KR102357413B1 - A method for carrier aggregation in a wireless communication system and apparatus thereof - Google Patents

Abstract

According to an embodiment of the present invention, in a macro cell that includes at least one small cell and communicates with FDD, a transceiver that communicates with at least one network node and controls the small cell to communicate with TDD, Device and communication method using the same, comprising a control unit for generating control information to prevent handover from occurring when the UE moves between small cells in the macro cell, and controlling to transmit the control information to the UE provides

Description

Carrier aggregation communication method and apparatus in a wireless communication system {A method for carrier aggregation in a wireless communication system and apparatus thereof}

The present invention relates to a method and apparatus for combining carrier wave communication in a wireless communication system. The present invention relates to a method and apparatus for improving mobility and managing interruption based on a cell state in a carrier-associated system.

In general, mobile communication systems have been developed for the purpose of providing communication while securing user mobility. Such a mobile communication system has reached a stage where it can provide high-speed data communication services as well as voice communication thanks to the rapid development of technology. In recent years, as one of the next-generation mobile communication systems, the 3rd Generation Partnership Project (3GPP) is working on a standard for LTE (Long Term Evolution) / LTE-A (LTE-Advanced) systems. LTE is a technology that implements high-speed packet-based communication with a transmission speed of up to 100 Mbps. Recently, as the types of services using wireless mobile communication systems are greatly diversified, there is a need for new technologies to support new services more efficiently, and accordingly, to improve communication quality based on LTE / LTE-A systems New methods and techniques are being researched for

An object of the present invention is to provide a method and apparatus for efficiently improving communication quality in a wireless communication system. An object of the present invention is to provide a method and an apparatus for improving communication quality based on a state of a cell.

According to an embodiment of the present invention, in a macro cell including at least one small cell, a transceiver performing communication with at least one network node and FDD mode are set for the macro cell, and to the TDD mode, and when the terminal moves between small cells in the macro cell, it generates control information to prevent handover from occurring, and comprises a control unit for controlling to transmit the control information to the terminal device can be provided.

In addition, according to an embodiment of the present invention, in the method for setting carrier aggregation of a macro cell including at least one small cell, setting the macro cell to the FDD mode, and setting the small cell to the TDD mode to provide a method comprising the steps of: generating control information for preventing handover from occurring when the terminal moves between small cells in the macro cell; and transmitting the control information to the terminal can

In addition, according to an embodiment of the present invention, in a terminal communicating with a macro cell including at least one small cell, a transceiver performing communication with at least one network node and control from the macro cell set to the FDD mode It is possible to provide an apparatus comprising: a control unit configured to receive information and not to cause a handover when the terminal moves between the small cells set in TDD based on the control information.

In addition, according to an embodiment of the present invention, in a method of carrier aggregation configuration of a terminal communicating with a macro cell including at least one small cell, the step of receiving control information from the macro cell set to the FDD mode and setting, based on the control information, so that handover does not occur when the terminal moves between the small cells configured in TDD.

In addition, according to an embodiment of the present invention, in the carrier aggregation communication method of a macro cell (PCell, Primary Cell) in a wireless communication system, the step of receiving small cell (SCell, Secondary Cell) related measurement information from the terminal and the measurement Based on the information, it is possible to provide a method comprising the step of determining a user plane transmission in the macro cell.

In addition, according to an embodiment of the present invention, in the apparatus of a macro cell (PCell, Primary Cell) for carrier aggregation communication in a wireless communication system, a small cell (SCell, Secondary Cell)-related measurement information, and based on the measurement information, it is possible to provide an apparatus comprising a control unit for controlling to determine the user plane transmission in the macro cell.

In addition, according to an embodiment of the present invention, in the carrier aggregation communication method of a terminal in a wireless communication system, transmitting measurement information related to a small cell (SCell, Secondary Cell) to a macro cell (PCell, Primary Cell), the measurement Based on the information, receiving an SCell setup message from the macro cell and if the small cell is in the SCell activation state, receiving the user plane from the small cell without receiving the user plane from the macro cell A method characterized in that can be provided.

In addition, according to an embodiment of the present invention, in the apparatus of a terminal for carrier aggregation communication in a wireless communication system, a small cell (PCell, Primary Cell) and a transceiver for communicating with at least one network node SCell, Secondary Cell) related measurement information is transmitted, and an SCell configuration message is received from the macro cell based on the measurement information, and when the small cell is in the SCell activation state, the user plane is not received from the macro cell, It is possible to provide an apparatus comprising a control unit for controlling to receive the user plane from the small cell.

In addition, according to an embodiment of the present invention, in a macro cell including at least one small cell, a transceiver performing communication with at least one network node and the macro cell are set to FDD mode, and the small cell TDD mode is set, and when the terminal moves between the small cells in the macro cell, control information is generated for setting so that handover does not occur, and based on the control information, a control plane is provided to the macro cell and the small cell. and a control unit that separates the user plane and controls whether to transmit the user plane of the macro cell based on the state information of the small cell.

In addition, according to an embodiment of the present invention, in the carrier aggregation communication method of a macro cell including at least one small cell, setting the macro cell to the FDD mode and setting the small cell to the TDD mode, the terminal generating control information for setting that handover does not occur when moving between the small cells in the macro cell; based on the control information, separating a control plane and a user plane into the macro cell and the small cell and determining whether to transmit the user plane of the macro cell based on the state information of the step and the small cell.

In addition, according to an embodiment of the present invention, in a terminal communicating with a macro cell including at least one small cell, between a transceiver for performing communication with at least one network node and the small cell in which the terminal is set to the TDD mode Receives control information for setting so that handover does not occur during movement, separates a control plane and a user plane into the macro cell and the small cell based on the control information, and separates a control plane or a user plane from the macro base station It is possible to provide an apparatus comprising a control unit controlling to receive a plane, wherein reception of the user plane from the macro base station is determined based on SCell activation state information for the small cell.

In addition, according to an embodiment of the present invention, in the carrier aggregation communication method of a terminal communicating with a macro cell including at least one small cell, handover does not occur when the terminal moves between the small cells set in the TDD mode. receiving control information for setting not to be performed, separating a control plane and a user plane into the macro cell and the small cell based on the control information, and receiving a control plane or a user plane from the macro base station Including, reception of the user plane from the macro base station can provide a method, characterized in that determined based on the SCell activation state information for the small cell.

According to an embodiment of the present invention, it is possible to provide a method and apparatus for efficiently improving communication quality in a wireless communication system. According to an embodiment of the present invention, it is possible to provide a method and an apparatus for improving communication communication quality based on a cell state.

In addition, according to an embodiment of the present invention, since high-speed switching is possible without handover when moving between small cells, the mobility of the terminal can be improved. In addition, according to an embodiment of the present invention, it is possible to reduce an interruption when adding a small cell, changing a small cell, or releasing a small cell.

In addition, according to an embodiment of the present invention, the user plane and data plane of the macro cell and the small cell are separately operated to reduce the load of the macro cell and improve radio resource throughput.

1 is a diagram illustrating the structure of an LTE system to which the present invention is applied.
2 is a diagram illustrating a radio protocol structure in an LTE system to which the present invention is applied.
3 is a diagram for explaining carrier aggregation in a terminal.
4 is a diagram illustrating handover in a mobile communication system that does not support carrier aggregation (CA).
5 is a diagram illustrating separation of a control area and a user area according to an embodiment of the present invention.
6 is a diagram for explaining a network environment according to an embodiment of the present invention.
7 is a view for explaining a network operating method according to the first embodiment of the present invention.
8 is a diagram for explaining the operation of a macro base station according to the first embodiment of the present invention.
9 is a view for explaining the operation of the terminal according to the first embodiment of the present invention.
10 is a diagram for explaining a problem when a cell environment is changed in a CA environment of a macro cell and a small cell.
11 is a diagram for explaining a problem in a conventional handover environment.
12 is a view for explaining a network operating method according to a second embodiment of the present invention.
13 is a view for explaining the operation of a macro base station according to the second embodiment of the present invention.
14 is a diagram for explaining an operation of a terminal according to a second embodiment of the present invention.
15 is a diagram for explaining the configuration of a C-RAN eNB according to an embodiment of the present invention.
16 is a view for explaining the configuration of a macro base station according to an embodiment of the present invention.
17 is a diagram for explaining the configuration of a terminal according to an embodiment of the present invention.

Hereinafter, various embodiments will be described in detail with reference to the accompanying drawings. In this case, it should be noted that in the accompanying drawings, the same components are denoted by the same reference numerals as much as possible. In addition, detailed descriptions of well-known functions and configurations that may obscure the gist of the present invention will be omitted. In the following description, only parts necessary for understanding the operation according to various embodiments of the present invention will be described, and it should be noted that descriptions of other parts will be omitted so as not to obscure the gist of the present invention.

In the following embodiment of the present invention, it is assumed that the mobile communication network supports carrier aggregation (CA). In an embodiment of the present invention, it is assumed that the terminal supports carrier aggregation (CA). In this case, the CA supported for the UE may support CA for each of FDD/FDD, TDD/TDD, TDD/FDD, and FDD/TDD. In addition, in CA, a macro cell may be set as a primary cell (PCell) and a small cell may be set as a secondary cell (SCell).

In the case of operating a PCell (Primary Cell) of a mobile communication network supporting CA in FDD and operating a SCell (Secondary Cell) in TDD, as described below, TDD cell coverage is confirmed as described below. However, it should be noted that the embodiments of the present invention described below do not necessarily assume that the PCell is set to FDD and the SCell is set to TDD, and any combination thereof may be applied.

In an embodiment of the present invention, a control plane is a signal for control information. The term "plane" may be used interchangeably with terms such as plane and dimension. Hereinafter, an embodiment of the present invention will be described on the assumption that the above can be used interchangeably.

The control information may include scheduling information, ack/nack information, connection management information, and mobility management information. A user plane is a signal for data information excluding control information. The data information may include VOLTE information and Internet data service information.

In an embodiment of the present invention, the control plane and the user plane split may be referred to as C-U split hereinafter. In C-U separation, the control plane is performed only in the macro cell, and the user plane is separated to be performed in the small cell, macro cell, or small cell/macro cell. In this case, the control plane for the data plane service of the small cell may be transmitted through the macro cell. Therefore, when the terminal moves between small cells in the macro cell in C-U separation, the terminal receives a control signal from the macro cell. A control signal for inter-cell movement is also received through the macro cell.

Hereinafter, the first embodiment and the second embodiment will be separately described for convenience of description, but the first and second embodiments are cell configuration and CU separation for improving communication efficiency in CA of a macro base station and a small base station , and for improving radio resource processing according to a small cell environment, it is obvious that a combination of each embodiment is possible.

1 is a diagram illustrating the structure of an LTE system to which the present invention is applied.

1, as shown, the radio access network of the LTE system is a next-generation base station (Evolved Node B, hereinafter ENB, Node B or base station) (105, 110, 115, 120) and MME (125, Mobility Management Entity) and S-GW (130, Serving-Gateway). A user equipment (User Equipment, hereinafter, UE or terminal) 135 accesses an external network through ENBs 105 to 120 and S-GW 130 .

In FIG. 1, ENBs 105 to 120 correspond to existing Node Bs of the UMTS system. The ENB is connected to the UE 135 through a radio channel and performs a more complex role than the existing Node B. In the LTE system, all user traffic, including real-time services such as VoIP (Voice over IP) through the Internet protocol, are serviced through a shared channel, so status information such as buffer status, available transmission power status, and channel status of UEs A device for scheduling is required, and the ENB (105 to 120) is responsible for this. One ENB typically controls multiple cells. For example, in order to implement a transmission rate of 100 Mbps, the LTE system uses, for example, orthogonal frequency division multiplexing (OFDM) in a 20 MHz bandwidth as a radio access technology. In addition, an Adaptive Modulation & Coding (AMC) method that determines a modulation scheme and a channel coding rate according to the channel state of the terminal is applied. The S-GW 130 is a device that provides a data bearer, and creates or removes a data bearer under the control of the MME 125 . The MME is a device in charge of various control functions as well as the mobility management function for the UE, and is connected to a number of base stations.

2 is a diagram illustrating a radio protocol structure in an LTE system to which the present invention is applied.

2, the radio protocol of the LTE system consists of PDCP (Packet Data Convergence Protocol 205, 240), RLC (Radio Link Control 210, 235), and MAC (Medium Access Control 215,230) in the UE and ENB, respectively. PDCP (Packet Data Convergence Protocol) (205, 240) is in charge of operations such as IP header compression/restore, radio link control (Radio Link Control, hereinafter referred to as RLC) (210, 235) PDCP PDU (Packet Data Unit) ) is reconfigured to an appropriate size and ARQ operation is performed. The MACs 215 and 230 are connected to several RLC layer devices configured in one terminal, and perform operations of multiplexing RLC PDUs into MAC PDUs and demultiplexing RLC PDUs from MAC PDUs. The physical layers 220 and 225 channel-code and modulate upper-layer data, make OFDM symbols and transmit them over a wireless channel, or demodulate and channel-decode an OFDM symbol received through a wireless channel, and deliver to the upper layers. .

3 is a diagram for explaining carrier aggregation in a terminal.

Referring to FIG. 3 , in one base station, multiple carriers are generally transmitted and received over several frequency bands. For example, when a carrier 315 having a center frequency of f1 and a carrier having a center frequency of f3 (310) are transmitted from the base station 305, one terminal uses one of the two carriers in the prior art. was sent and received. However, a terminal having a carrier aggregation capability can transmit and receive data from multiple carriers at the same time. The base station 305 may increase the transmission speed of the terminal 330 by allocating more carriers depending on the situation to the terminal 330 having the carrier aggregation capability.

In a traditional sense, when one forward carrier and one reverse carrier transmitted and received from one base station constitute one cell, carrier aggregation may be understood as a terminal transmitting and receiving data through several cells at the same time. will be. Through this, the maximum transmission speed is increased in proportion to the number of aggregated carriers.

Carrier aggregation technology uses only one carrier between a terminal (UE, hereinafter referred to as a terminal) and a base station (eNB, hereinafter referred to as a base station) in existing communication, and uses a main carrier and one or more subcarriers as a secondary The transmission amount can be dramatically increased by the number of carriers. Meanwhile, in LTE, a primary carrier is called a PCell (Primary Cell), and a sub-carrier is called a SCell (Secondary Cell).

In order to use the above-described transmission wave aggregation technique, additional complexity of controlling the SCell in the PCell occurs. In other words, it is necessary to determine which SCells to use or not to use in the PCell, and when these matters are determined, all matters related to the use and non-use of the corresponding SCell should be controlled. On the other hand, a specific method is also required for activating the SCell. That is, when the SCell activation and deactivation commands are received from the base station, the actual operation needs to be specifically specified.

A method of operating a network by separating a control plane and a user plane according to the first embodiment of the present invention will be described with reference to FIGS. 4 to 9 . In the first embodiment of the present invention, a method of operating a macro cell using a frequency division duplexer (FDD) and a small cell using a time division duplexer (TDD) method in a mobile communication network supporting carrier aggregation will be described.

FDD and TDD have the following advantages and disadvantages. FDD is suitable for services such as voice that generate symmetric traffic. TDD is suitable for a bursty, asymmetric traffic service such as the Internet or data. TDD utilizes the spectrum of the band more efficiently. FDD cannot be used in an environment in which a service provider does not have sufficient bandwidth to provide a required guardband between a transmission channel and a reception channel. TDD is more flexible than FDD in satisfying a user's request for dynamically setting uplink and downlink. In addition, since FDD is mainly a low frequency band, it is disadvantageous in terms of data rate, but advantageous in terms of coverage. Since TDD is mainly a high frequency band, it is disadvantageous in terms of coverage, but advantageous in terms of data rate.

As described above, since TDD and FDD each have advantages and disadvantages, if CA is used between TDD and FDD carriers, operators can use all available spectrum resources, thereby increasing flexibility and high performance gain of the mobile communication system. can be obtained That is, since the FDD and TDD spectrum can be used more flexibly, the resource shortage problem can be alleviated. In addition, the combination of FDD and TDD may be effective in supporting asymmetric traffic.

As described above, since operating FDD and TDD cells together has the aforementioned advantages, the first embodiment of the present invention provides a method for effectively operating CA using FDD and TDD. More specifically, in the first embodiment of the present invention, a method for improving mobility and a method for improving throughput by separating the control plane and the user plane will be described.

In an embodiment of the present invention, by separating the control plane and the control plane, when the UE moves between small cells, it is possible to perform cell switching without performing handover. Through this, the mobility of the terminal and the mobility of the network may be improved. To this end, first, handover will be described.

4 is a diagram illustrating handover in a mobile communication system supporting carrier aggregation (CA) between a macro cell and a small cell.

Handover is a communication technology that enables a subscriber to continue to maintain a service in an existing area even if a subscriber moves to another adjacent cell after leaving the area of a cell currently receiving a service in the area in which he or she is located. It automatically switches the current call channel when moving between sectors within a serviced cell or moving from one cell to another. of handover should be performed. Since radio resource control reconfiguration (RRC reconfiguration) of a higher layer is required during handover, temporary interruption may occur even when soft handover is applied.

The handover type can be divided into intra-cell handover, inter-cell handover, and the like, according to a range in which handover occurs.

The intra-cell handover can be referred to as a softer handover performed inside a cell, and refers to changing a channel currently in use within the cell coverage area where the terminal is located. At most inter-sector boundaries, many signals overlap. A terminal passing through this area makes a call through two sectors, which is referred to as a softer handover. That is, since the transmit/receive signal is performed within one base station, the final modem is a handover process.

Handover between cells is generally referred to as soft handover, and is a connect before break method. That is, it means establishing a connection with a new base station before disconnecting from the previous base station. In this case, an efficient technique is required to reduce handover delay and cell loss due to connection re-establishment and release of an existing connection. Inter-cell handover refers to a method of continuing existing communication through a new base station when the mobile terminal cannot continue the connection because it leaves the cell boundary of the serving base station.

Referring to FIG. 4 , the mobile communication system may include a macro cell 410 and a plurality of small cells 420 and 430 included in the coverage of the macro cell. The coverages between the plurality of small cells may be configured to overlap with each other or may be configured to not overlap with each other. The macro cell 410 is operated by FDD, and the small cells 420 and 430 are operated by TDD.

The terminal 400 may perform communication within the range of the macro cell 410 . Assuming that the mobile communication system of FIG. 4 does not support carrier aggregation (CA) of the macro cell 410 and the small cells 420 and 430, the terminal 400 is outside the small cell coverage within the coverage of the small macro cell. When located in , the terminal 400 may receive a control signal and a data signal from the macro cell 410 base station. When the terminal 400 is located in the small cell 420, 430 coverage area, the terminal may perform inter frequency handover to the small cell base station to receive a control signal and a data signal from the small cell base station. Since the macro cell 410 and the small cells 420 and 430 each provide a control region to the terminal, the movement of the terminal between the macro cell/small cell, small cell/small cell, and small cell/macrocell is inter-cell handover (inter-cell). cell handover).

When handover is performed in this way, temporary signal interruption occurs, which is a factor impeding network mobility. Accordingly, there is a need for a method capable of improving mobility without causing handover when moving within a macro cell.

5 is a diagram illustrating separation of a control area and a user area according to an embodiment of the present invention. The cell configuration of FIG. 5 is the same as that described with reference to FIG. 4 . Referring to FIG. 5 , it can be seen that a control plane and a user plane are separated according to the C-U separation. When the terminal 500 is outside the coverage of the small cells 520 and 530 , the terminal 500 receives a control plane and a user plane service from the macro cell 510 . When the UE moves to the coverage of the small cells 520 and 530, it may receive a service from the small cell through the CA. At this time, according to the C-U separation, only the user plane is serviced from the small cells 520 and 530 . When in the small cell coverage, the terminal may or may not receive the user plane service from the macro base station. In case of receiving user area service from macro base station and small cell base station at the same time in small cell coverage, if real-time service is important, such as VOLTE, set to receive user area service from macro cell, and in case of general data service, small cell It is advantageous to enable high-speed service using

When a network is configured and operated as shown in FIG. 5 , both advantages of FDD and TDD can be shared in the system. That is, the control functions such as connection management and mobility management are performed only in the macro FDD PCell layer, the PUCCH of the TDD SCell is transmitted through the uplink of the FDD PCell, and the PUSCH of the TDD SCell is not transmitted. FDD-TDD CA can be operated. That is, by operating the TDD SCell in downlink only mode, it is possible to extend the coverage of the TDD SCell. As a result, the off-loading ratio of the TDD SCell is increased, and the area where TDD-FDD CA is possible is expanded, thereby further increasing the downlink throughput.

The TDD-FDD CA operation scenario as described above can be applied not only to a scenario in which the FDD PCell and the TDD SCell are co-located to a macro or a small cell, but also to a HeNet scenario in which the FDD PCell and the TDD SCell are not co-located.

6 is a diagram for explaining a network environment according to an embodiment of the present invention. Referring to FIG. 6 , there is a Coordination Radio Access Network (C-RAN) entity that manages the entire macro cell 610 and the small cells 620 and 630 . The macro base station 615 managing the macro cell and the small cell base stations 625 and 635 managing the small cell are connected to the C-RAN 600 through a wired network. C-RAN refers to a network in which a scheduler capable of scheduling a macro cell and a scheduler capable of scheduling a small cell are located in the same base station (eNB) and can be adjusted in real time, and can perform CA.

Measurement information (MR, measurement report) received from the terminal may be received from the C-RAN, and through this, it may be determined whether a service for the user plane is possible by the small cell. According to the determination result, when the terminal is located within the small cell coverage, it is possible to provide a service through C-U separation, and when it is outside the small cell coverage, it is possible to receive the service for the control plane and the data plane from the macro base station.

7 is a view for explaining a network operating method according to the first embodiment of the present invention. Referring to FIG. 7 , the network may include a terminal 710 , a macro cell 710 , and a small cell 730 . The small cell may be plural.

In step 761 , the terminal 710 and the macro cell 730 may perform wireless connection and communicate. When the terminal is located in the macro cell coverage rather than the small cell coverage, the terminal may receive a service for the control plane and the user plane from the macro cell 730 .

In step 763 , the macro cell 730 may transmit a control message to the terminal 710 . RRC signaling may be used to transmit the control message. The control information may include information instructing to add the SCell in relation to the CA. Alternatively, according to another embodiment of the present invention, the RRC signaling may further include C-U separation control related information.

The macro cell 730 may transmit a control message on whether to add or release the SCell based on measurement information received from the terminal. The C-U separation related control information may be control information indicating that a macro cell (PCell) operated by FDD serves the control plane, and a small cell (SCell) operated by TDD serves only the data plane.

In this case, the control information for the small cell (SCell) may be transmitted to the terminal 710 through the PCell. That is, the terminal 710 may receive the control signal for the macro cell and the control signal for the small cell through the control plane of the PCell. Indicating that the small cell only serves the data plane does not indicate that the macro cell cannot service the data plane. When the small cell serves only the data plane, it indicates that the small cell does not service the control plane.

When the control message includes the SCell addition message, in step 765 , the macro cell 730 may transmit an activation control message to the terminal 710 . The activation control message may be transmitted in the form of MAC CE. Upon receiving the activation control message, the UE may activate the SCell corresponding to the message.

Thereafter, in steps 767 and 769, communication through C-U separation may be performed according to the received control message. That is, the control functions such as connection management, mobility management, and scheduling related messages are performed in the macro FDD PCell layer (step 767). In this case, the data plane may not exist in the FDD PCell layer. TDD-FDD CA is operated so that the PUCCH of the TDD SCEll is transmitted through the FDD PCell uplink and the PUSCH of the TDD SCell is not transmitted. The TDD SCell may extend the coverage of the TDD SCell by operating only the downlink mode (step 769). Communication in steps 767 and 769 is communication in a state in which the C-U is separated.

During CA operation of the macro cell 730 and the small cell 750 , the UE may go out of the small cell coverage. The macro cell 730 may release the small cell from the secondary cell based on the measurement information received from the terminal.

In step 771 , a control message may be transmitted to the terminal 710 in the macro cell 730 step. The control message may include indication information instructing to release the SCell. The UE may deactivate the SCell based on the release message. The connection between the terminal 710 and the small cell 750 may be released.

In step 775, the macro cell 730 and the terminal 710 may perform communication using the PCell. (This is an assumption when the UE does not enter another small cell coverage after leaving the coverage of the small cell 750. If the UE enters into another small cell coverage, SCell switching or SCell additional control message according to the SCell message It is obvious that the data plane service can be received from .) The small cell 750 stops the data plane service.

8 is a diagram for explaining the operation of a macro base station according to the first embodiment of the present invention. Referring to FIG. 8 , in step 810, the macro cell performs wireless connection with the terminal.

In step 820, the macro cell may transmit a control message to the terminal. RRC signaling may be used to transmit the control message. The control information may include information indicating to add or release the SCell in relation to the CA. According to another embodiment of the present invention, the RRC signaling may further include C-U separation control related information, but is not limited thereto. The macro cell may transmit a control message on whether to add or release the SCell based on measurement information received from the UE. The C-U separation related control information may be control information indicating that a macro cell (PCell) operated by FDD serves the control plane, and a small cell (SCell) operated by TDD serves only the data plane.

In step 830, the macro cell may transmit an activation/deactivation control message. The activation/deactivation control message may be determined based on the control message transmitted in step 820 . If the control message includes SCell add control information in step 820, the macro cell transmits an activation control message to the terminal in step 830. The activation control message is a message instructing the UE to activate the SCell. If the control message includes SCell release control information in step 820, the macro cell transmits a release control message to the terminal in step 830. The release control message is a message instructing the UE to stop the SCell activation and release the SCell from the CA.

In step 840, the macro cell may communicate with the terminal based on C-U separation. That is, the control plane may be transmitted/received to the UE through the FDD PCell layer of the macro cell. The control plane may include information related to connection management, mobility management, and scheduling of the terminal. TDD-FDD CA is operated so that the PUCCH of the TDD SCell is transmitted through the FDD PCell uplink through the FDD PCell layer of the macro cell and the PUSCH of the TDD SCell is not transmitted. In this case, the TDD SCell performing the CA operation with the macro cell operates only in the downlink data mode, thereby extending the coverage of the TDD SCell.

9 is a view for explaining the operation of the terminal according to the first embodiment of the present invention.

Referring to FIG. 9 , in step 910, the terminal performs wireless connection with the macro cell.

In step 920, the terminal may receive a control message from the macro cell. RRC signaling may be used to receive the control message. The control information may include information indicating to add or release the SCell in relation to the CA. According to another embodiment of the present invention, the RRC signaling may further include C-U separation control related information, but is not limited thereto. The control information received by the terminal may include information indicating whether to add or release the SCell. This may be determined based on a measurement report that the terminal transmits to the base station. The C-U separation related control information may be control information indicating that a macro cell (PCell) operated by FDD serves the control plane, and a small cell (SCell) operated by TDD serves only the data plane.

The UE may determine whether to add or release the SCell based on the control information received from the macro cell, and may configure to perform communication through C-U separation during CA of the macro cell and the small cell.

In step 930, the terminal may receive an activation/deactivation control message. The activation/deactivation control message may be determined based on the control message received in step 920 . If the control message includes SCell add control information in step 920, the macro cell transmits an activation control message to the terminal. If the control message includes SCell release control information in step 920, the macro cell transmits a release control message to the terminal.

In step 940, the UE may perform communication with the UE based on the CU separation of a macro cell (FDD-based PCEll) and a small cell macro cell based on CU separation. That is, the UE may transmit/receive the control plane through the FDD PCell layer of the macro cell. The UE receives the PUCCH of the TDD SCell through the FDD PCell layer of the macro cell and performs communication using the TDD-FDD CA so that the PUSCH of the TDD SCell is not received. In this case, the TDD SCell performing the CA operation with the macro cell operates only in the downlink data mode with the UE, through which the coverage of the TDD SCell can be extended.

A second embodiment of the present invention relates to a method and an apparatus for improving communication quality when a small cell environment is changed in a network system that supports CA of a macro cell and a small cell and supports C-U separation. In the second embodiment, the macro cell and the small cell may support all cases in which cells are configured with FDD/FDD, TDD/TDD, FDD/TDD, and TDD/FDD. In the second embodiment of the present invention, when the small cell environment is changed, an indidator is used to control the macro base station to transmit the user plane, and even when the small cell environment is changed, communication quality due to interruption is lowered. A method and apparatus are provided for preventing this from happening. The contents of the handover and C-U separation described in the first embodiment may be applied to the second embodiment, and a description overlapping with the first embodiment will be omitted.

Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. 10 to 14 .

10 is a diagram for explaining a problem when a cell environment is changed in a CA environment of a macro cell and a small cell. Referring to FIG. 10 , a wireless communication network may include a macro cell 1010 and at least small cells 1030 and 1050 . It is assumed that the network of FIG. 10 is a case in which C-U separation is applied in a carrier aggregation (CA) situation.

When the terminal 1000 is located within the small cell coverage, the radio resource throughput is good when the terminal is located in a close distance from the small cell base station or in an area where the channel state of the small cell is good. However, if the mobile station moves to the small cell edge and moves away from the small cell base station or the terminal is located in an area where the channel state of the small cell is not good, the radio resource throughput is not good.

In addition, in the case of CA or dual connectivity of the macro cell and the small cell, the load is high because the macro base station always services the control plane and the user plane of the terminal. Therefore, there is a need for a method to reduce the load on the macro cell.

11 is a diagram for explaining a problem in a conventional handover environment. Referring to FIG. 12 , in a state in which the terminal and the base station are wirelessly connected, the terminal and the base station may perform communication. In step 1110, the base station may receive a measurement report (MR, Measurement Report) from the terminal. The measurement report is that the UE reports cell measurement results for a serving cell and a neighbor cell. The measurement report may use RRC signaling.

The base station may determine handover based on the measurement report received from the terminal. When the UE newly enters the small cell, inter-frequency handover may be performed when the UE departs from the small cell and enters a new small cell. In addition, when the terminal moves to a small cell, inter frequency handover may be performed. During handover, an interruption in which data transmission is impossible for several millimeters may occur.

In the second embodiment of the present invention, based on the edge of the small cell, the small cell channel environment, the user plane scheduling capability of the small cell, etc., it is determined that the small cell cannot process data or cannot process it well, In this case, the macro cell provides a service for the user plane. To this end, indication information or an indicator for turning on/off the user plane of the macro cell for the terminal or turning on/off the user plane of the small cell for the terminal may be used. In addition, handover can be prevented when moving in a small cell through C-U separation, and high-speed cell switching can be used. In addition, it is possible to reduce the load of the macro base station through the C-U separation.

12 is a view for explaining a network operating method according to a second embodiment of the present invention. Referring to FIG. 12 , a wireless communication network may include a terminal 1210 and a base station 1230 (eNB). The base station 1230 may be a C-RAN eNB. For the relationship between the C-RAN eNB and the macro cell and the small cell, refer to FIG. 6 . A macro cell and a C-RAN eNB may be mixed and used. The base station 1230 may include a macro cell 1231 , a small cell 1 1232 , a small cell 2 1233 , a controller 1234 , and an RRC controller 1235 . The controller 1234 and the RRC controller 1235 do not necessarily operate separately, and may be configured as one eNB controller including the controller 124 and the RRC controller 1235 . According to the C-U separation, the control plane is serviced only through the macro base station. Accordingly, in FIG. 12 , an operation in which the user plane is serviced in some cases will be mainly described.

In step 1241, the UE is located within the coverage of the macro cell and not in the coverage of the small cell. The macro cell 1231 may transmit a user plane (data transmission) to the terminal 1210 . In addition, the terminal and the macro cell may perform communication. When the terminal and the macro base station communicate, the terminal periodically or aperiodically measures the radio environment of the serving cell and the adjacent cell, and may transmit a measurement report (MR) to the base station 1230 . Measurement report may use RRC signaling.

In step 1250, the UE enters into the coverage of the small cell 1 1232 according to the cell measurement result. When the terminal 1210 enters the coverage of the small cell 1 1232 , the base station 1230 may transmit an SCell setup message to the terminal 1210 in step 1251 . In step 1253 , the macro cell 1231 transmits an SCell activation message to the terminal 1210 . In step 1254 , the macro cell 1231 transmits indication information indicating that the small cell 1 is capable of data scheduling as an SCell to the controller 1234 .

In step 1258, the controller may enable the SCell to provide a user plane to the terminal based on the indication information. In this case, the controller may set the PCell not to provide the user plane. That is, when the UE can receive the user plane scheduled from the SCell, the PCell may not provide the user plane, thereby reducing the load on the PCell.

In step 1259 , the small cell 1 1233 may transmit a user plane to the terminal 1210 . Still, the control plane may be transmitted to the terminal through the macro cell. A control channel for the user plane transmitted by the small cell may also be serviced through the macro cell.

Step 1260 describes a procedure for changing the SCell when the UE moves between small cells. When the UE moves in a small cell, when moving between cells in which small cell coverage overlaps, an SCell change procedure is performed. When the small cell coverage moves between non-overlapping small cells, a procedure of adding (add) to a new small cell is performed after releasing from the receiving small cell. Step 1260 is an SCell change process. Meanwhile, in each embodiment of the present invention, a process of moving an SCell without performing a handover according to C-U separation when moving a small cell is also called SCell switching. In step 1260 , the terminal 1210 moves from the coverage of the small cell 1 1232 to the coverage of the small cell 2 1233 .

In step 1261, when the small cell 1 1232 cannot transmit the user plane, the base station 1230 controls the small cell 1 non-schedulable indication indicating that the user plane can no longer be scheduled. It can be sent to (1234). In step 1263, the base station 1230 may transmit a message instructing to change the SCell to the terminal 1210 based on the indication information.

In step 1264 , the controller of the base station 1230 may set not to transmit the user plane to the small cell 1 1232 , and may set the macro cell 1231 to transmit the user plane at the same time. The small cell 1 1232 is in an inactive state as an SCell and cannot transmit a user plane, and in step 1265 , the macro cell 1231 may transmit a user plane. As described above, since the base station 1230 knows the cell change timing, when the scheduling possibility of the SCell is changed, the macro cell 1231 can transmit the user plane, thereby preventing a data hole from occurring.

In step 1266, the macro cell transmits an SCell activation message to the terminal, and in step 1267, the macro cell may transmit indication information indicating that the small cell 2 1233 is capable of user plane scheduling to the base station 1230 controller. In step 1268 , the base station 1230 may set the small cell 2 1233 to transmit the user plane to the terminal 1210 based on the indication information. In addition, it may be set so that the macro cell 1231 does not transmit the user plane. In step 1269, the small cell 2 1233 may transmit a user plane to the terminal.

Step 1270 is a diagram for explaining a process of releasing the SCell when the UE leaves the coverage of the small cell 2 1233 among the CAs of the macro cell 1231 and the small cell 1233 .

In step 1271, when the small cell 2 1233 cannot transmit the user plane, the base station 1230 controls the small cell 2 non-schedulable indication indicating that the user plane can no longer be scheduled. It can be sent to (1234). In step 1273, the base station 1230 may transmit a message instructing SCell release to the terminal 1210 based on the indication information.

In step 1274 , the controller of the base station 1230 may set the small cell 2 1233 not to transmit the user plane, and set the macro cell 1231 to transmit the user plane at the same time. Small cell 2 1233 is an SCell in an inactive state and cannot transmit a user plane. In operation 1275, the macro cell 1231 may transmit a user plane. As described above, since the base station 1230 knows the cell release timing, when the SCell cannot schedule the user plane, the macro cell 1231 can transmit the user plane, thereby preventing a data hole from occurring.

When the terminal 1210 moves to the coverage of another small cell within the coverage of the macro cell 1231 after step 1270, it may operate according to the SCell addition operation described in step 1250.

13 is a view for explaining the operation of a macro base station according to the second embodiment of the present invention.

Referring to FIG. 13, in step 1310, the terminal and the macro base station establish a wireless connection and perform wireless communication. In step 1320, while performing wireless communication, the macro base station may receive a measurement report (MR) from the terminal. The macro base station may receive the SCell-related MR when the terminal enters, changes, and leaves the small cell.

In step 1330, the macro base station may perform RRC reconfiguration. The macro base station may transmit an RRC reconfiguration message to the terminal. RRC reconfiguration may be determined based on a measurement report received from the terminal. RRC reconfiguration may include SCell change (SCell change), SCell addition (SCell add), and SCell release (SCell release). According to the contents of RRC reconfiguration, a message requesting SCell addition, release, or change may be transmitted to the terminal.

In step 1340, the macro base station determines whether the SCell, which is the target of RRC reconfiguration, can schedule the user plane, that is, data. Determining whether the user plane can be scheduled does not mean that the SCell transmits scheduling control information for transmitting the user plane, but determines whether the SCell is a cell environment capable of transmitting the user plane. Scheduling is possible in the SCell activation state. SCell activation is possible in SCell add state. Scheduling is not possible in the SCell deactivation state. The SCell release state is always in the SCell deactivation state, and scheduling is not possible. Even in the SCell add state, if the SCell channel state is not good, the SCell can be deactivated. In case of changing the SCell, since the add process is performed after release, the SCell deactivation state may occur. Whether to transmit the user plane through the PCell or the SCell may be determined according to whether the SCell is schedulable. Whether the SCell can schedule the user plane may be determined using scheduling information of the scheduler. For example, based on the SCell scheduling information even in the SCell add and the active state, if the channel state of the SCell is not good, it may be determined that user plane scheduling through the SCell is impossible.

If the SCell can schedule the user plane, it proceeds to step 1350 and may transmit data through the SCell. At this time, the user plane transmission through the PCell may be stopped.

The case in which the SCell can schedule the user plane may be a case in which the terminal moves to the coverage of a new SCell through SCell addition or SCell change. If the SCell cannot schedule the user plane, the process proceeds to step 1360 and data may be transmitted through the PCell. When the SCell cannot schedule the user plane, it may be the case of releasing the SCell or the process of moving from the serving SCell to another SCell during the SCell change process. Since the macro base station can know the scheduling state of the SCell in advance, when the SCell cannot schedule the user plane, the PCell transmits the user plane so that communication can be performed without data interruption.

When the terminal and the base station are continuously operating, each of the above steps may be repeatedly performed.

14 is a diagram for explaining an operation of a terminal according to a second embodiment of the present invention.

14, in step 1410, the terminal and the macro base station establish a wireless connection and perform wireless communication. In step 1420, while performing wireless communication, the terminal may periodically or aperiodically or aperiodically transmit a cell measurement report (MR) to the macro base station. The macro base station may transmit an RRC reconfiguration message based on the measurement report transmitted by the terminal.

In step 1430, the terminal may receive an RRC reconfiguration (RRC reconfiguration) message from the macro base station. RRC reconfiguration may be determined based on a measurement report received from the terminal. RRC reconfiguration may include SCell change (SCell change), SCell addition (SCell add), and SCell release (SCell release).

In step 1440, the UE may activate or deactivate the SCell based on the RRC reconfiguration message. When SCell is added, SCell is activated, and when SCell is released, SCell is deactivated. In case of SCell change, SCell can be activated after SCell deactivation.

In step 1450, the terminal may receive a user plane from a macro base station or a small base station. When the SCell is activated and connected to the small base station in step 1440, a user plane may be received from the small base station. At this time, the PCell may stop user plane transmission.

If the SCell is deactivated in step 1440, it cannot be connected to the small base station and can receive a control plane and a user plane from the PCell. When the SCell is changed in step 1440, the user plane is received from the PCell at the same time as the SCell is deactivated. At this time, it is possible to stop receiving the user plane from the PCell.

It is obvious that the first embodiment can be applied to the second embodiment, and the second embodiment can also be applied to the first embodiment. When the first embodiment is applied to the second embodiment, it is not necessary to specify each cell as an FDD/TDD band. When the second embodiment is applied to the first embodiment, a macro cell may be set as an FDD primary cell and a small cell may be set and applied as a TDD secondary cell.

15 is a diagram for explaining the configuration of a C-RAN eNB according to an embodiment of the present invention.

The C-RAN eNB 1500 is a base station that supports CA of a macro cell and a small cell, and includes a scheduler for a macro cell and a scheduler for a small cell in one base station, so that real-time coordination is possible.

The C-RAN eNB 1500 may include a controller for controlling overall functions of the eNB, a macro cell radio unit 1550 , and a small cell radio unit 1570 . There may be a plurality of small cell wireless units 1570 .

The macro cell radio unit 1550 is an interface through which the macro cell can transmit and receive radio resources to and from the terminal. The control plane and the user plane may be transmitted to the terminal through the macro cell radio unit 1550 . The small cell radio unit 1570 is an interface through which the small cell can transmit and receive radio resources to and from the terminal. The user plane may be transmitted to the terminal through the small cell radio unit 1570 .

The controller controls the overall operation of the eNB. The controller may include an RLC 1510 , an RRC 1513 , a downlink traffic controller 1515 , an SCell active state controller 1517 , and a scheduler 1530 . The scheduler 1530 may include a PCell scheduler 1531 and an SCell scheduler 1533 .

When the SCell is activated, the downlink traffic controller 1515 may control to transmit downlink data only to the SCell and not to transmit data to the macro cell. When the SCell is deactivated, it is possible to control the transmission of DL data to the PCell immediately, thereby preventing the interruption of data transmission when the scheduling environment of the small cell changes.

The SCell activation state control unit 1517 may determine the current SCell activation state and inform the downlink traffic control unit 1515 . The SCell active state controller 1517 may manage the state of the SCell based on the PCell/SCell scheduler or RRC information. In this case, an SCell activation indicator may be used. As an example of the indicator, a SCell activation/deactivation message may be transmitted. In addition, when a preset time elapses after the time of transmitting the RRC message requesting addition, release, or change of the SCell, it may be set to determine whether to schedule the SCell.

Although the configuration of the eNB has been described in blocks, this is for convenience of description and the scope of the present invention is not limited thereto. In addition, it is obvious that the eNB can perform the embodiment of the present invention described with reference to FIGS. 1 to 14 .

16 is a view for explaining the configuration of a macro base station according to an embodiment of the present invention.

Referring to FIG. 16 , the macro base station 1600 includes a transceiver 1610 including a wired interface and a wireless interface, and a controller 1630 for controlling overall operations of the macro base station. The transceiver 1610 may communicate with at least one network node.

According to an embodiment of the present invention, when the macro cell performs FDD communication, the small cell performs TDD communication, and the terminal moves between small cells in the macro cell, control information for preventing handover from occurring and control to transmit the control information to the terminal.

In this case, the control information may be used to configure the terminal to receive a control plane from a macro cell when the terminal moves between the small cells. In addition, the control information may be used to configure the terminal to receive only the user plane from the small cell, and to set the terminal to receive the control plane for the macro cell and the control plane for the small cell from the macro cell. have.

Also, the controller 1630 may receive small cell (SCell, Secondary Cell) related measurement information from the terminal, and control to determine user plane transmission in the macro cell based on the measurement information. The controller (1630) stops the user plane transmission of the macro cell when the small cell is in the SCell active state in the terminal, and controls to transmit the user plane in the macro cell when the small cell is in the SCell inactive state in the terminal can

In addition, the controller 1630 may control the macro cell to transmit the user plane between the SCell deactivation time for cell change and the SCell activation time when the terminal changes the SCell between small cells.

Also, when the user plane throughput of the small cell to the terminal is less than or equal to a preset threshold value, the controller 1630 may control the macro cell to transmit the user plane.

In addition, the control unit 1630 controls the macro cell to perform FDD communication and the small cell to perform TDD communication, and sets the terminal so that handover does not occur when moving between the small cells in the macro cell. generates control information for, based on the control information, separates a control plane and a user plane into the macro cell and the small cell, and determines whether or not to transmit the user plane of the macro cell based on the state information of the small cell control to decide.

Although the configuration of the macro base station has been described in blocks, this is for convenience of description and the scope of the present invention is not limited thereto. In addition, it is obvious that the macro base station can perform the embodiment of the present invention described with reference to FIGS. 1 to 14 .

17 is a diagram for explaining the configuration of a terminal according to an embodiment of the present invention.

Referring to FIG. 17 , a terminal 1700 may include a transceiver 1710 for communicating with at least one network node and a controller 1730 for controlling overall operations of the terminal 1700 .

The controller 1730 may receive control information from the macro cell set to the FDD mode, and may set the terminal so that handover does not occur when the terminal moves between the small cells set in the TDD mode based on the control information.

In this case, the control information may be used to configure the terminal to receive a control plane from a macro cell when the terminal moves between the small cells. In addition, the control information may be used to configure the terminal to receive only the user plane from the small cell, and to set the terminal to receive the control plane for the macro cell and the control plane for the small cell from the macro cell. have.

In addition, the control unit 1730 transmits measurement information related to a small cell (SCell, Secondary Cell) to a macro cell (PCell, Primary Cell), and receives an SCell configuration message from the macro cell based on the measurement information, When the small cell is in the SCell activation state, it is possible to control to receive the user plane from the small cell without receiving the user plane from the macro cell.

In addition, the controller 1730 may control the terminal to receive the user plane from the macro cell between the SCell deactivation time for cell change and the SCell activation time when the terminal changes the SCell between small cells.

Also, when the user plane throughput of the small cell for the terminal is less than or equal to a preset threshold, the controller 1730 may control to receive the user plane from the macro cell.

In addition, when the control unit 1730 communicates with a macro cell including at least one small cell, when the terminal moves between the small cells set in the TDD mode, control information for setting that handover does not occur, and , based on the control information, it is possible to separate a control plane and a user plane into the macro cell and the small cell, and control to receive a control plane or a user plane from the macro base station. In this case, the reception of the user plane from the macro base station may be determined based on SCell activation state information for the small cell.

Although the configuration of the terminal has been described in blocks, this is for convenience of description and the scope of the present invention is not limited thereto. In addition, it is obvious that the terminal can perform the embodiment of the present invention described with reference to FIGS. 1 to 14 .

In addition, the embodiments disclosed in the present specification and drawings are merely provided for specific examples to easily explain the contents of the present invention and help understanding, and are not intended to limit the scope of the present invention. Therefore, the scope of the present invention should be construed as including all changes or modifications derived based on the technical spirit of the present invention in addition to the embodiments disclosed herein are included in the scope of the present invention.

Claims (30)

In the apparatus of a macro cell supporting carrier aggregation for a terminal between at least one small cell, the macro cell performs frequency division duplex communication with the terminal, and the at least One small cell performs time division duplex communication with the terminal within the coverage range of the macro cell,
a transceiver for performing communication with the terminal through a control plane and a first user plane; and
When the terminal is located within the coverage of a first small cell among the at least one small cell, the control plane to the terminal while user data is transmitted to the terminal through a second user plane for the first small cell Controls the transceiver to transmit control data through
Confirming that the terminal moves out of the coverage of the first small cell,
Control indicating that the user data is transmitted to the terminal through the first user plane of the macro cell while the terminal is outside the at least one small cell included within the coverage range of the macro cell a control unit for generating information and controlling the transceiver to transmit the control information to the terminal; includes,
When the terminal is located within the coverage of the first small cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated;
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated device to do.
According to claim 1, wherein the control information,
When the terminal moves from the first small cell to a second small cell among the at least one small cell, the terminal is configured to receive data for the control plane from the macro cell.
According to claim 1, wherein the control information,
The terminal is configured to receive only the data for the user plane from the at least one small cell, and the terminal is configured to receive the data for the first control plane related to the macro cell from the macro cell and the data related to the at least one small cell and configure to receive data for the second control plane.
In the method of a macro cell supporting carrier aggregation for a terminal between at least one small cell, the macro cell performs frequency division duplex communication with the terminal, and the at least One small cell performs time division duplex communication with the terminal within the coverage range of the macro cell,
performing communication with the terminal through a control plane and a first user plane;
When the terminal is located within the coverage of a first small cell among the at least one small cell, the control plane to the terminal while user data is transmitted to the terminal through a second user plane for the first small cell transmitting control data through
confirming that the terminal moves out of the coverage of the first small cell;
Control indicating that the user data is transmitted to the terminal through the first user plane of the macro cell while the terminal is outside the at least one small cell included within the coverage range of the macro cell generating information; and
transmitting the control information to the terminal; includes,
When the terminal is located within the coverage of the first small cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated How to.
According to claim 4, wherein the control information,
When the terminal moves from the first small cell to a second small cell among the at least one small cell, the method characterized in that it is configured to receive data for the control plane from the macro cell.
According to claim 4, wherein the control information,
The terminal is configured to receive only the data for the user plane from the at least one small cell, and the terminal is configured to receive the data for the first control plane related to the macro cell from the macro cell and the data related to the at least one small cell and configuring to receive data for the second control plane.
In a terminal supporting carrier aggregation between at least one small cell and a macro cell, the macro cell performs frequency division duplex communication with the terminal, and the at least one small cell includes Performs time division duplex communication with the terminal within the coverage range of the macro cell,
a transceiver for communicating with the macro cell through a control plane of the macro cell and a first user plane of the macro cell; and
When the terminal is located within the coverage of a first small cell among the at least one small cell, while receiving user data through a second user plane for the first small cell, from the macro cell through the control plane receive control data;
Instruct, from the macro cell, that the user data is transmitted through the first user plane of the macro cell while the terminal is outside the at least one small cell included within the coverage range of the macro cell Receive control information to
a control unit controlling the transceiver to receive data for the user plane through the first user plane of the macro cell based on the control information while the terminal is outside the coverage of the first small cell; including,
When the terminal is located within the coverage of the first small cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated terminal that does.
The method of claim 7, wherein the control information,
The terminal is configured to receive only the data for the user plane from the at least one small cell, and the terminal sets the data for the first control plane related to the macro cell and the at least one small cell from the macro cell A terminal, characterized in that configured to receive data for the second control plane.
The method of claim 7, wherein the control information,
The terminal is configured to receive only the user plane from the small cell, and the terminal is configured to receive the control plane for the macro cell and the control plane for the small cell from the macro cell.
In the method of a terminal supporting carrier aggregation between at least one small cell and a macro cell, the macro cell performs frequency division duplex communication with the terminal, and the at least one small cell The cell performs time division duplex communication with the terminal within the coverage range of the macro cell,
performing communication with the macro cell through a control plane of the macro cell and a first user plane of the macro cell;
When the terminal is located within the coverage of a first small cell among the at least one small cell, while receiving user data through a second user plane for the first small cell, from the macro cell through the control plane receiving control data;
Instruct, from the macro cell, that the user data is transmitted through the first user plane of the macro cell while the terminal is outside the at least one small cell included within the coverage range of the macro cell receiving control information; and
receiving, based on the control information, data for the user plane through the first user plane of the macro cell while the terminal is outside the coverage of the first small cell; including,
When the terminal is located within the coverage of the first small cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated How to.
The method of claim 10, wherein the control information,
When the terminal moves from the first small cell to a second small cell among the at least one small cell, the method characterized in that the terminal is configured to receive data for the control plane from the macro cell.
The method of claim 10, wherein the control information,
The terminal is configured to receive only the data for the user plane from the at least one small cell, and the terminal is configured to receive the data for the first control plane related to the macro cell from the macro cell and the data related to the at least one small cell and configuring to receive data for the second control plane.
In a method of a macro cell that supports carrier aggregation for a terminal with at least one small cell in a wireless communication system, the macro cell performs frequency division duplex communication with the terminal and the at least one small cell performs time division duplex communication with the terminal within the coverage range of the macro cell, and the macro cell includes a control plane and a first user plane. Perform communication with the terminal through (user plane),
transmitting control data to the terminal through the control plane while user data is transmitted to the terminal through a second user plane for the at least one small cell existing within the coverage range of the macro cell;
Receiving a measurement report (measurement report) related to the at least one small cell from the terminal;
based on the measurement report, confirming that the terminal exists outside the at least one small cell included within the coverage range of the macro cell;
determining whether to transmit data for the user plane in the macro cell when the terminal is outside the at least one small cell included within the coverage range of the macro cell;
Control indicating that the user data is transmitted to the terminal through the first user plane of the macro cell while the terminal is outside the at least one small cell included within the coverage range of the macro cell generating information; and
transmitting the control information to the terminal; includes,
When the terminal is located within the coverage of the at least one small cell included within the coverage range of the macro cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated How to.
14. The method of claim 13,
based on the measurement report, confirming that the terminal moves from a first small cell to a second small cell among the at least one small cell;
transmitting data for the user plane from the second small cell when the second small cell is in an active state in the terminal; and
transmitting data for the user plane in the macro cell when the second small cell is in an inactive state in the terminal; Method, characterized in that it further comprises.
15. The method of claim 14,
When it is determined to transmit user data through the first user plane in the macro cell, between the first small cell deactivation time for cell change and the second small cell activation time, the user data is transmitted to the terminal step; Method, characterized in that it further comprises.
14. The method of claim 13,
When the throughput of the user data of the at least one small cell for the terminal is less than or equal to a preset threshold, the method characterized in that the user data is transmitted through the first user plane of the macro cell.
In the apparatus of a macro cell that supports carrier aggregation for a terminal between at least one small cell and at least one small cell in a wireless communication system, the macro cell performs frequency division duplex communication with the terminal. and the at least one small cell performs time division duplex communication with the terminal within the coverage range of the macro cell,
a transceiver for performing communication with the terminal through a control plane and a first user plane; and
While user data is transmitted to the terminal through a second user plane for the at least one small cell existing within the coverage range of the macro cell, control data is transmitted to the terminal through the control plane, and from the terminal Controls the transceiver to receive a measurement report related to the at least one small cell, and based on the measurement report, the terminal includes the at least one small cell within the coverage range of the macro cell. It is confirmed that it exists outside, and when the terminal exists outside the at least one small cell included within the coverage range of the macro cell, it is determined whether to transmit data for the user plane in the macro cell. and indicating that the user data is transmitted to the terminal through the first user plane of the macro cell while the terminal is outside the at least one small cell included within the coverage range of the macro cell a control unit for generating control information and controlling the transceiver to transmit the control information to the terminal; including,
When the terminal is located within the coverage of the at least one small cell included within the coverage range of the macro cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated device to do.
The method of claim 17, wherein the control unit,
Based on the measurement report, it is confirmed that the terminal moves from a first small cell to a second small cell among the at least one small cell,
If the second small cell is in an active state in the terminal, control to transmit data for the user plane in the second small cell,
When the second small cell is in an inactive state in the terminal, the device characterized in that it controls the transceiver to transmit data for the user plane in the macro cell.
The method of claim 18, wherein the control unit,
If it is determined to transmit user data through the first user plane in the macro cell, transmit the user data to the terminal between the first small cell deactivation time for cell change and the second small cell activation time Device characterized in that for controlling the transceiver.
The method of claim 17, wherein the control unit,
When the data throughput for the user plane of the at least one small cell for the terminal is less than or equal to a preset threshold, controlling the transceiver to transmit the user data through the first user plane of the macro cell device to do.
In the method of a terminal supporting carrier aggregation between at least one small cell and a macro cell in a wireless communication system, the macro cell performs frequency division duplex communication with the terminal, and the at least One small cell performs time division duplex communication with the terminal within the coverage range of the macro cell, and the macro cell provides a control plane and a first user plane. to communicate with the terminal through
receiving control data from the macro cell through the control plane while receiving user data through a second user plane for the at least one small cell that is within the coverage range of the macro cell;
transmitting, to the macro cell, a measurement report related to the at least one small cell; and
Based on the measurement report, while the terminal is outside the at least one small cell included within the coverage range of the macro cell, receiving the user data from the macro cell through the first user plane step; including,
When the terminal is located within the coverage of the at least one small cell included within the coverage range of the macro cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated How to.
22. The method of claim 21,
When the terminal moves from a first small cell to a second small cell among the at least one small cell, it receives the user data from the macro cell through the first user plane,
The user data is received from the macro cell between the inactivation time of the first small cell and the activation time of the second small cell for cell change.
22. The method of claim 21,
When the throughput of the user data of the at least one small cell for the terminal is less than or equal to a preset threshold, the method characterized in that the receiving of the user data through the first user plane of the macro cell.
In a terminal supporting carrier aggregation between at least one small cell and a macro cell in a wireless communication system, the macro cell performs frequency division duplex communication with the terminal, and the at least one The small cell performs time division duplex communication with the terminal within the coverage range of the macro cell, and the macro cell performs the communication through a control plane and a first user plane. communicate with the terminal,
a transceiver configured to communicate with at least one network node; and
Receive control data from the macro cell through the control plane while receiving user data through a second user plane for the at least one small cell that is within the coverage range of the macro cell, to the macro cell, Transmits a measurement report related to at least one small cell, and based on the measurement report, while the terminal is outside the at least one small cell included within the coverage range of the macro cell, a control unit controlling the transceiver to receive the user data from the macro cell through the first user plane; including,
When the terminal is located within the coverage of the at least one small cell included within the coverage range of the macro cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated terminal that does.
The method of claim 24, wherein the control unit,
When the terminal moves from a first small cell to a second small cell among the at least one small cell, control to receive the user data from the macro cell through the first user plane,
The user data is, between the inactivation time of the first small cell and the activation time of the second small cell for cell change, the terminal, characterized in that received from the macro cell.
The method of claim 24, wherein the control unit,
When the throughput of the user data of the at least one small cell for the terminal is less than or equal to a preset threshold value, characterized in that the transceiver is controlled to receive the user data through the first user plane of the macro cell terminal.
In the apparatus of a macro cell supporting carrier aggregation for a terminal between at least one small cell, the macro cell performs frequency division duplex communication with the terminal, and the at least One small cell performs time division duplex communication with the terminal within the coverage range of the macro cell, and the macro cell provides a control plane and a first user plane. to communicate with the terminal through
a transceiver configured to communicate with at least one network node; and
When the terminal is located within the coverage of a first small cell among the at least one small cell, while user data is transmitted to the terminal through a second user plane for the first small cell, the control plane to the terminal controls the transceiver to transmit control data through the control unit, confirms that the terminal moves out of the coverage of the first small cell, and whether a second small cell among the first small cell and the at least one small cell is activated Based on the state information on whether the terminal transmits the user data through the first user plane of the macro cell while it is outside the at least one small cell included within the coverage range of the macro cell a control unit for determining whether or not; including,
When the terminal is located within the coverage of the first small cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated device to do.
In the method of a macro cell supporting carrier aggregation for a terminal between at least one small cell, the macro cell performs frequency division duplex communication with the terminal, and the at least One small cell performs time division duplex communication with the terminal within the coverage range of the macro cell, and the macro cell provides a control plane and a first user plane. to communicate with the terminal through
When the terminal is located within the coverage of a first small cell among the at least one small cell, while user data is transmitted to the terminal through a second user plane for the first small cell, the control plane to the terminal transmitting control data via;
confirming that the terminal moves out of the coverage of the first small cell; and
Based on the state information on whether a second small cell among the first small cell and the at least one small cell is activated, the terminal is located outside the at least one small cell included in the coverage range of the macro cell. determining whether to transmit the user data over the first user plane of a macro cell while present; including,
When the terminal is located within the coverage of the first small cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated How to.
In a terminal supporting carrier aggregation between at least one small cell and a macro cell, the macro cell performs frequency division duplex communication with the terminal, and the at least one small cell includes Within the coverage range of the macro cell, time division duplex communication with the terminal is performed, and the macro cell communicates with the terminal through a control plane and a first user plane. do,
a transceiver configured to communicate with at least one network node; and
When the terminal is located within the coverage of a first small cell among the at least one small cell, while receiving user data through a second user plane for the first small cell, through the control plane of the macro cell Receive control data, and receive data for the user plane from the macro cell or the at least one small cell while the terminal is outside the at least one small cell included within the coverage range of the macro cell and a control unit for controlling the transceiver so as to
A cell transmitting the user plane data among the macro cell or the at least one cell is determined based on status information on whether a second small cell among the first small cell and the at least one small cell is activated becomes,
When the terminal is located within the coverage of the first small cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated A terminal, characterized in that.
In the method of a terminal supporting carrier aggregation between at least one small cell and a macro cell, the macro cell performs frequency division duplex communication with the terminal, and the at least one small cell The cell performs time division duplex communication with the terminal within the coverage range of the macro cell, and the macro cell performs the terminal through a control plane and a first user plane. communicate with,
When the terminal is located within the coverage of a first small cell among the at least one small cell, while receiving user data through a second user plane for the first small cell, through the control plane of the macro cell receiving control data; and
Receiving the data for the user plane from the macro cell or the at least one small cell while the terminal is outside the at least one small cell included within the coverage range of the macro cell,
A cell transmitting the user plane data among the macro cell or the at least one cell is determined based on status information on whether a second small cell among the first small cell and the at least one small cell is activated becomes,
When the terminal is located within the coverage of the first small cell and the user data is transmitted to the terminal through the second user plane, the first user plane is deactivated,
In response to the terminal being outside the at least one small cell included in the coverage of the macro cell, the first user plane of the macro cell performing FDD communication with the terminal is activated A method characterized in that

Images