor 1355 and stores various information for driving the processor 1355. The RF unit 1365 is connected to the processor 1355 and transmits and/or receives a radio signal. The processor 1355 implements the proposed function, process and/or method. In the above-described embodiment, the operation of the base station may be implemented by the processor 1355. The processor 1355 includes an RRC configuration unit 1356, a CIF configuration unit 1357, and an activation/deactivation MAC CE configuration unit 1358.

The RRC configuration unit 1356 configures the RRC according to the present invention. The RRC signaling configured by the RRC configuration unit 1356 may include an index of a serving cell group and an index of a serving cell within the serving cell group. For example, in RRC, the index of the total serving cell is 0 to 31, and each serving cell may be allocated up to 8 serving cells per serving cell group within 4 serving cell groups. At this time, the first serving cell group is serving cell indexes 0-7, the second serving cell group is serving cell indexes 8-15, the third serving cell group is serving cell indexes 16-23, and the fourth serving cell group is serving cell indexes 24-31. It has a serving cell index of up to.

The CIF configuration unit 1357 configures and transmits a 3-bit CIF to the terminal. When the CIF is configured, serving cells may be configured to perform cross-carrier scheduling only within each serving cell group. If the CIF is not set, it is set to perform self-scheduling.

The activation MAC CE configuration unit 1358 configures an activation/deactivation MAC CE having a fixed length of 8 bits. When a PCell or a PUCCH SCell is included in the serving cell group, the structure of the activation/deactivation MAC CE is shown in FIG. 3. Meanwhile, when a PCell or a PUCCH SCell is included in a serving cell group, the structure of an activation/deactivation MAC CE is as shown in FIG. 4. Meanwhile, activation/deactivation MAC CE in which four serving cell groups are grouped as shown in FIG. 5 or 6 may be transmitted. Meanwhile, the activation/deactivation MAC CE may further include a 2-bit data field indicating the ID of the serving cell group. 7 shows an example of a MAC CE including a data field indicating an ID of a serving cell group.

The processor 1355 may include an application-specific integrated circuit (ASIC), another chipset, a logic circuit, and/or a data processing device. The memory may include read-only memory (ROM), random access memory (RAM), flash memory, memory card, storage medium, and/or other storage device. The RF unit may include a baseband circuit for processing a radio signal. When the embodiment is implemented in software, the above-described technique may be implemented as a module (process, function, etc.) that performs the above-described function. Modules are stored in memory and can be executed by a processor. The memory may be inside or outside the processor, and may be connected to the processor through various well-known means.

According to the present invention, by grouping serving cells in a multi-carrier system, a wireless communication method and apparatus capable of reducing overhead to a primary serving cell (Pcell) is provided. In addition, it is possible to support a plurality of component carriers while minimizing changes to the existing physical layer structure.

Claims (12)

In a method for grouping serving cells of a base station in a multi-component carrier system,
Grouping a plurality of component carriers configured in the terminal;
Transmitting RRC signaling to the terminal; And
Configuring a carrier indicator field (CIF) within one serving cell group and transmitting it to the terminal
Including,
Each of the grouped groups includes a maximum of 8 CCs,
The serving cell in which the CIF is configured performs cross-carrier scheduling only within the serving cell group, and the serving cell in which the CIF is not configured performs self-scheduling. Way.
The method of claim 1, wherein the RRC signaling includes an index of a serving cell group and an index of a serving cell within the serving cell group.
delete The method of claim 1, wherein the CIF has a size of 3 bits.
The method of claim 1, wherein the CIF indicates information on a component carrier set in the terminal within the serving cell group.
The method of claim 1, wherein the method of grouping the serving cells further comprises transmitting an activation/deactivation medium access control (MAC) control element to a terminal.
In a signal reception method in a serving cell grouped by a terminal in a multi-component carrier system,
Receiving RRC signaling from a base station; And
Receiving, from the base station, a carrier indicator field (CIF) configured in one serving cell group
Including,
Each of the grouped groups includes a maximum of 8 CCs,
The serving cell in which the CIF is configured performs cross-carrier scheduling only within the serving cell group, and the serving cell in which the CIF is not configured performs self-scheduling. How to receive signals in cells.
The method of claim 7, wherein the RRC signaling includes an index of a serving cell group and an index of a serving cell within the serving cell group.
delete 8. The method of claim 7, wherein the CIF has a size of 3 bits.
8. The method of claim 7, wherein the CIF indicates information on a component carrier set in the terminal within the serving cell group.
The method of claim 7, further comprising receiving an activation/deactivation medium access control (MAC) control element from a base station.

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