WO2012086945A2 - Dispositif et procédé pour transmettre des données de motif de trame dans un système de communication sans fil - Google Patents

Dispositif et procédé pour transmettre des données de motif de trame dans un système de communication sans fil Download PDF

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WO2012086945A2
WO2012086945A2 PCT/KR2011/009382 KR2011009382W WO2012086945A2 WO 2012086945 A2 WO2012086945 A2 WO 2012086945A2 KR 2011009382 W KR2011009382 W KR 2011009382W WO 2012086945 A2 WO2012086945 A2 WO 2012086945A2
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information
base station
cell
frame pattern
terminal
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PCT/KR2011/009382
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English (en)
Korean (ko)
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WO2012086945A3 (fr
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권기범
안재현
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주식회사 팬택
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/54—Allocation or scheduling criteria for wireless resources based on quality criteria
    • H04W72/542—Allocation or scheduling criteria for wireless resources based on quality criteria using measured or perceived quality
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/24—Cell structures
    • H04W16/32—Hierarchical cell structures
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/10—Scheduling measurement reports ; Arrangements for measurement reports
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/04—Large scale networks; Deep hierarchical networks
    • H04W84/042—Public Land Mobile systems, e.g. cellular systems
    • H04W84/045—Public Land Mobile systems, e.g. cellular systems using private Base Stations, e.g. femto Base Stations, home Node B

Definitions

  • the present invention relates to wireless communication, and more particularly, to an apparatus and method for transmitting frame pattern information in a wireless communication system.
  • 3GPP LTE long term evolution
  • UMTS Universal Mobile Telecommunications System
  • 3GPP LTE uses orthogonal frequency division multiple access (OFDMA) in downlink and single carrier-frequency division multiple access (SC-FDMA) in uplink.
  • OFDMA orthogonal frequency division multiple access
  • SC-FDMA single carrier-frequency division multiple access
  • MIMO multiple input multiple output
  • LTE-A 3GPP LTE-Advanced
  • heterogeneous network As wireless communication technology develops, a heterogeneous network (hereinafter referred to as a heterogeneous network) environment is emerging.
  • the heterogeneous network environment includes a macro cell, a femto cell, a pico cell, and the like.
  • the femto cell and pico cell are systems that cover an area smaller than the radius of the existing mobile communication service as compared to the macro cell.
  • a user terminal present in any one of a macrocell, a femtocell, and a picocell may cause inter-cell interference in which signal interference is caused by a signal generated from another cell.
  • An object of the present invention is to provide an apparatus and method for transmitting frame pattern information in consideration of inter-cell interference.
  • Another technical problem of the present invention is to provide an apparatus and method for transmitting ABS (Almost Blank Subframe) pattern information.
  • Another technical problem of the present invention is to provide an apparatus and method for transmitting frame pattern information using an Automatic Neighbor Relation (ANR) procedure.
  • ANR Automatic Neighbor Relation
  • a terminal for transmitting frame pattern information is provided in a heterogeneous network system.
  • the terminal sends an RRC connection reconfiguration message for requesting frame pattern information indicating a pattern in which an absolute blank subframe (ABS) is formed for the first base station for interference coordination between the first base station and the second base station.
  • a measurement report message including an information receiver for receiving from the second base station and receiving the frame pattern information from the first base station according to the request, and physical cell identifier (PCI) information for identifying the first base station; And generating a report information generating unit and a report information transmitting unit transmitting the measurement report message, the RRC connection reconfiguration complete message and the frame pattern information to the second base station.
  • PCI physical cell identifier
  • a method for transmitting frame pattern information by a terminal in a heterogeneous network system includes measuring the strength of a signal transmitted from a femto cell, transmitting a measurement report message including physical cell ID information identifying the femto cell to a macro cell, the femto Receiving a request message from the macro cell requesting frame pattern information indicating a pattern in which an ABS of the femto cell is formed for coordination of interference between a cell and the macro cell, in response to the request message, the frame pattern Receiving information from the femto cell, and transmitting the frame pattern information to the macro cell.
  • a base station for receiving frame pattern information in a heterogeneous network system.
  • the base station determines if a femto cell does not have physical cell ID information in a neighbor relation table.
  • the frame pattern indicates a pattern in which an ABS is formed in the femto cell.
  • an information transmitter for transmitting request information for requesting information to the terminal, and a report information receiver for receiving the frame pattern information from the terminal.
  • a method of receiving frame pattern information by a base station in a heterogeneous network system In the measurement report procedure, when physical cell ID information for identifying a femto cell does not exist in a neighbor relation table, request information for requesting frame pattern information indicating a pattern in which an ABS for the femto cell is formed is transmitted to a terminal. Transmitting, and receiving the frame pattern information from the terminal.
  • inter-cell interference attenuation is required. Interference between the macro cell and the femto cell can be attenuated by transferring the frame pattern information of the femto cell to the macro cell through the terminal. In addition, since the frame pattern information does not pass through the base station and the core network, the implementation may be easy and the complexity may be lowered.
  • FIG. 1 is a block diagram illustrating a wireless communication system to which the present invention is applied.
  • FIG. 2 is a block diagram showing a functional split between an E-UTRAN and an EPC to which the present invention is applied.
  • FIG. 3 is a block diagram showing a radio protocol architecture for a user plane to which the present invention is applied.
  • FIG. 4 is a block diagram showing a radio protocol structure for a control plane to which the present invention is applied.
  • FIG. 5 is a diagram schematically illustrating a concept of a heterogeneous network including a macro cell, a femto cell, and a pico cell to which the present invention is applied.
  • FIG. 6 is a conceptual diagram schematically illustrating a configuration of a femtocell to which the present invention is applied.
  • FIG. 7 is a schematic illustration of a network structure for operating an HNB using an HNB gateway (GW) to which the present invention is applied.
  • GW HNB gateway
  • FIG. 8 is a diagram schematically illustrating that a user terminal is affected by interference between a macro cell, a femto cell, and a pico cell in downlink to which the present invention is applied.
  • FIG. 9 is a diagram schematically illustrating a case where a femtocell to which the present invention is applied receives interference from a macro cell.
  • FIG. 10 is a diagram illustrating a frame pattern for inter-cell interference coordination in a heterogeneous network system according to an embodiment of the present invention.
  • FIG. 11 is a flowchart illustrating a method of transmitting a frame pattern according to an embodiment of the present invention.
  • FIG. 12 is a flowchart illustrating a method of transmitting frame pattern information of a terminal according to an embodiment of the present invention.
  • FIG. 13 is a flowchart illustrating a method of receiving frame pattern information of a base station according to an embodiment of the present invention.
  • FIG. 14 is a conceptual diagram illustrating a transmission procedure of frame pattern information according to an embodiment of the present invention.
  • 15 is a block diagram illustrating a heterogeneous network system according to an embodiment of the present invention.
  • the present invention relates to the transmission of frame pattern information in a communication system in which various types of cells, such as a macro cell, a pico cell, a femto cell, and the like exist.
  • the present specification describes a communication network, the operation performed in the communication network is performed in the process of transmitting the data and controlling the network in the system (for example, the base station) that manages the communication network, or the terminal coupled to the network Work can be done in the system (for example, the base station) that manages the communication network, or the terminal coupled to the network Work can be done in the system (for example, the base station) that manages the communication network, or the terminal coupled to the network Work can be done in the system (for example, the base station) that manages the communication network, or the terminal coupled to the network Work can be done in the system (for example, the base station) that manages the communication network, or the terminal coupled to the network Work can be done in the system (for example, the base station) that manages the communication network, or the terminal coupled to the network Work can be done in the system (for example, the base station) that manages the communication network, or the terminal coupled to the network Work can be done in the system (for example, the base station) that manages the communication network, or the terminal
  • FIG. 1 is a block diagram illustrating a wireless communication system to which the present invention is applied.
  • the E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) includes a base station 20 (BS) that provides a control plane and a user plane to a user equipment (UE) 10. do.
  • BS base station 20
  • UE user equipment
  • the terminal 10 may be fixed or mobile, and may be called by other terms such as a mobile station (MS), a user terminal (UT), a subscriber station (SS), a mobile terminal (MT), and a wireless device. .
  • MS mobile station
  • UT user terminal
  • SS subscriber station
  • MT mobile terminal
  • wireless device a wireless device
  • the base station 20 refers to a station that communicates with the terminal 10, and includes an evolved-NodeB (eNB), a base transceiver system (BTS), an access point, an femto base station, and a pico base station. It may be called other terms such as pico eNB, home eNB, relay, remote radio head (RRH).
  • eNB evolved-NodeB
  • BTS base transceiver system
  • femto base station femto base station
  • pico base station It may be called other terms such as pico eNB, home eNB, relay, remote radio head (RRH).
  • One or more cells may exist in one base station 20.
  • the cell should be interpreted in a comprehensive sense indicating a part of the area covered by the base station 11, and covers all of the various coverage areas such as a mega cell, a macro cell, a micro cell, a pico cell, a femto cell, a relay, and a hot spot. It is meant to be comprehensive.
  • An interface for transmitting user traffic or control traffic may be used between the base stations 20.
  • the base stations 20 may be connected to each other through an X2 interface.
  • the base station 20 is connected to a Mobility Management Entity (MME) through an Evolved Packet Core (EPC), more specifically, S1-MME through an S1 interface, and a Serving GateWay (S-GW) through S1-U.
  • MME Mobility Management Entity
  • EPC Evolved Packet Core
  • S1-MME Serving GateWay
  • S-GW Serving GateWay
  • the S1 interface supports a many-to-many-relation between the base station 20 and the MME / SAE gateway 30.
  • the base stations 20 are connected by the X2 interface.
  • downlink means communication from the base station 20 to the terminal 10
  • uplink means communication from the terminal 10 to the base station 20.
  • the transmitter may be part of the base station 20 and the receiver may be part of the terminal 10.
  • the transmitter in uplink, may be part of the terminal 10 and the receiver may be part of the base station 20.
  • FIG. 2 is a block diagram showing a functional split between an E-UTRAN and an EPC to which the present invention is applied.
  • the hatched box represents the radio protocol layer and the white box represents the functional entity of the control plane. Describe the function of each functional entity.
  • the base station performs the following functions.
  • Radio resource management such as radio bearer control, radio admission control, connection mobility control, and dynamic resource allocation to a terminal ; RRM) function.
  • IP Internet Protocol
  • IP Internet Protocol
  • the MME performs the following functions.
  • Non-Access Stratum NAS
  • NAS signaling (2) NAS signaling security.
  • idle mode UE Reachability (3) idle mode UE Reachability, (4) tracking area list management.
  • Roaming Functions (6) Authentication.
  • S-GW performs the following functions.
  • P-GW P-Gateway
  • Terminal IP Internet Protocol
  • packet filtering
  • 3 is a block diagram showing a radio protocol architecture for a user plane to which the present invention is applied.
  • 4 is a block diagram showing a radio protocol structure for a control plane to which the present invention is applied.
  • the data plane is a protocol stack for user data transmission
  • the control plane is a protocol stack for control signal transmission.
  • a physical layer provides an information transfer service to a higher layer by using a physical channel.
  • the physical layer is connected to a medium access control (MAC) layer, which is a higher layer, through a transport channel.
  • MAC medium access control
  • Transport channels are classified according to how and with what characteristics data is transmitted over the air interface.
  • Data and control information move between different physical layers, that is, between physical layers of a transmitter and a receiver, through a physical channel.
  • PDCCH Physical Downlink Control CHannel
  • PCH Paging CHannel
  • DL-SCH DownLink Shared CHannel
  • HARQ Hybrid Automatic Repeat reQuest
  • the PDCCH may carry an uplink scheduling grant informing the UE of resource allocation of uplink transmission.
  • PCFICH Physical Control Format Indicator CHannel
  • PHICH Physical Hybrid ARQ Indicator CHannel
  • PUCCH Physical Uplink Control CHannel
  • uplink control information such as HARQ ACK / NAK, scheduling request, and CQI for downlink transmission.
  • PUSCH Physical Uplink Shared CHannel
  • UL-SCH UpLink Shared CHannel
  • Functions of the MAC layer include mapping between logical channels and transport channels and multiplexing / demultiplexing into transport blocks provided as physical channels on transport channels of MAC service data units (SDUs) belonging to the logical channels.
  • SDUs MAC service data units
  • the MAC layer provides a service to a Radio Link Control (RLC) layer through a logical channel.
  • the logical channel may be divided into a control channel for transmitting control region information and a traffic channel for delivering user region information.
  • Functions of the RLC layer include concatenation, segmentation, and reassembly of RLC SDUs.
  • the RLC layer uses a transparent mode (TM), an unacknowledged mode (UM), and an acknowledged mode. , Three modes of operation (AM).
  • AM RLC provides error correction through Automatic Repeat reQuest (ARQ).
  • Functions of the Packet Data Convergence Protocol (PDCP) layer in the user plane include delivery of user data, header compression, and ciphering.
  • Functions of the PDCP layer in the user plane include the transfer of control plane data and encryption / integrity protection.
  • PDCP Packet Data Convergence Protocol
  • the RRC (Radio Resource Control) layer is defined only in the control plane.
  • the RRC layer is responsible for the control of logical channels, transport channels and physical channels in connection with the configuration, re-configuration and release of radio bearers.
  • the radio bearer refers to a logical path provided by the first layer (PHY layer) and the second layer (MAC layer, RLC layer, PDCP layer) for data transmission between the terminal and the network.
  • the establishment of the RB means a process of defining characteristics of a radio protocol layer and a channel to provide a specific service, and setting each specific parameter and operation method.
  • the radio bearer RB may be divided into two types, a signaling RB (SRB) and a data RB (DRB).
  • SRB is used as a path for transmitting RRC messages in the control plane
  • DRB is used as a path for transmitting user data in the user plane.
  • the non-access stratum (NAS) layer located above the RRC layer performs functions such as session management and mobility management.
  • a scheduler is one way to deal with this quality link change.
  • the scheduler for the downlink is generally a round-robin scheduler in which terminals alternately use shared resources without considering the channel state, and the terminal with the absolute best downlink channel state is scheduled.
  • -C / I scheduler also known as maximum rate scheduler
  • PF Proportional-Fair
  • a greedy filling scheduler commonly used in non-orthogonal multiple access schemes.
  • uplink scheduling may be different from downlink scheduling, but the above-described scheduling principles for downlink may also be applied to uplink.
  • heterogeneous network in which heterogeneous cells exist in the same space, coordination between different cells constituting the heterogeneous network needs to be considered along with scheduling of the terminal.
  • a heterogeneous network will be described.
  • pico cells can generally be used in communication shadow areas that are not covered by macro cells alone, or in areas with high data service requirements, so-called hot zones.
  • Femtocells can generally be used in indoor offices or at home.
  • the wireless relay can supplement the coverage of the macro cell.
  • FIG. 5 is a diagram schematically illustrating a concept of a heterogeneous network including a macro cell, a femto cell, and a pico cell to which the present invention is applied.
  • FIG. 5 illustrates a heterogeneous network composed of a macro cell, a femto cell, and a pico cell for convenience of description, the heterogeneous network may include a relay or another type of cell.
  • a macro cell 510, a femto cell 520, and a pico cell 530 are operated together.
  • the macro cell 510, the femto cell 520, and the pico cell 530 each have their own cell coverage.
  • a femto cell is a low power wireless access point, which is a small base station for mobile communication used indoors such as a home or an office.
  • a femto cell can connect to a mobile communication core network using a DSL or cable broadband in a home or office.
  • FIG. 6 is a conceptual diagram schematically illustrating a configuration of a femtocell to which the present invention is applied.
  • a femto base station 620 in a home 610 or an office is connected to a mobile communication network 640 through a wired network 630 such as an internet network.
  • the terminal 650 in the femto cell may access the mobile communication network 640 or the internet network through the femto base station 620.
  • the femto cells may be supported with a self-organization (Self-Organization) function.
  • Self-organization functions are classified into a self-configuration function, a self-optimization function, and a self-monitoring function.
  • Self-configuration is a feature that allows a wireless base station to be installed on its own based on an initial installation profile without going through a cell planning step.
  • Self-Optimization is a function that identifies neighboring base stations, obtains information, optimizes the neighboring base station list, and optimizes coverage and communication capacity according to subscriber and traffic changes.
  • Self-Monitoring is a function to control service performance not to be degraded through collected information.
  • Plug and Play functionality is required. This includes IP address strokes, RF / Radio parameters and / or network parameter settings, software installation, base station recognition and / or authentication, and security procedures such as authentication / authorization can also be performed without operator assistance.
  • the femtocell may distinguish registered users from unregistered users and allow access only to registered users.
  • Cells that allow access only to registered users are called Closed Subscriber Groups (“CSGs”), and access to general users is also called Open Subscriber Groups (“OSGs”). Is called). It is also possible to mix these two methods.
  • the base station providing the femtocell service is called a femto BS, a home NodeB (HNB), or an advanced home eNodeB (HeNB).
  • HNB home NodeB
  • HeNB advanced home eNodeB
  • the femto base station, the HNB, and the HeNB are collectively referred to as an HNB.
  • the HNB basically aims to provide specialized services only to members belonging to the CSG. However, the service may be provided to other users besides the CSG according to the operation mode setting of the HNB.
  • FIG. 7 is a schematic illustration of a network structure for operating an HNB using an HNB gateway (GW) to which the present invention is applied.
  • GW HNB gateway
  • the HNBs 31 are connected to the EPC (not shown in the figure) or directly to the EPC via the HNB GW 32.
  • the HNB GW 32 appears to the MME 30 as a normal base station.
  • the HNB GW 32 also looks like the MME 30 to the HNB 31. Therefore, the HNB 31 and the HNB GW 32 are connected by the S1 interface, and the HNB GW 30 and the EPC are also connected by the S1 interface.
  • the HNB 31 and the EPC are directly connected, they are connected to the S1 interface.
  • the function of the HNB 31 is mostly the same as that of a general base station.
  • the HNB has a lower wireless transmission power than the BS owned by the mobile network operator. Therefore, the coverage provided by the HNB is generally smaller than the service area provided by the BS. Due to this characteristic, a cell provided by an HNB may be classified as a femto cell in comparison with a macro cell provided by a BS from a service area perspective.
  • a cell provided by the HNB is referred to as a CSG cell.
  • Each CSG has its own unique identifier, which is called a CSG identity (CSG identity).
  • the terminal may have a list of CSGs belonging to the member, and the CSG list may be changed by a request of the terminal or a command of the network.
  • one HNB can support one CSG.
  • the terminal has a list of CSG registered as a member, which is called a CSG white list.
  • the HNB delivers the CSG ID of the CSG supported by the HNB through the system information so that only the member terminals of the corresponding CSG are connected.
  • the UE finds a CSG cell, it can check which CSG the CSG cell supports by reading the CSG ID included in the system information.
  • the terminal reading the CSG ID is regarded as a cell that can access the cell only when the UE is a member of the CSG cell, that is, when the CSG corresponding to the CSG ID is included in its CSG whitelist.
  • HNB does not always need to allow access to the CSG terminal.
  • Which UE is allowed to access depends on the configuration setting of the HNB, where the configuration setting refers to the setting of the operation mode of the HNB.
  • the operation mode of the HNB is classified into three types according to which UE provides a service.
  • Closed access mode A mode in which a service is provided only to a specific CSG member.
  • the HNB provides a CSG cell.
  • Open access mode A mode in which a service is provided without restriction of a specific CSG member like a general BS.
  • the HNB provides a generic cell that is not a CSG cell.
  • Hybrid access mode A mode in which a CSG service can be provided to a specific CSG member and a service is provided to a non-CSG member like a normal cell.
  • CSG member UEs are recognized as CSG cells, and non-CSG member UEs are recognized as normal cells. Such a cell is called a hybrid cell.
  • the user can access a desired cell among the macro cell and the femto cell to use the data service.
  • the end user using the macro cell will not be able to use the femto cell even if the macro cell is interfering with the femto cell transmitting a strong signal.
  • macro base stations are connected to each other via an X2 interface (interface).
  • the X2 interface maintains the operation of seamless and lossless handover between base stations and supports management of radio resources. Therefore, the X2 interface plays a large role in inter-cell interference coordination (ICIC) between macro base stations.
  • IIC inter-cell interference coordination
  • FIG. 8 is a diagram schematically illustrating that a user terminal is affected by interference between a macro cell, a femto cell, and a pico cell in downlink to which the present invention is applied.
  • the user terminal 850 may access the femto cell 830.
  • the user terminal 860 cannot connect to the femto cell 830 with strong signal strength.
  • the user terminal 860 may receive an interference signal from the femto cell 830.
  • the user terminal 840 may access the pico cell 820. However, at this time, the user terminal 840 may be affected by the interference by the macro cell 810.
  • FIG. 9 is a diagram schematically illustrating a case where a femtocell to which the present invention is applied receives interference from a macro cell.
  • the macro base station 910 may dynamically signal with the femto base station 930 through an X2 interface.
  • the macro base station 920 may dynamically signal with the femto base station 940 through an X2 interface.
  • the user terminal connected to the femto base station 930 may receive unwanted interference from the macro base station 920.
  • a macro cell that is more affected by the interference or needs to be further protected from the interference is a macro cell.
  • an aggressor cell that affects or is less affected by the Victim cell by the interference is a femto cell.
  • the interference of the weak signal of the macro cell is greater than the signal of the strong strength output from the nearby femto base station, because there are much more users of the macro cell than the user of the femto cell. In other words, it is very likely that there are terminals that cannot move to the femto cell among the terminals in the macro cell that enter the area where the signal of the femto cell is strongly received.
  • Inter-Cell Interfernce Coordination is a method of reducing inter-cell interference.
  • inter-cell interference coordination is a method for supporting reliable communication to a user when a user connected to a Victim cell is near an aggregator cell.
  • a scheduler may be imposed on the use of certain time and / or frequency resources. It may also impose a constraint on the scheduler how much power to use for a particular time and / or frequency resource.
  • FIG. 10 is a diagram illustrating a frame pattern for inter-cell interference coordination in a heterogeneous network system according to an embodiment of the present invention.
  • a frame pattern is configured such that interference does not occur between different types of cells (macro cell and femto cell).
  • the macro cell hardly transmits a signal, so the transmission power is very low. Therefore, in this case, since there is almost no signal transmitted in the subframe, such a subframe is called ABS (almost blank subframe: ABS).
  • ABS is used by the femto cell and used to rule out interference with the macro cell.
  • ABS is formed in a specific pattern in the radio frame for coordination of interference, which is called a frame pattern.
  • the frame pattern may be called an ABS pattern.
  • the interference is adjusted by variably configuring the ABS in any periodic section composed of a plurality of subframes.
  • ABS considered in the present invention will be described based on the ABS in the form of emptying information on the area allocated for a specific terminal of the control channel information and data channel information. Accordingly, signals such as pilot signals, synchronization signals, ACK / NACK transmission signals, and the like other than the above information are also transmitted in the ABS.
  • the frame pattern of the macro cell and the femto cell is preferably static or semi-static as shown in FIG. 10.
  • the description of the present invention will be described by specifying only the interference between the macro cell and the femto cell, but this is only an example and may be applied to the interference between the macro cell and the pico cell.
  • the frame pattern may be set differently for each femto cell. Since femto cells can be installed anywhere and anytime, it is difficult for a macro cell to know all the frame patterns of all femto cells. Furthermore, it has not been determined yet how the macro cell acquires the frame pattern information of the femto cell. However, acquiring the frame pattern information of all femto cells through the S1 interface and the core network has a problem of increasing time delay and system complexity. Therefore, there is a need for an apparatus and method for a macro cell to efficiently obtain a frame pattern for a femto cell.
  • the present invention provides an automatic neighbor relation (ANR) procedure aimed at minimizing or eliminating manual operations on neighbor BS information when the macro BS optimizes neighbor BS information.
  • ANR automatic neighbor relation
  • the present invention provides an apparatus and method for setting a newly installed femto base station as an adjacent base station and transmitting frame pattern information about the femto base station to the macro base station.
  • FIG. 11 is a flowchart illustrating a method of transmitting a frame pattern according to an embodiment of the present invention.
  • the terminal, the macro base station and the femto base station all support the ANR procedure.
  • the femto base station when a femto BS is connected to a network, the femto base station periodically transmits system information about the femto cell to the UE through a broadcast channel (BCCH) on the femto cell. (S1100).
  • BCCH broadcast channel
  • the terminal transmits a measurement report message for reporting measurement results for all neighboring cells for which physical cell ID (hereinafter, referred to as "PCI") information is confirmed (S1105).
  • the measurement report message includes a neighbor cell list and PCI information.
  • the neighbor cell includes the femto cell, and the strength of the received signal of the femto cell is the strongest.
  • the terminal receives a measurement report request from the macro base station (Macro BS), and performs the measurement report to the base station in response thereto.
  • the macro base station determines that the neighbor cell having a signal strength equal to or greater than a predetermined threshold value in the neighbor cell list in the measurement report message includes a neighbor relation table including information on a plurality of neighbor cells. NRT ”) (S1110).
  • the macro base station transmits a first RRC connection reconfiguration message including ECGI request information for requesting various pieces of information necessary for identifying the unknown cell to the terminal (S1115).
  • the ECGI request information is information for setting a periodic measurement report purpose.
  • the macro base station may select and set only one of the “reported ECGI of the indicated neighboring cell” and the “reported neighboring cell with the strongest signal strength”.
  • the serving base station to which the terminal belongs is configured to report a signal having the greatest signal strength among the received signals received from all base stations currently measured by the terminal in order of measured cells. Only one of report strongest cells ”or“ report ECGI ”configured to report ECGI information, which is unique information about the neighboring cell, may be set for acquiring and establishing information on the neighboring cell which is not recognized by the serving base station.
  • the terminal transmits the first RRC connection reconfiguration complete message to the macro base station (S1120). Thereafter, the terminal receives system information transmitted from the unknown cell (here femto cell) that causes the ECGI request information in a broadcast listening interval (BLI) (S1125).
  • the broadcast listening period is set by an idle period setting parameter or an autonomous measurement gap included in measurement report request information received from the macro base station.
  • the terminal may receive the measurement report request information when the RRC connection establishment (establishment) or after the RRC connection reconfiguration (reconfiguration).
  • the system information includes a first system information block (SIB1).
  • the UE acquires an ECGI value through cell identity and public land mobile network (PLMN) identity information included in the SIB1 (S1130).
  • PLMN public land mobile network
  • the terminal recognizes that the unknown cell is a femto cell and acquires frame pattern information of the femto cell included in the SIB1 (S1135).
  • the frame pattern information may be included in other SIBs other than SIB1.
  • the frame pattern information may be transmitted through another channel, for example, a UE dedicated channel, a physical control channel, or a MAC message or an RRC message.
  • the frame pattern information may be transmitted in the form of a bitmap of 20 bits or 40 bits, or may be transmitted in an index form through a table reference.
  • the UE may recognize the unknown cell as a femto cell.
  • the terminal may recognize that the unknown cell is a femto cell.
  • the terminal transmits the ECGI value and the frame pattern information to the macro base station through the defined periodic measurement report procedure (S1140).
  • the ECGI value and the frame pattern information may be included in the RRC message, the MAC message or the physical layer control information and transmitted.
  • the frame pattern includes an ABS pattern.
  • the macro base station does not directly receive the SIB1 from the femto cell, the macro base station may receive the frame pattern information from the terminal by a simple procedure through an ANR. This does not require a complicated procedure of transmitting the frame pattern information through the core network, and can be very easy to implement.
  • the macro base station adds the femto cell to the NRT.
  • the RRC configuration of UEs determined to be affected by interference from the femto cell is changed (S1145).
  • the change of the RRC configuration may include changing a setting for reference signal received power (RSRP) / reference signal received quality (RSRQ) measurement for a serving cell, and for RSRP / RSRQ measurement for an adjacent cell. Changes to settings and changes to settings for time / frequency resources where CQI measurements are possible. Configuration of RSRP / RSRQ measurement for the neighbor cell may be configured for each neighbor cell, may be the same for neighbor cells grouped based on PCI, or may be the same for all neighbor cells.
  • RSRP reference signal received power
  • RSRQ reference signal received quality
  • the macro base station transmits a second RRC connection reconfiguration message including the changed configuration to the terminal (S1150). After completing the second RRC connection reconfiguration, the terminal transmits a second RRC connection reconfiguration complete message to the macro base station (S1155).
  • FIG. 11 illustrates a case in which the UE recognizes that an unknown cell is a femto cell or a hybrid cell from PCI information or CSG identification information. Therefore, even if the macro base station does not separately request frame pattern information about the femto cell, the terminal may voluntarily acquire frame pattern information of the femto cell and inform the macro base station. On the other hand, there may be a case where the terminal needs to obtain frame pattern information at the request of the macro base station. This is illustrated in FIG. 12.
  • FIG. 12 is a flowchart illustrating a method of transmitting frame pattern information of a terminal according to an embodiment of the present invention.
  • the terminal performs measurement reports on all neighbor cells in which PCI information is confirmed for the macro base station (S1200).
  • the measurement report may be performed at the RRC layer.
  • various procedures related to radio resource management are defined, such as system information broadcasting, RRC connection management procedures, radio bearer control procedures, security procedures, measurement procedures, and mobility management procedures (handover).
  • the measurement procedure provides the base station with various information necessary for proper network management and resource allocation considering the wireless environment.
  • RRC messages related to measurement are information related to measurement to be performed by the terminal.
  • the measurement related parameters are broadcasted through system information or delivered to the terminal through a measurement control message.
  • the terminal reports the measurement result to the macro base station when a periodic or specific event occurs by transmitting a measurement report message.
  • TTT time to trigger
  • the terminal receives a first RRC connection reconfiguration message including ECGI request information and frame pattern request information from the macro base station (S1205). Unlike in FIG. 11, the first RRC connection reconfiguration message further includes frame pattern request information.
  • the frame pattern request information is information for requesting the terminal for frame pattern information about a new neighbor cell that does not exist in the NRT.
  • the terminal transmits a first RRC connection reconfiguration complete message to the macro base station (S1210).
  • the terminal receives system information on the femtocell currently being broadcast through the broadcast channel from the femtocell in the set broadcast listening section (S1215).
  • the system information is a system information block and includes SIB1.
  • SIB1 includes at least one of cell identification information, PLMN identification information, and frame pattern information.
  • the terminal determines whether frame pattern request information exists in the first RRC connection reconfiguration message (S1220). If the frame pattern request information exists, the terminal acquires the frame pattern information in response to the frame pattern request information, and also obtains an ECGI value (S1225). If the frame pattern request information does not exist, the terminal acquires an ECGI value through the cell identification information and the PLMN identification information in response to the ECGI request information (S1230).
  • step S1220 is shown to occur after S1215, this is only an example, and S1215 may be performed after step S1220, which is merely an implementation difference.
  • the terminal transmits the obtained ECGI value and / or frame pattern information to the macro base station (S1235).
  • the ECGI value and the frame pattern information may be included in the RRC message, the MAC message or the physical layer control information and transmitted.
  • the terminal receives a second RRC connection reconfiguration message from the macro base station (S1240).
  • the terminal reconfigures the RRC connection according to the second RRC connection reconfiguration message and transmits a second RRC connection reconfiguration complete message to the macro base station (S1245).
  • the base station here includes a macro base station.
  • the base station receives measurement report messages for all neighbor cells in which PCI information is confirmed (S1300).
  • the base station checks from the PCI information whether the neighboring cell having a signal strength above a predetermined threshold value in the neighboring cell list in the measurement report message exists in the NRT (S1305).
  • the base station is configured to terminal the first RRC connection reconfiguration message including ECGI request information for requesting various pieces of information necessary for identifying the unknown cell and frame pattern request information for requesting frame pattern information about the unknown cell.
  • the base station receives a first RRC connection reconfiguration complete message from the terminal (S1315). Thereafter, the base station receives an ECGI value in response to the ECGI request information or receives frame pattern information in response to the frame pattern request information (S1320). The base station adds the unknown cell to the NRT.
  • the RRC configuration of UEs determined to be affected by interference from the unknown cell is changed in consideration of the frame pattern of the unknown cell (S1325). For example, a change in the RRC setting may include changing a setting for reference signal received power (RSRP) / reference signal received quality (RSRQ) measurement for a serving cell and a setting for RSRP / RSRQ measurement for an adjacent cell. Change of the configuration of the time and frequency resources available for CQI measurement.
  • RSRP reference signal received power
  • RSRQ reference signal received quality
  • Configuration of RSRP / RSRQ measurement for the neighbor cell may be configured for each neighbor cell, may be the same for neighbor cells grouped based on PCI, or may be the same for all neighbor cells.
  • the base station transmits a second RRC connection reconfiguration message indicating a change in the RRC configuration for the terminal to the terminal (S1330), and receives a second RRC connection reconfiguration complete message indicating that the second RRC connection reconfiguration is completed (S1335). ).
  • FIG. 14 is a conceptual diagram illustrating a transmission procedure of frame pattern information according to an embodiment of the present invention.
  • a heterogeneous network system includes a macro cell 1400, a femto cell 1405, and a terminal 1410.
  • the PID information of the macro cell 1400 is 3 and the ECGI value is 17.
  • PID (Phy-CID) information of the femto cell 1405 is 5
  • the ECGI value is 19 and the femto cell 1405 operates in a specific frame pattern.
  • the terminal 1410 includes a function or capability for recognizing that the femto cell 1405 enters the network during communication with the macro cell 1400.
  • the UE 1410 receives a measurement report request from the connected macro cell 1400 after the RRC connection is established, and continuously detects all detected PCI information as indicated in the measurement report request while in the RRC connected mode. Report to macro cell 1400.
  • the UE 1410 transmits PID (Phy-CID) information of the femto cell 1405 measured by the UE 1410 to the macro cell 1400 (S1400).
  • PID Physical Cell ID
  • the ANR function of the macro cell 1400 may determine the femto cell 1405. Based on the PCI information to identify, request to the terminal 1410 to retrieve the ECGI and frame pattern information of the femto cell 1405 (S1405). At this time, the macro cell 1400 sets PID information of the femto cell 1405, which is a request target, to 5 and transmits it. Accordingly, the UE 1410 may specify which neighboring cell the ECGI value and the frame pattern information to which the UE should transmit to the macro cell 1400 are related.
  • the terminal 1410 reads a Broadcast Control CHannel (BCCH) broadcast from the femtocell 1405 (S1410).
  • BCCH Broadcast Control CHannel
  • SIB1 including the PID information, the ECGI value, and the frame pattern information of the femto cell 1405.
  • the terminal 1410 transmits the ECGI value and / or frame pattern information of the femto cell 1405 having PID information of 5 to the macro cell 1400. If the femto cell 1405 is a CSG cell or a mixed cell, the terminal 1410 also transmits a CSG ID.
  • the macro cell 1400 adds a femto cell 1405 to the NRT. If necessary, the macro cell 1400 may set a new interface, for example, an X2 interface.
  • 15 is a block diagram illustrating a heterogeneous network system according to an embodiment of the present invention.
  • a heterogeneous network system includes a macro base station 1500, a femto base station 1540, and a terminal 1580.
  • an ANR procedure is used for transmission of frame pattern information of the femto base station 1540.
  • the macro base station 1500 includes an information transmitter 1505 and a report information receiver 1510.
  • the information transmitter 1505 receives the PCI information from the terminal 1580, and checks whether the neighbor cell having the signal strength equal to or greater than a predetermined threshold value in the neighbor cell list in the measurement report message exists in the NRT based on the PCI information. If the neighbor cell is present in the NRT, the information transmitter 1505 transmits a message including frame pattern request information and / or ECGI request information to the terminal 1580.
  • the message may be an RRC connection reconfiguration message. Alternatively, the message may be a message generated in the MAC layer.
  • the frame pattern request information is information for requesting the UE for frame pattern information on a new neighbor cell, which is not present in the NRT.
  • the information transmitter 1505 adds the new neighbor cell to the NRT and sets RSRP / RSRQ measurement for the serving cell to terminals determined to be affected by interference in consideration of the frame pattern of the neighbor cell.
  • the configuration of the RSRP / RSRQ for the measurement and the RRC configuration for the time / frequency resources capable of CQI measurement is changed, and the RRC connection reconfiguration message according to the changed RRC configuration is transmitted to the terminal 1580.
  • Configuration of RSRP / RSRQ measurement for the neighbor cell may be configured for each neighbor cell, may be the same for neighbor cells grouped based on PCI, or may be the same for all neighbor cells.
  • the report information receiver 1510 receives frame pattern information about the femto base station 1540 from the terminal 1580.
  • the frame pattern information is defined as described with reference to FIG. 10, and the report information receiver 1510 may receive an ECGI value simultaneously with the frame pattern information.
  • the frame pattern information and / or the ECGI value may be transmitted by being included in the RRC message, the MAC message or the physical layer control information.
  • the report information receiver 1510 receives a measurement report message from the terminal 1580.
  • the femto base station 1540 includes a frame pattern information generator 1545 and a broadcast channel transmitter 1550.
  • the frame pattern information generator 1545 generates frame pattern information, ECGI values, and PCI information of the femto base station 1540.
  • the broadcast channel transmitter 1550 broadcasts information that all terminals need to receive, such as system information, through BCCH.
  • the broadcast channel transmitter 1550 includes the frame pattern information generated by the frame pattern information generator 1545 in the system information, for example, SIB1, and transmits it to the terminal 1580.
  • the terminal 1580 includes an information receiver 1585, a report information generator 1590, and a report information transmitter 1595.
  • the information receiver 1585 receives an RRC connection reconfiguration message including frame pattern request information and / or ECGI request information from the macro base station 1500 and receives frame pattern information from the femto base station 1540 in a preset broadcast listening interval. do.
  • the report information generation unit 1950 performs a measurement report on all neighbor cells in which PCI information is confirmed to the macro base station 1500 and generates a measurement report message including the neighbor cell list and the PCI information.
  • the report information generation unit 1590 generates frame pattern information and / or ECGI values and PCI information.
  • the report information transmitter 1595 transmits the measurement report message, the frame pattern information, and / or the ECGI value to the macro base station 1500.
  • a method of reducing an influence of interference on downlink transmission of a macro cell by restricting a pattern of a downlink subframe of a femto cell in a heterogeneous network has been described.
  • the present invention is limited thereto. It should be noted that the technical idea of the present invention can be applied to limiting the pattern of the downlink subframe of the macro cell to reduce the influence of interference with the pico cell.
  • Control information transmitted from the upper layer described in the present invention may be transmitted in a separate physical control channel, and may be updated periodically or aperiodically at the request of a base station or a terminal or according to a predetermined rule or indication. .

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  • Engineering & Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

La présente invention se rapporte à un dispositif et à un procédé adaptés pour transmettre des données de motif de trame dans un système de communication sans fil. Le terminal décrit dans la présente invention comprend : un module de réception de données, adapté pour recevoir, en provenance d'une seconde station de base, un message de reconfiguration de connexion RRC qui demande des données de motif de trame représentant un motif ayant une sous-trame pratiquement vide (ABS, Almost Blank Subframe) pour une première station de base, en vue d'ajuster un niveau de brouillage entre la première station de base et la seconde station de base ; un module de génération de données de rapport, adapté pour générer un message de rapport de mesure contenant des données relatives à un identifiant de cellule physique (PCI), en vue d'identifier la première station de base ; et un module de transmission de données de rapport, adapté pour transmettre, à la seconde station de base, le message de rapport de mesure, un message d'accomplissement de reconfiguration de connexion RRC et les données de motif de trame. Selon la présente invention, les données de motif de trame d'une femtocellule, qui doivent servir à réduire un niveau de brouillage entre cellules, sont transmises à une macrocellule via un terminal, de telle sorte qu'un brouillage entre la macrocellule et la femtocellule puisse être réduit.
PCT/KR2011/009382 2010-12-21 2011-12-06 Dispositif et procédé pour transmettre des données de motif de trame dans un système de communication sans fil WO2012086945A2 (fr)

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KR10-2010-0131865 2010-12-21
KR1020100131865A KR20120070346A (ko) 2010-12-21 2010-12-21 무선통신 시스템에서 프레임 패턴 정보의 전송장치 및 방법

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WO2014014317A1 (fr) * 2012-07-19 2014-01-23 Samsung Electronics Co., Ltd. Procédé et système pour acheminer des informations de système à un équipement d'utilisateur dans une région de brouillage dans le même canal
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WO2014051285A1 (fr) * 2012-09-27 2014-04-03 엘지전자 주식회사 Procédé et appareil pour commander un brouillage dans un système de communication sans fil
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