WO2013176466A1

WO2013176466A1 - Method for sharing wireless resource information in multi-cell wireless communication system and apparatus for same

Info

Publication number: WO2013176466A1
Application number: PCT/KR2013/004450
Authority: WO
Inventors: 이승민; 서한별; 김학성; 김병훈
Original assignee: 엘지전자 주식회사
Priority date: 2012-05-21
Filing date: 2013-05-21
Publication date: 2013-11-28
Also published as: CN104335653A; CN104335653B; KR20150020559A; KR102108070B1

Abstract

The present invention relates to a method for sharing wireless resource information by a cell in a multi-cell wireless communication system. More particularly, the method for sharing wireless resource information by a cell according to the present invention comprises: a step of transmitting wireless resource information to a neighbor cell; and a step of receiving an acknowledgement message corresponding to the wireless resource information from the neighbor cell. The wireless resource information is information for changing the use of the wireless resource of a specific wireless resource region, and the acknowledgement message is a message indicating whether the change in use of the wireless resource is allowed in the neighbor cell.

Description

【Specification】

[Name of invention]

Method for sharing radio resource information in multi-cell wireless communication system and apparatus therefor

Technical Field

The present invention relates to a wireless communication system, and more particularly, to a method and apparatus for sharing radio resource information in a multi-cell wireless communication system.

Background Art

As an example of a wireless communication system to which the present invention can be applied, a 3GPP LTE (3rd Generation Partnership Project Long Term Evolut ion (hereinafter referred to as "LTE" 5)) communication system will be described.

1 is a diagram schematically illustrating an E—UMTS network structure as an example of a wireless communication system. E— UMTS (Evolved Universal Mobile Telecommunications System) 入 1 The system is an evolution from the existing Universal Mobile Telecom Universal Systems (UMTS), and is currently undergoing basic standardization in 3GPP. In general, E-UMTS may be referred to as a Long Term Evolution (LTE) system. For details of the technical specifications of UMTS and E-UMTS, refer to Release 7 and Release 8 of the "3rd Generation Partnership Project; Technical Specification Group Radio Access Network", respectively.

Referring to FIG. 1, an E-UMTS is located at an end of a user equipment (UE), a base station (eNode B; eNB), and a network (E-UTRAN) and connected to an external network (Access gateway). Gateway; AG). The base station may transmit multiple data streams simultaneously for broadcast service, multicast service and / or unicast service.

[5] One or more cells exist in one base station. SAL is set to one of the bandwidth of 1.44, 3, 5, 10, 15, 20Mhz, etc. to provide a downlink or uplink transmission service to multiple terminals. Different cells may be configured to provide different bandwidths. The base station controls data transmission and reception for a plurality of terminals. The base station transmits downlink scheduling information to downlink (DL) data to the corresponding terminal. It informs the time / frequency domain, data, data size, and HARQ (Hybrid Automatic Repeat and reQuest) related information. In addition, the base station transmits uplink scheduling information to the terminal for uplink (UL) data and informs the time / frequency domain, encoding, data size, HARQ related information, etc. that the terminal can use. An interface for transmitting user traffic or control traffic may be used between base stations. The core network (CN) may consist of an AG and a network node for user registration of the terminal. The AG manages the mobility of the UE in units of TA Tracking Areas consisting of a plurality of cells.

[6] Wireless communication technology has been developed to LTE based on WCDMA, but the demands and expectations of users and operators are continuously increasing. In addition, as other radio access technologies continue to be developed, new technological advances are required to be competitive in the future. Reduced cost per bit, increased service availability, flexible use of frequency bands, simple structure and open interface, and adequate power consumption of the terminal are required.

[Detailed Description of the Invention]

[Technical problem]

An object of the present invention is to provide a method and apparatus for sharing radio resource information in a wireless communication system.

[8] The technical problems to be achieved in the present invention are not limited to the above technical problems, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description. Could be.

Technical Solution

[9] A method of sharing radio resource information of a cell in a multi-sal radio communication system, which is an aspect of the present invention for solving the above problems, transmits radio resource information to a neighbor cell. Doing; And receiving an acknowledgment message for the radio resource information from the neighbor cell, wherein the radio resource information includes information for changing a radio resource usage of a specific radio resource region. The acknowledgment message is a message indicating whether the radio resource usage change is allowed in the neighbor cell.

In addition, the acknowledgment message may be determined in the neighbor cell based on at least one of an uplink-downlink communication load state of the neighbor cell and a predicted interference amount on the specific radio resource region.

Further, the acknowledgment message may be transmitted based on a predefined physical wireless channel or an X2 interface.

Further, the specific radio resource region may be configured such that the neighbor cell does not perform uplink-downlink communication.

[13] The acknowledgment message may further include indicating that radio resource usage change is not permitted on the specific radio resource region, and receiving recommended radio resource usage change information from the neighboring cell. can do.

Further, the radio resource information includes information on at least one candidate uplink-downlink configuration (UL-DL configuration), and the confirmation message, the at least one candidate uplink-downlink configuration It may be characterized by including the information on the specific uplink-downlink configuration allowed in the neighbor cell.

Further, the adjacent cell may be a cell in which a time synchronization difference value with the cell is equal to or less than a predetermined threshold value.

Furthermore, the radio resource information may include information on the number of subframes for which the use of the radio resource is changed.

In addition, the specific radio resource region may include a radio resource for transmitting and receiving a specific reference signal. Furthermore, the specific reference signal may be configured according to predefined reference signal configuration information. The reference signal configuration information may include at least one of the number of antenna ports, a physical cell identifier, a virtual cell identifier, a type of reference signal, a configuration index, and transmission power of the reference signal. can do.

Further, the radio resource information may include at least one of a use of a subframe at a specific time point and a subframe at the specific time point, wherein the radio resource information is an uplink of the serving cell. Link control channel transmission The method may further include information about an area or a specific reference signal transmission area.

[19] Furthermore, the radio resource usage change may be configured to use a radio resource configured for uplink communication for downlink communication or to use a radio resource configured for downlink communication for uplink communication. You can do

[20] The radio resource information sharing method may further include information on resource utilization rate of the specific radio resource region.

According to another aspect of the present invention for solving the above-mentioned problem, a method of sharing radio resource information in a multi-cell wireless communication system includes: receiving radio resource information from a specific cell; Determining whether to allow a change in radio resource usage of the specific cell based on the radio resource information and an uplink-downlink communication load state; And transmitting a confirmation message indicating whether to allow radio resource usage change to the specific cell, wherein the radio resource information is information for changing the radio resource usage of a specific radio resource region. Can be.

Advantageous Effects

According to the present invention, in the case of dynamically changing a radio resource according to a system load in a wireless communication system, a plurality of cells share information about the radio resource so that efficient communication can be performed.

[23] Effects obtained in the present invention are not limited to the above-mentioned effects, and other effects not mentioned above are clearly understood by those skilled in the art from the following description. Could be. [Brief Description of Drawings]

The accompanying drawings, which are included as a part of the detailed description to help understand the present invention, provide an embodiment of the present invention and together with the description, describe the technical idea of the present invention.

1 illustrates an E-UMTS network structure as an example of a wireless communication system. FIG. 2 illustrates a control plane and a user plane structure of a radio interface protocol between a UE and an E-UTRAN based on the 3GPP radio access network standard.

3 shows physical channels used in a 3GPP LTE system and a general signal transmission method using the same.

4 shows the structure of a radio frame used in an LTE system.

5 shows a resource grid for a downlink slot.

6 illustrates a structure of a downlink subframe.

7 shows a structure of an uplink subframe used in LTE.

8 shows an example of performing CoMP.

9 illustrates an interference problem between cells generated when information on a radio resource usage change is not shared between cells.

10 illustrates a method in which a specific cell shares radio resource information according to the present invention.

11 illustrates a data flow for sharing radio resource information between a plurality of cells according to an embodiment of the present invention.

12 illustrates an embodiment of performing radio resource usage change between cells according to the present invention.

13 shows a synchronized cell set configured according to the present invention.

[38] Figure 14 illustrates a base station and user equipment that can be applied to an embodiment of the present invention.

[Form for implementation of invention]

[39] The technology of the following is CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (t ime division multiple 'access), 0FDMA (orthogonal frequency division multiple access), SC ~ FDMA (single carrier frequency division It can be used in various wireless access systems such as multiple access. CDMA may be implemented by a radio technology such as UTRACUniversal Terrestrial Radio Access) or CDMA2000. TDMA is GSKGlobal System for Mobile communication on s / GPRS (General Packet Radio) It can be implemented with wireless technologies such as Service / EDGE (Enhanced Data Rates for GSM Evolution). 0FDMA may be implemented in a wireless technology such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, Evolved UTRA (E-UTRA), and the like. UTRA is part of the Universal Mobile Telecommunications System (UMTS). 3GPP LTEdong term evolution (3GPP) is part of Evolved UMTS (E-UMTS) using E-UTRA, which employs 0FDMA in downlink and SC-FDMA in uplink. LTE-A (Advanced) is an evolution of 3GPP LTE.

For clarity, the following description will focus on 3GPP LTE / LTE-A, but the technical spirit of the present invention is not limited thereto. In addition, specific terms used in the following description are provided to help the understanding of the present invention, and the use of such specific terms may be changed to other forms without departing from the technical spirit of the present invention. '

FIG. 2 is a diagram illustrating a control plane and a user plane structure of a radio interface protocol between a UE and E—UTRAN based on the 3GPP radio access network standard. The control plane refers to a path through which control messages used by a user equipment (UE) and a network to manage a call are transmitted. The user plane refers to a path through which data generated at an application layer, for example, voice data or Internet packet data, is transmitted.

The physical layer, which is the first layer, provides an information transfer service to an upper layer by using a physical channel. The physical worm is connected to the upper layer of the medium access control layer through a trans antenna port channel. Data is moved between the media access control layer and the physical layer through the transport channel. Data moves between the physical layer at the transmitting side and the physical layer at the receiving side. The physical channel utilizes time and frequency as radio resources. In detail, the physical channel is modulated in a 0rthogonal frequency division multiple access (0FDMA) scheme in the downlink, and modulated in a single carrier frequency division multiple access (SC-FDMA) scheme in the uplink. The medium access control (MAC) layer of the second layer provides a service to a radio link control (RLC) layer, which is a higher layer, through a logical channel. The RLC layer of the second layer supports reliable data transmission. The function of the RLC layer may be implemented as a functional block inside the MAC. The Packet Data Convergence Protocol (PDCP) layer of the second layer performs a header compression function to reduce unnecessary control information for efficiently transmitting IP packets such as IPv4 or IPv6 in a narrow bandwidth wireless interface.

A radio resource control (RRC) layer located at the bottom of the third layer is defined only in the control plane. The RRC layer is responsible for the control of logical channel transport channels and physical channels in connection with configuration, reconfiguration (Re—conf igurat i) and release of radio bearers (RBs). RB means a service provided by the second layer for data transmission between the terminal and the network. To this end, the RRC layers of the UE and the network exchange RRC messages with each other. If there is an RRC connected (RRC Connected) between the terminal and the RRC layer of the network, the terminal is in the RRC connected mode (Connected Mode), otherwise it is in the RRC idle mode (Idle Mode). The NAS (Non-Access Stratum) layer above the RRC layer performs functions such as session management and mobility management.

One cell constituting the base station (eNB) is set to one of bandwidths such as 1.4, 3, 5 ᅳ 10, 15, 20 MHz, and provides downlink or uplink transmission services to various terminals. Different cells may be configured to provide different bandwidths.

A downlink transport channel for transmitting data from a network to a UE includes a broadcast channel (BCH) for transmitting system information, a paging channel (PCH) for transmitting a paging message, and a downlink shared channel (SCH) for transmitting user traffic or a control message. ). Traffic or control messages of the downlink multicast or broadcast service may be transmitted through the downlink SCH or may be transmitted through a separate downlink MQKMulticast Channel. Meanwhile, the uplink transmission channel for transmitting data from the terminal to the network includes a random access channel (RAC) for transmitting an initial control message and an uplink shared channel (SCH) for transmitting user traffic or a control message. Logical channel that is located above the transport channel and mapped to the transport channel Channels include a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multi icast control channel (MCCH), a multicast traffic channel (MTCH), and the like.

3 is a diagram for explaining physical channels used in a 3GPP LTE system and a general signal transmission method using the same.

In operation S301, a user equipment that is powered on again or enters a new cell performs an initial cell search operation such as synchronizing with a base station. To this end, the user equipment receives a Primary Synchronization Channel (P-SCH) and a Secondary Synchronization Channel (S-SCH) from the base station, synchronizes with the base station, and obtains information such as a cell ID. Thereafter, the user equipment may receive a physical broadcast channel from the base station to obtain broadcast information in a cell. On the other hand, the user equipment receives the downlink RS (Downlink Reference Signal, DL RS) in the initial cell search step the downlink channel ^state: it is possible to check ¾.

[49] After completing the initial cell search, the user equipment performs physical downlink control channel (PDCCH) and physical downlink control channel (PDSCH) according to physical downlink control channel information in step S302. Receive a more detailed system information can be obtained.

Thereafter, the user equipment may perform a random access procedure such as steps S303 to S306 to complete the access to the base station. To this end, the user equipment transmits a preamble through a physical random access channel (PRACH) (S303), and a physical downlink control channel and a physical downlink shared channel to the preamble for the preamble. The answer message may be received (S304). In case of contention-based random access, a content ion resolution procedure such as transmitting an additional physical random access channel (S305) and receiving a physical downlink control channel and a corresponding physical downlink shared channel reception (S306) may be performed. Can be.

The user equipment which has performed the above-described procedure is then subjected to a physical downlink control channel / physical downlink shared channel (S307) and a physical uplink shared channel as a general uplink / downlink signal transmission procedure. , PUSCH) / Physics A physical uplink control channel (PUCCH) transmission (S308) may be performed. The control information transmitted from the user equipment to the base station is collectively referred to as uplink control information (UCI). UCI includes HARQ AC / NACK (Hybrid Automatic Repeat and reQuest Acknowledgment / Negative ACK) SR (Scheduling Request), Channel State Information (CS I), and the like. In the present specification, HARQ AC / NACK is simply referred to as HARQ-ACK or ACK / NACK (A / N). HARQ-ACK includes at least one of positive ACK (simply ACK), negative ACK (NACK :), DTX, and NACK / DTX. The CSI includes a CQKChannel Quality Indicator (PMQ), a PMK Precoding Matrix Indicator (AR), a Rank Indication (RI), and the like. UCI is generally transmitted through PUCCH, but can be transmitted through PUSCH when control information and traffic data should be transmitted at the same time. In addition, the UCI can be aperiodically transmitted through the PUSCH by the network request / instruction.

4 is a diagram illustrating a structure of a radio frame used in an LTE system.

Referring to FIG. 4, in the Salola OFDM wireless packet communication system, uplink / downlink data packet transmission is performed in subframe units, and one subframe includes a plurality of OFDM symbols. It is defined as a time interval. The 3GPP LTE standard supports a type 1 radio frame structure applicable to FDE Frequency Division Duplex (FDE) and a type 2 radio frame structure applicable to Time Division Duplex (TDD).

[54] Figure 4 (a) illustrates the structure of a type 1 radio frame. The downlink radio frame consists of 10 subframes, and one subframe consists of two slots in the time domain. The time taken for one subframe to be transmitted is called a TTK transmission ime interval. For example, one subframe may have a length of 1 ms, and one slot may have a length of 0.5 ms. One slot includes a plurality of 0FDM symbols in the time domain and includes a plurality of resource blocks (RBs) in the frequency domain. In the 3GPP LTE system, since 0FDMA is used in downlink, the 0FDM symbol represents one symbol period. The 0FDM symbol may also be called an SC-FDMA symbol or symbol interval. It may be. A resource block (RB) as a resource allocation unit may include a plurality of consecutive subcarriers in one slot.

The number of OFDM symbols included in one slot may vary depending on the configuration of a cyclic prefix (CP). CPs have extended CPs and standard CPC normal CPs. For example, when an OFDM symbol is configured by a standard CP, the number of OFDM symbols included in one slot may be seven. When the OFDM symbol is configured by an extended CP, since the length of one OFDM symbol is increased, the number of OFDM symbols included in one slot is smaller than that of the standard CP. In the case of an extended CP and, for example, the number of OFDM symbols included in one slot may be six. In case of unstable channel conditions such as when the user equipment moves at a high speed, an extended CP may be used to further reduce interference between symbols.

When a standard CP is used, one slot includes 7 OFDM symbols, and thus, one subframe includes 14 OFDM symbols. In this case, the first up to three OFDM symbols of each subframe may be allocated to a physical downlink control channel (PDCCH), and the remaining OFDM symbols may be allocated to a physical do channel link shared channel (PDSCH).

4B illustrates a structure of a type 2 radio frame. The type 2 radio frame consists of two half frames, each half frame comprising four general subframes including two slots, a down link pilot time slot (DwPTS), and a guard period (GP). ) And a special subframe including an UpPTSCUpHnk Pilot Time Slot.

In the special subframe, DwPTS is used for initial cell search, synchronization, or channel estimation in a user equipment. UpPTS is used for channel estimation at base station and synchronization of uplink transmission of user equipment. That is, DwPTS is used for downlink transmission and UpPTS is used for uplink transmission. In particular, UpPTS is used for PRACH preamble or SRS transmission. In addition, the guard interval is a section for removing interference caused by the uplink due to the multipath delay of the downlink signal between the uplink and the downlink. [59] As for the special subframe, the current 3GPP standard document defines the following configuration. In Table 1, DwPTS and UpPTS (^ ^{= 1} / ^ ⁵⁰⁰ 0x2048) are shown, and the rest of the area is set as a protection interval.

[60] [Table 1]

Meanwhile, the structure of the type 2 radio frame, that is, the UL / DL link subframe configuration (UL / DL configuration) in the TDD system is shown in Table 2 below.

[62] [Table 2]

In Table 2, D denotes a downlink subframe, U denotes an uplink subframe, and S denotes the special subframe. In addition, Table 2 also shows a downlink-uplink switching period in the uplink / downlink subframe configuration in each system.

The structure of the radio frame described above is merely an example, and the number of subframes included in the radio frame, the number of slots included in the subframe, and the number of symbols included in the slot may be variously changed.

5 illustrates a resource grid for a downlink slot. Referring to FIG. 5, the downlink slot includes N _symb OFDM symbols in the time domain and N resource blocks in the frequency domain. Since each resource block includes subcarriers, the downlink slot includes N × N subcarriers in the frequency domain. FIG. 5 illustrates that the downlink slot includes 7 OFDM symbols and the resource block includes 12 subcarriers, but is not necessarily limited thereto. For example, the number of OFDM symbols included in the downlink slot may be modified according to the length of a cyclic prefix (CP).

Each element on the resource grid is called a resource element (RE), and one resource element is indicated by one OFDM symbol index and one subcarrier index. One RB is composed of N _lbX N ^B resource elements. The number N of resource blocks included in the downlink slot depends on a downlink transmission bandwidth set in a cell.

6 illustrates a structure of a downlink subframe.

[69] Referring to FIG. 6, up to three (4) OFDM symbols located at the front of the first slot of a subframe are indicated in a control region to which a control channel is allocated. The remaining OFDM symbols correspond to data regions to which the Physical Downlink Shared Channel (PDSCH) is allocated. Examples of a downlink control channel used in LTE include a physical control format indicator channel (PCFICH), a physical downlink control channel (PDCCH), a physical hybrid ARQ indicator channel (PHICH), and the like. The PCFICH is transmitted in the first OFDM symbol of a subframe and carries information on the number of OFDM symbols used for transmission of control channels within the subframe. PHICH carries a HARQ ACK / NACK (Hybrid Automatic Repeat request acknow 1 edgment / negat i ve ^~ acknow 1 edgment) signal as a response ^to uplink transmission.

Control information transmitted through the PDCCH is called DCKDownlink Control Information. The DCI includes resource allocation information and other control information for the user device or the user device group. For example, the DCI includes uplink / downlink scheduling information, uplink transmission (Tx) power control command, and the like.

[71] The PDCCH includes a transmission format and resource allocation information of a downlink shared channel (DL-SCH) and an uplink shared channel (UL-SCH). Resource allocation information of higher-layer control messages, such as transmission format and resource allocation information of the UE, paging information on the paging channel (PCH), system information on the DL-SCH, and random access responses transmitted on the PDSCH. It carries Tx power control command set, Τχ power control command, activation indication information of VoIPCVoice over IP) for individual user devices in the device group. A plurality of PDCCHs may be transmitted in the control region. The user equipment may monitor the plurality of PDCCHs. The PDCCH is transmitted on an aggregation of one or a plurality of consecutive control channel elements (CCEs). CCE is a logical allocation unit used to provide a PDCCH with a coding rate based on radio channel conditions. The CCE corresponds to a plurality of resource element groups (REGs). The format of the PDCCH and the number of PDCCH bits are determined according to the number of CCEs. The base station determines the PDCCH format according to the DCI to be transmitted to the user equipment, and adds a cyclic redundancy check (CRC) to the control information. The CRC is masked with an identifier (eg RNTKradio network temporary ident if ier) depending on the owner of the PDCCH or the purpose of use. For example, when the PDCCH is for a specific user equipment, an identifier (eg, cell-R TI (C-RNTI)) of the corresponding user equipment may be masked to the CRC. If the PDCCH is for a paging message, the paging identifier (eg paging-RNTI (P—RNTI)) may be masked in the CRC. When the PDCCH is for system information (more specifically, a system information block (SIC)), a system information RNTI (SI-RNTI) may be masked to the CRC. When the PDCCH is for random access voice answer, RA-RNTI (random access-RNTI) may be masked to the CRC.

7 illustrates a structure of an uplink subframe used in LTE.

Referring to FIG. 7, an uplink subframe includes a plurality of slots (eg, two). The slot may include different numbers of SC-FDMA symbols according to the CP length. The uplink subframe is divided into a data region and a control region in the frequency domain. The data area includes a PUSCH and is used to transmit a data signal such as voice. The control region includes a PUCCH and is used to transmit uplink control information (UCI). The PUCCH includes RB pairs located at both ends of the data region on the frequency axis and hops to a slot boundary.

[74] The PUCCH may be used to transmit the following control information. [75]-SR (Scheduling Request): Information used to request an uplink UL-SCH resource. It is transmitted using 00K (0n-0ff Keying) method.

HAR76 ACK / NACK: This is a response signal for a downlink data packet on a PDSCH. Indicates whether the downlink data packet was successfully received. ACK / NACK 1 bit is transmitted in response to a single downlink codeword, and ACK / NACK 2 bits are transmitted in response to two downlink codewords.

[77]-Channel State Information (CSI): Feedback information on a downlink channel. The CSI includes a CQKChannel Quality Indicator (MQ0), and feedback information related to MIM0 (Mult iple Input Multiple Output) includes a rank indicator (RI), a PMKPrecoding Matrix Indicator (RI), a PTKPrecoding type indicator, and the like. 20 bits are used per subframe.

The amount of control information JCI) that a user equipment can transmit in a subframe depends on the number of SC-FDMAs available for control information transmission. SC-FDMA available for control information transmission means the remaining SC-FDMA symbol except for the SC-FDMA symbol for transmission of the reference signal in the subframe, and in the case of the subframe in which the Sounding Reference Signal (SRS) is set, the last subframe SC-FDMA symbols are also excluded. The reference signal is used for coherent detection of the PUCCH.

Hereinafter, CoMP (Cooperative Multipoint Transmission / Recept ion) will be described.

[80] The system after LTE-A intends to introduce a method for improving the performance of the system by enabling cooperation between multiple cells. In this way cooperation multipoint transmission / reception ^{(Cooperative Multipoint Transmission / Reception '-} CoMP) is called. CoMP refers to a method in which two or more base stations, access points, or cells cooperate with each other to communicate with a terminal in order to facilitate communication between a specific terminal, a base station, and an access point or a cell. In the present invention, a base station, an access, or a cell may be used in the same sense.

In general, in a multi-cell environment having a frequency reuse factor of 1, due to inter-cell interference (ICI), the performance and average sector yield of a UE located in a cell boundary are reduced. Can be reduced. In order to reduce such ICI, in the existing LTE system, partial frequency through terminal specific power control Using simple passive techniques such as fractional frequency reuse (FFR), a method has been applied to ensure that UEs located in the sal-boundary have adequate yield performance in an environment limited by interference. However, rather than reducing the use of frequency resources per cell, it may be more desirable to reduce the ICI or reuse the ICI as a signal desired by the terminal. In order to achieve the above object, CoMP transmission scheme can be applied.

8 shows an example of performing CoMP. Referring to FIG. 8, the wireless communication system includes a plurality of base stations BS1, BS2, and BS3 that perform CoMP and a terminal. A plurality of base stations (BS1, BS2 and BS3) performing CoMP can efficiently transmit data to the terminal in cooperation with each other. CoMP can be divided into two types according to whether data is transmitted from each base station performing CoMP as follows:

[83]-Joint Processing (CoMP-JP) [84]-CoMP-CS / CB, CoMP Cooperative scheduling: CoMP-CS

In the case of CoMP-JP, data to one terminal is simultaneously transmitted from each base station that performs) ΜΡ to the terminal, and the terminal combines signals from each base station to improve reception performance. That is, the CoMP-JP technique may use data at each point (base station) of the CoMP cooperative unit. CoMP cooperative unit means a set of base stations used in a cooperative transmission scheme. The JP technique can be classified into a joint transmission technique and a dynamic cell selection technique.

The joint transmission scheme refers to a scheme in which a PDSCH is transmitted from some or all of a plurality of points () MP cooperative units at a time. That is, data transmitted to a single terminal may be simultaneously transmitted from a plurality of transmission points. According to the joint transmission technique, the quality of a received signal can be improved coherently or non-coherently, and can also actively cancel interference with other terminals. .

[87] The dynamic cell selection scheme refers to a scheme in which PDSCH is transmitted from one point (of CoMP cooperative unit) at a time. That is, data transmitted to a single terminal at a specific point in time is transmitted from one point, and another point in the cooperative unit at that point in time. Does not transmit data to the terminal, and a point for transmitting data to the terminal may be dynamically selected.

On the other hand, in the case of CoMP-CS, data to one terminal is transmitted through one base station at any moment, and scheduling or beamforming is performed so that interference by the other base station is minimized. That is, according to the CoMP-CS / CB scheme, CoMP cooperative units may cooperatively perform beamforming of data transmission for a single terminal. In this case, data is transmitted only in the serving cell, but user scheduling / beamforming may be determined by coordination of cells of the corresponding C in the WP cooperative unit.

On the other hand, in the case of uplink, coordinated multi-point reception means receiving a signal transmitted by coordination of a plurality of geographically separated points. The MP scheme applicable to uplink may be classified into Joint Reception (JR) and coordinated scheduling / beamforming (CS / CB).

[90] The JR scheme means that a signal transmitted through a PUSCH is received at a plurality of reception points, and the CS / CB scheme means that a PUSCH is received only at one point, but user scheduling / beamforming is performed in cells Means determined by the adjustment.

Hereinafter, interference between a plurality of cells will be described.

In the case where a part of coverage of two base stations overlaps, such as when two base stations (for example, base station # 1 and base station # 2) are adjacent to each other, another base station is served with respect to a terminal served from one base station. Strong downlink signals from can cause interference. When inter-cell interference occurs as described above, inter-cell interference can be reduced by using the inter-cell cooperative signaling method between two base stations. In various embodiments of the present invention described below, it is assumed that a signal is smoothly transmitted and received between two base stations that interfere with each other. For example, there is a wired / wireless link (for example, a backhaul link or an Un interface) that has good transmission conditions such as transmission bandwidth or time delay between two base stations, so that the reliability of transmitting and receiving cooperative signals between base stations is high. Assume a high case. In addition, the time synchronization between the two base stations may be matched within an allowable error range (for example, the boundary between the downlink subframes of the two base stations interfering with each other is aligned). Case), it may be assumed that the difference between subframe boundaries between two base stations is clearly recognized.

Referring to FIG. 8 again, base station # 1 (BS # 1) is a macro base station serving a wide area with high transmission power, and base station # 2 (BS # 2) serves a low area with low transmission power. Micro base station (eg, pico base station). As illustrated in FIG. 8, when a UE (UE) located in a cell boundary region of the base station # 2 receives strong interference from the base station # 2, effective communication may be difficult without proper inter-cell cooperation. have.

In particular, when a large number of terminals are connected to the base station # 2, which is a micro base station having low power, and the macro base station # 1 attempts to distribute the load for providing the service, The situation is likely to occur. For example, when the terminal intends to select a serving base station, a predetermined adjustment value (bias value) is added to the reception power from the micro base station, and the adjustment value is not added to the reception power from the macro base station. In this manner, the reception power of the downlink signal from each base station can be calculated and compared, and as a result, the terminal can select a base station providing the highest downlink reception power as the serving base station. Accordingly, more terminals can be connected to the micro base station. The downlink signal strength actually received by the terminal can be selected as the serving base station even though the signal from the macro base station is much stronger, and the terminal connected to the micro base station experiences strong interference from the macro base station. Can be done. In this case, when the terminals located at the boundary of the micro base station are not provided with separate inter-cell cooperation, it may be difficult to perform a proper operation due to strong interference from the macro base station.

[95] In order to perform an effective operation even in the presence of intercell interference, appropriate cooperation should be made between two base stations that exchange intercell interference, and a signal for enabling such cooperative operation is transmitted and received through a link between two base stations. Can be. In this case, when the inter-cell interference occurs between the macro base station and the micro base station, the macro base station controls the inter-cell cooperative operation, and the micro base station may perform an appropriate operation according to the cooperative signal informed by the macro base station. The above-described inter-cell interference occurrence situation is merely exemplary, and embodiments described in the present invention are cases where inter-cell interference occurs in a situation different from the above (for example, inter-cell interference between HeNB of CSG scheme and macro base station of 0SG scheme). In this case, it is obvious that the micro base station causes interference and the macro base station is subjected to the interference, or when the inter-cell interference is present between the micro base stations or between the macro base stations.

Furthermore, in the present invention, when a particular cell dynamically changes a radio resource use (for example, uplink resource or downlink resource) to a purpose of downlink or uplink communication according to a change in its load state, the specific cell is adjacent to the neighbor. In cooperation with the cell, we propose a method for efficiently changing the radio resource usage.

When a specific cell performs radio resource usage change according to its load state change, it is necessary to inform neighboring cells of related information. That is, if a particular cell does not share information about radio resource usage with neighboring cell (s), the particular cell and neighboring cells have a lot of interference due to different communication directions (eg, terminal-to-terminal interference base station). -Base station interference, etc.), and may cause a problem in which an arbitrary cell performs appropriate quality communication.

Therefore, in the following description, an interference measurement between a base station and a base station in which a specific cell is affected by its dynamic radio resource re-use operation, and an interference measurement result feedback operation (for example, For example, the method for identifying through the X2 interface between the base stations sharing interference measurement results), etc. will be described.

9 is a reference diagram for explaining an interference problem between cells generated when information on a radio resource usage change is not shared between cells.

In FIG. 9, as cell #A increases its downlink data communication load, cell #A sets uplink-downlink subframe configuration to uplink-downlink subframe configuration # 1 (“DSUUDDSUUD”). In this case, the case is changed from UL to DL subframe configuration # 2 (“DSUDDDSUDD”).

[102] In FIG. 9, if cell #A does not inform cell #B of its dynamic radio resource usage change, UE #A performing downlink communication with cell #A has a specific time point (eg, For example, SF # 13, SF # 18, etc.) may perform uplink communication with cell #B. Receiving UE-to-UE interference from UE #B to perform, UE # 8 performing uplink communication with UE # 8 has a UE # at a specific time point (ie, SF _' SF # 18). from the ^"cell #A to perform the a and downlink communication base station will receive the base station interference _(e NB--eNB to interference) interference.

Therefore, when a specific cell dynamically changes the radio resource usage according to a change in its load state, an additional cell cooperation method is required to ensure the communication quality of not only the corresponding cell but also the neighboring cell in an appropriate state. The present invention proposes a preferred method of cooperation between cells when a dynamic radio resource usage change method is applied.

Referring to FIG. 10, the radio resource information is transmitted to a neighbor cell (S1001). That is, according to the present invention, a specific cell dynamically changes the radio resource usage according to a change in load state. In this case, the cell may inform neighboring cells of information on the radio resource or radio resource that is likely to be changed (for example, the position on the frequency / time resource area, information on the direction of use change, etc.). Can be.

In addition, the information on the radio resource may include a changed or newly defined UL-DL configuration, and may include a static resource or a flexible resource. You may. For example, in the present invention, resources may be defined as time / frequency resources, static resources may be defined as static subframes, and dynamic resources may be defined as dynamic subframes.

In the present invention, a static resource is used for a purpose of existing radio resource (for example, downlink communication or uplink communication) or used according to a predefined use of a radio resource. Can be defined as a resource. Accordingly, the static resource in the present invention is a resource used for the same purpose as the resource use on the SIB, or a resource used for the same purpose as the purpose set in the previous radio resource reset period, or a predefined uplink. Reference to the downlink / resource used for the same purpose as on the HARQ timeline. Uplink / Downlink Reference It may be defined as one of resources used for the same purpose as the purpose of uplink-downlink configuration.

In addition, in the present invention, a flexible resource is defined as a resource used to dynamically change the use of a radio resource. For example, a resource used for a purpose other than the resource use on the SIB, or a resource used for a different purpose than the purpose set in the previous radio resource use resetting period, or a predefined uplink / downlink reference HARQ. Resources used for purposes other than those on the Reference HARQ timeline, black for purposes other than those on the predefined UL / DL reference UL-DL configuration It can also be defined as one of the resources.

Therefore, in the present invention, at least one or more neighbors using at least one of the above-described information on the UL-DL configuration, a static resource, and a flexible resource. The cell may be informed about the radio resource.

The neighbor cell receiving the information about the radio resource may have its current load state (for example, a downlink or uplink data communication load is high), or a specific cell may dynamically change the use of the radio resource. Based on the amount of interference predicted or calculated to occur in a case, a confirmation message or a confirmation response message about a dynamic radio resource change of a specific cell may be informed to a specific cell. There is (S1003).

[111] In this case, the acknowledgment message (or acknowledgment message) that the neighbor cell informs the specific cell about the change of radio resource usage transmitted by the specific cell and the neighbor cell is a predefined physical radio channel or X2 interface. Can be transmitted based on. In addition, the acknowledgment message or acknowledgment message of the present invention may be transmitted only when the neighbor cell permits the change of radio resource usage of a specific cell or may be used to indicate whether to allow the change of radio resource usage of a specific cell.

Therefore, according to the present invention, when the neighbor cell allows the radio resource usage change of a specific cell, the neighbor cell is intentionally in the radio resource region that is likely to receive high interference or high interference from the specific cell. Do not perform communication (e.g., avoiding interference in the time resource domain) or if such interference exists Even in this state, only terminals capable of performing communication (eg, terminals located inside a cell) may be limitedly scheduled. For example, the neighbor cell may be configured not to inform the specific cell of information on the interference mitigation method (or interference avoidance method) performed in the region where the radio resource usage change of the specific cell is performed. In addition, the application of the interference mitigation method (or interference avoidance method) in the area where the radio resource usage change of the neighbor cell is performed may have an effect on the communication of a specific cell or dynamically change the radio resource of the specific cell. If there is a possibility of affecting the neighboring cell, the neighboring cell may be configured to inform the specific cell about the interference mitigation method (or interference avoidance method) that it applies. Furthermore, a specific cell that has received information on an interference mitigation method (or interference avoidance method) from a neighbor cell may then consider information on the interference mitigation method in its radio resource use change operation and communication in a specific direction. .

In addition, according to the present invention, if a neighbor cell does not allow a radio resource usage change of a specific cell, the specific cell may be configured not to perform its radio resource usage change operation.

[114] In addition, when a neighbor cell does not allow a radio resource change of a specific cell, the neighbor cell is predicted or calculated to occur when its current load state or a specific cell dynamically changes the radio resource usage. Considering the amount of interference, it may be possible to inform the specific cell of the appropriate ended radio resource change information. For example, the recommended radio resource usage change information may be transmitted to a specific cell based on a predefined physical radio channel or an X2 interface to a specific cell. According to the present invention, the specific cell receiving the recommended radio resource usage change information from the neighbor cell transmits the updated radio resource usage change information back to the neighboring cell by reflecting the received information (that is, the recommended radio resource usage change information). Can also be.

11 is a reference diagram for explaining a data flow for sharing radio resource information between a plurality of cells according to an embodiment of the present invention.

In FIG. 11, it is assumed that radio resource information is shared in a wireless communication system including sal #A and sal #B. According to the present invention, cell #A transmits information related to a radio resource usage change to cell #B (S1101).

Accordingly, in cell #B, the state of cell #B, that is, the uplink-downlink communication load state of cell # 8, and the use of a specific radio resource (eg, a subframe) in cell #A are changed. In this case, it is determined whether to change the radio resource usage in consideration of the expected interference amount and the like (S1103). For example, if cell #A intends to use a specific uplink subframe for downlink use, if it is determined that the amount of interference between cell # and cell # 8 does not cause a problem in communicating with cell # 8, cell # 八It may be determined whether to allow the use of the radio resource change.

Accordingly, the cell may transmit whether to allow the radio resource usage change determined in S1103 and information related to the radio resource usage change to the cell.

(S1105).

Further, when the present invention is applied to a network composed of a plurality of cells, the radio resource usage change operation of the specific cell or the radio resource usage change allowance operation may be sequentially performed in the radio resource usage change operation of the neighboring cell and the communication in a specific direction. Will affect. Therefore, a specific cell may select neighbor cells that are affected by the radio resource usage change operation or the radio resource usage change allowance operation, the interference measurement operation between the base station and the base station, and the interference measurement result feedback operation (for example, And sharing interference measurement results through the X2 interface between base stations.

In the present invention, the radio resource usage change may be performed based on a predefined time / frequency unit (for example, subframe unit) or an existing uplink-downlink subframe configuration unit.

For example, when a radio resource use change is performed based on an existing uplink-downlink subframe setting unit, a specific cell is one specific uplink that is likely to change or is likely to change. The downlink subframe configuration information may be informed to the neighbor cell. Alternatively, a particular cell may inform neighboring cells of information on a plurality of uplink-downlink subframe configuration candidates that it wants to change or is likely to change. In addition, the neighbor cell receiving the information on the radio resource usage change is based on the information on one specific uplink-downlink subframe configuration information or a plurality of uplink-downlink subframe configuration candidates. Information on the allowable uplink-downlink subframe configuration (or a set of uplink-downlink subframes) may be informed to a specific cell again.

[124] For example, in a heterogeneous network situation in which a macro cell and a pico cell are common, the uplink-downlink subframe setting # 1 in which the macro cell is fixed is applied and the pico cell is applied. If the uplink-downlink subframe configuration is dynamically changed according to its own load state, the macro cell may configure uplink-downlink subframe configuration candidates informed by the picocell, that is, uplink-downlink subframe configuration # 2. It is possible to inform that among the # 4, # 5, the uplink-downlink subframe configuration # 2, # 4 is allowed in consideration of its uplink data communication load state. As described above, when the radio resource usage change is performed based on the existing uplink-downlink subframe configuration unit according to the present invention, the radio resource usage change is previously defined in a time / frequency unit (for example, a subframe). It can be extended even if it is performed based on the unit).

In addition, according to the present invention, when receiving the information that the neighbor cell will perform radio resource use change from a particular cell to a specific communication direction, the neighbor cell is at least one allowable in consideration of its load condition It may be configured to inform specific cells of information on time / frequency radio resources. Here, the allowable time / frequency radio resource information may be configured based on a predefined time / frequency unit or an existing uplink-downlink subframe configuration unit.

For example, in a heterogeneous network situation in which the macro cell and the pico cell are common, the uplink-downlink subframe configuration # 1 in which the macro cell is fixed is applied, and the pico cell is uplink-down according to its load condition. Assume that the link subframe configuration is changed dynamically. In this case, if the picocell informs the macro cell that the load of the downlink data communication will increase and perform radio resource usage change in the downlink communication direction, the macro cell may indicate its uplink load state. In consideration of the allowable uplink-downlink subframe configuration # 2, # 4, # 5 (set) information may be known. 12 illustrates an embodiment of performing radio resource usage change between cells according to the present invention. It is assumed that cell #A and cell #B are initially set to uplink-downlink subframe setting # 1.

In FIG. 12, the cell # λ is an uplink-downlink subframe having a high weight of a downlink subframe that the cell # λ intends to change according to the proposed scheme in order to efficiently handle the increased downlink data communication load. Gives priority to frame setting # 2, # 4, # 5.

The cell # β receiving the uplink-downlink subframe configuration information having a high weight of the downlink subframe has received the uplink_downlink subframe received from the cell # Α in consideration of its uplink data communication load state. Among the frame configuration candidates, allowable uplink_downlink subframe configuration # 2 and # 4 information is informed to the cell # Α again.

[130] Finally, cell # Α configures an uplink-downlink subframe most suitable for its downlink load state among the allowable uplink-downlink subframe configuration # 2, # 4 received from cell # Β. Will be selected.

In addition, according to the present invention, when a specific cell informs a neighboring cell of a set of subframes to be used by using a predefined signal (eg, Χ2 interface), the corresponding use is changed. Resource Utilization information of a subframe set to be informed may also be set. Or, if a specific cell informs about a set of subframes that are likely to be repurposed, and informs the user through a predefined signal, the resource utilization information of a set of subframes that are likely to be repurposed is also informed. It can also be.

In the present invention, the resource utilization information may be used to substantially use the subframes at an arbitrary rate, either during the use-changed subframe set that the specific cell informs the neighboring cell or the subframe set that is likely to be changed. It may mean a measurement value for whether or not, or may mean a measurement value for whether corresponding subframes are used for communication with high probability.

In other words, according to the present invention, a specific cell may transmit four subframes (eg, SF # (n + K ₀ ), SF # (n + ki), SF # (n + k ₂ ), to an adjacent cell. Subframe consisting of SF # (n + k ₃ )) It is assumed that there is a set, and that the subframe set is used by changing the use of radio resources or is likely to be used. In this case a specific cell, a sub-frame set ^"with the information, any ratio can notify you of resource utilization information (for example, 50%), and, on the other neighboring cell receiving the information, is the four sub It can be seen that only two subframes among the frames have a high probability of being substantially used or used by a specific cell. Therefore, the neighbor cell may perform its own communication in consideration of the interference effect generated from two subframes that are substantially used or likely to be used by a specific cell.

Alternatively, the resource utilization information may be set to be limitedly valid only on the subframe set used for the repurposed use or the subframe set that is likely to be repurposed. For example, a subframe set black used for a repurposed use in a specific cell may be set to be limited to some of uplink subframes on the SIB. Of course, the resource utilization information may be configured to be limited to all of the uplink subframes.

In addition, according to the present invention, it is assumed that the neighbor cell receives the resource utilization information along with information on the set of subframes that are likely to be used or changed in use by changing the use of M subframes from a specific cell. do. The adjacent cell receiving the above-described information may be configured to grasp the location of the subframe that is substantially used by the specific cell based on the resource utilization information or is likely to be used based on a predefined rule. Can be. Accordingly, as an example of the rule, the usage of radio resources is preferentially changed and used based on a descending order or ascending order for a subframe index in the M subframes. It may be.

[136] For example, a sub cell having a high possibility of being used or repurposed by a neighbor cell having four subframes (ie, SF # 4, SF # 8, SF # 8, SF # 9) from a specific cell. In case of receiving 50% resource utilization information together with the frame aggregation information, the corresponding neighboring cell is determined by SF # 9 and SF # 8 according to the rule (for example, in descending order of subframe index). It can be assumed that the probability of use is high or the probability of use is high. Here, the setting for the descending order for the subframe index described above may be used or changed for use. Subframes having contiguous subframe in- stances in the high-performance subframe set are used for uplink immediately after the downlink use (ie, propagation delay of downlink communication and timing advance of uplink communication). (TA) prevents the overlapping of some areas of the subframe.

[137] In addition, according to the present invention, a specific cell transmits information about a set of subframes that are likely to be repurposed or used by a particular cell through a predefined signal (eg, an X2 interface). In this case, it may be configured to additionally inform the subframe position of the subframes that are substantially used or communicated in the form of a bitmap.

In addition, according to the present invention, a specific cell transmits a predefined signal (for example, X2 interface) to a neighbor cell by using information about a subframe set that is likely to be repurposed or used. In this case, the resource utilization information for each subframe that is likely to be used or repurposed may be additionally informed in the form of a bitmap or a predefined format. . Or, it may be configured to additionally inform Resource Utilization information of resource usage for each predefined subframe group that is used or is likely to be repurposed.

Here, the resource utilization information may be defined as indicating a measurement value for whether a subframe that is likely to be repurposed or repurposed is substantially used or more likely to be used for communication. In addition, the above-described examples of the present invention can be extended and applied even when dividing resources in the frequency domain into resource sets that are likely to be used or changed in usage.

In addition, according to the present invention, in order to efficiently support the dynamic change of radio resource usage of neighbor cells, a specific cell may have low transmission power or radio resources at a specific point in time when a specific cell is not used for a predetermined communication purpose. It may be configured to inform neighboring cells of at least one of radio resources of a specific time point to be used for local communication through a predefined signal.

For example, in a TDD system, adjacent cells that receive information about radio resources at a specific time point from a specific cell may have time synchronization differences or subframes between cells. The synchronization difference may be composed of cells smaller than a predefined threshold. That is, information on radio resources of a specific point in time at which a specific cell is not used for a predetermined communication or radio resources to be used for communication at low transmission power is informed to neighboring cells, and the neighboring cells are subframes at that point in time. By using them for different purposes according to their system load conditions, it is possible to prevent additional interference caused by time synchronization or subframe synchronization for subframes of a certain time assumed by a particular cell and neighbor cells. have.

According to the present invention, in a heterogeneous network situation in which macro cells and pico cells are common, pico cells are generated due to different communication directions between cells when the uses of radio resources are dynamically changed according to their load conditions. Interference can be avoided. That is, when a subframe at a specific time is used as a downlink without a cooperation between sals, the sal is used for downlink use, and the pico cell uses a subframe at that time for uplink use. The interference generated from the downlink communication of the macro cell comes in at a high level. On the other hand, according to the present invention, the picocell is based on information on radio resources at a specific time point not to be used for a predetermined communication purpose received from a macro cell or radio resources at a specific time point for communication with low transmission power. When the subframes of the view are repurposed and used, the interference received from the macro cell due to different communication directions can be avoided. For example, pico cells that have received information from a macro cell about subframes at a particular point in time that are not used for a predetermined communication purpose or that are to be used for communication with low transmission power, may assign subframes at a particular point in time to their load conditions. Depending on the application can be set to use.

In addition, in the present invention, the number of subframes at a specific time point that will not be used for a predetermined communication purpose in which a specific cell informs neighbor cells or the number of subframes at a specific time point to be used for communication at a low transmission power is specified. It can be set according to the load state of. That is, the number of subframes at a specific point in time is arbitrarily set by a specific cell, is set to a predetermined value previously defined for radio resource usage change operation of neighbor cells, or is set through a request of a neighbor cell, It can be established through negotiation between sals. Further, subframes of a specific time point not to be used for a predetermined communication purpose in which a specific cell informs neighboring cells, or subframes of a specific time point to be used for communication with low transmission power are flexible subframes. It can be defined as. The floating subframe may be implemented in the form of one of the following subframes: Blank Subframe, Almost Blank Subframe (ABS), Zero-Power ABS, Nonzero-Power ABS, and MBSFN.

Therefore, ABS or black information from a specific cell (eg, a macro cell) receives information on subframes configured in the form of MBSFN subframes or information on subframes configured in the above-described floating subframe. Adjacent cells (eg, pico cells) may be configured to use the corresponding subframes for any purpose according to their load condition. Here, the ABS subframe may be one of Zero— Power ABS or Nonzero-Power ABS.

In addition, when a downlink subframe on the SIB of a specific seal is defined as a floating subframe, exceptionally a specific reference signal (eg, CRS) transmitted on the existing downlink subframe in the corresponding floating subframe ) May be set to be transmitted identically. Here, the type of a specific reference signal configured to be transmitted on the floating subframe of the present invention may be a reference signal (for example, CRS or RRS / RRM (Radio Link Monitor / Radio Resource Management) operation of a legacy UE). CSI-RS). In addition, the ^' CRS configured to be transmitted on the floating subframe may be configured such that the CRS is transmitted in the MBSFN subframe, for example, the CRS is transmitted only in the PDCCH region without transmitting the CRS in the PDSCH region. Furthermore, the information or the floating subframe configuration associated with the radio resource of the specific time point described above may be shared through a predefined signal between the base station and the terminal.

In addition, when a downlink subframe on the SIB of a specific cell is defined as a floating subframe, a specific reference signal transmitted on the existing downlink subframe in the corresponding floating subframe (eg, CRS, CSI-RS) ) May be set to not be transmitted. Here, the information on whether the above-described setting is applied or the information on the reference signal set not to be transmitted in the floating subframe may be shared through a predefined signal between the base station and the terminal. In addition, in the present invention, the downlink subframe on the SIB of a specific cell is defined as a floating subframe, and a predetermined reference signal (eg, CRS) defined in advance in the corresponding floating subframe is transmitted. In this case, neighboring cells using the floating subframe for uplink or downlink communication are considered to be rate-matched (RM) black for the corresponding reference signal in consideration of interference from a specific reference signal of a specific cell transmitted on the floating subframe. Puncturing (PC) operation may be set to apply. Furthermore, the information on the floating subframe and rate-matching or puncturing thereof may be shared through a predefined signal between the base station and the terminal.

According to the present invention, configuration information on a specific reference signal transmitted on a floating subframe may inform a specific cell to neighbor cells through a predefined signal. For example, the configuration information for a specific reference signal of a specific cell may include at least one of the number of antenna ports, physical cell identifiers, virtual cell identifiers, reference signal types, configuration indexes, and transmit power of the reference signal. A particular cell can inform neighboring cells about this with a predefined signal. Alternatively, neighboring cells using a floating subframe in which a specific reference signal is transmitted for uplink or downlink data communication may have 0 at positions of Resource Elements (REs) in which the reference signal is transmitted in consideration of interference from the specific reference signal. May be set to be allocated. Further, configuration information of a specific reference signal Here, the application or application of the rule may be shared through a predefined signal between the base station and the terminal.

In addition, the specific cell may be configured to inform neighboring cells of information on the use of the corresponding floating subframes as well as information on the floating subframes. In this case, the use of floating subframes may be determined by a specific cell arbitrarily, or may be predefined or negotiated between cells, in consideration of information on uplink / downlink load states of individual neighbor cells received from a neighbor cell. Can be set.

[151] In addition, a specific cell may not only provide information about floating subframes to neighboring cells, but also may include a resource region (eg, a resource block (RB) or Subframe) It can be set to inform the information together. For example, a resource region that contains a lot of interference from a specific cell on a floating subframe may be a UL control channel (PUCCH) transmission region or a specific reference signal (eg, CRS or CSI-RS) transmission region of a particular cell. Specifically, the uplink control channel transmission region of a specific cell may be defined as a UCI (eg, UL A / N, CSKRI / PMI / CQD) transmission region on a floating subframe, and may refer to a specific reference. The signal transmission area may be defined as an area for transmitting a reference signal transmitted for the purpose of maintaining the RLM / RRM operation of an existing terminal on a floating subframe.

In addition, according to the present invention, when time synchronization between cells or synchronization of subframes is not correct, at a point in time when the above-described specific cell actually applies the updated uplink-downlink configuration together with information transmitted to an adjacent cell. Information can be given together. For example, the neighbor cell receiving the information about the radio resource from the specific cell, along with the response message for the updated uplink-downlink configuration information, the response message for the time when the updated uplink-downlink configuration is actually applied It can be set to transmit.

In addition, in the present invention, the information on the floating subframes that the specific cell informs the neighboring cells is adjacent to the difference value is smaller than the predefined threshold value based on the time synchronization or subframe synchronization of the specific cell. It may be configured to be transmitted only to cells, and a set of cells in which information on corresponding floating subframes is shared, including a specific cell, may be defined as a synchronized cell set.

That is, in a heterogeneous network situation in which macro cells and pico cells are common, a network operator may predefine a time synchronization difference or a subframe synchronization difference between pico cells and macro cells located in the communication area of the macro cell. If the network is configured to remain smaller than the specified threshold, the synchronized cell set may be defined as a macro cell and all pico cells located in the communication area of the macro cell.

In addition, the synchronized cell set decodes or tracks each cell in a predefined synchronization signal or reference signal (eg, CRS, CSI-RS) of other adjacent cells. It may be formed by tracking). That is, each cell is one of time synchronization or subframe synchronization between itself and other cells. To derive the difference values for

It may be set to be formed in a distributed form by sharing it between cells (for example, X2 interface). Accordingly, the synchronized cell set may be formed in a distributed manner through cooperation between cells or negotiation between cells, or may be formed in a dynamic form by cooperation / shape between cells.

13 shows a synchronized cell set configured according to the present invention.

Referring to FIG. 13, it is assumed that a heterogeneous network situation in which macro cells and pico cells are common, and macro cells, pico cells #A and pico cells #B are defined as synchronized cell sets. The SIB-based UL-DL configuration configuration of the cell and pico cells is assumed to be UL-DL Configuration # 1.

In the embodiment of FIG. 13, Macro Sal has set SF # (n + 3) and SF # (n + 4) as floating subframes, and corresponding floating subframes (ie, SF # (n +). 3), information on SF # (n + 4)) is informed to neighboring picocells on the synchronized cell set. Thus, pico cells can use the corresponding floating subframes (ie SF # (n + 3), SF # (n + 4)) without any interference due to different communication directions from the macro cell.

In addition, according to the present invention, when an uplink subframe on an SIB is signaled to be designated in the form of ABS (eg, Zero-Power ABS or Nonzero—Power ABS) or MBSFN subframe from a specific cell, such a signal is used. The received neighbor cells may be configured to use the corresponding subframes (ie, uplink subframes on the SIB) for any purpose according to their load conditions. For example, such subframes may be defined as the above-described floating subframes.

In addition, according to the present invention, when an uplink subframe on an SIB is signaled to be designated in the form of ABS (eg, Zero-Power ABS or Nonzero-Power ABS) or MBSFN subframe from a specific cell, such a signal Adjacent cells receiving the received subframes (ie, uplink subframes on the SIB) may be configured to use any purpose according to their load conditions. example For example, such subframes may be defined as the above-described floating subframes.

Alternatively, according to the present invention, subframe sets having different interference characteristics may exist due to different communication directions between cells. In the present invention, first, the type or shape of interference considers the type of interference and classifies a plurality of subframes into a predetermined number of subframe sets. In addition, one or more channel state information (CSI) derivation and reporting operations are set in at least some subframe sets of a predetermined number of subframe sets, or one or more interference estimation operation or channel state information process (CSI Process). ) Can be set.

For example, in a situation where picocells are commonly present in a communication area between the macro cell and the macro cell, only the pico cells perform a dynamic change operation of radio resource usage according to a change in the cell load state, and the macro cell is identified. It may be assumed that the subframes are designated ABS (eg, Zero-Power ABS or Nonzero-Power ABS) and signaled to the pico cells.

In this case, the pico cells may classify a plurality of subframes into two sets of subframes (that is, a predefined number) (ie, Set #A, Set #B), and Set # 八 and Set # 8 may be configured as a subframe set at a location designated by ABS and a subframe set at a location designated as Non-ABS. Furthermore, the above-described subframe classification setting of pico cells may be set based on the presence or absence of interference from the macro cell.

That is, in Set #A, since there is no or little interference from the macro cell due to the ABS setting, and only interferences between picocells exist, the set #A has a plurality of channel state information (CSI). The derivation and reporting operation may be set, or the interference estimation operation or the channel state information process (CSI Process) may be set. For example, in Set #A, interference received from a macro pico cell with low interference and received from a dynamically changing subframe of an adjacent pico cell on a downlink subframe of a serving pico cell or a statically used neighboring pico cell is used. When only interference received on the downlink subframe of the serving pico cell from the subframes is relatively strong, two channel state information (CSI) derivation and reporting operations may be configured in the corresponding Set #A. [165] On the other hand, in Set #B, because of non-ABS setting, interference from macro cell is relatively stronger than interference between pico cells. ) Derivation and reporting operations (black or interference estimation operation or channel state information process (CSI Process)) may be set.

Accordingly, in the present invention, a plurality of channel state information (CSI) derivation and reporting operations are performed only in a specific partial subframe set among a predetermined number of subframe sets, or a plurality of interference estimation operations or channel states. An information process (CSI Process) may be established.

That is, a subframe set in which a plurality of channel state information (CSI) derivation and reporting operations are configured among a predetermined number of subframe sets is used for downlink subframes (eg, Downlink subframes on the SIB) Black may be configured to be limited to downlink subframes (eg, uplink subframes on the SIB) that are changed in use. Of course, downlink subframes for which static interference is used or subframe sets for which a plurality of interference estimation operations or channel state information processes (CSI processes) are set among the predefined number of subframe sets are statically used, or downlink for which the use is changed. It may be set to be limited to subframes.

In addition, in the present invention, when the macro cell sets ABS (eg, Zero-Power ABS or Nonzero-Power ABS) only for downlink subframes statically used by pico cells, A subframe set in which at least one of a plurality of channel state information (CSI) derivation or reporting operations, an interference estimation operation, or a channel state information process (CSI process) is set among the previously defined number of subframe sets. If limited to downlink subframes that are statically used, this may also be defined as being limited to downlink subframes designated by the macro cell as ABS.

In addition, according to the present invention, at least one of a plurality of channel state information (CSI) derivation and reporting operations, an interference estimation operation, or a channel state information process (CSI Process) among a predetermined number of subframe sets is determined. The subframe set to be set is that the macro cell is ABS (eg, Zero-Power ABS or Nonzero-Power ABS). It may be set to be limited to the subframes specified by. Furthermore, the macro cell

Downlink subframes designated by ABS or macro cells may be configured to be limited to subframes or downlink subframes designated by Non-ABS.

Additionally, the above-described settings for the subframe sets may be set by one channel state information (CSI) derivation and reporting operation among a predefined number of subframe sets, or may be interference estimation operation or channel state. It is also applicable to define a set of subframes in which a CSI process is configured.

In addition, according to the present invention, only pico cells perform a dynamic change operation of a radio resource use according to a change in cell load state in a situation in which pico cells are present in a communication between the macro sal and the corresponding macro cell. Independently deriving and reporting channel state information (CSI) or interference estimation even when a cell designates specific subframes (eg, Zero-Power ABS or Nonzero—Power ABS) and signals the information to pico cells Alternatively, at least one of the channel state information process (CSI Process) may be extended.

[172] For example, a Set and a Set #B set based on an interference type or interference type from a macro cell are composed of a subframe set at a position designated as Non-ABS and a subframe set at a position designated as ABS, respectively. Assume Here, in Set #A, since there is interference from uplink communication of the macro cell and interference from downlink communication of the macro cell due to the non—ABS setting, the set #A has a large number in the set #A. At least one of four channel state information (CSI) derivation and reporting operations or an interference estimation operation black or channel state information process (CSI Process) may be set. On the other hand, in Set #B, since there is no or little interference from the macro cell due to the ABS setting, the Set #B has one channel state information (CSI) derivation and reporting operation or interference estimation operation or channel state information process ( CSI Process) may be set to be performed.

In the above-described embodiments of the present invention, "uplink-downlink configuration information on SIBs between cells is set differently", "Non-ideal Backhaul Black or Ideal Backhaul situation", "time synchronization between cells is not correct. If not, "or" in case of transmitting the cooperation-related information through a predefined radio resource channel between cells "can be extended to at least one case. In addition, the above-described embodiments of the present invention may be configured to be limitedly applied only when the dynamic change operation mode for radio resource usage is set.

In addition, embodiments of the present invention can be extended and applied even in a situation in which a radio resource change operation is performed based on a predefined period. In addition, the present invention may be extended to dynamically change radio resources of a specific component carrier (CO) or a specific cell under the condition of carrier aggregation. .

In addition, according to the present invention, the extension is applied even when dynamically configuring and changing the radio resource usage on the extension carrier under the situation of using an extension carrier (extension carrier or a new carrier type) for communication based on a carrier aggregation technique. It is possible.

The above-described embodiments of the present invention can be extended even when the macro cell and the pico cell use the same channel (Co-channel) band or when the adjacent channel (Adjacent Channel) band is used.

In addition, the above-described embodiments of the present invention can be extended even when macro cells and pico cells are common or only pico cells are present. For example, the present invention can be extended and applied even when picocells communicate using a channel band different from a mark cell or a channel band relatively far apart.

The above-described embodiments of the present invention present various methods to which the present invention is applied, and the principles of the method are also included in the proposed methods of the present invention.

[180] Figure 14 illustrates a base station and user equipment that can be applied to an embodiment of the present invention, when a relay is included in a wireless communication system, communication is performed between the base station and the relay in the backhaul link and communication in the access link is relayed This is done between user devices. Therefore, the base station or user equipment illustrated in the figure may be replaced with a relay according to the situation.

Referring to FIG. 14, a wireless communication system includes a base station (BS) 110 and a user equipment (UE) 120. Base station 110 includes a processor 112, a memory 114, and a radio frequency (RF) unit 116. The processor 112 may be configured to implement the procedures and / or methods proposed in the present invention. Memory 114 It is connected to the processor 112 and stores various information related to the operation of the processor 112. The RF unit 116 is connected with the processor 112 and transmits and / or receives a radio signal. The user device 120 includes a processor 122, a memory 124, and an RF unit 126. The processor 122 may be configured to implement the procedures and / or methods proposed in the present invention. The memory 124 is connected with the processor 122 and stores various information related to the operation of the processor 122. The RF unit 126 is connected with the processor 122 and transmits and / or receives a radio signal. Base station 110 and / or user equipment 120 may have a single antenna or multiple antennas.

The embodiments described above are those in which the components and features of the present invention are combined in a predetermined form. Each component or feature is to be considered optional unless stated otherwise. Each component or feature may be embodied in a form that is not combined with other components or features. It is also possible to combine some components and / or features to constitute an embodiment of the invention. The order of the operations described in the embodiments of the present invention may be changed. Some configurations or features of one embodiment may be included in another embodiment or may be replaced with corresponding configurations or features of another embodiment. It is obvious that the embodiments can be constructed by combining claims that do not have an explicit citation in the claims or incorporated into new claims by post-application correction.

The embodiment according to the present invention may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. In the case of a hardware implementation, an embodiment of the present invention may include one or more applicat ion specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), and programmable logic devices (PLDs). ), Programmable programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of implementation by firmware or software, an embodiment of the present invention may be implemented in the form of modules, procedures, functions, etc. that perform the functions or operations described above. Software code may be stored in a memory unit and driven by a processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various known means. It is apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the features of the present invention. The above detailed description, therefore, is not to be construed as limiting in all respects, but should be considered as illustrative. The scope of the present invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

[186] [Industrial Availability]

The method of sharing radio resource information and the apparatus for the same in the wireless communication system as described above have been described with reference to an example applied to the 3GPP LTE system, but it is applicable to various wireless communication systems in addition to the 3GPP LTE system. It is possible.

Claims

[Range of request]

[Claim 1]

A method of sharing radio resource information of a cell in a multi-cell wireless communication system,

Transmitting radio resource information to a neighbor cell; And receiving an acknowledgment message for the radio resource information from the neighbor cell.

The radio resource information is information for changing radio resource usage of a specific radio resource region.

The acknowledgment message is a message indicating whether the radio resource usage change is allowed in the neighbor cell.

Wireless resource information sharing method.

[Claim 2]

The method of claim 1,

The confirmation message is

Characterized in that determined in the neighboring cell based on at least one of an uplink-downlink communication load state of the neighboring cell and a predicted interference amount on the specific radio resource region.

Wireless resource information sharing method.

[Claim 3]

The method of claim 1,

The confirmation message is

Characterized in that the transmission is based on a predefined physical wireless channel or X2 interface,

How to share radio resource information.

[Claim 4]

The method of claim 1,

The specific radio resource region is,

The neighboring cell is configured not to perform uplink-downlink communication; Wireless resource information sharing method.

[Claim 5]

The method of claim 1

The confirmation message indicates that the radio resource usage change is not permitted on the specific radio resource region.

Receiving recommended radio resource usage change information from the neighbor cell;

Wireless resource information sharing method.

[Claim 6]

The method of claim 1,

The radio resource information includes at least one candidate uplink-downlink configuration.

Contains information about the UL-DL configuration,

The acknowledgment message includes information on a specific uplink-downlink configuration allowed in the neighbor cell among the at least one candidate uplink-downlink configuration.

Wireless resource information sharing method.

[Claim 7]

The method of claim 1,

The adjacent cell is,

Characterized in that the time synchronization difference between the cell and the cell (cell) less than a predetermined threshold,

Wireless resource information sharing method.

[Claim 8]

The method of claim 1,

The radio resource information is

Characterized in that it comprises information on the number of subframes in which the use of the radio resource is changed.

How to share radio resource information.

[Claim 9]

The method of claim 1, The specific radio resource region is,

Characterized in that it comprises a radio resource for transmitting and receiving a specific reference signal,

Wireless resource information sharing method.

[Claim 10]

The method of claim 9,

The specific reference signal is,

It is set according to the predefined reference signal setting information.

The reference signal configuration information includes at least one or more of the number of antenna ports, physical cell identifiers, virtual cell identifiers, types of reference signals, configuration indexes, and transmit power of reference signals.

Wireless resource information sharing method.

[Claim 111]

The method of claim 1

The radio resource information,

At least one of a subframe at a specific time point and a use for the subframe at a specific time point,

Wireless resource information sharing method.

[Claim 12]

Clause 11

The radio resource information,

Further comprising information about an uplink control channel transmission region or a specific reference signal transmission region of the serving cell.

Wireless resource information sharing method.

[Claim 13]

The method of claim 1,

The radio resource usage change is,

Characterized in that the use of the radio resources configured for uplink communication for the downlink communication, or to use the radio resources configured for downlink communication for the uplink communication, Wireless resource information sharing method.

[Claim 14]

The method of claim 1,

The radio resource information is,

And further comprising information about resource usage of the specific radio resource region.

Wireless resource information sharing method.

[Claim 15]

In the method of sharing radio resource information in a multi-cell wireless communication system,

Receiving radio resource information from a specific cell;

Determining whether to allow a change in radio resource usage of the specific cell based on the radio resource information and an uplink-downlink communication load state; And

"— Sending an acknowledgment message to the specific cell indicative of whether to allow the change of radio resource usage;

The radio resource information, characterized in that the specific cell is information for changing the radio resource usage of a specific radio resource region,

Wireless resource information sharing method.