JP5698225B2 - Signal transmission method using non-communication space and apparatus therefor - Google Patents

Description

  The present invention relates to a signal transmission method, and more particularly to a signal transmission method and apparatus for improving throughput in a heterogeneous network or a multi-input multi-output system.

  Wireless communication systems are widely deployed to provide various communication services such as voice or data. Generally, a wireless communication system is a multiple access system that can provide communication with multiple users by sharing available system resources (bandwidth, transmission power, etc.). Examples of multiple access systems include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, time division multiple access (TDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single carrier frequency division There are multiple access (SC-FDMA) systems, multi-carrier frequency division multiple access (MC-FDMA) systems, and the like. In a wireless communication system, a terminal can receive information from a base station via a downlink (DL) and can transmit information to the base station via an uplink (UL). The information transmitted or received by the terminal includes data and various control information, and various physical channels exist depending on the type and use of information transmitted or received by the terminal.

  An object of the present invention is to provide a method and apparatus for transmitting signals in a heterogeneous network so as to minimize the influence of inter-cell interference.

  Another object of the present invention is to provide spatial silencing on the same carrier shared by a plurality of cells so as to minimize the influence of interference between the cells in a wireless communication system.

  The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned can be considered as normal problems in the technical field to which the present invention belongs. It will be clearly understood by those who have knowledge.

  A method of transmitting a signal in a heterogeneous network according to an embodiment of the present invention for solving the above-described problem is a step of determining a weight vector for forming a beam pattern to be applied to a subcarrier by a base station. And transmitting carrier operation information including information on the determined weight vector via a primary carrier, and transmitting an auxiliary carrier by applying the determined weight vector.

  Here, the auxiliary carrier and the primary carrier may be a carrier transmitted via a separate frequency partition among a plurality of frequency partitions constituting an available system band.

  The step of determining a weight vector for forming a beam pattern to be applied to a supplementary carrier by a base station according to an embodiment of the present invention includes determining a carrier used by a macro cell provided by the base station and a small cell included in the macro cell. You may selectively perform when it overlaps.

  The step of determining a weight vector for forming a beam pattern to be applied to an auxiliary carrier by a base station according to an embodiment of the present invention relates to a set of weight vectors including one or more available weight vectors applicable to the auxiliary carrier. Transmitting information to a plurality of terminals via a primary carrier, receiving feedback information from the plurality of terminals, and determining a weight vector specified for each terminal from a weight vector set based on the feedback information And may be included.

  A signal transmission method according to an embodiment of the present invention includes a step of receiving feedback information including interference information between a plurality of cells based on channel measurement from a plurality of terminals, and a macro cell in which a base station provides a service based on the interference information. And adjusting a region in which a beamformed auxiliary carrier wave is transmitted.

  A signal transmission method according to an embodiment of the present invention relates to a step in which a base station determines a weight vector for forming a beam forming applied to a reference signal (Reference Signal), and an order of the beam forming applied to the reference signal. The method may further include a step of transmitting reference signal operation information including at least one of information and antenna number information, and a step of transmitting a reference signal subjected to beam forming.

  Meanwhile, the step of determining a weight vector for forming a beamforming applied to a reference signal according to an embodiment of the present invention may include a cell common reference according to each of a plurality of frequency partitions constituting an available system band. It may be decided to apply a separate weight vector to the signal.

  On the other hand, when a terminal measures a carrier wave to which beam forming is applied, information on a form in which the corresponding carrier wave is transmitted to the terminal can be distributed to the base station, and the information is time (subframe / frame transmission unit), Information about resources such as frequency (subcarrier, subcarrier group or carrier or carrier group), or space (such as spatial layer) or code (such as spreading sequence or orthogonal resource) may be included. Such information may be transmitted as an auxiliary index for channel measurement when the terminal reports a measurement value by carrier wave measurement, or may be transmitted as a result of pure channel measurement.

  A signal transmission method according to an embodiment of the present invention provides information on auxiliary carrier transmission including information on a weight vector for forming beamforming applied to the auxiliary carrier and information on time / frequency resources to which the beamforming weight value is applied. And a step of receiving feedback information including a channel measurement result using the auxiliary carrier from the terminal, and a step of performing carrier aggregation on the auxiliary carrier using the feedback information. .

  A method for receiving a signal in a heterogeneous network according to another embodiment of the present invention for solving the above-described problem is a method for receiving weight signals determined for forming a beam pattern to be applied to an auxiliary carrier from a base station. Receiving the carrier operation information including the primary carrier (primary carrier) and receiving the auxiliary carrier to which the weight vector is applied from the base station.

  A signal reception method according to an embodiment of the present invention includes receiving, via a primary carrier, information about a set of weight vectors including one or more available weight vectors applicable to an auxiliary carrier from a base station; Receiving a downlink signal to which each weight vector included in the weight vector set is applied from the station, and transmitting feedback information based on channel measurement results on the downlink signal to the base station. Good.

  Here, it is preferable that the weight vector applied to the auxiliary carrier wave is determined based on feedback information.

  A signal reception method according to an embodiment of the present invention includes a step of performing channel measurement using a downlink signal received from a base station, and transmitting feedback information including interference information between a plurality of cells by channel measurement to the base station. And a step.

  A signal reception method according to an embodiment of the present invention is a method of transmitting an auxiliary carrier from a base station including information about a weight vector for forming beamforming applied to the auxiliary carrier and time / frequency resources to which the beamforming weight value is applied. Receiving information on the base station, transmitting feedback information including a channel measurement result using the auxiliary carrier to the base station, and receiving an auxiliary carrier that has been subjected to carrier aggregation based on the feedback information. May be included.

  Here, the auxiliary carrier and the primary carrier may be a carrier transmitted via a separate frequency partition among a plurality of frequency partitions constituting an available system band.

  In a heterogeneous network according to another embodiment of the present invention for solving the above-mentioned problem, a base station uses a transmission module for transmitting a radio signal, a reception module for receiving a radio signal, and an auxiliary carrier transmitted through the transmission module. A processor for determining a weight vector for forming a beam pattern to be applied, and the processor transmits, through the transmission module, carrier operation information including information on the determined weight vector to the terminal through the primary carrier. The auxiliary carrier may be transmitted to the terminal by transmitting and applying the determined weight vector via the transmission module.

  In a heterogeneous network according to another embodiment of the present invention for solving the above-mentioned problem, a terminal receives a radio signal reception module, a radio signal transmission module, and a downlink signal received via the reception module. A processor for performing channel measurements based on the carrier operation information including information on weight vectors determined for forming a beam pattern to be applied to the auxiliary carrier from the base station via the receiving module, And an auxiliary carrier wave to which a weight vector is applied may be received.

  A processor according to an embodiment of the present invention receives information about a set of weight vectors including one or more available weight vectors applicable to an auxiliary carrier from a base station via a receiving module via a primary carrier, When receiving a downlink signal to which each weight vector included in the vector set is applied, channel measurement is performed on the downlink signal to which each weight vector is applied, and feedback information based on the channel measurement result is generated and transmitted. You may comprise so that it may transmit to a base station via a module.

  A processor according to an embodiment of the present invention includes, via a receiving module, information on time / frequency resources to which a beam forming weight value and a beam forming weight value are applied to form a beam forming applied from a base station to an auxiliary carrier. When receiving information related to auxiliary carrier transmission, feedback information including a channel measurement result using the auxiliary carrier may be generated and transmitted to the base station via the transmission module.

  Here, the feedback information may include interference information between a plurality of cells by channel measurement.

  In a heterogeneous network according to another embodiment of the present invention for solving the above problems, a base station includes a transmission module for transmitting a radio signal, a reception module for receiving a radio signal, and a transmission module. A processor for determining a weight vector for forming a beam pattern to be applied to an auxiliary carrier to be transmitted, and the processor receives, via the transmission module, carrier operation information including information on the determined weight vector as a primary carrier. The auxiliary carrier wave may be transmitted to the terminal by applying the determined weight vector to the terminal via the transmission module.

  Here, when the carrier used by the macro cell provided by the base station and the small cell included in the macro cell overlap, the processor can determine a weight vector for forming a beam pattern to be applied to the auxiliary carrier.

  A processor according to an embodiment of the present invention is configured to generate information about a set of weight vectors including one or more available weight vectors applicable to an auxiliary carrier and transmit the information to a terminal via a transmission module; Based on the feedback information received from the terminal via the receiving module, the weight vector specified for the terminal can be determined from the weight vector set.

  A processor according to an embodiment of the present invention performs beam forming in a macro cell provided with a service by a base station based on feedback information including interference information between a plurality of cells based on channel measurement from a terminal received via a receiving module. The area in which the performed auxiliary carrier wave is transmitted may be adjusted.

  The processor determines a weight vector for forming a beamforming to be applied to the reference signal, and generates reference signal operation information including at least one of information on a beamforming order to be applied to the reference signal and antenna number information. Then, it may be configured to transmit to the terminal via the transmission module.

  The processor generates information on auxiliary carrier transmission including information on time / frequency resources to which the beamforming weight value and beamforming weight value applied to form the beamforming applied to the auxiliary carrier are applied, and transmits the terminal via the transmission module. The subcarrier may be aggregated with respect to the auxiliary carrier by using feedback information based on the auxiliary carrier measurement received from the terminal via the receiving module.

  The above embodiments are only a part of preferred embodiments of the present invention, and various embodiments reflecting the technical features of the present invention will be described below for those who have ordinary knowledge in the art. Will be derived and understood from the detailed description of the invention described below.

  According to the above-described embodiment of the present invention, the base station can control the carrier specific area where the influence of interference on adjacent cells can be reduced by using spatial non-communication.

  The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned are the normal ones in the technical field to which the present invention belongs from the following description. It will be clear to those who have knowledge.

The accompanying drawings, which are included as part of the detailed description to assist in understanding the present invention, provide examples of the present invention and together with the detailed description explain the technical idea of the present invention.
It is a figure which shows the network structure of an evolution general purpose mobile communication system (E-UMTS). FIG. 2 is a diagram illustrating a structure of a radio frame used in a long-term evolution (LTE) system. It is a figure which shows the physical channel and signal transmission using the same in a LTE system. It is a block diagram which shows the radio | wireless communications system to which the femtocell base station was added. 5 is a flowchart illustrating an example of a signal transmission procedure for mitigating inter-cell interference in a heterogeneous network system according to an embodiment of the present invention. It is a figure which shows an example of the signal transmission procedure by one Example of this invention. It is a figure which shows the other example of the signal transmission procedure by one Example of this invention. FIG. 5 is a diagram illustrating a resource frequency-time domain for transmitting a carrier according to an embodiment of the present invention. It is a block block diagram for demonstrating the base station and terminal which can implement the Example of this invention.

  The structure, operation and other features of the present invention will be readily understood from the embodiments of the present invention described with reference to the accompanying drawings. The embodiments of the present invention can be applied to various wireless connection technologies such as CDMA, FDMA, TDMA, OFDMA, SC-FDMA, and MC-FDMA. CDMA may be a radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA may be a radio technology such as Global System for Mobile Communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rate (EDGE) for GSM evolution. OFDMA may be a wireless technology such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, E-UTRA, and the like. UTRA is part of UMTS. Third Generation Partnership Project (3GPP) LTE is part of E-UMTS that uses E-UTRA. Advanced LTE (LTE-A) is an evolved version of 3GPP LTE.

  The following embodiments will be described with a focus on the case where the technical features of the present invention are applied to a 3GPP system, but this is an example and the present invention is not limited thereto.

  In the present invention, the description is based on LTE-A. However, the proposed concept, proposed scheme, and embodiments of the present invention are not particularly limited, and other systems using multiple carriers (eg, IEEE 802). .16m system).

  FIG. 1 is a diagram illustrating a network structure of E-UMTS. E-UMTS is also called an LTE system. Communication networks are widely deployed and provide various communication services such as voice and packet data.

  Referring to FIG. 1, the E-UMTS network includes an E-UTRAN, an evolved packet core network (EPC), and a terminal (UE). The E-UTRAN includes one or more base stations (eNode B: eNB) 11 and can arrange one or more terminals 10 in one cell. A mobility management entity / system structure evolution (MME / SAE) gateway 12 may be provided at the network end to connect to an external network. The downlink refers to communication from the base station 11 to the terminal 10, and the uplink refers to communication from the terminal to the base station.

  The terminal 10 is a communication device carried by the user, and the base station 11 is generally a fixed station that communicates with the terminal 10. The base station 11 provides the terminal points of the user plane and the control plane to the terminal 10. One base station 11 may be arranged for each cell. An interface for transmitting user information or control information may be used between the base stations 11. The MME / SAE gateway 12 provides the terminal 10 with the endpoint of the session and mobility management function. The base station 11 and the MME / SAE gateway 12 may be connected via an S1 interface.

  MME provides various functions including delivery of radio paging messages to base station 11, security control, standby mobility control, SAE bearer control, and encryption and integrity protection of non-connection layer (NAS) signal notifications To do. The SAE gateway host provides various functions including user plane switching for terminating the plain packet and supporting the mobility of the terminal 10. In this specification, the MME / SAE gateway 12 is abbreviated as a gateway, and includes both the MME gateway and the SAE gateway.

  A plurality of nodes can be connected between the base station 11 and the gateway 12 via the S1 interface. Base stations 11 are interconnected via an X2 interface, and adjacent base stations can have a network network structure with an X2 interface. FIG. 2 illustrates the structure of a radio frame used in LTE.

Referring to FIG. 2, a radio frame has a length of 10 ms (327200 * T _s ) and includes 10 equally sized subframes. Each subframe has a length of 1 ms and includes two 0.5 ms slots. T _s represents a sampling time and is represented by T _s = 1 / (15 kHz * 2048) = 3.2552 * 0 ⁻⁸ (about 33 ns). A slot includes a plurality of OFDM (or SC-FDMA) symbols in the time domain, and includes a plurality of resource blocks (RBs) in the frequency domain. In the LTE system, one resource block includes 12 secondary carriers * 7 (6) OFDM (or SC-FDMA) symbols. Frame structure type-1 and frame structure type-2 are used for FDD and TDD, respectively. Frame structure type-2 includes two half-frames, and each half-frame includes, in addition to five subframes, a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS). )including. The structure of the radio frame described above is merely an example, and the number / length of subframes, slots, or OFDM (or SC-FDMA) symbols can be variously changed.

  FIG. 3 illustrates a physical channel and signal transmission using the physical channel in the LTE system.

  When the power is turned on or a new cell is entered, the terminal performs an initial cell search operation such as synchronizing with the base station (S301). For this purpose, the terminal receives a primary synchronization channel (P-SCH) and a secondary synchronization channel (S-SCH) from the base station, and synchronizes with the base station to obtain cell identification information (ID). Information such as can be acquired. Thereafter, the terminal can receive the physical broadcast channel from the base station and acquire the broadcast information in the cell. The terminal that has completed the initial cell search obtains more specific system information by receiving the physical downlink shared channel (PDSCH) based on the physical downlink control channel (PDCCH) and information carried by the PDCCH. Yes (S302).

  On the other hand, if the terminal is first connected to the base station or there is no radio resource for signal transmission, the terminal can connect to the base station by a random access procedure (RACH) (steps S303 to S306). Therefore, the terminal can transmit a specific sequence as a preamble via the physical random access channel (PRACH) (S303 and S305), and can receive a response message for the preamble via the PDCCH and the corresponding PDSCH (S304 and S305). S306). In case of contention based RACH, the collision resolution procedure can be further executed.

  The terminal that has performed the procedure as described above can subsequently perform PDCCH / PDSCH reception (S307) and PUSCH / PUCCH transmission (S308) as a general-purpose uplink / downlink signal transmission procedure.

  The control information transmitted from the terminal to the base station via the uplink or received from the base station by the terminal includes a downlink / uplink acknowledgment (ACK) / negative acknowledgment (NACK) signal, a schedule request (SR) Information, channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI) and the like. In the case of the 3GPP LTE system, the terminal can transmit control information such as the above-described CQI / PMI / RI via PUSCH and / or PUCCH.

  A heterogeneous network may be configured, and a plurality of small cells may exist in one cell. In the following, the macro cell and femto cell will be described.

  FIG. 4 is a configuration diagram of a wireless communication system to which a femtocell base station is added.

  A heterogeneous network is configured, and a small cell such as a femto cell may exist in one macro cell region. The femtocell is an area where a femtocell base station provides a service. A femtocell base station is a small version of a macrocell base station that provides services within the macrocell. In particular, the femtocell base station can perform most of the functions of the macro base station, and may be provided in an area covered by the macro base station or in a shaded area that cannot be covered by the macro base station. The femtocell base stations have a network configuration that operates independently, and can be installed more significantly than relay base stations installed in the city center or indoors. For this reason, the femtocell base station list has too much information and is not included in the adjacent base station list transmitted from the base station to the terminal.

  As shown in FIG. 4, a radio communication system to which a femtocell base station is added includes a femtocell base station 410, a macro base station 420, a femto network gateway (hereinafter referred to as “FNG”) 430, a connection service network (hereinafter referred to as “FNG”). ASN ”) 440 and a connectivity service network (hereinafter“ CSN ”) 450. The macro base station 420 means a general base station of a conventional wireless communication system.

  The femtocell base station 410 is a small version of the macro base station 420 and performs most of the functions of the macro base station. The femtocell base station 410 is directly connected to a TCP / IP network and operates independently like the macro base station 420. The coverage is about 0.1 to 30 m and can be accommodated by one femtocell base station 410. There are about 10 to 20 terminals. The femtocell base station 410 may use the same frequency as the macro base station 420 or may use a different frequency.

  The femtocell base station 410 is connected to the macro base station 420 via the R1 interface, can receive the downlink channel of the macro base station 420, and can transmit a control signal to the macro base station 420. The femtocell base station 410 can cover indoor or shaded areas that cannot be covered by the macro base station 420 and can provide high-speed data transmission. The femtocell base station 410 may be provided in the form of an overlay in the macro cell, or may be provided in a non-overlay form in an area not covered by the macro base station 420.

  In a conventional heterogeneous network or MIMO system, transmission is performed in a macro cell in order to reduce the influence of interference between a small cell such as a femto cell located in the macro cell and the macro cell, and to improve the link quality for a service providing terminal. A carrier on / off method for adjusting the carrier to be used was used.

  In order to reduce the influence of interference on a small cell such as a femto cell in a macro cell, when the same carrier as that of a small cell located in the macro cell is used in the macro cell, transmission of the corresponding carrier can be stopped. In this way, in the small cell region, it is possible to efficiently satisfy high throughput for the carrier corresponding to the carrier stopped in the macro cell. In addition, when carrier on / off is applied to a terminal located at the end of a small cell, interference effects from not only adjacent small cells but also cells of various sizes including the entire cell area are affected. Can be relaxed.

  On the other hand, for a carrier shared by a plurality of cells, a soft fractional frequency reuse system in which control related to power allocation is performed may be used. For example, the influence of interference can be mitigated among a plurality of cells using the same carrier wave by reducing the transmission power level in a cell having high interference with other cells. In this case, by effectively reducing the size of the shared carrier cell, a cell can utilize the carrier corresponding to the managed interference level.

  However, when the conventional carrier on / off method is used in a large cell area including a plurality of terminals such as a macro cell, the carrier on / off operation for a specific terminal is applied to other terminals, and throughput efficiency is improved. The effect is reduced on the side. Specifically, when a turn-off operation is performed on a carrier shared by a plurality of cells, the carrier cannot be used for an intra-cell terminal located inside the cell.

  In addition, since the carrier wave itself can operate in a heterogeneous mode in the heterogeneous network operation, each carrier wave can play a specific role, but when using the carrier on / off method, it is necessary to use various functions that the specific carrier wave can perform. It becomes difficult.

  The present invention proposes a signal transmission method in which the same carrier wave can be used not only in a macro cell but also in a small cell located in the macro cell while mitigating the influence of inter-cell interference.

  Spatial silencing according to an embodiment of the present invention mitigates the influence of inter-cell interference by beam adjustment suitable for multiple cells using the same carrier in one cell, and improves throughput efficiency. It is a method for enhancing.

  Hereinafter, in order to describe a signal transmission method according to an embodiment of the present invention, in the embodiment of the present invention, beam forming is used for a channel shared in a cell region of a MIMO system or a heterogeneous network. Assume that In this case, it is not necessary to use beam forming for small cells arranged in one cell.

  FIG. 5 is a flowchart illustrating an example of a signal transmission procedure for mitigating inter-cell interference in a heterogeneous network system according to an embodiment of the present invention.

  Referring to FIG. 5, a macro base station providing a macro cell including a plurality of small cells such as femtocells may reduce interference effects on small cells such as femtocells sharing the same carrier in the macrocell. A carrier wave can be transmitted using spatial non-communication according to an embodiment of the present invention. As an example of the non-communication of space, beam forming can be used so that signals are transmitted to the remaining areas excluding the small cell area during carrier wave transmission, and the beam forming operation method to be used can be determined (S501). That is, when the base station of the macro cell uses the same carrier as that used in the small cell, beam forming can be applied so that the carrier is transmitted to the remaining area other than the small cell area.

  When transmitting the same carrier wave used in multiple cells, the beam forming operation method for the carrier wave is a form having a specific pattern in a predetermined cycle according to 1) and 2) described below. Alternatively, it is possible to use a system in which a beam is randomly formed and transmitted. Here, the auxiliary carrier is an arbitrary carrier that plays an auxiliary role in transmission / reception of main user information in the system, and may be used in the same meaning as the secondary carrier. The auxiliary carrier can be distinguished from the primary carrier by frequency division.

  When the system band is divided into a plurality of sub-bands, it is possible to selectively and independently disable communication (beam formation) using each sub-band. For example, when a plurality of divided subbands are applied to a carrier on a carrier basis, the primary carrier can be transmitted via the primary subband and the auxiliary carrier can be transmitted via the secondary subband. When the system provides carrier aggregation, each subband corresponds to a component carrier.

  In this specification, the primary carrier and the secondary carrier are terms arbitrarily defined to help understanding of the invention, and may be replaced by other equivalent terms. For example, when providing one continuous frequency block as in an LTE system, the primary carrier and the secondary carrier are divided into subbands (eg, one or more continuous / discontinuous secondary blocks). (Carrier wave). In addition, when the system provides carrier aggregation, the primary carrier and the secondary carrier may be defined in component carrier units, or may correspond to subbands divided in one component carrier.

  Next, the base station that has determined the beamforming operation method for the carrier wave can make adjustments on a cell-by-cell basis in order to eliminate spatial communication (S502). Inter-cell adjustment will be briefly described in the following 3).

  The base station that has performed the beam forming operation method and the inter-cell adjustment can transmit the auxiliary carrier wave through a partial region in the entire frequency bandwidth (S503). In this case, a certain region in which the auxiliary carrier is transmitted in the frequency bandwidth is defined as a subband, and can be distinguished from the primary band that is the region in which the primary carrier is transmitted. The beam forming band corresponds to the above-described subband, and the non-beamforming band corresponds to the above-described primary band. This will be briefly described in the following 4) and 5).

  Thereafter, the base station can receive feedback information regarding channel information measured based on the reference signal (RS) from the terminal (S504). At this time, the base station can transmit the RS by applying the beam forming to the RS, and can notify the additional information in advance so that the terminal located in the cell can receive the beam-formed RS. The procedure for the terminal to receive the RS and perform measurement will be briefly described in the following 6) and 7).

  The base station receiving the feedback information from the terminal can perform control and scheduling for the data channel on the channel for transmitting the auxiliary carrier (S505). This will be briefly described in the following 8).

  Hereinafter, the operation of the base station or terminal corresponding to each stage in the signal transmission procedure according to the embodiment of the present invention will be briefly described.

1) Carrier beam forming

  According to one embodiment of the present invention, in a beam forming system that is used when transmitting a carrier wave, beam forming can be operated only on an auxiliary carrier wave except for the primary carrier wave. For example, all channels transferred over the auxiliary carrier can form one or more beams to minimize the effect of signal interference on adjacent cells.

  FIG. 6 is a diagram illustrating an example of a signal transmission procedure according to an embodiment of the present invention.

  Referring to FIG. 6, the base station can determine one of various beamforming operation methods for the auxiliary carrier (S601). As one of the beam forming operation methods, the beam forming priority order may be defined separately depending on the channel type transmitted through the auxiliary carrier wave.

  As an example, when it is necessary to distinguish transmission channel characteristics by receiving channel measurement / quality of service (QoS) / user information or control information, multiple transmission channels are transmitted according to the importance of QoS, user information or control information. Different weight vectors according to the beamforming priority can be applied to each transmission antenna. As another example, when it is not necessary to distinguish each channel in terms of channel characteristics, single / multiple weights for the same beam pattern adjustment for multiple transmit antennas transmitting via an auxiliary carrier Vector can be applied.

  In this case, when the beam forming operation method is determined so that each channel is distinguished and an independent weight vector is determined for each transmission antenna, the base station can obtain information on the weight vector applied to each antenna to a plurality of terminals, that is, each The beam pattern information related to the terminal or the terminal group can be notified (S602). Alternatively, as the beam pattern information, the information on the weight vector is a vector that becomes a representative value of a certain weight value group among various weight values that are distinguished from each other, information on a weight vector that can be distinguished by a terminal, or information on a partition unit. Can be included.

  Each terminal that has received the information regarding the beam pattern can receive the downlink signals transmitted through the various transmission channels based on the beam pattern information (S603).

  Meanwhile, the base station according to an embodiment of the present invention may change and adjust the beam forming pattern according to a certain rule so that the auxiliary carrier to which the beam forming is applied is transmitted over the entire cell region.

2) Random beam formation or periodic beam formation

  When a beam pattern for an auxiliary carrier wave is formed according to an embodiment of the present invention, the formed beam pattern direction may not cover all cell regions. In this case, it is possible to set various weight vectors that can cover all areas that require signal transmission in one cell, but the efficiency decreases when the number of transmitting antennas is not sufficient. That is, if the number of transmitting antennas is not sufficient, the beam pattern form becomes too wide and may cause unwanted interference to other cells. In order to avoid this, it is necessary to configure a plurality of beams. For this purpose, a very large number of antennas are required, or beams that are distinguished on time / frequency / code resources need to be formed.

  Therefore, in a base station having a small number of antennas, beams may be generated with a time difference so that each beam can cover a specific service area. In this case, multiple beams are not used at the same time. Can be used in part by frequency. For example, according to an embodiment of the present invention, the beam pattern direction can be changed according to a predetermined rule that has already been set for the auxiliary carrier, for example, a rule related to beam position rotation or beam designation. . The multiple beam application can use beam forming by a time domain division (TDD) method or a frequency domain division (FDD) method, so that the beam direction can be changed every certain time (eg, subframe) on the transmission side. In the TDD scheme, the base station can be configured to configure the beam pattern so that the beam is transmitted to other regions in the cell according to time, or not to transmit the beam to the small cell region existing in the macro cell. Alternatively, when the FDD scheme is used, the beam pattern direction transmitted by the base station can be changed by a frequency subset (eg, subband beam forming).

  Alternatively, when a plurality of macro cells use the same carrier wave, the beam pattern specified for each macro cell can be changed or exchanged at a constant period in order to reduce the influence of inter-macro cell interference. For example, it is possible to determine the beam direction by applying an independent offset to other macro cells using the same carrier while sequentially exchanging the positions of the beams in any one of the reference macro cells. As another example, the beam direction may be selected according to a specific pattern (for example, a predetermined period of 10 ms) for each cell.

  In the embodiment of the present invention, when the beam direction is changed while performing the beam forming at the base station when transmitting the carrier wave, information regarding the changed beam pattern may be transmitted to the terminal.

  The beam operation as described above can be used for the base station to receive a report on channel measurement information from the terminal at regular intervals. In other words, instead of always operating the beam, when the information about channel measurement is received from the terminal, the act of exchanging the position of the beam as described above is performed according to time, and at other times it is performed to a specific terminal. It may be operated using a beam specific to the terminal to provide the service.

  FIG. 7 is a diagram illustrating another example of a signal transmission procedure according to an embodiment of the present invention.

  Referring to FIG. 7, the base station broadcasts to a plurality of terminals carrier information including information on a set of weight vectors including one or more weight vectors applicable to each transmission antenna as information on the carrier operation method ( S701). In contrast to this, the carrier operation information including information on the weight vector set may be already set in the base station and / or the terminal.

  Prior to determining the beamforming method to be used for the auxiliary carrier, the base station uses the upper layer or L1 / L2 signal notification via the primary carrier that can reach the entire cell area, and the weight vector that can be used for beamforming. Carrier operation information including information on aggregates can be broadcast. Then, it is possible to determine how to implement beam forming for the auxiliary carrier wave by receiving feedback information for this.

  Each terminal that has received the carrier operation information can receive downlink signals transmitted through various transmission channels based on the beam pattern information included in the terminal (S702).

  Then, the terminal can measure the channel state based on the carrier wave transmitted using each weight vector, and can transmit feedback information based on the measurement result to the base station (S703). The feedback information includes, in addition to channel quality information (CQI) and precoding matrix index (PMI), information related to a weight vector that satisfies the optimum reception state of the corresponding terminal or a weight vector that can be read by the corresponding terminal. It is also possible to include time information such as subframes / frames that can be used to infer, information on frequency bands, information on used resources, and the like.

  The base station that has received the feedback information can determine a carrier operation method for determining specific weight vector information for the corresponding terminal from the weight vector set based on the feedback information (S704). Specifically, the base station determines a beam pattern suitable for transmitting a signal to the corresponding terminal based on the feedback information, and determines how to use the beam pattern for the corresponding terminal. it can. That is, the weight vector can be determined so that the corresponding terminal transmits a beam pattern to a region located in the cell.

  Then, the beamforming operation information determined for the corresponding terminal is unicasted to the terminal (S705), and an auxiliary carrier can be transmitted using the determined beamforming method (S706).

  That is, according to an embodiment of the present invention, the carrier operation information broadcast by the base station to all terminals located in the cell through the primary carrier is the same, but after receiving the feedback information, The beam pattern information to be transmitted can be distinguished for each terminal, and can vary depending on the position of the terminal and / or the service area.

  Here, the feedback information transmitted from the terminal to the base station can be obtained by measurement on an auxiliary carrier assuming (semi) random beam forming. The terminal can perform the measurement for the specific beam based on the beam forming configuration (time / frequency subband / beam weight vector) information indicated by the base station. The measurement result for a specific beam can be reported as to whether or not the configuration of the corresponding beam is compatible with the terminal by simply using an on / off method or an indicator composed of one bit. In this case, the base station can select statistical information and partial cell coverage information for effectively using the beamforming weight values that are often available using such on / off information.

3) Communication between cells or base stations for auxiliary carrier operation

  While performing beam forming on an auxiliary carrier according to an embodiment of the present invention, the base station must perform cell adjustment (or adjustment of a service area reached by beam forming) to minimize the influence of inter-cell interference. . For this reason, in order to define a service area where beam forming (or a weight vector uniformly defined for beam forming) reaches, first, interference information must be shared between cells participating in communication.

  For small cells, beamforming may or may not be used for the auxiliary carrier, but interference information must be obtained from neighboring cells for the auxiliary or primary carrier. When the terminal uses the carrier wave to measure the interference and / or beam direction, the channel measurement result or PMI information can be reported to the serving cell. Alternatively, channel measurement is performed on the uplink signal transmitted from the terminal internally in the base station of the service providing cell, and inter-cell interference information can be acquired. The channel measurement may be performed based on the cell-specific reference signal transmitted via each subframe without separately performing precoding, or based on the precoded RS.

  On the other hand, when an auxiliary carrier is used for interference measurement, it is determined from a beam set that can be defined as a frequency band or subframe by beamforming configuration information (period, subband, weight vector, etc.) specified by the base station based on channel measurement information. Any one beam set can be determined.

  Of the channel measurement information, non-acceptable beamforming needs to be reported to the corresponding transmission cell. At this time, when a plurality of channel measurements are reported, information on corresponding measurement settings such as subband information, subframe information, or radio frame information needs to be reported at the same time.

4) Auxiliary carrier setting

  According to another embodiment of the present invention, when a macro cell and a small cell use the same carrier wave, a spatial carrier communication method is not used, and a carrier wave specified for a cell or a cell group or a specific carrier wave for a network is used. An auxiliary carrier wave can be configured. As a result, the UE does not need to perform channel measurement on the remaining auxiliary carriers other than the auxiliary carrier specified by itself during handover or initial cell connection.

  In a heterogeneous network system, there are a plurality of small cells that can use an available carrier wave for a system used in a macro cell. However, the carrier wave transmitted in the small cell may be affected by the position of the small cell and the operation method of the macro cell. Therefore, setting of an auxiliary carrier shared by cells may be performed by negotiation between related cells such as a small cell and an adjacent macro cell. After the negotiation step for the auxiliary carrier, the small cells can report interference or channel quality / status information on the shared auxiliary carrier to the macro cell, and the macro cell receiving the same can implement beam forming that minimizes the interference effect.

5) Segmented operation

  The LTE-A system can provide the LTE band and the carrier constituting the LTE-A band, so that the LTE band can be used in the legacy mode and the compatible mode, and the LTE-A band is an additional LTE. -A Can be used for optimization. Such carrier types can be distinguished on the frequency-time domain, as shown in FIG.

  FIG. 8 is a diagram illustrating a resource frequency-time domain for transmitting a carrier according to an embodiment of the present invention.

  Referring to FIG. 8, the fixed region on the frequency domain is a non-beamforming band or subband 801 used for transmitting signals to all terminals located in the cell, and can be used for primary carrier transmission. . This can be distinguished from a beam forming band or a primary band 802, which is a sub band that can be used to transmit an auxiliary carrier to which beam forming is applied to a specific terminal according to an embodiment of the present invention.

  In such a structure, spatial non-communication according to an embodiment of the present invention can be defined differently from conventional non-carrier communication. For example, the conventional non-communication of the carrier wave is limited to a partial subband of the LTE-A band or a partial band of the LTE band, and uses carrier transmission on / off within the limited band. As a result, the small cell can use the subband that has been made non-communication as a carrier wave during operation. That is, the generated carrier center is not assigned to the carrier center of the macrocell carrier. However, a small cell can meet a low interference level without being affected by interference in a decommunication subband from cooperating neighboring cells.

  The non-communication subband may be set more flexibly. The partial bandwidth or the total bandwidth may be spatially decommissioned while the non-communication subband is still being used to provide services to terminals throughout the cell area. The non-communication subband can assist the operation of the non-communication subband.

  When using spatial de-communication according to one embodiment of the present invention, the beamforming weight vector should be provided only to the targeted de-communication subband. As shown in FIG. 8, the weight vector itself can change the beam forming weight vector on the time domain or the frequency domain. Furthermore, for subband space non-communication, both the LTE subband and the LTE-A subband (or other types of subbands) may be used for the noncommunication subband. If the control channel is decommissioned, a new operation for the noncommunication subband may be defined. For example, the permission information for the downlink or uplink can be transmitted through a specific subband, but the subband may be made non-communication depending on a specific environment. In this case, the control channel for permission information transmission may be moved to another subband that is not made non-communication. This can be used to manage subbands where additional control channels are spatially decommissioned (for example, decommunication on / off, weight vector change information, decommunication subband permission information, etc.) It means that it can be defined as spatial decommissioning.

6) Auxiliary channel measurement using reference signal

  Various channel measurement methods can be used for spatial non-communication according to an embodiment of the present invention. If the carrier wave received by the terminal does not include all non-communication and non-communication subbands / subframes, especially when non-communication measurement is not possible, direct channel measurement from the auxiliary carrier to which non-communication is applied It can be performed. When channel measurement is performed based on a known symbol with known information such as RS or preamble, there may be a corresponding channel including the known symbol, and the corresponding channel is defined as a plurality of small cells and macro cells. Can be shared. This known symbol is shared in advance between base stations, or the terminal receives information transmitted from an arbitrary base station in multiple ways (ie, search and receive information for multiple cells, and connection is also possible) Thus, measurement information regarding the corresponding symbol can be transmitted via the corresponding service providing cell or the terminal specific service providing cell.

  In the case of spatial non-communication according to an embodiment of the present invention, when beam forming is performed also on a reference signal (RS), a plurality of terminals located in a region where the beam forming is transmitted are transmitted to an auxiliary carrier in which path loss has occurred. Can be limited to not measure. This is because when the path loss occurs in the corresponding auxiliary carrier transmitted after beam forming, the accuracy with respect to the measured path loss is lowered depending on the beam form. Therefore, the base station according to an embodiment of the present invention informs the terminal of information on the number of antennas or the beam forming order used for transmitting the auxiliary carrier so that the measurement for the auxiliary carrier in which the path loss occurs can be accurately performed. Can do.

  Each terminal that receives this can perform measurement on a suitable auxiliary carrier. For example, if a cell common reference signal (CRS) is used for channel measurement and a CRS transmitted without beamforming from any one small cell affects other adjacent cells at a high interference level, The base station can also perform beam forming on the CRS. That is, in order to prevent interference due to the common reference signal, a base station according to an embodiment of the present invention can define beam forming for CRS.

  Here, the terminal that has received the beamforming information can perform channel measurement for each weight vector using the beamforming application weight vector, or perform channel measurement based on a unit such as a subframe or a subband. However, there may be no terminal in the subcell area where a certain beam forming is performed, and it is preferable to apply various weight vectors to the CRS depending on the subframe or frequency subband. In this case, the terminal converts the measured value of CRS into a value based on the corresponding index or band in terms of the subframe index and frequency band, and uses the same or independent subframe index or frequency band as the measured value for CRS. Can report to the station. Accordingly, the base station can determine how to apply the beamforming weight vector in order to change a cell region in which a carrier wave for providing service to a terminal is transmitted according to a predetermined rule. Similar to the designated RS, the base station can change the beamforming weight vector by subframe or frequency subband when the terminal measures the auxiliary carrier.

  If path loss occurs during auxiliary carrier transmission, the accuracy of the measured path loss may be reduced by the beam shape. However, if the beamforming order is not high enough, after the general path loss measurement error is sufficiently high by the excess beam gain, the magnitude of the beam gain itself is not important, and the path loss It can be ignored when calculating.

7) Aggregation of carriers from the viewpoint of spatial non-communication

  When the auxiliary carrier is used as an additional information carrier for one terminal, the auxiliary carrier can be represented as a terminal specific carrier for downlink reception. However, a suitable beamforming weight value for a signal transmitted directly to the terminal cannot be estimated from the auxiliary carrier wave. Therefore, the auxiliary carrier wave may be managed in a non-hearing state.

  Therefore, although the auxiliary carrier is handled as a general-purpose carrier and the base station can control the terminal operation based on carrier aggregation, it is more efficient to define another operation method based on the auxiliary carrier operation. For example, when a suitable beam weight value is already determined by channel measurement at the terminal, and the base station switches the beam weight value for adjusting the carrier transmission area, the terminal uses the auxiliary carrier wave when the terminal specific beamforming weight value is not applied. An operation may be defined in which an auxiliary carrier is received only when a specific beamforming weight value is applied without reception.

  For such an operation, the base station transmits information regarding auxiliary carrier transmission such as beamforming weight values and time / frequency subbands of beamforming weight values to system information or a terminal-specific radio resource control (RRC) signal. Must be sent to the terminal via. Such information related to auxiliary carrier transmission can be transmitted together in step S602 for transmitting beam pattern information in FIG. 6 or in step S705 for transmitting beamforming operation information in FIG. The information on the auxiliary carrier transmission includes the bandwidth for transmitting the auxiliary carrier, the beam forming pattern information such as the size and / or weight vector exchange period of each subband, weight value matrix information, antenna configuration information, and auxiliary information. One or more information of a method for measuring a received signal on a carrier wave may be included.

  Next, the base station can determine carrier aggregation based on measurement information fed back from the terminal later. When the terminal can recognize the auxiliary carrier with sufficient signal strength, the auxiliary carrier can be aggregated together with the primary carrier. Otherwise, since the terminal may not be located in the corresponding auxiliary carrier transmission area, the auxiliary carrier may not be assigned to the terminal.

8) Control through auxiliary channel and use of data channel

  The base station can adjust the control channel based on feedback information transmitted from the terminal.

  In general, since it is not guaranteed that the terminal decodes the control channel from all auxiliary carriers, a separate signal notification process for the terminal to receive the auxiliary carrier must be added.

  For this purpose, an embodiment of the present invention transmits information on a method of decoding a subband time or frequency to a terminal. A terminal that has received information on a decoding method can receive and decode a subframe that is formed by beam forming in the direction in which the terminal is located. However, since the subband time or frequency decoding setting may be defined in the higher layer signal notification via the primary carrier (or the carrier in the entire area), the decoding setting method cannot be dynamically changed.

  Accordingly, in the signal transmission method using spatial non-communication according to an embodiment of the present invention, the base station transmits information on the decoding method in order to enable a dynamic schedule on the decoding setting on an arbitrary subframe. This step can be performed after the beam pattern information transmission step in FIG. 6 or the carrier operation information transmission step in FIG. The schedule information regarding the control channel used to transmit the auxiliary carrier can be transmitted through the primary carrier. The schedule information may include instruction information that simply indicates whether to schedule the auxiliary carrier, or may include permission information regarding the auxiliary carrier.

  Here, if the schedule information includes only instruction information indicating whether to schedule the auxiliary carrier, the terminal must decode the permission information from the auxiliary carrier. Here, the decoding complexity may be reduced by instruction information including various parameters regarding the decoding position such as frequency subband, search space index, aggregation level, antenna configuration, transmission mode, and the like.

  One or more parameters included in the instruction information may be defined in advance by higher layer signal notification or L1 / L2 control signal notification. When the grant information is transmitted directly via the primary carrier, the grant information can include carrier identification information (ID) regarding the auxiliary carrier. The carrier ID can be defined based on an auxiliary carrier that can be used for each terminal or all available carriers.

  Unlike the above-described embodiment of the present invention, a method is used in which a stream is turned on / off in a spatial domain (for example, a unique beam forming region) in an uncorrelated environment, not in the same physical space as a cell region using beam forming. May be.

  Spatial de-communication according to another embodiment of the present invention uses a transmission on / off scheme in the spatial domain, and uses a scheme for turning layers on / off.

  The base station can use an on / off scheme in the spatial domain for mitigating interference between a plurality of macro cells. As an example of a method for transmitting information regarding this, information regarding whether or not to perform layer on / off may be transmitted to the terminal via RRC signal notification (for example, a bitmap). For example, when 12 physical antennas are provided in one macro cell, 3 spatial domains can be configured by 12 physical antennas. That is, it is possible to determine whether or not to transmit a signal to a specific area in the cell through a transmission on / off scheme for each of the spatial domains. At this time, each spatial domain constituting one cell can indicate whether or not to perform signal transmission on / off in each spatial domain via a 3-bit bitmap.

  As the on / off method in the spatial domain, a method of arbitrarily selecting a spatial domain for performing an on / off operation by applying a pseudo-random pattern can be used. Coin tossing can be applied to the pseudo random pattern method.

  A base station and a terminal that can implement the embodiment of the present invention will be described with reference to FIG.

  FIG. 9 is a block diagram of a base station and a terminal that can execute the embodiment of the present invention.

  The terminal can operate as a transmitting device in the uplink and operate as a receiving device in the downlink. In addition, the base station can operate as a receiving device in the uplink and operate as a transmitting device in the downlink. That is, the terminal and the base station may include a transmission device and a reception device for transmitting information or data.

  The transmitting device and the receiving device may include a processor, a module, a part, and / or a means for executing an embodiment of the present invention. In particular, the transmission device and the reception device may include a module (means) for encrypting a message, a module for analyzing the encrypted message, an antenna for transmitting and receiving the message, and the like.

  Referring to FIG. 9, the left side shows the structure of the transmitting device and represents the base station, and the right side shows the structure of the receiving device and represents the terminal that has entered the cell served by the base station. The transmission device and the reception device may include antennas 901, 902, reception modules 910, 920, processors 930, 940, transmission modules 950, 960, and memories 970, 980, respectively.

  The antennas 901 and 902 include a reception antenna that performs a function of receiving a radio signal from the outside and distributing it to the reception modules 910 and 920, and a transmission antenna that transmits the signals generated by the transmission modules 950 and 960 to the outside. . The antennas 901 and 902 may include two or more when providing a multiple antenna (MIMO) function.

  The receiving modules 910 and 920 can decode and demodulate a radio signal received from the outside via an antenna to restore it to the form of original data, and distribute it to the processors 930 and 940. The reception module and the antenna may be a reception unit for receiving a radio signal without being separated as shown in FIG.

  The processors 930 and 940 generally control the overall operation of the transmitter or receiver. In particular, the controller function for carrying out the embodiment of the present invention described above bears a medium connection control (MAC) layer frame variable control function, a handover function, an authentication and encryption function, etc. according to service characteristics, wireless environment, etc. be able to.

  The transmission modules 950 and 960 can deliver the data to the antenna after performing predetermined encoding and modulation on the data scheduled and transmitted to the outside by the processors 930 and 940. The transmission module and the antenna may be a transmission unit for transmitting a radio signal without being separated as shown in FIG.

  The memories 970 and 980 may store programs for processing and control in the processors 930 and 940, or may temporarily store input / output data. In the case of a mobile terminal, the temporarily stored input / output data may include uplink permission allocated from the base station, system information, a base station identifier (STID), a flow identifier (FID), an operation time, and the like.

  The memories 970 and 980 are flash memory type, hard disk type, multimedia card micro type, card type memory (for example, SD or XD memory), RAM, SRAM, ROM, EEPROM, PROM, magnetic memory, magnetic disk. , Including at least one type of storage medium of optical disks.

  The processor 930 of the transmitting apparatus performs a general control operation on the base station, and, according to the embodiment of the present invention described above with reference to FIG. 5, generates an auxiliary carrier wave using spatial non-communication in the macro cell area where the base station provides services. Can be sent. For example, a method of changing the beam direction or exchanging the position according to a predetermined rule while performing beam forming on the auxiliary carrier wave as in the above-described embodiment can be used.

  For this purpose, when information on a set of weight vectors that can be used by the transmission apparatus is transmitted to the reception apparatus via the transmission module 950, the processor 940 of the reception apparatus transmits a channel measurement result for each weight vector to the transmission apparatus in a feedback manner. Can do. That is, the processor 930 of the transmission apparatus can perform beam forming by determining a weight vector used when transmitting a carrier wave to the reception apparatus based on the received feedback information.

  In this process, the processor 930 of the transmission apparatus can perform the processes 1) to 8) in addition to the embodiment described above with reference to FIG.

  The processor 940 of the receiving apparatus performs the overall control operation of the terminal. In addition, according to the above-described embodiment of the present invention, the carrier operation information (information regarding the beam forming application method) transmitted from the transmission apparatus as information regarding the non-communication of space is received via the reception module 920 and used for the carrier reception. be able to.

  The processors 930 and 940 can be configured to transmit the respective control information described in the embodiments of the present invention via separate signal notification instead of the DM-RS. On the other hand, the base station performs a controller function, an orthogonal frequency division multiple access packet schedule, a time division duplex communication packet schedule and a channel multiplexing function, a service characteristic, and a MAC according to the wireless environment for implementing the embodiment of the present invention described above. Among the above-mentioned modules, the frame variable control function, high-speed traffic real-time control function, handover function, authentication and encryption function, packet modulation / demodulation function for data transmission, high-speed packet channel coding function and real-time modem control function, etc. It may be executed by at least one, and may further include a separate means, module, or part for performing such a function.

  The detailed description of the preferred embodiments of the present invention disclosed above is provided to enable any person skilled in the art to implement and practice the present invention. Although the present invention has been described with reference to the preferred embodiments of the present invention, it will be understood by those skilled in the art that various modifications and changes can be made to the present invention without departing from the scope of the present invention. Can understand. For example, those skilled in the art can use the configurations described in the above embodiments in a combination manner.

  Accordingly, the present invention is not limited to the embodiments disclosed herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

  The embodiments of the present invention can be applied to various wireless connection systems. Examples of various wireless connection systems include 3GPP, 3GPP2 and / or IEEE802. xx system.

  The embodiment of the present invention can be applied to any technical field to which these various wireless connection systems are applied in addition to the above various wireless connection systems.

Claims (15)

A method in which a base station transmits a signal in a heterogeneous network,
Transmitting to a plurality of terminals information related to a set of weight vectors including one or more weight vectors applicable to a reference signal carried by an auxiliary carrier via a downlink control signal carried by a primary carrier;
Transmitting the reference signal to which each weight vector included in the weight vector set is applied to the plurality of terminals;
Receiving feedback information related to a result of channel measurement of the reference signal from the plurality of terminals;
Determining weight vector information for forming a beam pattern to be applied to the auxiliary carrier based on the feedback information, the weight vector information being applied to a downlink signal carried by the auxiliary carrier; Specific to each of the plurality of terminals, steps ,
And transmitting the carrier operational information including information related to the determined weighting vector information, to the plurality of terminals via the primary carrier,
Transmitting the auxiliary carrier carrying the downlink signal using the determined weight vector information to each of the plurality of terminals ;
Having a method.   The method according to claim 1, wherein the auxiliary carrier and the primary carrier are carriers transmitted via separate frequency partitions among a plurality of frequency partitions constituting an available system band. Determining a pre Kikasane viewed vector, a carrier macrocells said base station provides uses, and small cell contained within the macrocell and the carrier is a case selectively performed overlapping used, to claim 1 The method described. Receiving feedback information including interference information relating to interference between a plurality of cells related to the channel measurement from the plurality of terminals,
Adjusting a region in which the auxiliary carrier is transmitted after beam formation in a macro cell served by the base station based on the interference information;
The method of claim 1, further comprising: Determining a weight vector for forming a beamforming to be applied to the reference signal;
Transmitting reference signal operation information including at least one of information related to the order of beam forming applied to the reference signal and information related to the number of antennas;
Transmitting the beamformed reference signal;
The method of claim 1, further comprising: The step of determining a weight vector for forming a beam forming to be applied to the reference signal applies a separate weight vector to the cell common reference signal according to each of a plurality of frequency partitions constituting an available system band. 6. The method of claim 5 , comprising determining the weight vector . Transmitting information on auxiliary carrier transmission to the terminal, including information related to time / frequency resources to which a beam forming weight value and beam forming weight value to be applied to the auxiliary carrier are applied;
Receiving feedback information including a result of channel measurement using the auxiliary carrier from the terminal;
Performing carrier aggregation on the auxiliary carrier using the feedback information;
The method of claim 1, further comprising: A method in which a terminal receives a signal in a heterogeneous network,
Receiving from the base station information related to a set of weight vectors including one or more weight vectors applicable to a reference signal carried by the auxiliary carrier via a downlink control signal carried by the primary carrier;
Receiving the reference signal to which each weight vector included in the weight vector set is applied from the base station;
Sending feedback information related to the result of channel measurement of the reference signal to the base station;
And receiving a carrier operational information that includes information relating to the weight vector information determined for the formation of the beam pattern to be applied to the auxiliary carrier from the base station, the weight vector information based on said feedback information Applied to the downlink signal carried by said auxiliary carrier, and
Receiving the auxiliary carrier waves transporting the downlink signal according to the pre Kiomomi vector information from the base station,
Having a method. Performing channel measurements using downlink signals received from the base station;
Transmitting feedback information including interference information related to interference between a plurality of cells related to the channel measurement to the base station;
The method of claim 8 , further comprising: The method according to claim 8 , wherein the auxiliary carrier and the primary carrier are carriers transmitted through separate frequency partitions among a plurality of frequency partitions constituting an available system band. A base station in a heterogeneous network,
A transmission module for transmitting radio signals;
A receiving module for receiving radio signals;
A processor for determining weight vector information for forming a beam pattern to be applied to an auxiliary carrier transmitted through the transmission module,
The processor is
Transmitting to a plurality of terminals information related to a set of weight vectors including one or more weight vectors applicable to a reference signal carried by an auxiliary carrier via a downlink control signal carried by a primary carrier;
Transmitting the reference signal to which each weight vector included in the weight vector set is applied to the plurality of terminals;
Receiving feedback information related to the result of channel measurement of the reference signal from the plurality of terminals;
The weight vector information is applied to a downlink signal carried by the auxiliary carrier based on the feedback information, and is specific to each of the plurality of terminals;
Transmitting carrier operation information including information related to the determined weight vector information to the plurality of terminals using a primary carrier;
Using front weight vector information determined reporting, the auxiliary carrier waves transporting the downlink signal configured to send to each of the plurality of terminals, a base station. A terminal in a heterogeneous network,
A receiving module for receiving radio signals;
A transmission module for transmitting radio signals;
A processor for measuring a channel based on a downlink signal received via the receiving module,
Receiving from the base station information related to a set of weight vectors including one or more weight vectors applicable to a reference signal carried by the auxiliary carrier via a downlink control signal carried by the primary carrier;
Receiving, from the base station, the reference signal to which each weight vector included in the weight vector set is applied;
Sending feedback information related to the result of channel measurement of the reference signal to the base station;
The carrier operational information that includes information relating to the weight vector information determined for the formation of the beam pattern to be applied to the auxiliary carrier wave received from the base station,
The weight vector information is determined based on the feedback information and applied to a downlink signal carried by the auxiliary carrier;
A terminal configured to receive, from the base station, the auxiliary carrier that carries the downlink signal to which the weight vector information is applied. The terminal receives, using the primary carrier, information related to a weight vector set including one or more weight vectors applicable to the auxiliary carrier from the base station via the reception module, and the weight vector when the respective weight vectors in the set receives the applied downlink signal, wherein the processor performs the channel measurement of the downlink signal each weight vectors included in the weight vector set is applied generates feedback information related to the result of the channel measurement, that sends to the base station through the transmission module, the terminal according to claim 12. The terminal according to claim 12 , wherein the feedback information includes interference information related to interference between a plurality of cells related to the channel measurement. The terminal includes, via the receiving module, a weight vector for forming beamforming applied to the auxiliary carrier from the base station and information related to time / frequency resources to which beamforming weight values are applied. upon receiving information about the carrier transmitter, wherein the processor generates the feedback information including the results of the auxiliary carrier channel measurement using, that sends the feedback information to the base station through the transmission module, The terminal according to claim 12 .

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